Even though the TFT-LCD industry gained enough momentum that has been built up in past 10 years, the industry faces new challenges in order to maintain the 'true mainstream display' position in near future. The technical challenges can be summarized in two fold; one is image quality upgrade for different application area. Cost competitiveness is the other big issue in LCD for the continued leadership position in display industry. In this paper, we describe the technology advancement and the technical challenges in LCD to achieve these goals..

Si TFTs are applied not only to stacked SRAM but also to FPD. Improvement of device characteristic such as an enhancement of carrier mobility or a reduction of leakage current is studied intensively. The TFT technology is developing based on conventional Si LSI technology. By establishing a stable fabrication process on flexible substrate and high performance characteristic uniformly and reliably, TFT technology has a possibility to develop to SOP or other highly functional applications similar to or beyond the conventional Si LSI in the era of information and telecommunication.

Freestanding azobenzene-containing liquidcrystalline network (LCN) films. with macroscopic uniaxial molecular alignment were prepared by insitu photopolymerization. By polarizing microscopy, fiber-like structures aligned in one direction were observed. Furthermore, with a confocal laser scanning microscope (CLSM), it was confirmed that the fiber-like structures were formed even in the bulk of the LCNs. Upon UV light irradiation to cause trans-cis photoisomerization of the azobenzene molecules, the LCNfilms underwent a significant and anisotropic bending toward the irradiation direction of UV light. When the bent LCNfilms were exposed to Vis light, unbending of the LCN films immediately took place and the initial flat LCN films were restored. This bending and unbending behavior of the LCN films could be repeated just by changing the wavelength of the irradiation light. It was suggested that the bending was induced by an absorption gradient which produced a volume difference between the front surface area and the bulk of the network films.

Small sized LTPS TFT-LCDs are developed and evaluated. Sine the fabrication process is optimized for the productivity of huge glass substrate, the pattern size is above 5${\mu}m$. The panels with integrated digital data drivers are not satisfactory to compete with a-Si technology. Therefore, LTPS panels are implemented by PMOS technology and it is proved that they can be competitive with a-Si TFT-LCDs in terms of performance and cost.

Recent trends of low-temperature polycrystalline Si (LTPS) TFT technologies are presented. Characteristics of LTPS TFT processes are compared with those of a-Si TFT's. In order to compete with well-established a-Si TFT-LCD technology, LTPS process has to be as simple as possible. One of the most critical processes, recrystallization of a-Si thin films, could be the process for the differentiation of LTPS technology. Along with these technical reviews, a recent development of the 5.0-inch LTPS TFT-LCD is presented. In order to achieve high-performance display characteristics and save the power consumption, the transflective mode is adopted. The 5.0-inch display with 186 pixel-per-inch, high-resolution LCD was measured to be 10% for the reflectance and 70:1 for the contrast ratio. This display is designed for a high information content hand-held PC (HHPC) application.

Samsung's newly developed high luminance efficiency 42" VGA plasma display panel is introduced. A new discharge cell structure, SDR (Segmented electrode in Delta color arrayed Rectangular subpixel) has been applied to a full size panel for the first time. In this paper, we describe how this new discharge cell structure for high efficiency is integrated to an energy saving plasma display with better picture quality.

This paper deals with the effect of ramp-type erase pulse waveform on the high temperature driving characteristics of ac PDP driven by ramp up-down reset waveform. The experimental results show that the discharge characteristics in the reset period are significantly affected by the erase pulse waveform and ambient temperature. The firing voltage is increased with ambient temperature. This can cause misfirings during the sustain period and should be avoided. As one of possible solutions, we propose the optimization of erasing pulse shape.

The discharge characteristics of AC plasma display were investigated as a function of the voltage and the frequency of the pulses applied to the address electrode during sustain period. The maximum sustain voltage of display cell decreased with increasing the frequency of the pulses applied to the address electrode during sustain period. Applying the pulses to the address electrode resulted in improvement of luminance and luminous efficiency at the same time.

A new driving scheme is proposed to improve the color purity by reducing the neon (Ne) emission of 585 nm in an ac PDP. Applying the new driving scheme to the address electrodes during a sustain-period induces a new discharge mode that can reduce the Ne emission remarkably. For this new discharge mode, the change in the Ne emission intensity including the discharge characteristics is measured and the corresponding mechanism is also analyzed. As a result, it is found that a color gamut area is expanded by approximately 9.2 % in comparison with a conventional case.

It is necessary to increase VUV radiation for improve luminous efficiency of PDP . It is important to know wave-forms of VUV radiation and density of exited Xe atoms or 1S4 and 1S5 of the cells. We survey on their measurement methods.

Difference in the structure of AC PDP cells makes the cells have various discharge characteristics. Therefore, a ramp-reset must be adjusted for the stable driving of AC PDP. If any ramp-reset can reduce the difference in discharge characteristics between cells, the conditions of the address discharge could become almost the same. It is very important to understand these to design a good driving waveform. In this paper, we proved the mentioned facts with the change of barrier rib heights.

In this paper, we investigate the characteristics of luminous efficacy as a function of Xe partial pressure in AC PDP. SDR structure has shown much larger increment of luminous efficacy compared with the conventional one especially below 10% Xe contents. The luminous efficacy around 4.0 lm/W is achieved with Ne-Xe10%, 400Torr in Monochrome green phosphor test panel under 10kHz continuous sustaining frequency.

This paper presents a new self-erasing discharge mode for the improvement of luminous efficiency and color purity of an AC plasma display panel (AC PDP). A new self-erasing discharge mode is produced between successive sustain pulses. by simultaneously applying the auxiliary short pulses at the falling edge of the sustain pulses without cross-talk during a sustain period. As a result. the luminous efficiency and color gamut are improved by 16% and 5%, respectively.

We present both a theoretical analysis and experimental data to show that electrophosphorescent top-emitting organic light emitting-devices (TOLEDs) with a reflective anode and a transparent cathode can be more efficient than the equivalent state-of-the-art bottom-emitting electrophosphorescent OLEDs (PHOLEDs$^{TM}$). The lifetime of devices with transparent cathodes are shown to approach that of the corresponding bottom-emitting devices.

We report highly efficient phosphorescent-dye-doped polymeric light-emitting devices. The devices consist of a polymeric light-emitting layer comprising the phosphorescent dye, host, and matrix polymers. We patterned the phosphorescent-dye-doped polymeric layer with the LITI technique. The devices showed high efficiencies and good pattern quality to adapt to the development of full-color electroluminescent (EL) devices.

The effect of morphology on energy transfer and device performance in phosphorescent dye doped polymer light emitting diodes is reported. We selected two host polymers (PVK and PFHP) which have nearly the same potential for the energy transfer to Ir(ppy)$_3$. The PFHP:Ir(ppy)$_3$ film showed b-micron size aggregation, whereas the PVK:Ir(ppy)$_3$ film showed homogeneous and smooth images. As a result, energy transfer is efficient with high emission efficiency in PVK:Ir(ppy)$_3$ whereas little energy transfer and low quantum efficiency are obtained in PFHP:Ir(ppy)$_3$.

The device characteristics and the interface electronic structures of organic light-emitting devices based on tris-(8-hydroxyquinoline)aluminum were investigated with $Al/CaF_2$, Al/LiF, and Al-only cathodes. Similar to the Al/LiF cathode, the $Al/CaF_2$ cathode greatly improved the performance of the device over Al-only cathode. However, a photoelectron spectroscopy study revealed that despite the performance improvement, the evolution of the new peaks during $Al/CaF_2$ cathode formation closely resembled those of the Al-only cathode rather than the Al/LiF cathode.

A new pixel driving method for organic light-emitting diode (OLED) flat-panel display (FPD) is proposed. The new charge-pump passive-matrix pixel driver consists only of a storage capacitance and a rectifying diode, and no thin-film transistor (TFT) is needed. The new driver not only supplies a constant current to the OLED throughout the whole period of panel scanning like an active-matrix driver, but also provides a highly linear gray-scale control through a pure digital manner.

In order to realize a stable rubbing process for the liquid crystal panel, the authors investigated the quantitative evaluation method of rubbing process uniformity. The proposed method focuses on the relationship between the image quality of the LCD panel for gray scale images and the rubbing uniformity. The proposed method indicates rubbing uniformity using quantitative parameters of spots and hairlines on the LCD panel.

In this study, we describe the development of viscous inspection equipment for flatron panel glass by Moire phenomenon and propose a new idea to develop an automatic inspection system for viscous or cord defects. It is possible to detect string viscous more easily and the equipment is practically being applied in production line. After using this equipment, the ratio of defective from customer is dropped significantly.

Measuring color precisely requires the use of a colorimeter whose spectral response is as close as possible to the CIE response. Some techniques such as the NIST 4-color method can improve the precision. but under given conditions, the results can be worse.

It is very important to get a stable and large-capacity organic effusion source for achievement of OLED mass-production equipment. We present an organic effusion source with film uniformity less than ${\pm}$ 5%, the material charge volume, 300cc for $400{\times}400\;mm^2$ substrate. The fine metal shadow mask alignment technology, one of the color forming technique, also have to support more accurate and fast operating in mass-production. In this paper, we will describe the OLED mass-production equipment with the large volume effusion source and the precision shadow mask alignment technique.

The frequency response analysis of complex impedance spectra using small perturbation ac impedance spectroscopy is an informative method of OLED performance characterization and lifetime analysis. Using simple RC equivalent circuit mode,l macroscopic nonliniear transport properties of semiconductive emission/transport layers can be analyzed and parameterized. We present the bias voltage dependence and aging effect in impedance spectra measured from an ITO/CuPC/TPD/$Alq_3$/LiF/Al OLED device, and discuss possible failure mechanism based on impedance model parameters.

Litrex Ink Jet equipment offers prospect for reliable and low cost manufacturing process for PLED technology. The design concept of 140P system that we are developing meets requirement of process/equipment for PLED manufacturing line in terms of higher mechanical accuracy, in-line monitoring system of print head, high precision of process capability, reasonable through-put, high reliability/easier maintenance and no particle generation.

A new theory of thin film growth was suggested, where charged clusters of nanometer size are generated in the gas phase and are a major flux for thin films. The existence of these hypothetical clusters was experimentally confirmed in the diamond and silicon CVD processes as well as in metal evaporation. These results imply new insights as to the microstructure control of thin films. Based on this new understanding, the low temperature deposition of crystalline and amorphous silicon can be approached systematically.

We have developed a pixel structure for reflective color TFT-LCD which can display 27-color in still-image. The proposed pixel can display 3 gray scale in still image; white, black and median gray. This paper shows the concept and the driving method of the proposed pixel. Finally this paper compares power consumption and area with the Toshiba's DMOG technology.

This paper reviews an advanced excimer-laser crystallization technique enabling precise location-control of the individual grains. With the developed ${\mu}$-Czochralski (grain-filter) process, the large grains having a diameter of 6 ${\mu}m$ can be set precisely at predetermined positions. We will also discuss the performance of the single-crystalline Si TFTs that are formed within the location-controlled Si grains. The field-effect mobility for electrons is 430 $cm^2/Vs$ on average, which is well comparable to that of TFTs made with silicon-on-insulator wafers.

We studied the growth of large-grain pentacene film by organic vapour phase deposition. The optimizations of the growth of pentacene are carried out by varying the gas pressure in the reactor and substrate temperature. We found that the grain size depends strongly on the gas pressure in the reactor. The grain size of $20{\mu}m$ has been obtained at the gas pressure of 200 Torr. The film was found to be strongly (001) oriented and its grain size decreases with decreasing the gas pressure.

We have proposed new pixel structures for Active Matrix OELD (AMOELD) to improve the uniformity of luminance and manufactured a full-color 3.6-inch QVGA AMOELD. The proposed pixel structures, composed of four TFTs and one capacitor, can display 64 gray scales by compensating threshold voltage (Vth) variation of driving TFTs. Nonuniformity and peak intensity of measured luminance are under 14% and over $200cd/m^2$, respectively.

When boron ions are doped into the poly-Si films, the hydrogen ions doped with boron ions compensate the defect sites and suppress to produce damage density. These samples can be easily activated by hydrogen doping at high acceleration voltage($V_{acc}$).

Microwave has been utilized for low-temperature crystallization of amorphous Si films. Microwave annealing lowered the crystallization temperature and shortened the annealing time. The combination of Ni and microwave applications on a-Si films further enhanced the crystallization. The enhancement was due to both reduced nucleation activation energy and growth activation energy.

A new 10.4" transflective TFT-LCD has been developed using newly designed color filter for sunlight readable application. High transmittance and color gamut are realized by the dual color filter and dual cell gap structure in the ECB mode. The color gamut of new device provides 17% in transmissive and 18% in reflective mode. This new device provides the $125cd/m^2$ of luminance, 240:1 and 27:1 of contrast ratio in the transmissive and reflective mode, respectively.

In this work, the electrical characteristics of organic thin film transistors with the stacked organic gate insulators have been studied. PVP(Polyvinylphenol) and polystyrene were used as gate insulating materials. Both the high dielectric constant of PVP and better insulating capability of polystyrene were compensatorily adopted in two different stacking orders of PVP-polystyrene and polystyrene-PVP. The output characteristics of the device with the stacked gate insulator showed substantial improvement compared with those of the devices with either PVP or polystyrene gate insulator: Furthermore, these stacked organic gate insulators can differently affect the TFT characteristics with the stacking orders. The electrical properties of TFTs with organic gate insulators stacked in different orders are discussed.

We reported pushing of colloidal particles by a moving isotropic-nematic phase boundary. Here, we report tailoring the structure of 3-dimensional networks formed by these particles by adjusting the rate of phase transition and by application of an electric field. The resulting networks affect the electro-optic performance of liquid crystal devices.

We report a fast-switching polymer-stabilized bend nematic (PSBN) device. The morphology study reveal a templated polymer networks captures the orientation of the field deformed nematic host.

In general, the background light produced during the reset period deteriorates the dark room contrast ratio in AC PDP. In this paper, we propose a modified ramp reset pulse that can reduce the background light to imperceptible level. In the new reset waveform, the discharges between the scan and sustain electrodes are minimized by applying a positive bias voltage to the sustain electrode and only the weak discharges between the scan and address electrodes occur during the reset period. We adopted a MgO coated phosphor layer to get the same level of voltage margin in the new reset pulse scheme compared to that of the conventional ramp reset pulse one. As a result, the voltage margin is maintained at the same level and the dark room contrast ratio is improved dramatically.

In this study, a new driving method is suggested to improve the dark room contrast ratio. The principles of the method are that the reset facing discharges occur between scan and address electrodes instead of surface discharge and that the discharge occurs only for the cells that experienced sustain discharge in preceding sub-field after the first sub-field. The dark room contrast ratio is improved more than 7 times compared with the conventional method.

This paper presents a new driving method that can drive AC PDPs with low voltage and controlled-current for the sustaining period. The discharge current flowing into the AC PDP is limited in this method. Thus, the power consumption for the discharge is reduced and the discharge input power to output luminance efficiency is improved. Experimental results using this driving method showed that we could drive an AC PDP with a voltage source as low as 146 V and that luminous efficiency of 1.33 lm/W can be achieved.

We present gray scale implementation method based on QMA driving technique. We clarified the mechanism of wall charge quantization through discharge current measurement. We used three wall charge states to implement gray scale. The cells would be one of fully-ON, half-On, and OFF states. We built a five sub-fields 243 level gray scale with sustain pulse count of 2, 6, 18, 54, and 162.

In this paper, an accelerated lifetime test method of MgO thin film is suggested. The most important test factors are surface temperature of the PDP, gas pressure, the applied voltage and frequency. The standard test conditions are $50^{\circ}C$, 400Torr, 20% over voltage and 300kHz ,respectively. The accelerated lifetime of MgO is significantly varied with the MgO preparing conditions.

We have measured the secondary electron emission yield ${\gamma}_i$ from MgO films deposited on $SiO_2/Si$ for low energy noble ions. A pulsed ion beam technique was employed in order to suppress the surface charging effect during the measurement. From the measurement of the ion - induced secondary electron emission coefficients ${\gamma}_i$ for 5 noble ions with energies ranging from 50 eV to 225 eV, it was shown that, with increasing the kinetic energies of the incident ions, the ${\gamma}_i$ increased

The relationship between the discharge aging time and the superficial layer thickness of MgO thin film was investigated in an AC PDP. The discharge characteristics of an AC PDP with the various aging time were evaluated by discharge aging experiments. We find the presence of a superficial lay which is related to the discharge characteristics during aging process. The superficial layer of MgO thin film was observed by Transmission Electron Microscope (TEM). It was found that the superficial layer thickness of MgO was dependent on discharge aging time.

We report the effect of density of thin films on moisture adsorption and hydration of MgO thin film, usually used as a protective layer in AC-PDP After hydration, lots of hemispherical shaped clusters, $Mg(OH)_2$, formed on the surface of MgO thin films. However clusters formed on low-density thin films were bigger than those on high-density films. From ERD spectra, it seemed that the concentration of hydrogen was very high in the region 20 nm from the surface of MgO thin film. The low-density thin film had more hydrogen than high-density thin film. From simulation results of ERD and RBS it was found that hydration reaction also occurred in the inner part of the film. So diffusion of Mg atoms from the inner part of the film to the surface and $H_2O$ molecules from the surface to the inner part of the film is important. And because low density thin film has many short paths for diffusion of Mg atoms and $H_2O$ molecules, low-density thin film is more hydrated. So to suppress hydration of MgO thin films, high-density thin film is needed.

An alternate application of MgO film for the improvement of discharge characteristics and life time in an ac plasma display panel (PDP) is suggested. In this research, we deposited MgO on the phosphor to get the same address characteristics irrespective of each phosphor. To avoid the luminance and efficiency degradation by MgO deposition on the phosphor, we optimized the MgO thickness through experiments. The results showed that PDP with MgO coated phosphor has a uniform formative delay in address discharge and improved degradation characteristics.

Luminescence efficiency of phosphors, $SrTiO_3;Pr^{3+}$ and $SrIn_2O_4:Pr^{3+}$, is increased remarkably by III-group impurities. This effect is explained by a picture that carriers thermally released from impurity-induced traps supply energy to $Pr^{3+}$ ions. The impurities also improve carrier transport efficiency by reducing lattice defects. This picture indicates a possibility to develop new ternary oxide phosphors.

We propose a new concept: that of photonic crystal phosphors (PCPs) for display and phosphor related applications. It is well known that microcavities with dimensions comparable to the emitting wavelength strongly enhance light-matter interactions, resulting in a significant increase in spontaneous emission rate, which can be directly translated into enhancement in phosphor efficiency. In recent simulations we have demonstrated that when a microcavity is formed in a nano-phosphor structure, the luminescence band is modified, and can be made spectrally sharp and tunable by engineering the geometry/material properties of the cavity and the surrounding photonic crystal lattice. New phosphor material structures based on photonic crystals are proposed. Applications to thin film EL phosphors and particle phosphors are discussed. Additionally, economic methods of synthesizing and incorporating PCPs into current display applications are proposed.

$Gd_2O_3$:Eu phosphor particles were prepared by largescale ultrasonic spray pyrolysis process. The morphological control of $Gd_2O_3$:Eu particles in spray pyrolysis was performed by adding polymeric precursors into spray solution containing nitrate salts. The effect of composition and amount of polymeric precursors on the morphology, crystallinity, and photoluminescence characteristics of $Gd_2O_3$:Eu particles was investigated. The influence of chain length of PEG on the morphology and photoluminescence intensity was investigated. $Gd_2O_3$:Eu particles prepared from aqueous solution containing no polymeric precursors had a hollow structure and rough surfaces after annealing process. The phosphor particles prepared from solution containing 0.1M CA and 0.lM PEG with high molecular weight as 1,500 had a spherical and filled morphology and the highest photoluminescence intensity, which was 48% higher than that of the $Y_2O_3$:Eu commercial product.

As a new host material for a red phosphor for PDP applications, has studied (Y,Gd)$Al_3(BO_3)_4$ which gives non-centrosymmetric sites for $Eu^{3+}$ activators. Vacuum ultraviolet (VUV) excitation spectrum of new red phosphor (Y,Gd)$Al_3(BO_3)_4$:$Eu^{3+}$ has two broad bands. One band with the absorption edge at ca. 168 nm is the band-gap absorption of aluminoborate and the other broad band centered 240 nm is the charge transfer transition between $Eu^{3+}$ and the neighboring oxygen anions. The PL spectrum shows the strongest emission at 617 nm due to the electric dipole $^5D_0{\rightarrow}^7F_2$ transition of $Eu^{3+}$, whose luminescent chromaticity is (0.67, 0.33).

We are standing at the beginning of the industrialization of flexible thin-film transistor backplanes. An important group of candidates is based on silicon thin films made on metal or plastic foils. The main features of amorphous, nanocrystalline and microcrystalline silicon films for TFTs are summarized, and their compatibility with foil substrate materials is discussed.

Phtalocyanine derivative thin films were accumlated on ITO glasses by a Langmuir-Blodgett method. The layered structure and chromogenic properties of the films were investigated. We observed color changes which took place probably according to modulations of electronic distributions in the molecule. The novel chromogenic mechanism which can be applied to future FPD's was proposed.

We have developed a new COG technique using flip chip solder joining technology for excellent resolution and high quality LCD panels. Using the eutectic Bi-Sn and the eutectic In-Ag solder bumps of 50-80 ${\mu}m$ pitch sizes, a ultrafine interconnection between IC and glass substrate was successfully made at or below $160^{\circ}C$. The contact resistance and reliability of Bi-Sn solder joint showed the superiority over the conventional ACF bonding.

Conductive adhesives are commonly used for the interconnections of fine pitch, small packages like mobile applications. Since conductive particles connect mechanically with contact pads to give somewhat higher contact resistance, a metallurgical interconnection, which provides both fine pitch and low resistance, was studied using silver ball and indium which can be made at low temperatures. The connection resistance of the In-Ag metallurgical interconnection was lower than that of the Ni/Au-Ag mechanical interconnection and the former showed little dependency on the bonding load in contrast to the latter.

We first review a real-time holographic recording technique called optical scanning holography (OSH) and discuss holographic reconstruction using spatial light modulators (SLMs). We then present how the overall system can be used for three-dimensional (3-D) holographic television (TV) system and address some of the issues encountered. Finally, we suggest some techniques to alleviate the issues encountered in such a 3-D holographic TV.

We propose the use of synchronously moving micro-optics (lenslet arrays) for image pickup and display in three-dimensional integral imaging to overcome the upper resolution limit imposed by the Nyquist sampling theorem. With the proposed technique, we present an all-optical three-dimensional integral imaging projector. An optically addressed spatial light modulator is used, which potentially provides better image resolution than the conventional CCD and liquid crystal display pair. We present experimental results using a liquid crystal light valve.

A new technique to construct an auto-stereoscopic display that offers massive horizontal parallax images is proposed Multiple telecetnric imaging systems are arranged in a modified 2D array. The horizontal parallax images displayed by LCD panels are imaged to be superimposed on a 3D screen. All parallax images are displayed in the different horizontal directions because all imaging systems have different horizontal positions. The difference of the vertical display directions due to the imaging system's vertical positions is canceled by a vertical diffuser placed at the 3D screen. Observers can percept 3D images with the binocular disparity, the vergence, and the smooth motion parallax. In addition, the accommodation function may also work because a number of parallax images are displayed with a very small angle interval in the horizontal direction. A prototype 3D display including 64 color LCD panels was constructed.

Surface relief holograms are fabricated by means of irradiation of laser interference patterns. The diffraction efficiency and the surface relief depth depend on the writing energy and the polarization of the writing laser beam. This structure is very stable at temperatures under glass transition temperature $T_g$ and can be erased by heating above $T_g$. We proposed a new technique to control the surface relief structure. The electric charge was deposited on the surface relief grating in a corona-depositing poling setup in an oven. The first-order diffraction efficiency measured before and after corona discharge increased from about 0.24 % to about 28 %. This diffraction efficiency increase is mainly caused by the increase of the relief depth caused by the electric charge. The relief depth is increased from 20 nm to 350 nm by corona charging. .

Vacuum microelectronics has been expected to provide a number of advanced devices such as flat panel displays, high-frequency devices etc., and rapidly showing tremendous and attractive aspects toward nanotechnology. Nowadays, nanomachining and nanomaterials are coming to new targets in the development for new generation devices. Transfer Mold technique has been developed for the vacuum nanotechnology. Carbon nanotubes (CNTs) are emerging as nanomaterials and expecting the new electron sources for FED. Recent progress of vacuum microelectronics toward vacuum nanotechnology in Japan are described.

32"-diagonal gated carbon nanotube(CNT) cathodes named under-gate cathodes for large-size display applications have been fabricated and characterized. The emission uniformity looks fine, even without the resistive layer. The emission performance has been improved by scaling down the cathode electrode dimension.

Field emission from single-walled carbon nanotubes (SWNTs) aligned on a patterned gold surface is reported. The SWNTs emitters were prepared at room temperature by a self-assembly monolayer technique. SWNTs were cut into sub-micron length by sonication in an acidic solution. Cut SWNTs were attached on the gold surface by the reaction between the thiol groups and the gold surface. The field emission measurement showed that the turn-on field was 4.8 $V/{\mu}m$ at the emission current density of 10 ${\mu}A/cm^2$. The current density was 0.5 $mA/cm^2$ at 6.6 $V/{\mu}m$. This approach provides a novel route for fabricating CNT-based field emission displays.

Triode field emitters with planar-carbon-nanopaticle (CNP) cathodes were successfully fabricated using the conventional photolithography and the hotfilament chemical vapor deposition. Electron emission from a CNP triode emitter with a 12-${\mu}m$-diameter gate hole started at the gate voltage of 45 V, and the anode current reached the level of ${\sim}120$ nA at the gate voltage of 60 V, respectively. For the quantitative analysis of the Fowler-Nordheim (F-N) type emission from a CNP triode emitter, we carried out 2dimensional numerical calculation of electrostatic potential using the finite element method. As it turned out, a radial variation of electric field was very important to account for the emission from a planar emitting layer. By assuming the graphitic work function of 5 eV for CNPs, we were able to extract a consistent set of F-N parameters, together with the radial position of emitting sites.

Light emitting thin film structures based on organic luminophors embedded in porous alumina matrixes are discussing. The optical properties of the luminophors in a matrix differ greatly from their properties in usual crystalline state or in a solution and they depend on the concentration of luminophors molecules of up to 10-2 mol/l. Successful experiments on filling of pores with organic luminophors and the investigation of their luminescent and optical properties were carried out.

We will report the latest developments in light emitting polymer (LEP) systems developed at CDT. Device performance for spin coated and ink jet printed systems will be described which are state-of-the-art. We will also report on novel driving schemes for both active and passive addressed LEP displays. These drive schemes extend system lifetime as well as lowering power consumption.

We developed a high performance 2.2" active matrix OLED display for IMT-2000 mobile phone. Scan and Data driver circuits were integrated on the glass substrate, using low temperature poly-Si(LTPS) TFT CMOS technology. High efficiency EL materials were employed to the panel for low power consumption. Peak luminescence of the panel was higher than 250cd/$m^2$ with power consumption of 200mW.

Excellent organic electroluminescent materials are needed to realize color EL devices with high performance. We have succeeded in realizing bright and efficient devices with long lifetime in red and white color regions, based on a new fused aromatic ring derivative.

Fluorenevinylene-based EL polymers, poly(9,9-dioctylfluorene-2,7-vinylene) (PFV) and poly[(9,9-dioctylfluorene-2,7-vinylene)-co-{2-methoxy-5-(2 ethylhexyloxy)-1,4-phenylenevinylene}] (PFV-co-MEH-PPV), have been synthesized by Gilch polymerization method. The resulting polymers were soluble in common organic solvents and easily spin cast onto the indium-tin oxide (ITO) substrate. The weight average molecular weight and polydispersity of PFV and PFV-co-MEH-PPV were in the range of 22.2 - 43.2 x $10^4$ and 1.9 - 3.0, respectively. Double-layer light-emitting diodes with ITO/PEDOT/Polymer/Al configuration were fabricated. PFV-co-MEH-PPV showed better EL properties than those of PFV and MEH-PPV The turn-on voltage of poly(9,9dialkylfluorene) derivatives were dramatically decreased to the 2.5 V compared to fluorene-based EL polymers. The maximum brightness and luminescence efficiency were up 7 to 1350 cd/$m^2$ and 0.51 Cd/A.

We report here our recent progress in the development and commercialization of polyfluorenes emitting red, green and blue (ROB) colors as materials for light emitting diodes (LEDs). Our patented version of the Suzuki coupling process has been used to synthesize a variety of fluorenebased homopolymers and copolymers emitting colors across the entire visible spectrum. The optical and electronic properties of the polymers are tailored through selective incorporation of different aromatic units into the polyfluorene backbone. Our latest green emitter, reported herein, provides very efficient devices with a low turn-on voltage of 2.25 V, a peak efficiency of 10.5 Cd/A at 6,600 Cd/$m^2$ at 4.85 V. These devices maintain an efficiency of greater than 10 Cd/A up to 50,000 Cd/$m^2$ and demonstrate very good stability as exemplified by a device half-life of greater than 1,500 hours starting from 1,100 Cd/$m^2$. Considerable progress has also been made with red and blue emitters and will be the subject of this presentation.

Transposed scan is an innovation that paves the road to ultra-slim CRTs with deflection angles up to 135$^{\circ}C$ We discuss the integration of video transposition with the other video processing functions in the television set. An in-place transposition algorithm which minimizes the amount of frame memory is proposed as a low-cost solution for transposed scan conversion. The difference in visual perception of transposed scan and normal scan depends on the frame rate and the line density of the video format. We found that for high frame rates and high line densities, no difference was perceived for both scan modes.

The F!T tube is a new type of CRT without a shadow mask. Correct color reproduction is performed by an electronic system that measures the landing positions of the electron beams and corrects through a dedicated deflection system. This paper describes in detail the position sensor and some of the electronics needed to build a functional control system. The principle has been shown in single- and triple-beam 17" and 32" tubes, of which results are included.

The deformation behavior of the frame for tension mask CRT is investigated by experiments and finite element method. We calculate and measure the stress-strain relation at the stress concentrations. The endurance test at 100$^{\circ}C$ was performed for checking tension decrease with time.

Several innovations for reducing the bulkiness of glass bulbs for flat and large CRTs have been made and further technologies are being developed by using material and structural approaches. The integrated glass technology based on these innovations will provide a lightweight shallow glass bulb for the realization of a half- depth CRT.

CRTs can be improved by means of magnetic quadrupoles. Areas of improvement are convergence, spot shape, image-flatness and space charge compensation.

Emissions of thermionic cathodes and field emitters were studied using a cathode emission profiler which works based on the anode scanning method. Findings about impregnated cathodes in thermal activation and gas poisoning processes are shown. Effects of surface treatments for field emitters are studied from the viewpoint of emission profiles and characteristics of the emitters.

Within LG.Philips Displays electron gun assembly different grid alignment methods are used. Besides the commonly used mandrel alignment of grids (Inner Reference System, IRS), also a unique Outer Reference System (ORS) is used as grid alignment method in high-end gun assembly. This alignment method combines alignment accuracy with maximum electron optical design freedom and maximum flexibility in electron gun production.

Mitsubishi Electric Corporation has marketed a series of multimedia CRTs enabling bright picture windows in a high-resolution date display screen. The key components of the multimedia CRTs named Diamondtran $M^2$ are a high-gm (low drive-voltage) electron gun and an aperture grille mask. A high-gm electron gun has been developed by designing a beam forming region with high-gm configuration combining with a high current-density cathode. The development of next generation high-gm guns are also introduced

The electron beam simulation technology is indispensable for the recent electron gun design. The technology is becoming more and more important for deflection yoke (DY) design and investigation of the interference effects between gun and DY. Further, it may become vital even for shadow mask, glass funnel, exposure lens and magnetic shield.

We report our CAB system on thermal analysis for mould designer who is not expert of numerical simulation. Our mathematical model of thermal analysis is axi-symmetrically. It has an automatic mesh-generator that is based on Delaunay method, by using CAD data. And boundary conditions are also fitted automatically.

Yoke simulator has been made for understanding beam movements in the deflection fields of the CRT. Consisting of the modeler, solver and post-processor, the simulator makes yoke model (conventional and rectangular yoke) and calculates charge sources and magnetic filed by BEM (boundary element method). This system supports a number of charge elements (line and surface charges) and beam movements can be predicted by the system.

The spherical aberration and optical integer (f) of the electron gun's main lens in color CRT is obtained, using electron beam trajectory. A spherical aberration is obtained from the relation between the object plane and the image of a beam trajectory. To analyze beam profile, 3rd and 1st order coefficient were obtained and used. It is shown that, in practice, they are applied to electron gun design.

We have studied on response time of the fringe-field switching (FFS) TFT-LCD using the LCs with negative dielectric anisotropy related to rubbing angle. Simulation and experimental results shows that when a rubbing angle approached $45^{\circ}$, a slope of voltage-dependent curve is decreased such that the operation voltage is increased, however the whole response characteristic between inter-gray levels have a trend to be fast.

In this paper, we propose a novel method to form polymer walls without accurate alignment of photomask. The method can be used to form polymer walls in reflective LCDs.

We found that polyimide surfaces bombarded by a low energy argon ion beam align liquid crystals. The pretilt angle of the liquid crystals is controlled by ion beam parameters, such as the energy of the incident ions, the angle of incidence, exposure time and current density. The alignment direction of liquid crystal on substrates corresponded to ion beam direction. By argon ion beam the pretilt angle of the liquid crystals was controlled between $0.5^{\circ}$ and $4^{\circ}$for SE-3140 under the proper conditons. By the atomic force microscope (AFM), polyimide surfaces before and after bombarded by ion beam are compared.

In In order to develop liquid crystal mixtures of high response time and high nematic-isotropic transition temperature ($T_{NI}$) for LCD-TV application, novel liquid crystal molecules with a fluoroisothiocyanate moiety were synthesized. They showed remarkably high $T_{NI}$ over 200 $^{\circ}C$, wide mesophase range of 170 $^{\circ}C$, high dielectric anisotropy of 14 and high optical anisotropy of 0.19. New LC Mixtures of the high $T_{NI}$ (85${\sim}$100 $^{\circ}C$) and fast response time (8${\sim}$10ms) were blended with the novel fluoroisothiocyanate containing LC molecules, phenylcyclohexanes, bicyclohexanes and ester compounds. It was also studied on optimum pitch of liquid crystal for high speed twisted nematic LCD-TV applicaton. The LC mixtures show a fast speed of the below one frame rate in real 17" TV panel.

We have studied electro-optic properties and layer deformations in the smectic phases of 4-(6ethoxy-l-trifluoromethyl-hexyloxycarbonyl)-phenyl-4-Nonyloxybiphenyl-4-carboxylat ( TFMEOHPNBC ) having fluorine attached to one of its benzene rings by electro-optical and small angle x-ray scattering techniques. 3 and 5${\mu}m$ thick test cells were prepared using beryllium plates to minimize x-ray beam absorption. Layer structure and orientation was studied while changing the amplitude and frequency of the applied electric field as a function of cell temperature. We observed that the chevron layer tilt angle is reduced and layer spacing is increased as stabilizing in antiferroelectric phase. This result is extraordinary that there is dimerization in antiferroelectric phase. We also found that there is a threshold electric field that changes the chevron structure to bookshelf structure. This threshold electric field depends on the frequency and temperature as shown in Fig.1. We will discuss the dynamics of layer orientation as determined from the x-ray, electro-optic and dielectric spectroscopy.

We have studied dielectric properties in the smectic phases of 4-(6-ethoxy-1-trifluoromethyl-hexyloxycarbonyl)-phenyl-4-Nonyloxybiphenyl-4-carboxylat ( TFMEOHPNBC ) having fluorine attached to one of its benzene rings. Homogeneous and homeotropic 1.5 and 5${\mu}m$ thick test cells were prepared to analyze molecular dynamic property. We measured capacitance as a function of temperature in the frequency range between 20 Hz and 100 kHz by using HP4284A LCR meter. We observed that the homogeneous cell has high dielectric constant causing dipole moment in smectic $C^{\ast}$ phase, but we can see the dipole moments are canceled out in antiferroelectric phase. It is found that there are two kind of the relaxation director fluctuation below 100 kHz. The first is ionic or space charge contribution below 10 Hz, and the second is Goldstone mode near 1-2 kHz. We will discuss molecular dynamics in smectic phase from extra information such as x-ray and electrooptic data.

New driving waveform which can be inferred by analyzing fundamental LC mechanism is suggested. The main idea of the new waveform is the stabilizing LC layer fast in the cell by controlling the middle director of LC layer. Consequently, we can get not only numerical reduction of optical response merely but also the change of dynamic transmittance from applied voltage exactly

In this paper, we investigated dynamic behaviors of liquid crystal director profiles by simulating two different modeling equations based on vectorial and tensorial approaches. By performing 3-dimensional simulation for a unit pixel, we found that the simulation results from the each of modeling equations lead to different motional behaviors of liquid crystal directors around the disclination line. This is due to the fact that the vectorial approach has a physically meaningless sign of liquid crystal director ${\overline{n}}$. Consequently, it is clarified that the tensorial approach gives more realistic behaviors for the rotation of the directors around the disclination line when the voltages were removed since it maintains nematic symmetry that gives an equivalence of ${\overline{n}}$ and its opposite - ${\overline{n}}$.

Retardation liquid crystal films with a profiled titled optic axis (splay films) of both nematic and discotic types are used as compensation films for twisted nematic displays (TN-LCD). A new method is developed to characterize retardation vs. inclination (retardation profile) of splay films by three parameters: "full retardation" $d^{\ast}{\triangle}n$, "inplane retardation" $R_0$ and "retardation difference" $R_d$ . Splay films with the same retardation profile but with different tilt profile (retardation invariants) are discovered. Splay films with different structure parameters but belong to the same retardation invariant have the same compensation opportunities for TN-LCD.

Characteristics of holographic polymer dispersed liquid crystal(HPDLC) were studied according to various matrix materials to improve the electro-optic properties. Various types of polyurethane acrylates (PUAs) have been designed and synthesized. The morphologies of these gratings were measured by atomic force microscopy(AFM) and electro-optic properties were obtained with UV-visible spectroscopy. Real time measurements of grating fabrication have been obtained according to PUA structures. High reflection efficiency was obtained by modifying the molecular structure.

If an antiferroelectric liquid crystal (AFLC) cell is set between crossed polarizers for optical modulators or displays, it has low transmittance efficiency. This happens because AFLC materials have inherent tilt angles of typically $18^{\circ}{\sim}38^{\circ}$, not $45^{\circ}$. To improve the low transmittance efficiency, we propose a new optical configuration for antiferroelectric liquid crystal displays, which also improves color dispersion.

New banana-shaped achiral compounds, 1,3-phenylene bis [4-{4-(7-octenyloxy)phenyliminomethyl}benzoate](PBOEB), 1,3-phenylene bis [4-{3-fluoro-4-(7-octenyloxy)phenyliminomethyl}benzoate] (PBFOEB), 1,3-phenylene bis [4-{4-(10-undecyloxy)phenyliminomethyl}benzoate](PBEUB), and 1,3phenylene bis [4-{3-fluoro-4-(10-undecyloxy)phenyliminomethyl}benzoate](PBFEUB) were obtained by general synthetic methods. PBOEB and PBFOEB having the octenyloxy groups such as $-(CH_2)_6CH=CH_2$ showed ferroelectric switching, and their values of spontaneous polarization on reversal of an applied electric field were 120 nC/$cm^2$ and 225 nC/$cm^2$, respectively. PBEUB and PBFEUB having the undecyloxy groups such as $-{CH_2)_9CH=CH_2$ showed antiferroelectric switching, and their values of spontaneous polarization on reversal of an applied electric field were 120 nC/$cm^2$ and 140 nC/$cm^2$, respectively. We could obtain ferroelectric and antiferroelectric phases by controlling the number of carbon atom in alkenyloxy chains of bent-core molecules.

We reported the algorithm of driving scheme that enhances moving picture property by improving gray-to-gray response time. Here, we report result of simulation for estimation of driving voltage to reduce response time, and experimental result. We investigated optimization of algorithm so that minimum size of LUT can support to reducing the gray-to-gray response time within 1 frame period, and with single algorithm it is possible to apply the algorithm to various kinds of LC material. So in our system there is no external EEPROM.

We demonstrate the wide-viewing characteristics of a twisted nematic liquid crystal display (LCD) with self-formed micro-domains through the topographical alignment and fringe field effects of dielectric surface gratings (DSG). The mutual optical compensation between micro-domains within each pixel eliminates the contrast inversion phenomenon of TN mode without complex surface treatments.

On the half area of a pixel, pretilt angle was decreased by UV radiation and two domain TN was induced by the pretilt difference. In this structure, ITO slit was made inside pixel electrode on the TFT substrate to stabilize domain boundaries. The result shows that this structure is more resistant to outside stress and unwanted domain deformation is prevented.

We report viewing angle characteristics of the Ultra-FFS TFT-LCD. The FFS mode is known to exhibit both a wide viewing angle and high transmittance, owing to the approximated in-plane rotation of the LC director. Nevertheless, in the bright state, the device shows bluish and yellowish color parallel and perpendicular to the LC director at off-normal directions since the LC director rotates onl.v in one direction, and in addition, the grey scale inversion exists in large oblique viewing angle. However, the Ultra-FFS shows no grey scale inversion and no color shift in wide viewing angle range.

A new type of LCD has been developed using recently developed phase separated composite film method with a single glass substrate. The resultant structures are made of adjacent parallel layers of liquid crystal and polymer. The LC layer is confined between the solidified polymer layer and glass substrate. The electra-optical properties of the display have been investigated. This technique has the potential to realize a lightweight display for hand-held portable electronic products.

We report on an analog electro-optic effect in a nonchiral smectic C (NSC) liquid crystal (LC) mode with negative dielectric anisotropy in a transverse electrode configuration. Two-dimensional numerical simulations are executed to evaluate the display performances. The analog gray scales in the NSC LC mode are obtained in a dielectrically driving scheme.

Three-ring types liquid crystalline compounds having fluoro and isothiocyanate substituent were synthesized and their physical and electro-optical properties were measured to evaluate the applications to active matrix VA liquid crystal displays. The tetrakis(triphenylphosphine)palladium(0) catalyzed cross coupling of aryl boronic acids with aryl halides is used to prepare trans-4'-Alkoxy-2,3-difluoro-3'-isothiocyanato-4-(4-alkylcyclohexyl}-biphenyl series. The synthesized compounds showed the nematic liquid crystalline phase and the negative dielectric anisotropy. The prepared mixtures showed faster response time and lower threshold voltage than their host mixture.

VA-LCDs is widely used for recent LCD productions owing to good viewing angle and high contrast. To apply for VA-LCDs, we have synthesized novel homeotropic alignment materials, which all generated high pretilt angles ($9^{\circ}$). The thermal stabilities of them were observed by thermogravimetric analysis (TGA). Transmittances of the NLC cell used the new alignment material were not changed before and after thermal annealing at $120^{\circ}C$ for 24hrs. In this work, the synthesis and alignment properties of new homeotropic alignment materials will be reported.

Benzylideneacetophenones are known as chalcones[1]. The chalcone has been known to be a photo-isomerizable and photo-dimerizable chromophore. The chalcone derivatives were prepared by base-catalyzed condensation of aldehydes and acetophenones, which were substituted with various alkyl chains. The synthesized chalcone was introduced into the t-BOC protected diamine through William synthesis reaction. Photocrosslinkable polyimide was prepared via one-step imidization reaction of DOCDA (5-(2,5-dioxotetrahydro furyl}-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride) and the chalcone introduced diamine using isoquinoline (5 wt%) in m-cresol. The polyimide solutions were spin-coated onto the quartz, silicone wafer and glass substrates and the obtained thin films were irradiated obliquely with linearly polarized UV light.

Tree-ring types liquid crystalline compounds having fluoro and isothiocyanate substituent[1] were synthesized and their physical properties were measured to evaluate the applications to TFT-LCD TV. All synthesized compounds were showed remarkably high Tni point. Birefringence(${\triangle}n$) and dielectric anisotropy(${\triangle}{\varepsilon}$) were higher than fluoro analogues and isothiocyanate substituted bicyclohexyl-phenyl compounds.

In this paper, we report a novel way to evaluate the anticlinic interlayer coupling coefficient U between smectic layers of an antiferroelectric liquid crystal, by utilizing a small field-induced perturbation of the molecular orientation. U was found to exhibit an unusual "S-shaped" dependence on temperature, with values ranging between $0.4{\times}10^4$ and $0.4{\times}10^{-1}$ erg $cm^{-3}$ over a 10$^{\circ}C$ temperature range below smectic A-smectic $C_A$ phase transition temperature. The results are good agreement with estimates for U based upon the threshold field for the onset of solitary waves, and provide strong supporting the low-field regime for the single Fourier component model.

Liquid chromatographic direct resolution of racemic naphthyl propionate liquid crystals were successful on a commercial chiral column, (S,S)-Whelk-O1. The very simple procedure can be applied to the intermediate and final products without any structural modification.

The influence of isomeric state of doped azo dye on the $B_7$ phase of bent-shaped liquid crystal (LC) is studied. It was found that modulating the isomeric trans-cis state of azo dye can change the molecular arrangement of the bent-shaped LCs. To identify these phenomena the observations of microscopic texture, electro-optic response, second harmonic wave generation (SHG) and switching current were carried out..

In In order to develop liquid crystal mixtures of high response time and high nematic-isotropic transition temperature ($T_{NI}$) for LCD-TV application, novel liquid crystal molecules with a fluoro-isothiocyanate moiety were synthesized. They showed remarkably high $T_{NI}$ over 200 $^{\circ}C$, wide mesophase range of 170 $^{\circ}C$, high dielectric anisotropy of 14 and high optical anisotropy of 0.19. New LC Mixtures of the high $T_{NI}$ ($85{\sim}100 ^{\circ}C$) and fast response time ($8{\sim}10ms$) were blended with the novel fluoro-isothiocyanate containing LC molecules, phenylcyclohexanes, bicyclohexanes and ester compounds. It was also studied on optimum pitch of liquid crystal for high speed twisted nematic LCD-TV applicaton. The LC mixtures show a fast speed of the below one frame rate in real 17" TV panel.

In this paper, we demonstrate the deformation of TFT-LCD panel using numerical analysis based on the finite element method. To make better uniform cell gap and less stress at a photo-definable spacer (spacer), we have investigated process and design factors such as amount of liquid crystal (LC), spacer density, area, height, and material property. Furthermore we optimized design factors and achieved the robust design through the simulation.

We investigated electro-optic and ionic properties of twisted nematic cells by using control of chiral pitch. These properties are observed in practical experiment and simulations. C-V and V-T curve characteristics were obtained from three types of cells with d/p. It is shown that d/p ratio of short cells exhibit faster response time improved by 20% than normal cell. Also, inter-gray response time is improved each rise time and decay time. And, the increase of saturation voltage is happened because of the small twist angel change from initial state at high voltage near 5V. To compensate for longer black level tail, gamma curve index was varied from g = 2.2 to g = 2.7 in module status. Additionally, adding chiral dopant into TN cells improved ionic characteristics such as increasing VHR, Ion density and DC Hysteresis were decreased..

We studied the liquid crystal (LC) alignment capabilities and the generation of pretilt angles with ion beam exposure on a diamond like carbon (DLC) layer. A high pretilt angle of 3.5$^{\circ}$ with ion beam exposure on the DLC layer can be obtained. A high pretilt angle in NLC by ion beam alignment method on the DLC layer can be achieved.

Electro-optical characteristics of new multi-domain vertical-alignment (MVA) liquid crystal displays (LCDs) with negative dielectric anisotropy on a homeotropic photopolymer were studied. Good voltage-transmittance (V-T) curves by the new MVA-LCD on the homeotropic photo-polymer were obtained. Also, the stable response time of MVA-LCD on the homeotropic photopolymer can be achieved. The viewing angle of the new MVA-LCD could be improved by the grating groove with UV exposure and development on the photo-polymer.

In this paper, we demonstrate the impact of oxide interface-state on low temperature poly-Si TFTs. The TFTs with interface-state exhibit poor performance and serious degradation under hot carrier and gate bias stress. Our results indicate that the worse oxide integrity cause initial characteristic shift and device instability.

In this paper, we analyze the impact of plasma etching process induced device degradation on low temperature poly-Si TFTs. The results indicate the relationship between device degradation and PPID effect during plasma fabrication. The dual-gate structure, which is used to suppress leakage current, is also discussed in this research.

The poly-Si thin film can be used in high mobility active matrix liquid-crystal display (AMLCD) and system on panel (SOP). In this paper, poly-Si thin films were grown by novel high temperature process on the molybdenum (Mo) substrate. By applying a high current above 48A on a Mo substrate. We obtained an improved crystalline Si films with the crystallinity over 80%. We exhibit the properties of structural and electrical properties of high temperature poly-Si thin film transistor on the Mo substrates.

Various fluoride films on a glass substrate were prepared and characterized in order to determine the best seed layer for a microcrystalline silicon (${\mu}c$-Si) film growth. Among the various group-IIA-fluoride systems, the $CaF_2$films on glass substrates illustrated (220) preferential orientation and a lattice mismatch of less than 0.7% with Si. $CaF_2$ films exhibited a dielectric constant between $4.1{\sim}5.2$ and an interface trap density ($D_{it}$ as low as $1.8{\times}10^{11}\;cm^{-2}eV^1$. Using the $CaF_2$/glass structure, we were able to achieve an improved ${\mu}c$-Si film at a process temperature of 300 $^{\circ}C$. We have achieved the ${\mu}c$-Si films with a crystalline volume fraction of 65%, a grain size of 700 ${\AA}$, and an activation energy of 0.49 eV.

We have developed a low-power, high slew-rate OP-AMP for large size and high resolution TFT-LCDs which have 8${\mu}$A quiescent current with settling time less than 6${\mu}$sec. The proposed OP-AMP contains newly developed the driving circuit of class-AB output stage which can achieve a low quiescent current less than 8${\mu}$A and a slew-rate higher than 3.14V/${\mu}$sec.

Electrode formation methods such as a metal-taping, a electrolytic plating, and a metal-paste melt-bonding, are introduced for an external electrode fluorescent lamp. The characteristics of luminance and efficiency for various external electrode types have been investigated.

Various types of switching inverters such as a full-bridge, a half bridge, a push-pull, and a multi-vibrator, are introduced for multi-lamps backlighting with EEFLs and CCFLs. Synchronizing the phase between voltage and current waves, a high luminance and a high efficiency have been achieved.

A self-discharge in multi-EEFLs and CCFLs has been found to provide a high luminance and efficiency. With a fast rising and falling times of $2{mu}s$, and the peak voltage over 1.6KV, the self-discharge occurs in EEFLs and CCFLs driven by a full bridge switching inverter. Particularly in CCFLs connected with a typical value of ballast capacitance, a self-discharge follows by the main discharge when the voltage falls to the ground.

The reflective liquid crystal(LC) imager in one panel Liquid Crystal on Silicon(LCoS) System must have the properties such as fast response time, high contrast ratio(C/R) and voltage holding ratio(VHR) which are more related to the lifetime of imager than the others. As the high-output light including a short wavelength from UHP lamp is exposed to LCoS imager, the indium metal impurities, which decrease the C/R and VHR, are diffused from ITO thin film on glass. To ensure the high reliable LCoS imager for HD projection TV, we have studied the effects of the plasma treatment on ITO film to reduce impurities in imager.

The antiferroelectric liquid crystal display (AFLCD) is unique display that can show the perfect moving image using the passive matrix driving scheme. We optimized the driving waveform and introduced the dual driving method. Also, by improving this driving method and using line inversion method, we realized AFLC display with high image quality, which has 160(RGB)${\times}$240, 32768colors, crosstalk free and flicker free. The contrast ratio is greater than 60:1, and the brightness is above 200cd/$m^2$.

The crystallization of amorphous silicon (a-Si) was achieved using a field aided lateral crystallization (FALC) process at 350 $^{\circ}C$. Under the influence of an electric field, Cu is found to drastically enhance the lateral crystallization velocity of a-Si. When an electric field was applied to the selectively Cu-deposited a-Si film during the heat treatment at temperature as low as 350 $^{\circ}C$, dendrite-shaped crystallization of a-Si progressed toward Cu-free region and the crystallization from negative electrode side toward positive electrode side was accelerated. We identified that 1000${\AA}$ thick a-Si film was completely crystallized by Cu-FALC process at 350 $^{\circ}C$ by TEM analysis.

In order to achieve higher performance and low cost a-Si TFT-LCD panel, new material architecture and its process integration for a-Si TFT array manufacturing method were developed. Material combination of low resistant dry-etchable metal and new pixel electrode under currently adopted 4 mask process made it possible to get more-simplified manufacturing method and better device performance for the a-Si TFT-LCD application. Proposed 4 mask process architecture with optimized wet etchants and dry etching process was applicable to various devices such as notebook, monitor and TV.

We designed a low cost optical structure of transflective LCD that uses only a half number of retardation films compared to general active matrix transflective LCD. The prototype embodied by this design shows reasonable reflective and transmissive performance. This design would provide us thinner, lighter and cheaper product due to its reduced retardation film structure.

The liquid crystal(LC) pixel capacitance Clc, which varies as a function of applied pixel voltage, is a main factor of pixel voltage errors on input gamma voltage, and therefore of the electro-optics(E-O) characteristics of LC pixel for a-Si TFT LCDs. The pixel voltage error(${\Delta}$Vp) for input gamma voltage was simulated for 14.1 inch diagonal XGA panel. An agreement between the experimental results and simulation was satisfactory for the gamma voltage compensation, ${\Delta}$Vp of the input gamma voltage. The proposed compensation method was successfully introduced to a 14.1 inch diagonal XGA panel, and a remarkable improvement of image sticking was achived.

We investigated to decrease the leakage current of SiNx film by employing $N_2$ plasma treatment. The insulator layers were prepared by two step process; the $N_2$ plasma treatment and then PECVD SiNx deposition with $SiH_4$, $N_2$ gases. To prove the influence of the $N_2$ plasma treatment, the Si substrate was exposed to the plasma, which was generated in Ne gas ambient. Without plasma treatment SiNx film grow at the rate of 7. 03 nm/min, has a refractive index n = 1.77 and hydrogen content of $2.16{\times}10^{22}cm^{-3}$ for $N_2/SiH_4$ gas flow ratio of 20. The obtained films were analyzed in terms of deposition rates, refractive index, hydrogen concentration, and electrical properties. By employing $N_2$ plasma treatment, interface traps such as mobile charges and injected charges were removed, hysteresis of capacitance-voltage (C-V) disappeared. We observed plasma treated sample were decreased the leakage current density reduces by 2 orders with respect to the sample having no plasma treatment.

The LVDS (Low Voltage Differential Signaling) I/O cells, fully compatible with ANSI TIA/ EIA-644 LVDS standard, are designed using a 0.35${\mu}m$ standard CMOS technology. With a single 3V supply, the core cells operate at 1.34Gbps and power consumption of the output driver and the input receiver is 10. 5mW and 4.2mW, respectively. In the output driver, we employ the DCMFB (Dynamic Common-Mode FeedBack) circuit which can control the DC offset voltage of differential output signals. The SPICE simulation result of the proposed output driver shows that the variation of the DC offset voltage is 15.6% within a permissible range. In the input receiver, the proposed dual input stage with a positive feedback latch covers rail-to-rail input common-mode range and enables a high-speed, low-power operation. 5-channels of the proposed LVDS I/O pair can handle display data up to 8-bit gray scale and UXGA resolution.

We propose modified concept that enables LCDs quasi-impulsive operations, and demonstrated a prototype AM-LCD that is suitable for displaying moving pictures combined with '2-Domain Half-V shaped switching mode' FLCD.

In this work, the electrical characteristics of organic thin film transistors with the surface-treated organic gate insulator have been studied. For the surface treatment, the photoalignment technique was used. The field effect mobilities of the devices with PVP gate insulator was improved about ten times as high as those of TFTs without the insulator surface treatment.

We developed three kinds of electrode-structures for high luminance and luminous efficiency. Also, we optimized the mixture gas. Three kinds of 7.5-inch experimental panels having a pixel pitch of 0.864mm were evaluated, and high efficiency of 1.6lm/W was obtained in the panel type2.

The effects of phosphor properties such as the granular sizes and shape on the crosssectional shape of phosphor layer and plasma discharge characteristics for improving the luminance and luminous efficiency in ac PDP have been investigated. As the granular size decreases, the thickness of vertical side of barrier rib in blue cell decreases, and wheras the thickness of bottom side increases due to increased dispersibility. In addition, the phosphor with round granular shape showing good dispersibility shows better voltage margin and higher luminous efficiency due to their improved discharge volume and packing density.

The Ultra Violet(UV) emission characteristics of Neon + Nitrogen gas-mixture discharge was investigated in AC plasma display panel. The firing voltage of Ne+$N_2$ gas-mixture discharge increased with increasing nitrogen concentration. The UV intensity emitted from the gas discharge also increased with increasing nitrogen concentration. The UV efficiency increase with increasing $N_2$ partial pressure at low $N_2$ concentration, and then UV efficiency is saturated at high $N_2$ concentration.

Using two- and three-dimensional fluid simulation codes, we have suggested several new plasma display panel (PDP) cell structures that have high luminous efficiency compared with conventional structure. To improve the luminance and discharge efficiency, we utilize long discharge path, lower electric field region, and reduction of power consumption by adding one auxiliary electrode or reducing the electrode area. Consequently, luminous efficiency increases about 1.8 times. Furthermore for the resonance radiation trapping effect in PDP system, we have described a self-consistent radiation transport model coupled with fluid simulation using modified Holstein's equation.

We studied the effect of secondary electron emission from the back plate of AC-PDP, on the ramp waveform driving of the system, using two-dimensional PDP cell discharge simulator. It is found that the secondary electron emission from back plate plays a significant role in getting a stable weak discharge during the ramping up of X-Y electrode voltage. This is because grounded address electrode acts as a cathode during the setup of surface charge, and the secondary electron emission from phosphor in the back plate must be large enough to accumulate surface charges on the dielectric layers without strong plasma discharge. We have concluded that the secondary electron emission coefficient(${\gamma}$) of phosphor, besides MgO, must be known to understand the characteristics of the PDP system. A few suggestions for improvement of the system is also made and tested.

To improve the luminance and efficiency of AC PDP, the effects of a square pulse applied to the address electrode during a sustain-period is investigated. Through this experiment, we confirmed the improvement of luminance and efficiency. We performed the temporal behavior measurement for the light emitted from AC PDP at floating state of the address electrode and at various auxiliary voltages (including ground state) applied to the address electrode using the scanned point detecting system. In the case of using an auxiliary voltage pulse, emission starts at the inner edges of the anode and cathode simultaneously. Also, we obtained the larger two discharge volumes compared with the normal sustain discharge where address electrode is floated.

We propose modified fence electrode structure for manufacturing of ITO-electrode-free PDP. Luminance, luminance efficiency and addressing time for the proposed structure shows performance improvement about 25 percent. Our results can be used for the reduction of manufacturing cost without degradation of PDP performance.

This paper proposes a real-time wall charge measurement circuit for three-electrode AC PDP. It includes a charge-compensation network, current-integrating capacitors, initializing switches, and an op-amp. With this equipment, we measure the wall charge variations for the effects of sustain voltage, sustain pulse width, sustain frequency, and neighboring cells.

A new reset waveform is proposed for reducing the reset period. A square pulse is applied to the address electrode while reset pulse ramps and before a discharge between the sustain electrodes occurs. The square pulse induces a discharge between the address electrode and the X electrode, and the induced wall charge is opposite to the applied ramp pulse. Thus, the next discharge between the sustain electrodes becomes weaker. The weaker discharge lowers background luminance and improves contrast ratio. Thus, the new reset waveform can reduce ramp up time in the ramp reset waveform The experimental results show that the ramp up time can be reduced by about 90% compared with the conventional ramp reset waveform.

Luminance and contrast ratio is one of the most fundamental and important parameters of plasma display panel. Understanding the effects of cell design parameters on the display and background luminance is inevitable for improving the contrast ratio. We report the experimental results on the relationships between cell parameters and contrast ratio of the ac PDP driven by ADS scheme. It was found that the contrast ratio is the most significantly affected by rib height and optimum range of the rib height simultaneously affects the facing discharge during the reset periods, diffusion loss of plasma and shadowing of the visible light emitted from phosphor.

Quantitative analysis of dynamic false contours on PDP is essential to evaluate the performance of algorithms for false contour reduction. It also serves as an optimization criterion for selecting the subfield pattern. In this paper, a color difference in uniform color space is defined as a new measure for dynamic false contours. Unlike the measures in previous works, it accounts for the channel dependencies among the RGB color channels.

In this study, outgassing characteristics of MgO films, and the plasma cleaning effects of the deposited MgO films by atmospheric pressure plasma on outgassing rate were compared. The MgO layer was heated up to 350 $^{\circ}C$ and the outgassing characteristics were observed for the heated conditions. As the main impurity species $H_2,\;H_2O,\;N_2,\;CO_2,\;and\;H_2O$ were released from this panel. Impurity species of plasma treatment panel were lower than non-treated panels for the heating temperature

MgO thin films were deposited on glass and (100) Si substrates by an Arc Ion Plating (AIP) equipment using a magnesium metal target at various oxygen gas flow. In this work, we investigated the relationship between the structural properties and the discharge characteristics of MgO coating layers. X-ray diffraction and AFM have been used to study behaviors of the structure and surface morphology. The optical transmittance and the ion induced secondary electron emission coefficient of the MgO films have been also measured. The resistivity of the deposited MgO films was gradually increased from 0.17 G ohm/${\square}$ to 0.35 G ohm/${\square}$ with the oxygen gas flow. The growth rate of the MgO coating layer was decreased with increasing the oxygen gas flow, while the optical transmittance was improved.

$Al_2O_3$ capping layer and MgO protective layer were deposited by electron beam evaporation method using single crystal source. Thickness of the capping layer, $Al_2O_3$, was varied from 5 nm to 10 nm. Surface morphology was observed by SEM and AFM before and after hydration. And microstructure of deposited $Al_2O_3$ layer and chemical shift of electron binding energy were also observed by high resolution TEM and XPS, respectively, after hydration. From these results, it was found that Mg atoms diffused into $Al_2O_3$ layer, reacted with moisture and formed $Mg(OH)_2$ during hydration. As thickness of $Al_2O_3$ increased, extent of hydration increased. $Al_2O_3$ capped MgO thin films and uncapped MgO thin films were deposited on AC-PDP test panel to characterize discharge properties. Although $Al_2O_3$ has poor discharge properties rather than MgO, because of many hydrated species on the surface of MgO, similar discharge properties were observed.

Transparent dielectric layer having color-filter function in front panel for PDP(Plasma Display Panel) was successfully fabricated and characterized. Transparent dielectric layer in front panel was made of glass based on $PbO-SiO_2-B_2O_3$ ternary system. The change of properties with content variation of oxide colorants in transparent dielectric layer having color-filter function was systematically accessed. It was demonstrated that the optimized content of oxide colorants to parent glass could greatly increase up contrast ratio and color temperature without significantly degrading luminance.

In $ABCO_4$ and $ABC_3O_7$ (A=Ca, Sr; B=Y, Rare earth; C=Al, Ga), random distribution of static crystalline fields in activator sites results in inhomogeneous broadening of spectral lines of luminescent materials. In this study, we investigated luminescent properties of above-mentioned materials by excitation and emission spectra. In result, both $ABCO_4$:Tb and $ABC_3O_7$:Tb phosphors emit the green light. $ABC_3O_7$:Tb phosphors absorbed shorter wavelength energy than $ABCO_4$ phosphors so that the emission efficiencies of $ABC_3O_7$:Tb phosphors were higher than those of $ABCO_4$:Tb phosphors under vacuum UV.

A new PDP barrier rib formation technique was investigated utilizing transparent soft maid made of silicon resin. Transparent soft mold was fabricated by pouring a silicone resin into the base mold made with photosensitive glass. The photosensitive barrier rib paste was coated on the glass substrate and dried in a 90 $^{\circ}C$ convection oven for 20min. The transparent soft mold was pressed on top of the semi-dry barrier rib layer and then irradiated with a UV lamp to a total dose of $900{\sim}1000mJ/cm^2$ The soft maid was then removed from the pressed barrier rib by winding up and fine pattern of barrier rib was obtained. The photosensitive barrier rib paste makes the demolding easy due to reduced interfacial forces and shrinking of paste materials.

Sealing of two glass plates composing of PDP panel was done in a vacuum chamber by using an auxiliary heating line(AHL). In order to improve the uniformity of sealing temperature and reduce the panel temperature during sealing, the AHL was introduced by a screen printing method inside a frit glass and used as a part of heating source for the frit melting. By using the AHL technology and the specially prepared frit glass, we have successfully sealed a PDP test panel without bubbles and any leak through the frit glass.

A lateral type GaN field emission diodes were fabricated by utilizing metal organic chemical vapor deposition (MOCVD). In forming the pattern, two kinds of procedures were proposed: a selective etching method with electron cyclotron resonance-reactive ion etching (ECR-RIE) or a simple selective growth by utilizing $Si_3N_4$ film as masking layer. The fabricated device using the ECR-RIE exhibited electrical characteristics such as a turn-on voltage of 35 V for 7 ${\mu}m$ gap and an emission current of ${\sim}580$ nA/10tips at anode-to-cathode voltage of 100 V These new field emission characteristics of GaN tips are believed to be due to a low electron affinity as well as the shorter inter-electrode distance.

We carried out 2-dimensional numerical calculations of electrostatic potential for triode field emitters with planar cathodes using the finite element method. As it turned out, the conventional triode structure with a planar cathode suffered from large gate current and wide spreading of emitted electrons. To circumvent these shortcomings, we proposed a new triode structure. By simply inserting a conducting layer of proper thickness on top of the cathode layer, we were able to modify the electric field distribution on the cathode surface so that low gate current and electron-focusing effect were achieved, simultaneously.

The carbon nanotube emitters for field emission displays were fabricated by screen printing techniques. The pastes for screen printing are composed of organic binders, carbon nanotubes, and some additive materials. Then the pastes were printed on Cr-coated/Ag-printed soda-lime glass substrates. From the I-V characteristics, the turn-on field of SWNT was lower than that of MWNT. The decrease in the mesh size of screen masks resulted in decreasing the turn-on field and increasing the electron emission current. When the carbon nanotubes were mixed with glass frit, glass frit appeared to contribute to the vertically aligning of carbon nanotubes on glass.

Chemical species during growth of carbon nanotubes (CNTs) in direct current-plasma enhanced chemical vapor deposition were studied in details using $C_3H_4-NH_3$ and $CO-NH_3$ mixtures through optical emission spectroscopy (OES). In the $C_3H_4-NH_3$ system, the relative intensities of CN (388.3 nm) and CH (431.4 nm) decreased and that of $C_2$ (436 nm) increased, leading to $sp^2$-graphization into the CNT structure, leading to improvement of field emission property of CNTs. In the $CO-NH_3$ system, the trend is completely reversed. Attributing to the atomic oxygen for helping the graphitization of carbon, CNTs could be grown under the flow rate of CO (180 sccm)-$NH_3$ (10 sccm). Through these results, we suggest the growth mechanism in our system.

The growth of carbon nanotubes (CNTs) was carried out using ratio frequency plasma enhanced chemical vapor deposition (rf PECVD) system equipped with dc bias for the directional growth. Acetylene and ammonia gas were used as the carbon source and a catalyst. The relation between gas flow rate and dc bias on the growth of CNTs was investigated. We studied the relation between emission properties and the directionality of CNTs grown under different dc bias voltage.

Vertically aligned carbon nanotubes (CNTs) have been produced using various type of plasma enhanced chemical vapor deposition (PECVD). Catalysts such as Ni, Co, and Fe are used for growth of CNTs. To explain the effect of catalysts on the growth characteristics of CNTs, carbon species of $C_2H_2$ was observed in different catalysts using optical emission spectroscopy (OES) with theoretical calculation on the surface reaction in different catalysts.

We have investigated the catalyst effect on the growth and structure of CNTs using thermal chemical vapor deposition. The respective growth rate of CNTs shows that the performance of catalysts is in the order of nickel (Ni)>cobalt (Co)>iron (Fe). The average diameter of CNTs follows the sequence of Fe, Co, and Ni catalysts. The structure of CNTs reveals almost same morphology regardless of catalyst but the crystallinity of CNTs is largely dependent on catalyst. The crystallinity of CNTs synthesized from Fe catalyst is higher than that from Ni or Co catalyst. We demonstrate that the growth rate, the diameter, and the crystallinity of CNTs can be manipulated by selecting the catalysts.

Vertically aligned CNTs were grown on Fe-deposited $SiO_2$ substrates using thermal CVD of acetylene gas. The size of Fe particle is controlled by the flow rate of $NH_3$ and pretreatment time, which leads to control the diameter of CNTs. As the diameter of CNTs decreases, the growth rate is enhanced with an inverse dependence of the CNT diameter. The growth rate of CNTs increases linearly as the growth time increases until 30 min but is rapidly decreased over 40 min. We found an inverse relation between the diameter and growth rate of carbon nanotubes. As the diameter of CNTs increases, the compartment layers of bamboo-shaped CNTs appear more frequently. A base-growth model is suitable to explain the dependence of growth rate and structure of CNTs on the diameter size of catalytic particles.

Vertically aligned carbon nanotubes(CNTs) have been grown on Ni-coated TiN/Si substrate by microwave plasma chemical vapor deposition using $H_2/CH_4$ mixture gas. We have investigated the Effect of process parameters on the growth of CNT. During the growth, microwave power, pressure, and growth temperature were varied from 300 W to 700 W, 10 Torr to 30 Torr, and 300 $^{\circ}C$ to 700 $^{\circ}C$. respectively. Then we controlled the size of CNTs. The structure of CNT was sensitively dependent on the process parameters.

To investigate thermal effects of silicon field emitter, we fabricated and characterized single silicon tips with various tip radii, which generate different joule heating. Through I-V and stability tests, the changes of emission characteristics and tip structures due to different tip heating were observed and discussed. From the results, we confirmed that the changes of emission characteristics due to thermal effects in silicon emitter could occur at relatively small emission currents and concluded that the thermal effects should be also considered under normal operation condition above 1 ${\mu}A$.

In this paper, it is reported that the anode current changes at the constantly applied gate voltages and the current-voltage (I-V) characteristics of Si, Co silicide and Mo silicide field emitter arrays (FEAs) depending on vacuum level from a $10^{-9}$ torr to a $10^{-6}$ torr. The mechanism of the robustness of anode current degradation of Mo silicide FEAs under poor vacuum conditions can be explained by the model of tolerance for the oxygen adsorption and oxidation at the silicide surface. Also, we present the changes of emitting area and work function of the emitters according to vacuum level.

Well-aligned multi-wall carbon nanotubes (MWCNTs) have been grown on both Coming glass and silicon substrates at about 400 $^{\circ}C$ by a modified plasma - enhanced chemical vapor deposition system. We have investigated laser irradiation effect on carbon nanotube surface by using an ultra - violet laser. The laser operated to modify structural defect of was carbon nanotube and to ablate possible contamination of carbon nanotube surface. The morphology and surface transformation of MWCNTs as analyzed by a SEM. In addition, the field emission measurement was also carried out in a vacuum chamber with a $10^{-7}$ Torr base pressure by applying bias voltages up to 1000V.

Well-aligned multi-wall carbon nanotubes (MWNTs) were fabricated by utilizing a radio frequency plasma-enhanced chemical vapor deposition (rf-PECVD) system from Ni particles at the bottom of anodic alumina nanoholes (AAN). To remove the amorphous graphite layers on the AAN surface and to eliminate the protrusion of MWNT tips, the AAN surface with MWNTs were treated by external rf plasma source. As a result, the AAN surface almost became flat without having any protrusion of MWNT tips. The diameter, length of MWNTs and AAN were investigated by using a scanning electron microscopy (SEM). Raman spectroscopy was also used to characterize wall structure of the carbon nanotube. And the emission properties of the MWNTs were measured for the application of field emission display (FED) in near future.

Growth behaviors of carbon nanotubes (CNTs) are studied in terms of catalyst by using scanning electron microscopy and transmission electron microscope (TEM). Catalyst films deposited on various substrates are agglomerated into nano-islands during the heat-up to the growth temperature. In particular, we focus on the direct investigation of the microstructures of the CNTs and the interface of CNTs-catalyst-substrate using cross-sectional TEM. We investigate relationship to the subsequent CNTs growth on each nucleation site. The growth of CNTs depends on the catalyst itself but not the silicide formation between the catalyst and the substrate.

Porous anodic aluminum oxide(AAO) templates prepared by anodizing method were used for growing multiwalled carbon nanotubes(CNTs). AAO templates with the homogeneous pore diameter and length were obtained by two step anodizing technique. Using AAO templates, vertically well-ordered two-dimensional carbon nanotube arrays were fabricated. We investigated the field emission property of CNTs grown using different catalyst metals in vacuum chamber (<$10^{-7}$ Torr) on AAO Template. To explain the different emission property, the surface reaction between catalysts and alumina pores which inserted carbon species of $C_2H_2$ using High resolution transmission electron microscopy (HRTEM) was studied.

In order to realize full color display, two approaches were used. The first method is the patterning of red, green, and blue emitters using a selective deposition. Another approach is based on a white-emitting diode, from which the three primary colors could be obtained by micro-patterned color filters. White-light-emitting organic light emitting devices (OLEDs) are attracting much attention recently due to potential applications such as backlights in liquid crystal displays (LCDs) or other illumination purposes. In order for the white OLEDs to be used as backlights in LCDs, the light emission should be bright and have Commission Internationale d'Eclairage (CIE) chromaticity coordinates of (0.33, 0.33). For obtaining white emission from OLEDs, different colors should be mixed with proper balances even though there are a few different methods for mixing colors. In this study, we will report a white organic electroluminescent device based on an incomplete energy transfer. In which the blue and green emission come from the same layer via incomplete energy transfer.

We investigated the effect of lithium 8-hydroxyquinolinolatolithium (Liq) as an electron injection layer on the performance of organic light emitting devices (OLEDs) and optimized the device efficiency by varying thickness of Liq layer. The device with 1nm Liq layer showed significant enhancement of the device performance and device lifetime. We also compared $Znq_2$ and LiBBOX with Liq as an electron injection layer.

In order to improve the power efficiency of multi-layer organic light emitting diodes (OLEDs), electron injection into ETL(electron transport layer) from cathode at the interface between ETL and cathode was enhanced by interposing a proper electron injection layer at the interface. The HTL(hole transport layer) and ETL materials used were N, N'diphenyl- N, N' - bis(3-methylphenyl-1, 1'- biphenyl - 4, 4 'diamine (TPD) and tris (8-hydroxyquinoline) aluminum ($Alq_3$) respectively. Cathodes using co-evaporated Al-CsF, Al-KF, and Al-NaF composites are adopted to enhance the electrical and optical properties of OLEDs. OLEDs with alkaline metal-doped cathode show a luminance of as high as 35,000 cd/$m^2$, and external quantum efficiency about 1.35 %. In addition, they show higher power efficiency at all bias conditions and good reproducibility.

Indium tin oxide (ITO) was used as the top anode of top emission inverted organic light emitting diodes (TEIOLEDs). TEIOLEDs were fabricated by deposition of an aluminum bottom cathode, an N,N'-diphenyl-N,N'-bis(3-methylphenyl)-1, 1'-diphenyl-4, 4 1'-diamine (TPD) hole transport layer, a tris-8-hydroxyquinoline aluminum ($Alq_3$) emission layer, and an ITO top anode sequentially. ITO was deposited by r.f. magnetron sputtering without $O_2$ flow during the deposition. After the deposition, the deposited ITO layer was kept under oxygen atmosphere for the oxidation. The characteristics of the TEOILED were affected significantly by the post-deposition oxidation condition.

In this work, the electrical characteristics of organic thin film transistors with the surface-treated organic gate insulators have been studied. For the surface treatment, the simple rubbing technique was used. The field effect mobilities of the devices with PVP gate insulator was improved about four times as high as those of TFTs without the insulator surface treatment.

We report a new red light emitting fluorene-based copolymer, poly{9,9-bis(2'-ethylhexyl)fluorene-2,7-diyl-co-2, 5-bis(2-thienyl-1-cyanovinyl}-1-(2'-ethylhexyloxy)-4methoxybenzene-5",5'''-diyl} (PFTCVB). The synthesized copolymers showed the absorption maxima at about 380 nm and the absorption between 425 and 600 nm increased as the fraction of the thiophene-containing monomer (BTCVB) increased. In PL, the emission maxima of the copolymers were red-shifted as the fraction of BTCVB increased, despite the similar absorption characteristics were shown in the UV-visible spectra. The copolymer containing 15 mol% of BTCVB showed a maximum PL and EL emission at 620 and 630 nm.

2,7-dibromo-9, 9-dialkyl-substituted-fluorene derivatives were prepared by the alkylation of 2,7-dibromofluorene with various alkyl groups under two-phase phase transfer catalysis (PTC) conditions, as monomers for synthesizing poly(dialkylfluorene)s. Tetra-nbutylammonium hydrogen sulfate (TBAHS) was used as a phase transfer catalyst to enhance nucleophilic substitution. In addition, NaOH in water (25M) was used as a base to generate anions. Compared to conventional alkylation using butyllithium(BuLi), the reaction using the PTC technique attained high selectivity and substantial conversion of reactants, due to the enhanced reaction rate, while the reaction was carried out under moderate conditions. An approximately 90% yield was obtained from the reaction and the reaction time was remarkably reduced. 2,7-dibromo-9,9-dihexyl-fluorene, 2,7-dibromo-9,9-dioctyl-fluorene, and 2,7-dibromo-9,9-di(2-ethylhexyl)-fluorene were effectively synthesized by phase transfer catalytic reaction.

For the evaporation process, thickness uniformity is of great practical importance. And, it is commercially significant to improve the efficiency of material of the evaporant which is deposited on the substrate because of high price of organic materials. To achieve the better thickness uniformity and the higher evaporating efficiency, Samsung SDI has introduced the new concept of the asymmetric evaporation technology for depositing evener and cheaper organic layers. Based on the developed method, the uniformity of the organic layer thickness can be successfully controlled. Furthermore, the very high efficiency may allow the OLED displays be manufactured with the lower cost.

By forming lens-like shapes on the electrode surfaces in OLEDs, the external quantum efficiency is enhanced. The external quantum efficiency of the proposed structure can be much more increased compared to that of the flat structure by decreasing the length of major axis and increasing the length of minor axis for the lens-like shapes.

We report on white light emission from a light emitting diode(LED) prepared by blending a red emitting copolymer, m-SiPh PPV-co-MEH PPV, and a blue emitting polyvinylcarbazole (PVK). White light emission was realized when the weight ratio of the m-SiPh PPV-co-MEH PPV : PVK equals to 1 : 30, in which the commission Internationale de L'Eclairage coordinates were x=0.3266 and y=0.3438.

We reported the optical and electrical characteristics of organic electroluminescent phenylamine derivatives. The maximum EL peak of organic electroluminescent devices(OELDs) with PDV-DMI and PDV-AQ are at 615nm and at 592nm which are corresponding to red and orange emission, respectively.

We reported the possibility of color filtering of white method for achieving full-color displays using OELDs. Here, we fabricated white organic electroluminescent devices (OELDs) and drove moving images with a 384${/times}$160 pixel.

Aluminum oxide thin films were grown on a poly ethylene naphthalate (PEN) substrate at the temperature of 100$^{\circ}C$ using atomic layer deposition method. The film showed very flat morphology and good adhesion to the substrate. The visible spectrum showed higher transmittance in the range from 400 nm to 800 nm than that of PEN. The water vapor transmission value measured with MOCON for 230nm oxide-deposited PEN was 0.62g/$m^2$/day @ 38$^{\circ}C$, while that of PEN substrate was 1.4g/$m^2$/day @ 38$^{\circ}C$.

The chemical vapor condensation process of Parylene-N thin films was investigated and applied to the passivation of the organic light emitting diodes (OLEDs). The effects of process variables on the deposition rate were studied, and it was found that the deposition rate of Parylene increases with increasing precursor sublimation temperature but decreases with increasing substrate temperature. The Parylene film was used as a passivation layer for OLEDs, and as a result, the lifetime of the passivated OLEDs was increased by a factor of about 2.3 compared with that of non-passivated OLEDs.

In order to reach the high quality of organic thin films such as high mobility for device applications, it is strongly desirable to study the growth properties of pentacene film as a function of evaporation condition. Here, we report the structure and morphology of thermal evaporated pentacene thin film by AFM, SEM, and XRD as a function of the evaporation rate and substrate temperature. These results play a key role in determining the electric performance of organic thin film transistor devices.

A new method for the preparation of copper activated zinc sulfide phosphors by combustion method has been proposed. Copper nitrate was decomposed with an organic fuel to give fine sized particles in presence of alkali metal halides at low temperature than the conventional synthesis. Organic compound also acted as fuel at 500 $^{\circ}C$ with rapid heating. The phosphors thus obtained were then heated at 900 $^{\circ}C$ in an inert atmosphere for 2-5 hrs to get better luminescent properties.

The bilayer organic light-emitting diode using Al (DBM) $_3$ (DBM=Dibenzoylmethane) as an emitting material and poly (N-vinylcarbazole) (PVK) as hole-transport material, emitted bright blue-green light instead of blue light. The blue-green emission is attributed to exciplex formation at the solid interface between Al (DBM) $_3$ and the hole-transport material. The exciplex formation was evidenced by the measurement of the photoluminescence spectra and lifetimes of Al (DBM) $_3$, PVK and an equimolar amount of mixture of Al (DBM) $_3$ and PVK.

We have seen the effects of hole-injection buffer layer in organic light-emitting diodes using copper phthalocyanine(CuPc), poly(vinylcarbazole)(PVK), and Poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate)(PEDOT:PSS) in a device structure of ITO/buffer/TPD/$Alq_3$/Al. Polymer PVK and PEDOT:PSS buffer layer was made using spin casting method and the CuPc layer was made using thermal evaporation. Current-voltage characteristics, luminance-voltage characteristics and efficiency of device were measured at room temperature with a thickness variation of buffer layer. We have obtained an improvement of the external quantum efficiency by a factor of two, four, and two and half when the CuPc, PVK, and PEDOT:PSS buffer layer are used, respectively. The enhancement of the efficiency is attributed to the improved balance of holes and elelctrons due to the use of hole-injection buffer layer. The CuPc and PEDOT:PSS layer functions as a hole-injection supporter and the PVK layer as a hole-blocking one.

A new dry-processing method of organic gate dielectric film in field-effect transistors (FETs) was proposed. The method use vapor deposition polymerization (VDP) that is continuous and low temperature process. It has the advantages of shadow mask patterning and dry processing in flexible low-cost large area applications. Here, 80 nm-thick Al as a gate electrode was evaporated through shadow mask. Gate insulators used two different polyimides. The one material was 4,4'-oxydiphtahlic anhydride (ODPA) and 4,4'-oxydianiline (ODA). Another was 2,2-bis(3,4-dicarboxyphenyl) Hexafluoropropane Dianhydride (6FDA) and 4,4' -oxydianiline (ODA). These were co-deposited by high-vaccum thermal-evapora and cured at 150 $^{\circ}C$ for 1 hour, respectively. Pentacene as a semiconductor and 100 nm-thick Au as a source and drain electrode were evaporated through shadow mask.

Efficient organic white light-emitting diodes are fabricated by doping [bis(2-methyl-8-quinolinolato) (tripheny-siloxy)aluminium (III)] (SAlq), a blue-emitting layer, with a red fluorescent dye of 4-dicyanomethylene-2-methyl-6-{2-(2,3,6,7-tetrahydro-1H,5H-benzo[i,j]quinolizin-8-yl)vinyl}-4H-pyran (DCM2). The incomplete energy transfer from blue-emitting SAlq to red-emitting DCM2 enables to obtain a balanced white light-emission. A device with the structure of ITO/TPD (50 nm)/SAlq:DCM2 (30 nm, 0.5 %)/$Alq_3$ (20 nm)/LiF (0.5 nm)/AI shows emission peaks at 456 nm and 482 nm from SAlq and at 570 nm from DCM2. The white light-emitting device shows an external quantum efficiency of about 2.3 %, a luminous efficiency of about 2.4 lm/W, and the CIE chromaticity coordinates of (0.32, 0.37) at 100 cd/m^2. A maximum luminance of about 23,800 cd/m^2. is obtained at 15 V and the current density of 782 mA/cm^2.

We report the performance of pentacene-based organic thin film transistors (OTFT) with PMMA (polymethyl methacrylate) as the gate insulator which was spin-coated on the ITO (indium tin oxide) glass substrate which was used as the gate contact. The pentacene thin film was deposited on the PMMA film and then Au source/drain contacts were deposited through shadow mask. The pentacene film shows better molecular ordering on PMMA compared with $SiO_2$ of Si wafer. The devices exhibited the field effect mobility of ${\sim}0.004cm^2$/Vs and on/off current ratio of ${\sim}10^3$.

We report very efficient white OLEDs consisting of a blue-emitting 4,4'bis[N-(1-napthyl)-N-phenyl-amino]-biphenyl (${\alpha}$-NPD), a hole-blocking layer of 2,9-dimethyl-4, 7-diphenyl-1, 10-phenanthroline (BCP) doped with red fluorescent dye of 4-dicyanomethylene-2-methyl-6-[2-(2,3,6,7-tetrahydro- 1H, 5H-benzo[i,j]quinolizin-8-yl) vinyl]-4H-pyran) (DCM2), and green-emitting tris(8-hydroxyquinoline) aluminum ($Alq_3$). The device with the structure of ITO/${\alpha}$-NPD (50 nm)/BCP:DCM2 (0.8 %, 4 nm)/$Alq_3$ (50 nm)/LiF (0.5 nm)/Al shows a white emission with the CIE coordinates (0.329, 0.333). The maximum luminance of 20,800 cd/$m^2$ is obtained at 15.4 V. The power efficiency is 2.6lm/W and the external quantum efficiency is 2.1 % at a luminance of 100 cd/$m^2$ at the bias voltage of 6 V.

Oganic light emitting diodes (OLEDs) using PBD(2-(4-biphenylyl)-5-(4-tert-butylpheny)-1,3,4oxadiazole) as a hole blocking layer were fabricated and their device performances were investigated. The devices have a structure of glass substrate ${\setminus}$ indium tin oxide (ITO) ${\setminus}$ TPD(HTL)${\setminus}$PBD,BCP(HBL)${\setminus}$Alq3(EIL)${\setminus}$Mg:Ag(cathode). In this work Bathocuproine(BCP:2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline) and PBD which were previously known as a good ETL material were used as a HBL. By employing HBL, the luminance and quantum efficiency of OLEDs could be improved due to the increase of recombination probability of electrons and holes.

The phosphors of high luminous efficiency for PDP application must have high purity, single phase, and dense surface. In this work, the polymeric reaction was applied to preparation of spherical phosphor by aerosol pyrolysis in order to enhance mechanical and optical characteristics. The red phosphor of (Y,Gd)$BO_3$:Eu was prepared from polymeric precursor, in which citric acid and ethylene glycol were used as ion carriers, i.e monomers. For enhancing the luminescence intensity and mechanical characteristics. optimum synthesizing condition were investigated through concentration of monomers, synthetic temperature. doped activator concentrations, and annealing process. The phosphors synthesized with monomers showed quite different morphology from those without monomers. It was observed that polymeric precursor made an effect on particle formation mechanism and status of particles surface. The resultant spherical phosphors show the comparable luminescent properties to the commercial product (product by Nichia co.). Also, they were observed to have the rigid surface.

Uniform cylinder-shaped precursors for (Y,Gd)$BO_3$:Eu phosphors were prepared by urea hydrolysis reaction. After heating the precursors at lower temperature than general synthetic methods, the phosphor powders were well dispersed and held their original shapes. Their emissions under vacuum-ultraviolet (VUV) excitation appeared with the peaks at 593nm due to magnetic dipole transition from $^5D_0$ to $^7F_1$, 612nm and 627nm due to electric dipole transition from $^5D_0$ to $^7F_2$

Replacing Pb-free glass composition for the dielectric materials is expected in PDP industry. In this study, phosphate glasses, $P_2O_5$- ZnO- SnO (PZS), $P_2O_5$-ZnO-BaO (PZB) were selected for a new transparent dielectric. Thermal properties (Tg, CTE) were measured with differential thermal analyzer and thermal mechanical analyzer. The glass transition of the glasses was ranged at $365{\sim}405^{\circ}C$ for the PZS system and $5.9{\sim}9.5{\times}\;10^{-6}$ of thermal expansion were found. The PZB system showed $445{\sim}470^{\circ}C$ of glass transition. Thus, the glass compositions would be a potential candidate for a transparent dielectric layer in plasma display panel.

For purer images in plasma display panel, a new dielectric compositions containing neodymium oxide were studied. In the present study, Pb-based compositions were used as mother glasses (PbO-$B_2O_3-SiO_2Nd_2O_3$) and thermal, dielectric, and optical properties were measured. As a result the new dielectric with a rare-earth oxide made selectively visible light penetrated and showed especially noticeable absorption properties at 585 nm that is surely related to the erroneous gas from Ne discharge. Thus, this light purple colored glass composition will help PDP to come true to get better imaging process.

Flame spray pyrolysis was applied to improve the photoluminescence characteristics of blue-emitting $Sr_5(PO_4)_3Cl:Eu^{2+}$ phosphor particles with high brightness for the application to LED phosphor. $Sr_5(PO_4)_3Cl:Eu^{2+}$ prepared from conventional spray pyrolysis had poor PL intensity than that of commercial products under long-wavelength ultraviolet(UV). $Sr_5(PO_4)_3Cl:Eu^{2+}$ phosphor particles prepared by flame spray pyrolysis had PL intensity as same as that of commercial products under long-wavelength UV. Hollow morphology and porous structure of the particles prepared by the flame spray pyrolysis disappeared after posttreatment. Even though the $Sr_5(PO_4)_3Cl:Eu^{2+}$ phosphor particles prepared by the flame spray pyrolysis had irregular shape, the particles had dense structure and clear surface property.

$GdPO_4$:Tb phosphor particles with spherical shape and high photoluminescence were prepared by spray pyrolysis. The brightness of prepared $GdPO_4$:Tb under the vacuum ultraviolet(VUV) illumination was comparable with that of the commercial $Zn_2SiO_4$:Mn phosphor particles. The photoluminescence spectra of $GdPO_4$:Tb phosphor particles had maximum peak at 547 nm, and the sharp peaks at 480 nm, 580 nm, and 620 nm. The spherical morphology of prepared $GdPO_4$:Tb particles was completely maintained even after the posttreatment up to 1100 $^{\circ}C$. When the posttreatment temperature was over 1100 $^{\circ}C$, the particles did not have the spherical shape anymore. The average particle size of $GdPO_4$:Tb phosphor particles prepared by using $(NH_4)_2HPO_4$ was changed from 0.5 to 1.9 ${\mu}m$ and its effect on the PL intensity was investigated. It was found that the optimized $GdPO_4$:Tb particles have a good excitation spectrum comparable to that of the commercial $Zn_2SiO_4$:Mn phosphor particles under the VUV illumination from 140 to 220 nm. We concluded that the $GdPO_4$:Tb phosphor particles with spherical shape prepared by spray pyrolysis is a promising candidate for a green-emitting PDP phosphor.

$(Ba,Sr)_2SiO_4:Eu^{2+}$ phosphor particles with high brightness were prepared by spray pyrolysis. The changes in the photoluminescence intensity and morphology of $(Ba,Sr)_2SiO_4:Eu^{2+}$ were investigated by changing the posttreatment temperature and the concentration of dopant. The prepared $(Ba,Sr)_2SiO_4:Eu^{2+}$ particles has a dense structure, but irregular shape after the posttreatment. When they were excited by the ultraviolet light of 410 nm, a broad emission band with a peak at 508 nm was observed. The photoluminescence intensity of the prepared $(Ba,Sr)_2SiO_4:Eu^{2+}$ particles was enhanced by increasing the posttreatment temperature up to 1300 $^{\circ}C$ and further improved by adding several rear-earth codopants. The $(Ba,Sr)_2SiO_4:Eu^{2+}$ particles prepared by spray pyrolysis had a good excitation spectrum in the wavelength longer than 350 nm. Therefore, it was concluded that the $(Ba,Sr)_2SiO_4:Eu^{2+}$ prepared by spray pyrolysis is a good green-emitting phosphor for LED application.

Mn doped hexagonal phase of ZnS has been studied as a yellow-orange phosphor for the application to fluorescent displays operated at low voltages. It was found that luminescence from $Mn^{2+}$ was increased as the Mn concentration was increased up to1.2 mol% of host lattice. This study has been attempted by adding trivalent ions such as $Al^{3+}$ or $Bi^{3+}$ to ZnS:Mn as an agent to do the efficient incorporation of Mn ions into ZnS:Mn lattice, resulting in a significant improvement in the phosphor performance, especially at low voltages.

Photoluminescenc (PL) and low-voltage cathodoluminescence (CL) characteristics of $[xSrTiO_3+(1-x)Li_2TiO_3]:Pr^{3+}$ and $[xSrTiO_3+(1-x)Na_2TiO_3]:Pr^{3+}$ systems were investigated. The red luminescence intensities of these compounds are enhanced remarkably by the incorporation of $Li^+$ or $Na^+$ ion as compared to that of $SrTiO_3:Pr^{3+}$. The enhanced luminescence is speculated to result from both the charge compensation of $Pr^{3+}$ site and oxygen vacancies generated in the lattices by $Li^+$ or $Na^+$ ion.

Transparent conducting ZnO:$Ga_2O_3$ thin films were deposited on glass substrates using rf magnetron sputtering method. The ZnO:$Ga_2O_3$ thin films were highly c-axis oriented normal to the substrates and had smooth surface features. The sheet resistance of the films was 2.8-6.4 ${\Omega}/{\square}$ at the growth temperature ranging from 25 to 30$^{\circ}C$.

The polymer encapsulation of white inorganic $TiO_2$ pigment particles was prepared by a two stage dispersion polymerization technique for applications in electrophoretic displays (EPDs). In order to give functionality for inorganic pigment particles in the EPD, we have investigated the density of the polymer encapsulated $TiO_2$ particles. The average density of the polymer encapsulated $TiO_2$ particles was 2.2 at 25$^{\circ}C$. The average density of the polymer encapsulated $TiO_2$ particles is suitable to 1.7, due to density matching with suspending media. Therefore, we will attempt density compatibility of dispersion polymerization technique for encapsulation of $TiO_2$ particles in suspending media.

In this study, we have investigated a simple process of preparation of white pigment particles by physical coating with functionalized wax for the electrophoretic display. We will discuss, especially, the implementation of bistable pigment providing high mobility by using unique charge control agent and also optical properties of wax coated $TiO_2$ particles.

A novel ceramic synthesis technique, combustion synthesis, is explored to produce an orange-emitting $SnO_2:Eu^{3+}$ phosphors. This technique involves a reaction of metal salts with a citric acid as an organic fuel. The variation of the ratio of citric acid to metal introduces change in reaction temperature and atmosphere of the combustion reaction, which in turn influences crystallinity and luminescence properties of the final products significantly. And the heat treatment of the as-synthesized product improved the CL intensity of the products. Especially, the sample treated at above 1100 $^{\circ}C$ shows an orange-emission, which is attributed to the formation of single phase and well-crystallized $SnO_2$:Eu in rutile structure.

The 17" Backlight Unit (BLU) employing twelve EEFLs (External Electrode Fluorescent Lamp) has been developed for LCD-TV The characteristics of the EEFL BLU without dual brightness enhancement film (DBEF) were equivalent to those of CCFL (Cold cathode Fluorescent Lamp) BLU employing eight CCFLs with DBEF. Luminance, power consumption and uniformity were 12,000nits, 32watt and 80%, respectively. The inverter of EEFL Backlight Unit is composed of 2 transformers and driven by the sinusoidal waveform.

$M(WO_4)$:Eu phosphor as a red emitting phosphor for LED was prepared by solid state method. Tungstate phosphors were exited at long wavelength ultra violet region. In special, the emission of Eu-doped $M(WO_4)$:Eu phosphor under the excitation of 410nm appeared at 613nm. $M(WO_4)$:Eu phosphors with M : Group 1 had a higher excitation intensity than those of the phosphors with M: Group 2 at long-wavelength UV.

We report on the properties of ITO thin films prepared by dc and pulse magnetron sputtering at low temperature. The electrical, optical, and surface properties of the films prepared by dc and pulse magnetron sputtering were compared. We discuss the role the pulse power plays in determining ITO thin film properties that are important in flat panel applications.

A large-area (830mm ${\times}$ 1,020mm) inductively coupled plasma source with a six internal straight antennas was developed for large area FPD etch process applications and the effects of magnetic fields employing permanent magnets on the plasma characteristics were investigated. By employing the magnetic fields perpendicular to the six straight antenna currents using permanent magnets, improved plasma characteristics such as increase of the ion density and decrease of both electron temperature and plasma potential could be achieved in addition to the stability of the plasma possibly due to the reduction of the electron loss. However, the application of the magnetic field decreased the plasma uniformity slightly even though the uniformity within 10% could be maintained in the 800mm processing area.

This research describes a image-processing technique for the scratch detecting algorithm for ITO coated glass. We use the modified logical thresholding method for binarization of gray-scale glass image. This method is useful to the algorithm for detecting the scratch of ITO coated glass automatically without need of any prior information of manual fine-tuning of parameters.

Quality of the reflective LCD as a display is strongly influenced by the environment where the display is evaluated. Up to now, several methods for the evaluation of the reflective LCDs have been proposed. We have developed a new method in which the optical characteristics of the reflective LCDs from the spot light and the diffuse light can be obtained at the same time. The results obtained in our experiments by using the new method showed a good agreement with those evaluated at office and outdoor environments.

A system for high-resolution analysis of defective elementary cell (R, G or B) on Flat Panel Display (FPD) is described. Based on multiple acquisitions of low-resolution shifted images of the display, our system doesn't require a high-resolution sensor neither tedious alignment of the display, and will remain up to date even facing an important increase of the display dimensions. Our process, highly automated and thus flexible and robust, is expected to perform a full analysis in less than 60s. It is mainly intended for production tests and display classification by manufacturers.

In this study, Ag thin films deposited on LCD-grade glass were etched using inductively coupled fluorine-based plasmas and the effect of various $CF_4$-based gas mixtures on the Ag etching characteristics were studied. When $CF_4$-based gas mixtures were used with $N_2$, due to the very low vapor pressure of etch products, etch products remained on the substrate after the etching. However, when $CF_4$ used with Ar, residue-free Ag etching could be obtained due to the removal of etch product by sputtering by $Ar^+$ ions.

LG Electronics developed a perfect flat color display tube which was named "FLATRON" . This tube provides ergonomic performances with perfectly flat face and innovative manufacturing process. Foil transfer is a new technology for manufacturing screen layer for Flatron. Its main features include several properties of film, releasing agent, adhesive, aluminum layer, holes after bake-out and foil transfer process. It will be used innovative and cost oriented process for FLATRON for in CRT mass production..

In this paper, we introduce an efficient three-dimensional magnetic field mapping system for a Deflection Yoke (DY) in Cathode-Ray Tube (CRT). A three-axis Hall probe mounted in a small cylindrical bar and three stepping motors placed in a nonmagnetic frame are utilized for the mapping. Prior to the mapping starts, the inner contour of DY is measured by a laser sensor to make a look-up table for inner shape of DY. Three-axis magnetic fields are then digitized by a three-dimensional Hall probe. The results of the mapping can be transformed to various output formats such as multipole harmonics of magnetic fields. Field shape in one, two and three-dimensional spaces can also be displayed. In this paper, we present the features of this mapping device and show some analysis results.

This paper presents an efficient method of estimating the correlated color temperature of an input color image and of generating a converted color image that can approximate the new target color temperature. After extracting the potential reference white region for an uncalibrated color image and estimating its correlated color temperature, the color conversion method produces a new color image with a target color temperature. Speed improvement and memory reduction have been achieved by using a simple transfer method without involving the CIE XYZ conversion step.

A novel driving technology of PDP, which enables to decrease the sustain voltage of conventional technology by half without lowering the gas discharging voltage. This technology, realizable without much increased cost of the semiconductor devices, gives a significant improvement in the power efficiency, essential for the design of a drive circuit for PDP. A comparative analysis and experimental results are presented to show the validity of the proposed driving technology.

We have proposed a novel optical design technique of light-guide plates(LGPs) which can able to improve the optical efficiency of transflective LCDs. The basic concepts of our design technique are that we make the groove-pattern of LGP pixels resemble the pixel-array-pattern of transflective LCDs in shape and size and make the surface of the groove scatter (front scattering). In simulated and measured results, we ensure that our design of LGP in backlight unit for transflective LCDs can improve the optical efficiency of LCDs.

A new exposure time scheduling scheme to implement the optimized photopolymer-based VHOE is proposed and using this method, the 8-view VHOE system is experimentally developed. The CGS dependence on the exposure energy is mathematically modeled using the fourth-order polynomial function and using this model optimized exposure-time schedule for recording the given multiple gratings in the photopolymer is calculated. In addition, basing on this suggested exposure-time schedule, 8-view VHOE is finally implemented and its performance is discussed.

In this paper, a new 3D robot vision system using the hierarchical opto-digital algorithm is proposed and implemented. From some experimental results with the 20 frames of the stereo input image pairs, the proposed system is found to be able to effectively extract the area where the target object is located from the stereo input image regardless of the background noises.

We studied characteristics of polyimide (PI) about Liquid Crystal on Silicon (LCOS) microdisplay. In order to compare two kinds of PI and choose one PI, we measured some items. First, we measured thermal imidization of SE-7492, SE-5291 (Nissan) PI using FT-IR. The results of thermal imidization are same 85%for SE-7492 and 86% for SE-5291. The second, we measured voltage-holding ratio (VHR) of LCOS imager using two kinds PI and one liquid crystal (LC) that is a mixture developed by Merck. The third, we measured contrast ratio (C/R) of LCOS imager using function generator from ov to 4V. The results of VHR and C/R are higher LCOS imager using SE-7492 than LCOS imager using SE-5291. And last we measured response time and the result is same two types LCOS Imagers. So, we choose PI of LCOS imager and concluded that LC is much better matched of PI using SE-7492.

In this paper, we propose a 3D image player for LCD monitors as well as CRT monitors. As we consider an afterglow and digital processing of LCD monitors, a stereoscopic images can be shown on CRT monitors as well as LCD monitors using the proposed a3D image player. We have implemented a 3D image player using FPGA (MAX 9320), We show prove that a stereoscopic images are shown on the LCD monitors.

Display performance of mobile LCDs has been improved according to broadening of their application. But there are many demands from market, such as contrast improvement (high color reproducibility), higher efficiency of light usage, thickness reduction, widening its viewing angle and so on. To respond them we have been developing many new types of films. In this paper we introduce new high contrast white polarizers for better color reproducibility, and new film construction for higher light efficiency.

Characteristics of reflective LCDs, which have gained a lot of notice in recent years, rely largely on optical design of circular polarizers and the quarter-wave plates, as a component. Important design includes wavelength dispersion, viewing angle, uniformity of display and matching of refractive index. Our work has contributed to improving performance of reflective LCDs by enhancing the characteristics of polymer film using stretching and optical lamination technologies. To design that offers higher contrast and wider viewing angle, we have discovered that it is necessary to control viewing angle variation of the polarizing axis in order to compensate for the viewing angle of the polarizing film as well as the optical anisotropic properties of liquid crystal. Applying this technology to circular polarizers used for reflective LCDs enables design of wide viewing angle circular polarizers. In order to realize higher contrast for reflective LCDs, it is also necessary to design other optical materials including polarizing films. For design of hybrid optical film, it is particularly necessary to reduce surface reflection and interface reflection. This paper also reports our findings concerning this topic.

We have achieved an improved stability of an analog electro-optic effect in FLC/polymer composite films. The optimization of device depends on both the composition of the FLC/polymer mixture and the energy of UV irradiation. This device exhibits continuous gray scales and the mechanical stability against external forces.

We have obtained high performance and low voltage driving OCB panel by reducing the critical voltage and retardation matching between liquid crystal layer and compensation films. The critical voltage in the panel has been minimized by flattening color filter layer and optimizing a rubbing process. In addition, an appropriate retardation of the film and LC layer has scanned to achieve low driving voltage and high transmission. The proto-type 17" WXGA OCB panel has demonstrated with less than 5V drive and over 80 degree for all viewing direction except for rubbing direction with over 90% of TN light efficiency.

Vertically Aligned (VA) technology is an advanced technology for TFT-LCDs, which is mainly used in larger size displays like monitors for desktop computers and even for TVs. We will review our recent developments of Liquid Crystal (LC) mixtures for VA display modes.

We have developed the novel liquid crystal materials with a difluoromethyleneoxy (CF2O) moiety as a linkage group in order to satisfy the diversified various requirements for AM-LCDs. These novel CF2O LC materials have excellent physical properties that are high dielectric anisotropy, low viscosity and wide nematic temperature ranges. Physical properties measurement results that mixtures containing CF2O LC materials have suitable for characteristics for AM-LCDs. The CF2O LC materials are excellent compound for quick response and low driving voltage application.

We have carried a theoretical study on e-beam addressed liquid crystal projection display in which the liquid crystal is switched by the electric field of the charge, produced by an electron beam, on the surface of the display. We calculated the electric field produced by the surface charge, the liquid crystal director configuration and the profile of the transmitted light. We studied the factors affecting the resolution of the display. We also studied the effect of pretilt angle on the performance of the display. The e-beam addressed liquid crystal projection display potentially has the advantages of high resolution and high brightness.

In this paper, new non-chiral molecules with semi-fluorinated alkyl chains were synthesized varying the structure of central bent core unit. Their mesomorphic properties were investigated by DSC and polarized microscopy. The compound with 1,3-dihydroxy phenylene unit could form an enantiomeric smectic phase, but the remaining compounds with bent-core mesogenic unit were not liquid crystalline. In this presentation, their x-ray measurement and electro-optical property will be also described.

The optically addressed and electrically addressed spatial phase only light modulators without pixelized structures have been developed. A sufficient phase modulation capability and a high diffraction efficiency of these devices are useful for practical applications.

Liquid Crystal Spatial Light Modulators (LC-SLMs) provide many interesting applications in laser optics and opto-electronic systems, in addition to displays. Among them, three topics developed at Thales Research & Technology are reviewed: wavefront correction for laser beam control, microwave processing in radar systems and holography for TN-LCDs viewing angle compensation.

A new concept of forming self-aligned multidomains is used for fabricating wide-viewing liquid crystal displays (LCDs) with periodic surface gratings.An array of the periodic surface gratings is produced on substrates using a photosensitive polymer by the illumination o. the UV light through a patterned photomask. A multidomain structure is naturally formed on the grating surface by the initial director distortions together with continuous variations of an external electric field. The LCD cells with periodic surface gratings are found to show excellent extinction in the off-state and wide-viewing property m the on-state.

We successfully developed new photo-alignment materials which can be treated with linearly polarized UV (LPUV) light in near UV region. The alignment films were also shown to provide with surface anchoring as strong as that on rubbed polyimide when exposed to the LPUV light with warming up the substrate. It can be also able to control pretilt angle by introduction of alkyl side chain.

We propose an optical configuration of a hybrid-aligned nematic liquid crystal cell for reflective displays by which we can achieve wide viewing angle and uniform reflection spectrum.

This paper will review the driving methods and issues of driving circuitry for passive matrix organic electro-luminescent displays(PM-OELDs). And it will shows the proposed one-chip and two-chip solution for driving the PM-OELDs and also the pixel structure and driving methods of active matrix (AM-OELDs). We will discuss the proper applications of OELDs with its power consumption by comparison with that of LCD.

In this paper, we study the performances of optical system design using the 1 panel LCD without color filter for projection color television. We analyze the optical efficiency compare this system with 1 panel LCD system using the color filter, and work out a constraint condition of 1 panel LCD without color filter for optical design. We design a high brightness 1 panel optical system using a complex reflection mirror and suggest a method of the optical system design.

Barrier ribs in the color plasma display panel(PDP) function to maintain the discharge space between to glass plates as well as to prevent optical crosstalk. Patterning of barrier ribs is one of unique processes for making PDP. In this work photosensitive barrier rib pastes were prepared by incorporating binder polymer, solvent, functional monomers photoinitiator, mid barrier rib powder. Study on the function of materials for the barrier rib paste were undertaken. After optimization of paste formulation, both photolithographic and transparent soft molding method resulted in fine pattern of barrier ribs with high aspect ratio.

We present a novel fabrication method for a V-grooved mold of the light guide plat of TFT-LCD with MEMS technology. This method is performed by the inclined UV lithography and Ni electroplating unlike the previous mechanical processing technique. V-grooves with different dimension can be made simultaneously with single photomask.

This paper presents the color displays using more than three primary colors, for the reproduction of wider color gamut, and high-fidelity color reproduction. First, Natural Vision system, which is currently under development for the natural color reproduction in visual telecommunication applications, is introduced, The natural vision is based on spectrum instead of trichromatic color space, and enables high-fidelity color reproduction using multispectral and multiprimary technologies. Then, sixprimary color projection displays using LCD and DLP, and a four-primary color flat panel display are shown. It is experimentally demonstrated that the color gamut becomes much larger than conventional RGB-based display. In addition, it is proved that the spectral color reproduction using multiprimary display suppresses the influence of observer metamerism, and as a result, the color matching between the display and the real object is well improved.

The authors introduce 3D display systems developed in our laboratories for recent ten years. Those are mainly realized by several technologies in holography: electro-holography. holographic stereogram, holographic optical elements (HOE) and hologram screen. We are currently focusing the development of 3D projection screen without glasses. Powerful directionality of the light beam is required for 3D projection screen unlike 2D type. We succeeded in achieving the superior diffractive efficiency of hologram screen that is based on the advanced volume holography. This technology is extensively useful to retrieve the Bragg condition of volume hologram in the three-dimensional space. Owing to this technology we could establish the principle of multi-view projection screen and have confirmed the case of 4 viewing points.

We developed a Retinal Projection Display for a low vision aid. This device can be applied to a low vision whose visual sense is weak. In the device, a digital image was formed with spatial light modulator(SLM) and projected onto a retina with the Maxwellian View. The image on this display can be seen clearly without our ocular accommodation and a low vision can see it without correction of a refraction error.

The deposition of $SrGa_2S_4$ thin film phosphors doped with Ce or Eu aiming at application for FEDs has been carried out by a multi-source deposition technique. A $SrGa_2S_4$ phase was formed by annealing process and $SrGa_2S_4$ thin films which were deposited using a $Ga_2S_3/Sr$ flux ratio larger than 50 and annealed in $H_2$S showed luminance and luminous efficiency of about 1700 cd/$m^2$ and 2.95 lm/W, respectively, with (0.13, 0.10) chromaticity in the activation with Ce, and about 4000 cd/$m^2$ and 7.05 lm/W, respectively, with (0.36, 0.60) under excitation with 3 kV and 60A/$cm^2$. The results obtained this experiment demonstrate the potential of $SrGa_2S_4$ thin film phosphors for FED screens.

We successfully developed a-Si TFT controlled active matrix cathode (AMC) with gated Mo emitters. Also, we could remove emitter failures of the AMC through a novel surface treatment of Mo-tips, which indicates reduction of $MoO_3$ or chemical wet etching of $MoO_3$ by surface treatment. Transient behaviors of the AMC are strongly dependent on not only DC characteristics of device but also the device structure. Brightness and gray scale were well realized by low-voltage scan and data signals addressed to a-Si TFTs.

In this study, we have investigated the substitutional effects of In ions with divalent ones in the $Srln_2O_4:Pr^{3+}$ phosphors and the relative change of the red and blue emissions. The substitutional Zn ions greatly intensified the blue emission band at 492 nm, but the red emission band at 608 nm was relatively less changed. On the other hand, Cd ions have no effect on the relative intensities. We explained the phenomena in connection with the distance of Pr-D, i.e., covalency experienced by a $Pr^{3+}$ion.

Ga-based semiconductor nanowires (GaN, GaP) were synthesized by the reaction of Ga metal and GaN/GaP powder with a $NH_3/Ar$ gas using thermal chemical vapor deposition. The field emission and emission stability under oxygen and argon environments were investigated. Field emission energy distributions of electrons from these nanowires revealed that field emission mechanism of the semiconductor nanowires were different from carbon nanotubes.

The electrical properties of Porous polycrystalline silicon Nano-Structure (PNS) as a cold cathode were investigated as a function of anodizing condition, the thickness of Au film as a top electrode and the substrate temperature. Non-doped 2${\mu}m$-polycrystalline silicon was electrochemically anodized in HF: ethanol (=1:1) mixture as a function of the anodizing condition including a current density and anodizing time. After anodizing, the PNS was thermally oxidized for 1 hr at 900 $^{\circ}C$. Then, 20nm, 30nm, 45nm thickness of Au films as a top electrode were deposited by E-beam evaporator. Among the PNSs fabricated under the various kinds of anodizing conditions, the PNS anodized at a current density of 10mA/$cm^2$ for 20 sec has the lowest turn-on voltage and the highest emission current than those of others. Also, the electron emission properties were investigated as functions of measuring temperature and the different thickness of Au film as a top-electrode.

For the I-V modeling of sharp tip arrays and nanostructured planar emitters, we propose a new and much practical I-V relation including tip height and radius by considering a statistical distribution of tip radius. Frequently observed nonlinearity of Fowler-Nordheim plot for sharp tip and tip arrays was successfully simulated and then, an application example was provided to extract relevant emission-governing parameters of sharp tip.

A 50% reduction of convergence errors of CRT's is achieved by a technique referred to as 'Magnetically Improved Color Alignment' or MICA for short. The MICA technology comprises a ring of synthetic material (polymer) filled with ferrite particles. MICA is meant for repairing CRT's, which are out of convergence specification. The repairing occurs by writing a magnetic correction profile in the ring.

Generally, the Black Matrix of CRT is formed by the application of photoresist and black material separately. We have developed the simple process for black matrix of CRT. We used the black photoresist, It made it possible that the formation of Black Matrix by application of the light exposure and development only once.

Vacuum surroundings in Cathode Ray Tubes (CRT) are very important factor for CRT lifetime, especially cathode & getter's. A getter is a very good vacuum pump; unfortunately, it cannot absorb an inert gas and hydrocarbons. There are only argon and helium in CRT after $1^{st}$ emission test because other active gases are absorbed by getter and methane is decomposed during CRT working. It is also very important to know exactly where and when methane is decomposed during the CRT manufacturing process, because methane is known to be harmful to cathode when its amount is high, and getter can't absorb the methane.

Recently CRT is getting large-sized, Flatness and High Fine Pitched in the meantime the raw material for shadow mask is in rapid progress of thinness, Low Thermal Expansion and high strength.Until now we have used AK(Aluminum Killed) & Invar(Fe-Ni alloy) materials for main raw material of shadow mask component. However recently Nb and Co addition and Nb+Co addition, which has advantage of Low Thermal Expansion and High Strength. has been developed as well as applying in mass production as CRT's trend has become more flat and fine pitch. Among of them, Co addition has been mass production as forming type (Flat CRT) with the beneficial effect of low thermal expansion & high strength for the first time. Since then Nb+Co addition has been used in mass production by the request of much higher strength of shadow mask component. In case of Nb addition, It's thermal expansion coefficient is a little lower than normal Invar and a little higher than Co addition, meanwhile Its Mechanical property is almost similar to Co Addition. The used samples of this experiment are 36%Ni + Fe, 32%Ni + 5%Co + Fe, 32%Ni + 5%Co + 0.3%Nb + Fe, 32%Ni + 0.3%Nb + Fe with heat treatment temperature of 600$^{\circ}C$, 650$^{\circ}C$, 700$^{\circ}C$, 750$^{\circ}C$, 800$^{\circ}C$, 850$^{\circ}C$, 900$^{\circ}C$ respectively under the condition of 15min holding time. After heat treatment, we have observed the change of mechanical property with addition of small elements through mechanical property investigation and metal structure observation as well as transition of thermal expansion coefficient by measuring of thermal expansion coefficient at 850$^{\circ}C$. In conclusion, 5%Co addition indicates that its thermal expansion coefficient is very similar under the condition of at 850$^{\circ}C$ for 15min 's heat treatment. From the experimental result it is suggested that Co addition is mostly suitable for Doming property and Nb addition is mostly suitable for Drop property.

The evolution of color CRT electron gun design over the past 40 years is addressed. Many milestones of CRT E-gun design are cited. For the future survival of color CRT the multi-beam group color E-gun and the recently announced multi-beam type index gun are suggested as the answer to the challenge of the next generation's requirements of low power and high performance color CRT

The effects of different optical characteristics between desktop CRT and TFT-LCD were compared in terms of visual performance during a 4-hr visual text and icon search tasks. The result showed that CRT is more suitable for presenting graphic information whereas TFT-LCD is suitable for presenting text information at the state of the art display technology.

In this study, first, we show that the furnace process which requires maintaining high temperature is effected grievously by the temperature of surrounding air. Second, an alternative which maintains the relatively constant temperature dispersion surrounding the furnace and at the same time has economical advantages will be proposed.

We report using thin steel strip (0,1mm) for manufacturing Inner Magnetic Shield of CRT. Here we report that the reducing of steel strip thickness from 0,15mm to 0,1mm is possible as for one-piece IMS and for two-piece IMS without any reflection on quality of CRT. Also we report about advantages, which the producer of CRT could reach using steel with lowed carbon content up to 0,0005% by mass.

Present status of diagnostics and simulations on microplasmas for understandings of the discharge and VUV emission characteristics in a unit cell of plasma display panel is overviewed and their future perspective will be argued towards potential improvement of the characteristics.

Top emission organic EL devices were fabricated by using metal-doped cathode interface layer to achieve low drive voltages. Also, facing-targets-type sputtering was used to sputter indium-tin oxide layer on top of organic active layer. The devices fabricated in this study showed reasonably high external quantum efficiency of about 1 % which is comparable to that of bottom-emission-type devices.

We prepared the blend alignment layers made from coumarin based photopolymer and polyimides for liquid crystal(LC) alignment using linearly polarized ultraviolet(UV) exposure. The alignment properties of LC were found to depend on the type of polyimide in the blend alignment layers. The degree of photereaction of polyimide was important factor for LC alignment direction on the blend alignment layers.

To have cost down and get improved image quality and performance of plasma display panel, several factors have been developed including development of low price material and improvement in production for PDP front plate. In this work, viscosity and surface characteristics of transparent dielectric were investigated to find the optimum and low price materials fabrication condition of transparent dielectric paste. It was found that uniformity and transmissivity of green and fired dielectrics had some relationship with the kinds and content of binder, and solvent as well.

In this study, a new processing route of barrier ribs for the plasma display panels was attempted. A slurry containing ceramic powders for the barrier ribs, binder, hardener, and other additives, was molded into a PDMS mold by capillary infiltration process. The molded slurry was cured prior to mold removal. It was demonstrated that the process can fabricate successfully the cell type barrier ribs of PDP.