• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.4
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• pp.450-455
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• 2010

The performance modeling of a $25{\mu}m$ pitch VGA ${\mu}$-bolometer with the self-aligned thermal resistor structure is carried out. The self-aligned thermal resistor can be utilized for the maximizing the thermal resistance and the fill factor of a bolometer, so the performance improvement can be expected. From the results of the performance modeling of the micro-bolometer with self-align thermal resistor for a $25{\mu}m$ pitch $640{\times}480$ microbolometer designed with $0.6{\mu}m$ minimum feature size, the drastic improvements of NETD from 38.7 mK to 19.1 mK, responsivity of 1.9 times are expected with a self aligned thermal resistor structure. The main reason for the performance improvements with a self-aligned thermal resistor structure comes from the increasement of the thermal resistance.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.4
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• pp.367-372
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• 2006

A carbon nanotube field emission display(CNT FED) panel with a 2 inch diagonal size was fabricated using a screen printing of a prepared photo-sensitive CNT paste and vacuum in-line sealing technology. After a surface treatment of the patterned CNT, only the carbon nanotube tips are uniformly exposed on the surface. The diameter of the exposed CNTs are usually about 20 nm. Using the photo-sensitive CNT paste, we have developed a triode type CNT FEA with a self-aligned gate-emitter structure. The turn on voltage was around 100 V which corresponds to according the turn on field of about $40V/{\mu}m$. By the creation of a self-aligned gate-emitter structure, it is expected that the screen printed photo-sensitive CNT paste is promising as a good candidate for the large size field emission display.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.5
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• pp.54-59
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• 1995

We have proposed a novel self-aligned offset gated polysilicon TFTs device without an offset mask in order to reduce a leakage current and suppress a kink effect. The photolithographic process steps of the new TFTs device are identical to those of conventional non-offset structure TFTs and an additional mask to fabricate an offset structure is not required in our device due to the self-aligned process. The new device has demonstrated a lower leakage current and a better ON/OFF current ratio compared with the conventional non-offset device. The new TFT device also exhibits a considerable reduction of the kink effect because a very thin film TFT devices may be easily fabricated due to the elimination of contact over-etch problem.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.7
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• pp.88-93
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• 1998

For the self-aligned AlGaAs/GaAs HBTs, the surface states at the interface between the extrinsic base surface and the passivation nitride is a major cause of degradation of dc characteristics. In this paper the degradation mechanisms of self-aligned AlGaAs/GaAs HBT were analyzed, and GaAs HBTs, which employed an InGaP ledge emitter structure formed by the nonself-aligned process to cover the surface of the extrinsic base and reduce the surface states, produced high reliability. Accoridng to the acceleration lifetime test, the nonself-aligned InGaP/GaAs HBTs produced very reliable dc characteristics comparing with the self-aligned AlGaAs/GaAs HBTs. The activation energy was 1.97eV and MTTF $4.8{\times}10^{8}$ hrs at $140^{\circ}C$ which satisfied the MIL standard.

• Carbon letters
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• v.12 no.4
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• pp.185-193
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• 2011

Carbon nanotubes (CNTs) have developed into one of the most competitively researched nano-materials of this decade because of their structural uniqueness and excellent physical properties such as nanoscale one dimensionality, high aspect ratio, high mechanical strength, thermal conductivity and excellent electrical conductivity. Mass production and structure control of CNTs are key factors for a feasible CNT industry. Water and ethanol vapor enhance the catalytic activity for massive growth of vertically aligned CNTs. A shower system for gas flow improves the growth of vertically aligned single walled CNTs (SWCNTs) by controlling the gas flow direction. Delivery of gases from the top of the nanotubes enables direct and precise supply of carbon source and water vapor to the catalysts. High quality vertically aligned SWCNTs synthesized using plasma enhance the chemical vapor deposition technique on substrate with suitable metal catalyst particles. This review provides an introduction to the concept of the growth of vertically aligned SWCNTs and covers advanced topics on the controlled synthesis of vertically aligned SWCNTs.

• Bulletin of the Korean Chemical Society
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• v.27 no.3
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• pp.386-388
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• 2006

Membrane proteins in highly oriented lipid bilayer samples are useful for membrane protein structure determination. We used in the past planar lipid bilayers which were aligned and supported on the glass slide. These samples were mechanically aligned in a magnetic field. However, these stacks of glass slides with planar lipid bilayers are not well suited for use with a commercial solid-state NMR probe with a round coil. Therefore, a homebuilt solid-state NMR probe was built and used with a stack of thin glass plates wherein the RF coil was wrapped directly around the flat square sample. Recently, we began to use magnetically aligned bicelles that are suitable for the structure determination of membrane proteins by solid-state NMR spectroscopy without any effort to build a flat square coil probe. These bicelle samples are well suited for use with a commercial solidstate NMR probe with a round coil, are very easy to prepare and are very stable, so that they can be kept for more than a year. In this paper, we present the solid-state NMR spectra of optimized and magnetically oriented bicelle samples of membrane proteins.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.212-212
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• 2000

Since the first obserbvation of carbon nanotubes, extensive researches have been done for the synthesis using arc discharge, laser vaporization, and plasma-enhanced chemical vapor deposition. Carbon nanotubes have unique physical and chemical properties and can allow nanoscale devices. Vertically aligned carbon nanotubes with high quality on a large area is particularly important to enable both fundamental studies and applications, such as flat panel displays and vacuum microelectronics. we have grown vertically aligned carbon nanotubes on a large area of Si substrates by thermal chemical vapor deposition using C2H2 gas at 750-950$^{\circ}C$. we deposited catalytic metal on Si susbstrate using thermal evaporation. The nanotubes reveal highly purified surface. The carbon nanotubes have multi-wall structure with a hollow inside and it reveals bamboo structure agreed with base growth model. Figure 1 shows SEM micrograph showing vertically aligned carbon nanotubes whih were grown at 950$^{\circ}C$ on a large area (20mm${\times}$30mm) of Si substrates. Figure 2 shows TEM analysis was performed on the carbon nanotubes grown at 950$^{\circ}C$ for 10 min. The carbon nanotubes are multi-wall structure with bamboo shape and the lack of fringes inside the nanotube indicates that the core of the structure is hollow. In our experiment, carbon nanotubes grown by the thermal CVD indicate base growth model.

• Korean Management Science Review
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• v.28 no.3
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• pp.47-60
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• 2011

While the literature is replete with arguments that corporate strategy, structure, and culture independently matter in explaining the growth and survival of firms, little theoretical and empirical attention has been devoted to understanding how the three organizational factors develop over time in interaction. Through in-depth case study, we examine the POSCO's historical development with respect to the strategy-structure-culture interface. Furthermore, by looking at the POSCO's longitudinal financial data we gain insight into whether the aligned evolution of strategy, structure, and culture is associated with performance.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.37 no.3
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• pp.1-5
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• 2000

A waveguide of coupled optical modulator was fabricated on LiNbO$_3$ based on proton exchange with self-aligned thin film electrode method. The electrode pattern was designed using a self-aligned method. After proton exchange process, the waveguide was prepared by annealing process. The initial crossover state of the fabricated 2$\times$2 coupled optical modulator was observed with controlling the annealing process variables and the structure of self-aligned thin film electrodes. It was shown form the present work that the measured crosstalk is -29.5[dB] and 8.0[V] of detected modulating voltage.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.440-441
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• 2006

We have studied the narrow viewing angle liquie crystal displays (LCDs) using a hybrid aligned nematic liquid crystal (LC) cell driven by a fringe field. The device using a LC with positive dielectric anisotropy has a relatively low transmittance. This paper describes how to improve light efficiency by optimizing electrode structure. The results show that the device exhibits a high transmittance of 90%, low driving voltage and narrow viewing angle less than $20^{\circ}$ along horizontal direction which is highly effective for private display application.