• Journal of the Optical Society of Korea
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• v.13 no.1
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• pp.65-74
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• 2009

Device quality indium tin oxide (ITO) films are deposited on glass substrates and ultra-thin diamond-like carbon films are deposited as a buffer layer on ITO by a pulsed Nd:YAG laser at 355 nm and 532 nm wavelength. ITO films deposited at room temperature are largely amorphous although their optical transmittances in the visible range are > 90%. The resistivity of their amorphous ITO films is too high to enable an efficient organic light-emitting device (OLED), in contrast to that deposited by a KrF laser. Substrate heating at $200^{\circ}C$ with laser wavelength of 355 nm, the ITO film resistivity decreases by almost an order of magnitude to $2{\times}10^{-4}\;{\Omega}\;cm$ while its optical transmittance is maintained at > 90%. The thermally induced crystallization of ITO has a preferred <111> directional orientation texture which largely accounts for the lowering of film resistivity. The background gas and deposition distance, that between the ITO target and the glass substrate, influence the thin-film microstructures. The optical and electrical properties are compared to published results using other nanosecond lasers and other fluence, as well as the use of ultra fast lasers. Molecularly doped, single-layer OLEDs of ITO/(PVK+TPD+$Alq_3$)/Al which are fabricated using pulsed-laser deposited ITO samples are compared to those fabricated using the commercial ITO. Effects such as surface texture and roughness of ITO and the insertion of DLC as a buffer layer into ITO/DLC/(PVK+TPD+$Alq_3$)/Al devices are investigated. The effects of DLC-on-ITO on OLED improvement such as better turn-on voltage and brightness are explained by a possible reduction of energy barrier to the hole injection from ITO into the light-emitting layer.

• Informatization Policy
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• v.17 no.3
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• pp.74-97
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• 2010

This paper investigates factors that have facilitated the rapid diffusion of broadband in South Korea. It finds that the quick spread of broadband access in South Korea is the result of combining the government's strategic ICT policy considering cultural traits, businesses'competitive efforts, and the timely explosion of domestic demand for IT service. This paper also discusses the impact of broadband diffusion on the digital divide. It finds that although there are still regional and age gaps in broadband access, the Korean government and businesses are working to alleviate these problems through various ways from systemic to physical ones. While the deployment of broadband cannot eliminate every issue of the digital divide, broadband access minimizes the digital divide by lowering the barrier to inequitable access to information. This paper concludes with a number of recommendations that address selected policy issues related to the spread of broadband Internet for its successful implementation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.533-533
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• 2007

The stress effect of SiGe p-type metal oxide semiconductors field effect transistors(MOSFETs) has been investigated to compare device properties using Si bulk and partially depleted silicon on insulator(PD SOI). The electrical properties in SiGe PD SOI presented enhancements in subthreshold slope and drain induced barrier lowering in comparison to SiGe bulk. The reliability of gate oxides on bulk Si and PD SOI has been evaluated using constant voltage stressing to investigate their breakdown (~ 8.5 V) characteristics. Gate leakage was monitored as a function of voltage stressing time to understand the breakdown phenomena for both structures. Stress induced leakage currents are obtained from I-V measurements at specified stress intervals. The 1/f noise was observed to follow the typical $1/f^{\gamma}$ (${\gamma}\;=\;1$) in SiGe bulk devices, but the abnormal behavior ${\gamma}\;=\;2$ in SiGe PD SOI. The difference of noise frequency exponent is mainly attributed to traps at silicon oxide interfaces. We will discuss stress induced instability in conjunction with the 1/f noise characteristics in detail.

• Korean Journal of Materials Research
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• v.16 no.10
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• pp.629-632
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• 2006

Electrical characteristics of Pt/Ti/Pt/Au and Pd/Zn/Pd/Au contacts to p-type InGaAs grown on an InP substrate have been characterized as a function of the doping concentration and the annealing temperature. The Pt/Ti/Pt/Au contacts produced the specific contact resistance as low as $2.3{\times}10^{-6}{\Omega}{\cdot}cm^2$, when heat-treated at an annealing temperature of $400^{\circ}C$. Comparison of the Pt/Ti/Pt/Au and Ti/Pt/Au contacts showed that the first Pt layer plays an important role in reducing the contact resistivity probably by lowering energy barrier at the metal-semiconductor interface. For the Pd/Zn/Pd/Au contacts, the contact resistivity remained virtually unchanged with increasing annealing temperature. The specific contact resistivity as low as $4.7{\times}10^{-6}{\Omega}{\cdot}cm^2$ was obtained. The results indicate that the Pt/Ti/Pt/Au and Pd/Zn/Pd/Au schemes could be potentially important for the fabrication of InP-based optoelectronic devices, such as photodetector and optical modulator.

• Journal of Convergence for Information Technology
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• v.11 no.7
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• pp.104-110
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• 2021

A novel selective oxidation process has been developed for low source/drain (S/D) series resistance of the fin channel metal oxide semiconductor field effect transistor (MOSFET). Using this technique, the selective oxidation fin-channel MOSFET (SoxFET) has the gate-all-around structure and gradually enhanced S/D extension regions. The SoxFET demonstrated over 70% reduction in S/D series resistance compared to the control device. Moreover, it was found that the SoxFET behaved better in performance, not only a higher drive current but also higher transconductances with suppressing subthreshold swing and drain induced barrier lowering (DIBL) characteristics, than the control device. The saturation current, threshold voltage, peak linear transconductance, peak saturation transconductance, subthreshold swing, and DIBL for the fabricated SoxFET are 305 ㎂/㎛, 0.33 V, 13.5 𝜇S, 76.4 𝜇S, 78 mV/dec, and 62 mV/V, respectively.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.30 no.6
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• pp.967-973
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• 2020

As the implementation of export controls is spreading, the importance of classifying strategic items is increasing, but Korean export companies that are new to export controls are not able to understand the concept of strategic items, and it is difficult to classifying strategic items due to various criteria for controlling strategic items. In this paper, we propose a method that can easily approach the process of classification by lowering the barrier to entry for users who are new to export controls or users who are using classification of strategic items. If the user can confirm the decision result by providing a manual or a catalog for the procedure of classifying strategic items, it will be more convenient and easy to approach the method and procedure for classfying strategic items. In order to achieve the purpose of this study, it utilizes deep learning, which are being studied in image recognition and classification, and OCR(optical character reader) technology. And through the research and development of the support tool, we provide information that is helpful for the classification of strategic items to our companies.

• The Korean Journal of Physiology and Pharmacology
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• v.28 no.3
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• pp.275-284
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• 2024

Worldwide, cardiovascular disease is the main cause of death, which accordingly increased by hyperlipidemia. Hyperlipidemia therapy can include lifestyle changes and medications to control cholesterol levels. Statins are the medications of the first choice for dealing with lipid abnormalities. Rosuvastatin founds to control high lipid levels by hindering liver production of cholesterol and to achieve the targeted levels of low-density lipoprotein cholesterol, another lipid lowering agents named ezetimibe may be used as an added therapy. Both rosuvastatin and ezetimibe have low bioavailability which will stand as barrier to decrease cholesterol levels, because of such depictions, formulations of this combined therapy in nanotechnology will be of a great assistance. Our study demonstrated preparations of nanoparticles of this combined therapy, showing their physical characterizations, and examined their behavior in laboratory conditions and vivo habitation. The mean particle size was uniform, polydispersity index and zeta potential of formulations were found to be in the ranges of (0.181-0.72) and (-13.4 to -6.24), respectively. Acceptable limits of entrapment efficiency were affirmed with appearance of spherical and uniform nanoparticles. In vitro testing showed a sustained release of drug exceeded 90% over 24 h. In vivo study revealed an enhanced dissolution and bioavailability from loaded nanoparticles, which was evidenced by calculated pharmacokinetic parameters using triton for hyperlipidemia induction. Stability studies were performed and assured that the formulations are kept the same up to one month. Therefore, nano formulations is a suitable transporter for combined therapy of rosuvastatin and ezetimibe with improvement in their dissolution and bioavailability.

• Advances in nano research
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• v.17 no.2
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• pp.137-147
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• 2024

Graphene nanoribbons (GNRs) are considered a promising alternative to graphene for future nanoelectronic applications. However, GNRs-based device modeling is still at an early stage. This research models the electronic properties of n-doped rough-edged 13-armchair graphene nanoribbons (13-AGNRs) and quantum transport properties of n-doped rough-edged 13-armchair graphene nanoribbon field-effect transistors (13-AGNRFETs) at different doping concentrations. Step-up and edge doping are used to incorporate doping within the nanostructure. The numerical real-space nearest-neighbour tight-binding (NNTB) method constructs the Hamiltonian operator matrix, which computes electronic properties, including the sub-band structure and bandgap. Quantum transport properties are subsequently computed using the self-consistent solution of the two-dimensional Poisson and Schrödinger equations within the non-equilibrium Green's function method. The finite difference method solves the Poisson equation, while the successive over-relaxation method speeds up the convergence process. Performance metrics of the device are then computed. The results show that highly doped, rough-edged 13-AGNRs exhibit a lower bandgap. Moreover, n-doped rough-edged 13-AGNRFETs with a channel of higher doping concentration have better gate control and are less affected by leakage current because they demonstrate a higher current ratio and lower off-current. Furthermore, highly n-doped rough-edged 13-AGNRFETs have better channel control and are less affected by the short channel effect due to the lower value of subthreshold swing and drain-induced barrier lowering. The inclusion of dopants enhances the on-current by introducing more charge carriers in the highly n-doped, rough-edged channel. This research highlights the importance of optimizing doping concentrations for enhancing GNRFET-based device performance, making them viable for applications in nanoelectronics.

• Journal of the Microelectronics and Packaging Society
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• v.23 no.1
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• pp.17-22
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• 2016

Flexible organic light-emitting diode (OLED) devices consist of multi-stacked thin films or layers comprising organic and inorganic materials. Due to thermal coefficient mismatch of the multi-layer films, warpage of the flexible OLED is generated during high temperature process of each layer. This warpage will create the critical issues for next production process, consequently lowering the production yield and reliability of the flexible OLED. In this study, we investigate the warpage behavior of the flexible OLED for each bonding process step of the multi-layer films using the experimental and numerical analysis. It is found that the polarizer film and barrier film show significant impact on warpage of flexible OLED, while the impact of the OCA film on warpage is negligible. The material that has the most dominant impact on the warpage is a plastic cover. In order to minimize the warpage of the flexible OLED, we estimate the optimal material properties of the plastic cover using design of experiment. It is found that the warpage of the flexible OLED is reduced to less than 1 mm using a cover plastic of optimized properties which are the elastic modulus of 4.2 GPa and thermal expansion coefficient of $20ppm/^{\circ}C$.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.38 no.2
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• pp.95-102
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• 2001

Nano-scale gate length MOSFET devices require extremely shallow source/drain eftension region with junction depth of 20∼30nm. In this work, 20nm $n^{+}$-p junctions that are realized by using this $As_{2}^{+}$ low energy ($\leq$10keV) implantation show the lower sheet resistance of the $1.0k\Omega$/$\square$ after rapid thermal annealing process. The $As_{2}^{+}$ implantation and RTA process make it possible to fabricate the nano-scale NMOSFET of gate length of 70nm. $As_{2}^{+}$ 5 keV NMOSFET shows a small threshold voltage roll-off of 60mV and a DIBL effect of 87.2mV at 100nm gate length devices. The electrical characteristics of the fabricated devices with the heavily doped and abrupt $n^{+}$-p junctions ($N_{D}$〉$10^{20}$$cm^{-3}$, $X_{j}$$\leq$20nm) suggest the feasibility of the nano-scale NMOSFET device fabrication using the $As_{2}^{+}$ low energy ion implantation.