• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.5
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• pp.339-343
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• 1999

This paper reports the characteristics of poly-Si TFT unitary CMOS circuits fabricated with various techniques, in order to investigate the optimum process conditions. The active films were deposited by PECVD and LPCVD using $SiH_4\; and\; Si_2H_6$ as source gas, and annealed by SPC and ELA methods. The impurity doping of the oource and drain electrodes was performed by ion implantation and ion shower. In order to investigate the AC characteristics of the poly-Si TFTs processed with various methods, we have examined the current driving characteristics of the polt-Si TFT and the frequency characteristics of 23-stage CMOS ring oscillators. Ithas been observed that the circuits fabricated using $Si_2H_6$ with low-temperature process of ELA exhibit high switching speed and current driving performances, thus suitable for real application of large area electronics.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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• pp.116-119
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• 1997

In this paper A double-layer organic electroluminescent(EL) device was fabricated using a TPD(N,N'-dipheny] -N,N'-bis(3-methylphenyl)-[1,1'-biphenyl]-4.4'-diamine: aromatic diamine), as a hole-transport material and tris (8-hydroxy quinolinate) aluminum(Alq$_3$) as a an emiting material and its performance characteristics were investigated. structure of devices is ITO/TPD/Alq$_3$/Al. we have fabricated hole transport layer of two types. Doping material of Hole Transport material is Poly(methyl methacrylate)(PMMA) and PEI(Poly-Ether-Imide). Carrier injection from the electrodes to the doped PMMA and PEI layer through the dopants and concomitant electroluminescence from Alq$_3$were observed. Green emission with luminance of 40cd/m$^2$was achieved at a drive voltage of 30V

• Electrical & Electronic Materials
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• v.7 no.3
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• pp.206-212
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• 1994

In this paper, We discuss the $POCI_3$ doping process according to the variation of deposition temperature, gas flow rate and doping time. The factors acted with $POCI_3$ doping are gas flow rate deposition temperature and time etc. Among them the temperature is the most important factor. For the $POCI_3$ flow rate, it should not exceed the resistivity saturation point developed on poly surface by annealing treatment. Therefore, this study suggests the optimum conditions of Poly-silicon treatments with the $POCI_3$ flow rate.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.690-692
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• 2003

The single phase switched reluctance motor has been studied and developed actively in the various applications with several kinds and forms because of the developments of the design technique by using the computer and of the driving technique power electronic technology, which has the merits of a simple and robust structure, and first of all reducing the number of the switching devices in comparison with poly phase switched reluctance motor. And also, the studies are making progess to substitute the switched reluctance motor for single phase induction motor. In the previous studies, the single phase switched reluctance motor for the drive of blower is designed with the design theory of the conventional rotating electric machine and poly phase switched reluctance motor. In this paper, we intend to select the optimal pole arc and pole pitch ratio by the FEM analysis, because the pole arc and pole pitch are very important factor to determine the characteristics of switched reluctance motor.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2009.05a
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• pp.388-391
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• 2009

In this paper, We observed spectral responsivity of general poly-cristalline silicon solar cell. This is very important to define solar cell's characteristics. So we tested two small modules that made of poly-cristalline silicon solar cells. We expect to the result of this experiment is useful for researching and measuring solar cell's characteristics.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05a
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• pp.85-87
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• 2004

Radiation technology is an effective way for regulating polymeric materials to physicochemical and mechanical properties. New polymeric hydrogels based on vinyl ethers have been synthesized by the ${\gamma}$-initiated polymerization method. In this paper, we have studied the effect of radiation on mechanical and electrochemical properties of new rubber-like polymeric composite materials based on poly (vinyl ether of ethyleneglycol: PVEEG).

• Proceedings of the KIEE Conference
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• 1993.07b
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• pp.1250-1252
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• 1993

Enhancement mode n-channel TFT leakage current(off current : $V_G<0$) that is little agreement on the conduction mechanism is major disadvantage of poly-silicon TFT in practical use, characteristic analysis and model ing. In this paper, new modeling of leakage current is proposed. The activation energy of leakage current, which is dependent on gate voltage, and leakage current dependent on poly silicon thickness are plausibly explained with this model. This model indicate that the reduction of leakage current is attributable to a decrease of maximum laterial electric field strength in the drain depletion region and to the density of trap.

• Coupled systems mechanics
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• v.2 no.3
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• pp.215-230
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• 2013

This paper investigates the pull-in instability of functionally graded poly-SiGe micro-beams under the combined electrostatic and intermolecular forces and temperature change. The exponential distribution model and Voigt model are used to analyze the functionally graded materials (FGMs). Principle of virtual work is used to derive the nonlinear governing differential equation which is then solved using differential quadrature method (DQM). A parametric study is conducted to show the significant effects of material composition, geometric nonlinearity, temperature change and intermolecular Casimir force.

• Membrane and Water Treatment
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• v.10 no.4
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• pp.251-257
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• 2019

Fabricating hydrophobic porous membrane is important for exploring the applications of membrane distillation (MD). In the present paper, poly(vinylidene fluoride) (PVDF) hollow fiber membrane was modified by coating polydimethylsiloxane (PDMS) on its surface. The effects of PDMS concentration, cross-linking temperature and cross-linking time on the performance of the composite membranes in a vacuum membrane distillation (VMD) process were investigated. It was found that the hydrophobicity and the VMD performance of the PVDF hollow fiber membrane were obviously improved by coating PDMS. The optimal PDMS concentration, cross-linking temperature and cross-linking time were 0.5 wt%, $80^{\circ}C$, and 9 hr, respectively.

• Journal of Electrochemical Science and Technology
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• v.10 no.2
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• pp.250-255
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• 2019

Poly(ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) show promise for improving the lithium ion battery safety. However, due to oxidation of the PEO group and corrosion of the Al current collector, PEO-based SPEs have not previously been effective for use in $LiCoO_2$ (LCO) cathode materials at room temperature. In this paper, a semi-interpenetrating polymer network (semi-IPN) PEO-based SPE was applied to examine the performance of a LCO/SPE/Li metal cell at different voltage ranges. The results indicate that the SPE can be applied to LCO-based lithium polymer batteries with high electrochemical performance. By using a carbon-coated aluminum current collector, the Al corrosion was mostly suppressed during cycling, resulting in improvement of the cell cycle stability.