• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05a
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• pp.198-201
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• 2004

We studied the nematic liquid crystal (NLC) aligning capabilities using the new alignment material of a SiO thin film. The homogenous alignment can be obtain어 using ion beam (IB) exposure on the SIO thin film, when positive type NLC ($Delta\varepsilon$>0) was injected However, the homeotropic alignment can be obtained using ion beam (IB) exposure on the SiO thin film, when negative type NLC ($\Delta\varepsilon$>0) was injected The LC aligning ability on the SiO thin film depends on the dielectric anisotropy type of LC. It will be discussed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05a
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• pp.94-97
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• 2004

In this paper, we investigate fringe-field switching (FFS) mode cell by the ion beam (IB) alignment method on the a-C:H thin film, to analyze electro-optical characteristics in this cell. We studied on the suitable inorganic thin film for fringe-field switching (FFS) cell and the aligning capabilities of nematic liquid crystal (NLC) using the new alignment material of a-C:H thin film An excellent voltage-transmittance (V-T) and response time curve of the IB-aligned FFS-LCD was observed with oblique IB exposure on the DLC thin films. Also, AC V-T hysteresis characteristics of the IB-aligned FFS-LCD with IB exposure on the DLC thin films is almost the same as that of the rubbing-aligned FFS cell on a polyimide (PI) surface.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.34D no.12
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• pp.14-21
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• 1997

This study was conducte dto fabricate 2GHz circulator using Ca,Sn substituted UIG(yttrium iron garnet)ceramics. When the electric, magnetic and microwave properties were measured in Ca, Sn substituted YIG, the measured perimittivity and perfmeability in microwave frequencies were 16.25, 0.8964. For $Y_{2.4}$C $a_{0.3}$A $n_{0.3}$F $e_{3.5}$A $l_{1.5}$ $O_{12}$ garnet ceramics sintered at 1400.deg. C, the ferrimagnetic resonance line width (.DELTA.H) at 10GHz was 53 Oe and saturation magnetization was 375G. The strip-line circulator was simulated with 3-D FEM (finite element method) software and designed at the center frequency of 2GHz. The fabricated strip-line junction circulator using above YIG ceramics had insertion loss of 1.271dB, return loss of 23.843dB, isolation of 21.751dB at the center frequency 1.855GHz.z.z.z.z.z.z.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.04a
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• pp.136-139
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• 2003

We studied the nematic liquid crystal (NLC) aligning capabilities using the new alignment material of a-C:H thin film as working gas at 30W rf bias condition. A high pretilt angle of about $5^{\circ}$ by ion beam(IB) exposure on the a-C:H thin film surface was measured. A good LC alignment by the IB alignment method on the a-C:H thin film surface was observed at annealing temperature of $250^{\circ}C$, and the alignment defect of the NLC was observed above annealing temperature of $300^{\circ}C$. Consequently, the high LC pretilt angle and the good thermal stability of LC alignment by the IB alignment method on the a-C:H thin film surface as working gas at 30W rf bias condition can be achieved.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.3
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• pp.255-259
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• 2006

In this paper, the inorganic-organic thin film encapsulation layer was newly adopted to protect the organic layer from moisture and oxygen. Using the electron beam, Sputter and Spin-Coater system, the various kinds of inorganic and organic thin-films were deposited onto the Ethylene Terephthalate(PET) and their interface properties between organic and inorganic layer were investigated. In this investigation, the SiON and Polyimide(PI) layer showed the most suitable properties. Under these conditions, the WVTR(water vapour transition rate) for PET can be reduced from level of $0.57\;g/m^2{\cdot}day$ (bare subtrate) to $1{\times}10^{-5}\;g/m^2{\cdot}day$ after application of a SiON and Polyimide layer. These results indicates that the SiON/PI/SiON/PI/PET barrier coatings have high potential for flexible organic light-emitting diode(OLED) applications.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.267-268
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• 2005

In this paper, the inorganic-organic thin film encapsulation layer was newly adopted to protect the organic layer from moisture and oxygen. Using the electron beam, Sputter and Spin-Coater system, the various kinds of inorganic and organic thin-films were deposited onto the Ethylene Terephthalate(PET) and their interface properties between organic and inorganic layer were investigated. In this investigation, the SiON and Polyimide(PI) layer showed the most suitable properties. Under these conditions, the WVTR(water vapour transition rate) for PET can be reduced from level of 0.57 g/$m^2$/day (bare subtrate) to $1{\times}10^{-5}$ /$m^2$/day after application of a SiON and Polyimide layer. These results indicates that the SiON/PI/SiON/PI/PET barrier coatings have high potential for flexible organic light-emitting diode(OLED) applications.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.8
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• pp.754-757
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• 2006

The inorganic multi-layer thin film encapsulation was newly adopted to protect the organic layer from moisture and oxygen. Using the electron beam, sputter, inorganic multi-layer thin-film encapsulation was deposited onto the Polyethylene Terephthalate (PET) and their interface properties between inorganic and organic layer were investigated. In this investigation, the SiON, $SiO_2$ and parylene layer showed the most suitable properties. Under these conditions, the WVTR for PET can be reduced from level of $0.57g/m^2/day$ (bare subtrate) to $1*10^{-5}g/m^2/day$ after application of a SiON and $SiO_2$ layer. These results indicates that the $PET/SiO_2/SiON/Parylene$ barrier coatings have high potential for flexible organic light-emitting diode(OLED) applications.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.12
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• pp.1085-1089
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• 2002

The circular cavity resonator which can measure the dielectric properties of dielectrics in the Ka-band(26.5GHz∼400Hz) frequency range was designed and fabricated. A structure of the resonator is divided into two equal parts of the length and the dielectric plate sample is placed between two halves. Exciting and detecting of the resonator is Performed by WR28 rectangular waveguides using Bethe's small hole coupling. The GaAs plate sample, whose performance is known to be 13 in millimeter wave range, was used for the verification of the performance of the fabricated circular cavity resonator In the measurement of GaAs single crystal using that resonator, the resonant frequency of the dominant TE$\sub$011/ mode, the permittivity and Q${\times}$f$\sub$0/ were measured as 26.69GHz, 12.9 and 124,000GHz, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.136-139
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• 2002

Previous valves have initial gap problem, high voltage or high pressure problem. In this paper, various micro valves with free floating structure have been fabricated and tested to solve the initial gap and high pressure problems. The paper presents how to etch Parylene-C which is a valve cap material without A1 mask layer. The maximum flow-rate of fabricated micro valve is$118{\mu\ell}$/min with $370{\mu}m$ orifice size and the leakage at the initial and reverse pressure is not observed.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.871-872
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• 2006

본 논문은 600 kJ SMES 모델 코일의 설계와 전자기력에 의한 모델코일의 스트레스의 해석에 관한 연구 결과를 나타낸다. 모델 코일의 설계에 적용된 초전도 선재는 77 K, 자기자계 하에서 115 A인 강화 선재이며, 모델 코일은 두 개의 팬케이크 코일로 구성한 모듈 코일 3개를 적층한 형태로 총 6개 더블 팬케이크 코일로 구성되어있다. 모델 코일의 임계전류는 전류를 인가하였을 때 코일에서의 최대 수직방향 자장을 이용해 Load Line을 나타내고, 이를 운전온도인 20 K에서의 $B-I_c$ 곡선에 적용하여 결정하였으며 236 A이다. 운전전류는 임계전류의 80%인 165 A로 결정하였으며, 이는 n-Value 손실을 고려한 값이다. 또한 해석적 방법을 이용해 코일에 전류를 인가하였을 때 전자기력에 의한 모델 코일의 radial stress와 hoop stress를 계산하여 나타내었다.