• Transactions on Electrical and Electronic Materials
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• 제7권6호
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• pp.301-304
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• 2006

We studied the nematic liquid crystal (NLC) aligning capabilities using the new alignment material of the SiC (Silicon Carbide) thin film. The SiC thin film exhibits good chemical and thermal stability. The good thermal and chemical stability make SiC an attractive candidate for electronic applications. A vertical alignment of nematic liquid crystal by atomic beam exposure on the SiC thin film surface was achieved. The about $87^{\circ}$ of stable pretilt angle was achieved at the range from $30^{\circ}\;to\;45^{\circ}$ of incident angle. Consequently, the vertical alignment effect of liquid crystal electro-optical characteristic by the atomic beam alignment method on the SiC thin film layer can be achieved.

• 반도체디스플레이기술학회지
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• 제18권4호
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• pp.12-17
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• 2019

In this study, the Ag nano-dots structure and silicon nitride film were applied to the textured wafer surface to improve the light trapping effect of mono-crystalline silicon solar cell. Ag nano-dots structure was formed by performing a heat treatment for 30 minutes at 650℃ after the deposition of 10nm Ag thin film. Ag thin film deposition was performed using a thermal evaporator. The silicon nitride film was deposited by a Hot-wire chemical vapor deposition. The effect of light trapping was compared and analyzed through light reflectance measurements. Experimental results showed that the reflectivity increased by 0.5 ~ 1% under all nitride thickness conditions when Ag nano-dots structure was formed before nitride film deposition. In addition, when the Ag nano-dots structure is formed after deposition of the silicon nitride film, the reflectance is increased in the nitride film condition of 70 nm or more. When the HF treatment was performed for 60 seconds to improve the Ag nano-dot structure, the overall reflectance was improved, and the reflectance was 0.15% lower than that of the silicon nitride film-only sample at 90 nm silicon nitride film condition.

• 한국전기전자재료학회논문지
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• 제24권5호
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• pp.359-363
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• 2011

To integrate the sensor driver and logic circuits, fabricating down scaled transistors has been main issue. At this research, short channel effects were analyzed after n channel polycrystalline silicon thin film transistor was fabricated at high temperature. As a result, on current, on/off current ratio and transconductance were increased but threshold voltage, electron mobility and s-slope were reduced with a decrease of channel length. When carriers that develop at grain boundary in activated polycrystalline silicon have no gate biased, on current was increased with punch through by drain current. Also, due to BJT effect (parallel bipolar effect) that developed under region of channel by increase of gate voltage on current was rapidly increased.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 하계종합학술대회 논문집
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• pp.662-666
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• 1989

Pure mono Silane(Purity: 99.99%) was used as a thin film source and [$SiH_4$ + $H_2$ (5%)] + [$PH_3$ + $H_2$(0.05%)] mixed dilute gas was used for p-n junction diode. The substrate was P-type silicon wafer (p=$3{\Omega}$ cm) with the direction (100). The crystalline qualities of deposited thin film were investigated by the X-ray diffraction, RHEED and TED patterns and the voltampere characteristics of p-n junction diode was identified by I-V curve.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.296-298
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• 1997

The performance of thin film pressure sensors with polyimide and silicon oxide as a insulating layer between the stainless steel diaphragm and the Cu-Ni strain gauges is presented. The polyimide was spun on the stainless steel diaphragm and cured in an oven. The silicon oxide was deposited by rf sputtering. The thin film pressure sensor with silicon oxide as a insulating layer showed a better nonlinearity and a lower hysteresis.

• 한국전기전자재료학회논문지
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• 제11권4호
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• pp.255-260
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• 1998

Behavior of solid phase crystallizations (SPC) of RF sputtered and LPCVD amorphous hydrogenated silicon film were investigated. LPCVD films showed the higher degree of crystallinity and larger grain size than sputtered films. The applicable degree of crystallinity was also obtained from sputtered films. The deposition method of amorphous silicon film influenced the behavior of post annealing SPC. Observed degree of crystallinity of sputtered films strongly depended on the partial pressure of hydrogen in deposition. The higher deposition temperature of sputtering provided the better crystallinity after SPC. Due to the high degree of poly-crystallinity, the retardation of larger grain growth was observed on sputtering film.

• Current Photovoltaic Research
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• 제5권4호
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• pp.113-121
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• 2017

The researches on the silicon-based thin films are being actively carried out. The silicon-based thin films can be made as amorphous, microcrystalline and mixed phase and it is known that the optical bandgap can be controlled accordingly. They are suitable materials for the fabrication of single junction, tandem and triple junction solar cells. It can be used as a doping layer through the bonding of boron and phosphorus. The carbon and oxygen can bond with silicon to form a wide range of optical gap. Also, The optical gap of hydrogenated amorphous silicon germanium can be lower than that of silicon. By controlling the optical gaps, it is possible to fabricate multi-junction thin film silicon solar cells with high efficiencies which can be promising photovoltaic devices.

• 한국재료학회지
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• 제25권4호
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• pp.196-201
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• 2015

This paper presents the impact of partial shading on $CuIn_xGa_{(1-x)}Se_2(CIGS)$ photovoltaic(PV) modules with bypass diodes. When the CIGS PV modules were partially shaded, the modules were under conditions of partial reverse bias. We investigated the characterization of the bypass diode and solar cell properties of the CIGS PV modules when these was partially shaded, comparing the results with those for a crystalline silicon module. In crystalline silicon modules, the bypass diode was operated at a partial shade modules of 1.67 % shading. This protected the crystalline silicon module from hot spot damage. In CIGS thin film modules, on the other hand, the bypass diode was not operated before 20 % shading. This caused damage because of hotspots, which occurred as wormlike defects in the CIGS thin film module. Moreover, the bypass diode adapted to the CIGS thin film module was operated fully at 60% shading, while the CIGS thin film module was not operated under these conditions. It is known that the bypass diode adapted to the CIGS thin film module operated more slowly than that of the crystalline silicon module; this bypass diode also failed to protect the module from damage. This was because of the reverse saturation current of the CIGS thin film, $1.99{\times}10^{-5}A/cm^2$, which was higher than that of crystalline silicon, $8.11{\times}10^{-7}A/cm^2$.

• 한국전기전자재료학회논문지
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• 제27권1호
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• pp.39-44
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• 2014

Silicon nitride thin film deposited with Plasma Enhanced Chemical Vapor Deposition was treated by a nitrogen plasma generated by Inductively Coupled Plasma at room temperature. The treatment was investigated by Fourier Transform Infrared Spectroscopy and Atomic Force Microscopy on the surface at various RF source powers at two RF bias powers. The amount of hydrogen was reduced and the surface roughness of the films was decreased remarkably after the plasma treatment. In order to understand the causes, we analyzed the plasma diagnostics by Optical Emission Spectroscopy and Double Langmuir Probe. Based on these analysis results, we show that the nitrogen plasma treatment was effective in the improving of the properties silicon nitride thin film for flexible display.

• 한국결정성장학회지
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• 제5권1호
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• pp.67-77
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• 1995

태양전지가 시장성을 확보하는데 가장 중요한 요소는 전지의 가격이다. 기존의 결정질 실리콘 태양전지에서는 가격의 절반 정도가 웨이퍼가격이다. 결과적으로 이러한 가격을 줄이기 위해서 박막 제조 기술에 많은 노력이 집중되고 있으며 박막형 태양전지의 효율을 증가시키기 위한 많은 기술적인 발전이 되고 있다. 박막형 태양전지의 기술에 관한 기술 발전은 다결정 실리콘(p-Si), 비정질 실리콘(a-Si), $SuInSe_2$(CIS), CdTe 등에서 주로 이루어지고 있다. 본 논문은 박막형 태양전지 분야에 있어서의 최근 연구성과에 대해서 알아보았다.