• 한국전기전자재료학회논문지
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• 제36권1호
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• pp.29-35
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• 2023

Herein we investigated the effect of the conductive agent on the electrochemical performance of the SiOx anode. SiOx anodes have a relatively low volume expansion (~160%) compared to Pure-silicon, but have a problem in that they have a poor electrical conductivity characteristic. In this study, physical and electrochemical measurements were performed using two 0-dimensional amorphous carbon conductive agents with different crystallinity and surface area. The crystal structure of the conductive agents and the local graphitization degree were analyzed through XRD and Raman, and the surface area of the particles was observed through BET. In addition, the electrical performance according to the graphitization degree of the conductive agents was confirmed through a 4-point probe. As a result of the electrochemical cycle and rate performance, it was confirmed that the performance of SiOx using a conductive agent having a low graphitization degree and a high surface area was improved. The results in this study suggest that the graphitization degree and surface area of the amorphous carbon conductive agent may play an important role in the SiOx electrode.

• 대한전자공학회논문지
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• 제24권3호
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• pp.453-458
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• 1987

Amorphous silicon thin-film transtors (TFT's) have been designed and fabricated on glass substrates. The hydrogenated amorphous silicon (a-Si:H) thin-film has been deposited by decomposing silane(SiH4) in hydorgen ambient by rf glow discharge method. Amorphous silicon nitride(a-Si:H) has been chosen as the gate dielectric material. It has been prepared by decomposing the mixed gas of silane(SiH4) and ammonia(NH3). The electrical properties and performance characteristics of the thin-film transistrs have been measured and compared with the requirements for the switching elements in liquid crystal flat panel display. The results show that liquid crystal flat panel displays can be fabricated using the thin-film transistors described in this paper.

• Journal of Ceramic Processing Research
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• 제13권spc2호
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• pp.336-340
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• 2012

Wide band gap p-type hydrogenated amorphous silicon oxide (a-SiO:H) buffer layer has been used at the interface of transparent conductive oxide (TCO) and hydrogenated amorphous silicon (a-Si:H) p-type layer of a p-i-n type a-Si:H solar cell. Introduction of 5 nm thick buffer layer improves in blue response of the cell along with 0.5% enhancement of photovoltaic conversion efficiency (η). The cells with buffer layer show higher open circuit voltage (Voc), fill factor (FF), short circuit current density (Jsc) and improved blue response with respect to the cell without buffer layer.

• 한국표면공학회지
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• 제35권3호
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• pp.133-140
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• 2002

The Ti-Si-N coating layers were synthesized on SKD 11 steel substrate by a DC reactive magnetron co-sputtering technique with separate Ti and Si targets. The high resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS) analyses for the coating layers revealed that microstructure of Ti-Si-N layer was nanocomposite, consisting of nano-sized TiN crystallites surrounded by amorphous $Si_3$$N_4$ phase. The highest hardness value of about 39 GPa was obtained at the Si content of ~11at.%, where the microstructure had fine TiN crystallites (about 5nm in size) dispersed uniformly in amorphous matrix. As the Si content in Ti-Si-N films increased, the TiN crystallites became from aligned to randomly oriented microstructure, finer, and fully penetrated by amorphous phase. Free Si appeared in the layers due to the deficit of nitrogen source at higher Si content. Friction coefficient and wear rate of the Ti-Si-N coating layer significantly decreased with increase of relative humidity. The self-lubricating tribe-layers such as $SiO_2$ or (OH)$Si_2$ seemed to play an important role in the wear behavior of Ti-Si-N film against steel.

• 한국광물학회지
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• 제25권4호
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• pp.271-282
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• 2012

비정질 실리카겔은 Si와 O로 이루어진 가장 간단한 화합물로서, 표면에 다양한 구조의 물과 수산기, 그리고 합성과정에서 형성된 유기 리간드(ligand)를 함유하고 있어, 지권, 수권, 그리고 생물권의 상호작용을 이해하는 모델 시스템으로서 의미를 갖는다. 본 연구에서는 $^{17}O$ NMR 분광분석을 통해 비정질 실리카겔의 Si-O-Si와 Si-OH 산소 원자환경의 차이를 규명하고자 하였다. 이를 위해 $SiCl_4$의 수화반응을 통해 $^{17}O$이 집적된 비정질 실리카겔을 합성하였다. $^1H$과 $^{29}Si$ NMR 분광분석 결과, 비정질 실리카겔 표면에는 다양한 수소결합 세기를 가진 물과 수산기 이외에, Si-$O{\cdots}R$ 형태의 유기 리간드가 존재함을 확인하였다. 이와 같은 유기 리간드는 에탄올 또는 증류수를 이용해 비정질 실리카겔을 초음파 세척함으로써 상당부분 제거 가능하다. $^{17}O$ NMR 분광분석 결과, 짧은 펄스 길이($0.175{\mu}s$)를 이용한 $^{17}O$ NMR 스펙트럼에서 Si-O-Si와 Si-OH 산소원자 환경이 거의 구분되지 않고 나타나는 반면, 특정 실험조건($2{\mu}s$ 펄스길이)의 $^{17}O$ NMR 스펙트럼에서는 약 0 ppm에서 빠른 동역학적 특성을 가지는 Si-OH로 추정되는 피크가 관찰되었다. 이 피크는 비정질 실리카겔 표면의 유기 리간드가 제거됨에 따라 더 뚜렷하게 관찰되며, 이는 유기 리간드와 비정질 실리카의 산소원자 사이의 상호작용이 존재함을 지시한다. 이와 같은 상호작용은 비정질 실리카겔 표면의 수산기의 원자구조에 대한 정보를 제공하며, 이를 통해 규산염 지구물질의 탈수반응 기작에 대한 이해를 고양시킬 수 있다. 따라서 궁극적으로 지구물질의 탈수반응에 기인하여 일어나는 섭입대의 중간깊이(약 70~300 km)에서 일어나는 지진의 미시적인 원인에 대한 실마리를 제시할 것으로 기대된다.

• 한국결정성장학회지
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• 제30권6호
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• pp.271-276
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• 2020

본 연구에서는 유기 규소 폴리머(organosilicon polymer)인 폴리카보실란(polycarbosilane, PCS)을 사용하여 비정질 탄화규소 블록을 제조를 진행하였다. 다양한 형상의 치밀한 탄화규소 블록은 큐어링된 PCS 미세분말을 일축가압성형기를 통해 2~8 ton 하중을 가한 후 1100℃, 1200℃, 1300℃, 1400℃의 열처리 과정을 거쳐 제조되었으며, 물리적 화학적 특성 분석을 위해 열중량분석기(TGA), 주사전자현미경(SEM), 에너지분광분석법(EDS), 만능시험기(UTM)을 이용하였다, 제조된 탄화규소 성형체는 열분해 온도가 증가함에 따라 SiO와 CO 가스로의 분해가 발생하였고, 비정질의 구조에서 β-SiC 결정입자가 성장함을 보였다. 또한, 밀도와 굴곡강도는 1100℃의 열분해 온도에서 제조된 탄화규소 성형체가 1.9038 g/㎤과 6.189 MPa으로 가장 높았다. 제조된 비정질 탄화규소 블록은 이전에 보고된 마이크로파 도움 발열체와 같이 다른 분야에 적용 가능할 것으로 기대된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1984년도 하계학술회의논문집
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• pp.202-204
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• 1984

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2014년도 추계학술대회 논문집
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• pp.304-304
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• 2014

Quaternary Ti-Al-Si-N films were deposited on WC-Co substrates by a hybrid deposition system of arc ion plating (AIP) method for Ti-Al source and DC magnetron sputtering technique for Si incorporation. The synthesized Ti-Al-Si-N films were revealed to be composites of solid-solution (Ti,Al)N crystallites and amorphous $Si_3N_4$ by instrumental analyses. The Si addition in Ti-Al-N films affected the refinement and uniform distribution of crystallites by percolation phenomenon of amorphous silicon nitride, similarly to Si effect in TiN film. As the Si content increased up to about 9 at.%, the hardness of Ti-Al-N film steeply increased from 30 GPa to about 50 GPa. The highest microhardness value (~50 GPa) was obtained from the Ti-Al-Si-N film having the Si content of 9 at.%, the microstructure of which was characterized by a nanocomposite of $nc-(Ti,Al)N/a-Si_3N_4$.

• 한국세라믹학회지
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• 제53권6호
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• pp.610-614
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• 2016

Tyranno SA (SiC-polycrystalline fiber, Ube Industries Ltd.) shows excellent heat-resistance up to $2000^{\circ}C$ with relatively high mechanical strength. This fiber is produced by the conversion process from a raw material (amorphous Si-Al-C-O fiber) into SiC-polycrystalline fiber at very high temperatures over $1500^{\circ}C$ in argon. In this conversion process, the degradation reaction of the amorphous Si-Al-C-O fiber accompanied by a release of CO gas for obtaining a stoichiometric composition and the subsequent sintering of the degraded fiber proceed. Furthermore, vaporization of gaseous SiO, phase transformation and active diffusion of the components of the Si-Al-C-O fiber competitively occur. Of these changes, vaporization of the gaseous SiO during the conversion process results in an abnormal SiC-grain growth and also leads to the non-stoichiometric composition. However, using a modified Si-Al-C-O fiber with an oxygen-rich surface, vaporization of the gaseous SiO was effectively prevented, and then consequently a nearly stoichiometric SiC composition could be obtained.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 추계학술대회
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• pp.560-560
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• 2006