• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.368-369
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• 2008

This paper describes the mechanical properties of poly(polycrystalline) 3C-SiC thin film with various doping concentration, in which poly 3C-SiC thin film's mechanical properties according to the n-doping concentration 1%$(9.2\times10^{15}cm^{-3})$, 3%$(5.2\times10^{17}cm^{-3})$, and 5%$(6.8\times10^{17}cm^{-3})$ respectively was measured by nano indentation. In the case of $9.2\times10^{15}^{-3}$ n-doping concentration, Young's Modulus and hardness were obtained as 270 GPa and 30 GPa, respectively. When the surface roughness according to n-doping concentrations was investigated by AFM(atomic force microscope), the roughness of poly 3C-SiC thin film doped by 5% concentration was 15 nm, which is also the best of them.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제34회 춘계학술대회논문집
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• pp.437-440
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• 2010

이 논문은 발사체 노즐에 사용되는 내열성 재료인 C/SiC에 대한 이방성 물성을 예측하는 방법으로, 평면 방향의 실험 데이터를 이용해서 9개의 엔지니어링 물성을 간단하고 효과적으로 계산하는 준 이론적 접근에 대해 설명하였다. 이 방법은 C/SiC 복합재료를 직조 보강재의 굴곡율에 따라 세 층으로 이상화 하여, 고전 적층 평판이론으로 계산한다. 평면 방향으로 실행된 실험 데이터와 직조 구조물의 굴곡율을 초기 데이터로 이용하며, 측정이 어려운 두께 방향의 물성을 효과적으로 얻을 수 있었다. 예제를 통하여 이 방법의 유용성을 증명하였다.

• Nuclear Engineering and Technology
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• 제45권6호
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• pp.811-820
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• 2013

SiC has been under investigation as a potential cladding for LWR fuel, due to its high melting point and drastically reduced chemical reactivity with liquid water, and steam at high temperatures. As SiC is a brittle material its behavior during the reflood phase of a Loss of Coolant Accident (LOCA) is another important aspect of SiC that must be examined as part of the feasibility assessment for its application to LWR fuel rods. In this study, an experimental assessment of thermal shock performance of a monolithic alpha phase SiC tube was conducted by quenching the material from high temperature (up to $1200^{\circ}C$) into room temperature water. Post-quenching assessment was carried out by a Scanning Electron Microscopy (SEM) image analysis to characterize fractures in the material. This paper assesses the effects of pre-existing pores on SiC cladding brittle fracture and crack development/propagation during the reflood phase. Proper extension of these guidelines to an SiC/SiC ceramic matrix composite (CMC) cladding design is discussed.

• 한국진공학회지
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• 제12권S1호
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• pp.1-6
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• 2003

SiC-C films were deposited with r. f. magnetron sputtering on substrates followed by argon ion bombardment. These films were then permeated by hydrogen gas under the pressure of $3.23\times10^{7}$ Pa for 3 hours at temperature of 500K or bombarded with hydrogen ion beam at 5 keV and a dose of $1\times10^{18}$ ions/$\textrm{cm}^2$. SIMS, AES and XPS were used to analyze hydrogen related species, chemical bonding states of C, Si as well as contamination oxygen due to hydrogen participation in the SiC-C films in order to study the different behaviors of hydrogen in carbon-carbide films due to different hydrogen introduction. Related mechanism about the effects of hydrogen on the element of the SiC-C films was discussed in this paper.

• 방사성폐기물학회지
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• 제16권2호
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• pp.233-242
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• 2018

본 연구에서는 탄소강 심부시추공 처분용기가 가지는 고온에서의 물성 저하와 내부식성 문제 등을 해결하기 위하여, 열전도도가 우수한 SiC를 이용한 심부시추공 처분용기의 제작 가능성을 살펴보았다. 먼저 사용후핵연료 집합체 1다발을 수용할 수있는 심부시추공 처분용기를 설계하였으며, 설계된 처분용기는 내부 SiC 기밀용기와 취급 편의와 심부정치를 위한 외부 스테인리스 용기로 구성하였다. 그리고 SiC 세라믹 용기의 제작 가능성을 확인하기 위해, 1/3 규모의 소형 SiC 용기를 실제 제작하였다. 제작된 SiC 용기에서 시편을 추출하여 열전도도를 측정하였으며, KURT 지하 $70^{\circ}C$ 고온조건에서 3년간 내구성 시험도 실시하였다. 그 결과 SiC는 $100^{\circ}C$에서도 $70W{\cdot}m^{-1}{\cdot}K^{-1}$ 이상의 열전도도를 보였으며, 내구성 시험 후에도 변화가 전혀 보이지 않았다. 따라서 SiC는 높은 열전도도와 우수한 내부식성을 갖고 있어, 심부시추공 처분용기 재료로 적합하다고 보았다.

• 한국전기전자재료학회논문지
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• 제23권4호
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• pp.317-322
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• 2010

This paper reports the fabrication and characterization of surface micromachined poly 3C-SiC capacitive pressure sensors on silicon wafer operable in touch mode and normal mode for high temperature applications. FEM(finite elements method) simulation has been performed to verify the analytical mode. The sensing capacitor of the capacitive pressure sensor is composed of the upper metal and the poly 3C-SiC layer. Measurements have been performed in a temperature range from $25^{\circ}C$ to $500^{\circ}C$. Fabrication process of designed poly 3C-SiC touch mode capacitive pressure sensor was optimized and would be applicable to capacitive pressure sensors that are required high precision and sensitivity at high pressure and temperature.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1763-1765
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• 2000

This paper presents deposition and characterizations of microcrystalline silicon ($\mu$ c-Si:H) films prepared by hot wire chemical vapor deposition at substrate temperature at 300$^{\circ}C$. The flow rates of $SiH_4$ gas are critical parameter for the formation of Si films with microcrystalline phase. We could obtain $\mu$ c-Si:H with columnar grain structure and volume fraction of 75% without H2 dilution. The electronic properties, hydrogen bonding configurations, and $H_2$ concentration inside the films are also strongly affected by $SiH_4$ flow rate, which is provided in this paper.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 센서 박막재료 반도체재료 기술교육
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• pp.66-69
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• 2002

This paper presents deposition and characterizations of microcrystalline silicon$({\mu}c-Si:H)$ films prepared by hot wire chemical vapor deposition at substrate temperature below $300^{\circ}C$. The $SiH_{4}$ concentration$[F(SiH_{4})/F(SiH_{4})+F(H_{2})]$ is critical parameter for the formation of Si films with microcrystalline phase. At 6% of silane concentration, deposited intrinsic ${\mu}c-Si:H$ films shows sufficiently low dark conductivity and high photo sensitivity for solar cell applications. P-type ${\mu}c-Si:H$ films deposited by Hot-Wire CVD also shows good electrical properties by varying the rate of $B_{2}H_{6}$ to $SiH_{4}$ gas. The solar cells with structure of Al/nip ${\mu}c-Si:H$/TCO/glass was fabricated with single chamber Hot-Wire CVD. About 3% solar efficiency was obtained and applicability of HWCVD for thin film solar cells was proven in this research.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
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• pp.286-289
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• 2003

In the case of high voltage devices, junction termination plays an important role in determining the breakdown voltage of the device. The mesa junction termination has been demonstrated to yield nearly ideal breakdown voltage for 6H-SiC p-n junctions. However, such an approach may not be attractive because of the nonplanar surface, which is difficult to passivate. Moreover, In case of 4H-SiC, ideal breakdown voltage could not be achieved using mesa junction termination. For 4H-SiC planar junction termination technique is more useful one rather than mesa junction termination. In this paper, breakdown characteristics of the 4H-SiC device with planar junction termination, such as FLR(Field Limiting Ring), FP(Field Plate) and JTE(Junction Termination Extension), is presented. In the case of the FLR, breakdown voltage of 1800V is obtained. And breakdown voltage of 1000V and 1150V is also obtained for the case of FP and JTE case, respectively.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.99.2-99.2
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• 2010

This paper investigates the dependence of a-Si:H/c-Si passivation and heterojunction solar cell performances on various cleaning processes of silicon wafer and surface morphology. It is observed that passivation quality of a-Si:H thin-films on c-Si wafer highly depends on wafer surface conditions. The MCLT(Minority carrier life time) of wafer incorporating intrinsic (i) a-Si:H as a passivation layer shows sensitive variation with cleaning process and surface morpholgy. By applying improved cleaning processes and surface morphology we can obtain the MCLT of $200{\mu}sec$ after H-termination and above 1.5msec after i a-Si:H thin film deposition, which has implied open circuit voltage of 0.720V.