• JOURNAL OF ELECTRICAL WORLD
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• s.297
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• pp.66-72
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• 2001

1957년에 사이리스터가 발표된 이래 파워반도체디바이스(이하 ''파워디바이스''라 한다)의 발전과 더불어 이것을 사용하여 전력변환$\cdot$제어와 이를 응용한 파워일렉트로닉스 산업도 현저한 발전을 이루어 왔다. 21세기를 맞이하여 지구의 유한성을 강하게 인식하고 자원과 에너지를 고도이용하는 순환형 사회에로의 전환을 도모하는 기술혁신과 IT(정보기술)를 구사한 기술보급의 움직임이 활발해지고, 파워일렉트로닉스와 그 키파트인 파워디바이스가 수행하여야 할 역할은 점점 더 중요해지고 있다. 이와 같은 배경 하에서 파워디바이스는 인버터제어를 주목적으로 사이리스터, GTO(Gate Turn-off Thyristor), 바이폴라트랜지스터, MOSFET(Metal Oxide Silicon Field Effect Transistor)에서 IGBT(Insulated Gate Bipolar Transistor)에로 진전되고, 그 응용분야도 가전제품에서 OA, 산업, 의료, 전기자동차, 전철, 전력에 이르는 폭넓은 분야로 확대되었다. 현재 파워디바이스를 취급하는 전력의 범위는 수W의 스위칭 전원에서 GW급의 직류송전까지 9단위까지에 이르러 광범위한 전력 제어가 가능하게 되었다. 한편 응용의 중심이 되는 IGBT는, 고속화와 저손실화 및 파괴 내량의 향상을 지향한 개량을 거듭하여 제5세대제품이 나타나기 시작하였다. 또한 IGBT에 구동$\cdot$보호$\cdot$진단 회로 등을 넣어 모듈화한 IPM(Intelligent Power Module)이 그 편리성과 소형화를 특징으로 파워디바이스의 주역의 자리에 정착하였다. 가전$\cdot$산업$\cdot$자동차$\cdot$전철의 각 분야에서는 시장 니즈에 최적 설계된 IPM이 개발되게 되어 보다 더한 시장확대가 기대되고 있다. 또한 종래의 Si(실리콘)에 대신하는 반도체 재료로서 SiC(실리콘 카바이드 : 탄화규소)에 대한 기대가 크고 MOSFET나 SBD 등의 파워디바이스의 조기실용화에의 대처노력도 주목할 만하다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.9
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• pp.1226-1233
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• 2002

The purpose of the present study was to examine some basic aspects of laser chemical vapor deposition that will be ultimately utilized for solid freeform fabrication of three dimensional objects. Specifically, deposition of silicon carbide (SiC) using tetramethylsilane (TMS) as precursor was studied for a rod grown by $CO_2$laser-assisted chemical vapor deposition. First, temperature distribution for substrate was analyzed to select proper substrate where temperature was high enough for SiC to be deposited. Then, calculations of chemical equilibrium and heat and mass flow with chemical reactions were performed to predict deposition rates, deposit profiles, and deposit components. Finally, several rods were experimentally grown with varying chamber pressure and compared with the theoretical results.

• Journal of the Korean Ceramic Society
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• v.28 no.6
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• pp.429-436
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• 1991

Silicon carbide has been grown by a chemical vapor deposition (CVD) technique using CH3SiCl3 and H2 gaseous mixture onto a graphite substrate. Based on the thermodynamic equilibrium studies and the suggestion that the deposition rate of SiC is controlled by surface reaction theoretical kinetic equation for CVD of silicon carbide has been proposed. The proposed theoretical kinetic equation for CVD of silicon carbide agreed well with the experimental results for the variation of the deposition rate as a function of the partial pressure of reactant gases. The Vikers microhardness of the SiC layer was about 3000∼3400 kg/$\textrm{mm}^2$ at room temperature.

• Journal of the Korean Ceramic Society
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• v.37 no.6
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• pp.589-595
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• 2000

Densification behavior of SiC powder was investigated under cold compaction. A special form of the Cap model was proposed from experimental data of SiC powder under triaxial compression. To compare with experimental data of SiC powder under cold compaction, the proposed constitutive model was implemented into a finite element program (ABAQUS). Finite element calculations from the Cam-Clay model and the modified Drucker-Prager model were also compared with experimental data of SiC powder. The agreements between experimental data and finite element results obtained from the proposed constitutive model are reasonably good. In die pressing, finite element results obtained from the Cam-Clay model and the modified Drucker-Prager model, however, show lower average density of SiC powder compacts compared to experimental data.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1615-1620
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• 2003

The purpose of the study is not only to establish experimental system for laser chemical vapor deposition but also to find the characteristics of SiC rod growth that is the beginning step in developing technology of 3 dimensional prototyping with laser chemical vapor deposition. In this study, SiC rod was generated with varying TMS pressure for 5 minutes. Deposition rates with varying TMS pressure, shapes of rods, surface roughness and component organization were investigated, in particular.

• Proceedings of the KIPE Conference
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• 2018.07a
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• pp.336-337
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• 2018

전력 전자 시스템 내의 전도성 노이즈는 반도체 스위칭 소자의 고속 동작에 큰 영향을 받는다. 특히 실리콘 카바이드 (SiC) 등의 신소재 반도체 소자 (wide band-gap device, WBG device) 특유의 고속 dv/dt 특성이 전력전자모듈 (power electronics module, PEM) 내의 기생 용량 (parasitic capacitance)에 인가될 경우 상당한 전도성 노이즈의 원인이 되므로 이를 해결할 필요가 있다. 본 논문에서는 유전율이 낮은 재료를 PEM 내부에 사용함으로써 기생 용량을 줄이고, 따라서 공통 모드 전류의 발생 또한 최소화할 수 있는 설계를 제안한다. 제안된 PEM 설계 기법은 외부 필터를 필요로 하지 않으며, PEM 내의 스위칭 소자-방열 소자간 열저항 (thermal resistance)를 증가시키지 않으면서도 기생 용량을 최소화하여 노이즈를 억제한다. 제안된 방법으로 제작된 PEM을 1 kW 출력 100 kHz 스위칭 주파수의 강압형 dc-dc 컨버터에 적용하여 공통모드 전도성 전류가 줄어듬을 증명하였다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.4
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• pp.373-377
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• 2004

We have investigated the electrical characterization of metal-oxide-semiconductor (MOS) capacitors formed on the inductively coupled plasma (ICP) etch-damaged both n- and p-type 4H-SiC. We found that there was an effect of a sacrificial oxidation treatment on the etch-damaged surfaces. Current-voltage and capacitance-voltage measurements of these MOS capacitors were used and referenced to those of prepared control samples without etch damage. It has been found that a sacrificial oxidation treatment can improve the electrical characteristics of MOS capacitors on etch-damaged 4H-SiC since the effective interface density and fixed oxide charges of etch-damaged samples have been found to increase while the breakdown field strength of the oxide decreased and the barrier height at the SiC-SiO$_2$ interface decreased for MOS capacitors on etch-damaged surfaces.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.10
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• pp.817-821
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• 2000

In this work, we have investigated the dependence of annealing temperature(T$\_$a/) on optical and electrical properties of amorphous hydrogenated SiC(a-SiC:H) films. The a-SiC:H films were deposited on corning glass and p-type Si(100) wafer by PECVD (plasma enhanced vapor deposition) using SiH$_4$+CH$_4$+N$_2$ gas mixture. The experimental results have shown that the optical energy band gap(E$\_$opt/)of the thin films annealed at high temperatures have shown that the graphitization of carbon clusters and micro-crystalline silicon occurs. The current-voltage characteristics have shown good electrical properties at the annealed films.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.4
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• pp.280-284
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• 2011

Silicon carbide (SiC)-based gas sensors can be operated at very high temperatures. So far, catalytic metal-schottky diodes respond fast to a change between a reducing and an oxidizing atmosphere. Therefore SiC diodes have been suggested for high temperature gas sensor applications. In this work, the effect of reactivity of the catalytic surface on the 4H-SiC sensor-structures in 375 K~775 K have been studied and some fundamental simulations have also been performed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.4
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• pp.481-488
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• 2004

Laser chemical vapor deposition can be used as a new approach for a rapid prototyping technique. The purpose of the study is to fabricate several 3-dimensional objects that are relatively simple as well as to find the characteristics of SiC rod growth that is the first step in developing a new rapid prototyping technique with laser chemical vapor deposition. In the study, SiC rods were generated with varying precursor pressure for 5 minutes. Deposition rates with varying precursor pressure, shapes of rods, surface roughness and component organization were investigated, in particular. Finally, several simple objects like a branch or a propeller were successfully fabricated using laser chemical vapor deposition.