• 한국진공학회지
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• 제11권1호
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• pp.16-21
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• 2002

$Si_2H_6$가스를 이용한 LPCVD내에서의 실리콘의 선택적 에피텍시 성장을 $1000^{\circ}C$ 이하의 초청정 분위기하의 저온에서 수행하였다. HCI 첨가없이 초청정 공정으로 인한 양질의 에피텍시 Si층이 균일하게 얻어 졌으며, $SiO_2$위에 증착된 실리콘의 잠복기를 발견할 수 있었다. 단결정위의 에피텍시 층은 산화물 층위 보다 더 두껍게 증착되었다. 산소첨가로 잠복기가 20~30초간 증가하였다. 증착된 박막의 절단면과 표면 형상은 SEM으로 관찰되었으며, XRD를 통해 막질을 평가하였다.

• 한국진공학회지
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• 제5권2호
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• pp.133-138
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• 1996

단일 선구물질인 1, 3 -디실라부탄을 사용하여 고진공 하의 온도 영역 900-$1000^{\circ}C$에서 탄화규소 환충층이 형성된 Si(001) 기질 위에 입방형 탄화규소 박막을 적층 성장시켰다. 얻어진 탄화규소 박막의 화학량론적 비, 양질의 결정성 및 표면형태의 특성을 반사 고에너지 전자 회절, Xtjs 광전자 분광법, X선 회절, Xtjs 극접도, 주사 전자 현미경 및 투과 전자 현미경으로 확인하였다. 이들 결과로부터 단일 선구물질인 1, 3-디실라부탄이 입방구조를 가지는 탄화규소 박막의 적층 성장에 적절한 물질임을 밝혔다.

• 마이크로전자및패키징학회지
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• 제10권2호
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• pp.33-37
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• 2003

Si 태양전지의 효율 개선을 위해 textured 표면을 갖는 에피텍셜 베이스 전지(TSEB)를 제작하고 이의 전기광학적 특성을 조사하였다. 제작된 전지는 AM-1 100 mW/$cm^2$ 입사광 아래에서 개방전압이 0.62 V로, 단락전류가 40 mA로, 충실도가 0.7, 전력변환 효율이 16%로 나타났다. 본 연구에서 제안된 전지는 $P^-/P^+$ 에피구조에 의한 광흡수 영역에서 캐리어의 드리프트 이동과 효과적 배면전계의 형성, 그리고 buried contact을 통한 낮은 직렬저항 등으로 인해 고효율 Si 태양전지의 제작에 적합한 구조로 판단된다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.361.1-361.1
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• 2014

PbVO3 (PVO), a polar magnetic material considered as a candidate of multiferroic, has ferroelectricity along the c-axis and 2-dimensional antiferromagnetism lying in the in-plane through epitaxial growth [1,2]. PVO thin films were grown on LaAlO3 (001) substrates under reduction atmosphere from a stable Pb2V2O7 sintered target using pulsed laser deposition method. Epitaxial growth of the PVO films is possible only under Ar atmospheren with no oxygen partial pressure. X-ray diffraction was used to investigate the phase formation and texture of the films. We confirmed epitaxial growth of the PVO films with crystalline relationship of PbVO3[001]//LaAlO3[001] and PbVO3[100]//LaAlO3[100]. In addition, surface morphology of the films displays drastic changes in accordance with the growth conditions. Elongated PVO grains are related to the Pb2V2O7 pyrochlore structure. The relation between structural deformation and ferroelectricity in the PVO films was examined by local measurement of piezoresponse force microscopy.

• 한국재료학회지
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• 제16권1호
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• pp.30-36
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• 2006

A novel method was proposed to grow an epitaxial $CoSi_2$ on (100)Si substrate. A $CoN_x$ interlayer was deposited by reactive sputtering of Co in an Ar+$N_2$ flow. From the Ti/Co/$CoN_x$/Si structure, a uniform and thin $CoSi_2$ layer was epitaxially grown on (100)Si by annealing above $700^{\circ}C$. Two amorphous layers were found at the $CoN_x$/Si interface, where the top layer has a silicon nitride (Si-N) bonding state with some Co content and the bottom layer has a Co-Si intermixing state. The SiNx amorphous layer seems to play a critical role of suppressing the diffusion of Co into Si substrate for the direct formation of epitaxial $CoSi_2$.

• 반도체디스플레이기술학회지
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• 제15권1호
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• pp.41-46
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• 2016

In this study, gas flow and temperature distribution in the multi-wafer planetary CVD reactor for the Si epitaxial growth were analyzed. Although the structure of the reactor was simplified as the first step of the study, the three-dimensional analysis was performed taking all these considerations of the revolution of the susceptor and the rotation of satellites into account. From the analyses, a reasonable velocity field and temperature field were obtained. However, it was found that analyses including the upper structure of the reactor were required in order to obtain more realistic temperature results. DCS mole fraction above the satellite surface and the susceptor surface without satellite was compared in order to check the gas species mixing. We found that satellite rotation helped gases to mix in the reactor.

• Transactions on Electrical and Electronic Materials
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• 제1권3호
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• pp.18-22
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• 2000

In this work, we reported the sulfur compositional variation of ZnS$\_$x/Se$\_$1-x/ epitaxial layers with growth temperature and BEP ration of ZnX/Se/)P$\_$ZnS//P$\_$Se/) grown on GaAs substrates by molecular beam epitaxy. The sulfur composition of ZnSSe epitaxial layers was varied sensitively on the growth temperature and show different linear relationship with growth temperature and BEP ration of ZnS/Se(P$\_$ZnS//P$\_$Se/), which revealed -0.107 %$\^{C}$ at (P$\_$ZnS//P$\_$Se/)=0.30 and -0.052 %$\^{C}$ at (P$\_$ZnS//P$\_$Se/)=0.158 rspectively. A reference data for the accurate control of the sulfur composition and the growth of high quality ZnSSe/GaAs epitaxial layers was provided.

• Journal of Korean Vacuum Science & Technology
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• 제2권2호
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• pp.107-117
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• 1998

Epitaxial undoped and Sb-doped si films have been grown on Si(001) substrates at temperatures T between 80 and 750$^{\circ}C$ using energetic Si in ultra-high-vacuum Kr+-ion-beam sputter deposition(IBSD). Critical epitaxial thicknesses te, The average thickness of epitaxial layers, in undoped films were found to range from 8nm at Ts=80$^{\circ}C$ to > 1.2 ${\mu}$m at Ts=300$^{\circ}C$ while Sb incorporation probabilities $\sigma$sb varied from unity at Ts 550$^{\circ}C$ to 0.1 at 750$^{\circ}C$. These te and $\sigma$Sb values are approximately one and one-to-three orders of magnitude, respectively, higher than reported results achieved with molecular-beam epitaxy. Plan-view and cross-sectional transmission electron microscopy, high-resolution x-ray diffraction, channeling and axial angular-yield profiles by Rutherford back scattering spectroscopy for epitaxial Si1-x Gex(001) alloy films (0.15$\leq$x$\leq$0.30) demonstrated that the films are of extremely high crystalline quality. critical layer thicknesses hc the film thickness where strain relaxation starts, I these alloys wre found to increase rapidly with decreasing growth temperature. For Si0.70 Ge0.30, hc ranged from 35nm at Ts=550$^{\circ}C$ to 650nm at 350$^{\circ}C$ compared to an equilibrium value of 8nm.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.129.1-129.1
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• 2013

Atomically-thin graphene is the ideal model system for studying nanoscale friction due to its intrinsic two-dimensional anisotropy. Here, we report the reduced nanoscale friction of epitaxial graphene on SiC, investigated with conductive-probe atomic force microscopy/friction force microscopy in ultra-high vacuum. The measured friction on a buffer layer was found to be 1/8 of that on a monolayer of epitaxial graphene. Conductive probe atomic force microscopy revealed a lower conductance on the buffer layer, compared to monolayer graphene. We associate this difference in friction with the difference in total lateral stiffness. Because bending stiffness is associated with flexural phonons in two-dimensional systems, nanoscale frictional energy should primarily dissipate through damping with the softest phonons. We investigated the influence of hydrogen intercalation on the nanoscale friction. We found that the friction decreased significantly after hydrogen intercalation, which is related to loose contact between the graphene and the substrate that results in a lower bending stiffness.

• 한국전기전자재료학회논문지
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• 제16권7호
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• pp.573-578
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• 2003

Low temperature selective epitaxial growth of Si and SiGe has been obtained using an industrial single wafer chemical vapor deposition module operating at reduced pressure. Epitaxial Si and heteroepitaxial SiGe deposition with Ge content about 20 % has been studied as extrinsic base for self-aligned heterojunction bipolar transistors(HBTs), which helps to reduce the parasitic resistance to obtain higher maximum oscillation frequencies(f$\_$max/). The dependence of Si and SiGe deposition rates on exposed windows and their evolution with the addition of HCl to the gas mixture are investigated. SiH$_2$Cl$_2$ was used as the source of Si SEG(Selective Epitaxial Growth) and GeH$_4$ was added to grow SiGe SEG. The addition of HCl into the gas mixture allows increasing an incubation time even low growth temperature of 675∼725$^{\circ}C$. In addition, the selectivity is enhanced for the SiGe alloy and it was proposed that the incubation time for the polycrystalline deposit on the oxide is increased probably due to GeO formation. On the other hand, when only SiGe SEG(Selective Epitaxial Growth) layer is used for extrinsic base, it shows a higher sheet resistance with Ti-silicide because of Ge segregation to the interface, but in case of Si or Si/SiGe SEG layer, the sheet resistance is decreased up to 70 %.