• 한국재료학회지
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• 제9권5호
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• pp.528-532
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• 1999

Y$_2$O$_3$films were grown on SiO$_2$-covered Si(111), and hydrogen-terminated Si(111), and hydrogen-terminated Si(111) substrates at 50$0^{\circ}C$ by ultrahigh vacuum ionized cluster beam deposition (UHV-ICB). The microstructures and growth behavior of these films have been investigated by transmission electron diffraction (TED) and high-resolution transmission electron microscopy(HREM). The TED results show that the $Y_2$O$_3$grown on the SiO$_2$-Si has the epitaxial relationship of (11-1)Y$_2$O$_3$∥(111)Si and [-110]Y$_2$O$_3$∥[-110]Si. The film on the H-Si substrate contains YS\ulcorner and amorphous YSi\ulcornerO\ulcorner layers at the interface, having the orientation relationship each other. For the YSi\ulcorner and the Si substrate, the relationship is (0001)YSi\ulcorner∥(111)Si and [1-210]YSi\ulcorner∥∥[-110]Si. For the $Y_2$O$_3$and the YSi\ulcorner ; the relationship is as follows: (11-1)Y$_2$O$_3$∥(0001)YSi\ulcorner and [-110]Y$_2$O$_3$∥[1-210]YSi\ulcorner(111)Y$_2$O$_3$∥(0001)YSi\ulcorner and [-110]Y$_2$O$_3$∥[1-210]YSi\ulcorner. Explanation is given to describe the formation mechanisms of the interfacial phases of SiO\ulcorner, YSi\ulcornerO\ulcorner and YSi\ulcorner. It is shown that the crystallinity of the $Y_2$O$_3$film on the SiO$_2$-Si(111) is better than that of $Y_2$O$_3$on H-Si(111).

• 한국세라믹학회지
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• 제39권4호
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• pp.413-419
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• 2002

$Al_2O_3$/TiC/SiC, $Al_2O_3$/SiC 및 $Al_2O_3$/TiC 복합체들을 고온가압소결로 제조하여 이들의 균열저항거동과 기계적 성질을 비교해 보았다. $Al_2O_3$에 $0.8{\mu}m$의 TiC가 30vol% 첨가된 $Al_2O_3$/TiC는 단일체 $Al_2O_3$와 비슷한 균열저항거동을 보이며 파괴인성은 전반적으로 10% 이내의 증가를 보이는데 그쳤지만 강도는 약 30% 증가하였다. $Al_2O_3$에 $3{\mu}m$ SiC가 30vol% 첨가된 $Al_2O_3$/SiC는 SiC 입자의 균열 접속으로 인해 증가하는 균열저항거동을 뚜렷이 보이면서 파괴인성이 긴 균열에서 약 75% 증가하였으나 강도는 다소 감소했다. $Al_2O_3$/TiC에 SiC 입자가 30 vol% 첨가된 $Al_2O_3$/TiC/SiC 복합체의 경우 단일체 $Al_2O_3$에 비해 긴 균열 거리에서 파괴인성이 50% 이상 증가된 6.6 MP${\cdot}\sqrt{m}$에 이르렀으며 강도 값도 약 20% 상승하였다. 그러나 큰 SiC 입자의 첨가로 인해 TiC 입자만 첨가된 $Al_2O_3$/TiC 복합체보다는 강도가 다소 낮았다. 또한 SiC 입자만 첨가된 $Al_2O_3$/SiC 복합체보다는 파괴인성이 다소 낮았는데, 이는 작은 TiC 입자들이 SiC 입계를 거칠게 만들어 균열접속을 일으키는 SiC 입자의 뽑힘 현상을 방해하였기 때문이다.

• 센서학회지
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• 제9권2호
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• pp.90-95
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• 2000

$Si_3N_4/SiO_2/Si_3N_4$/Si 판위에 MgO 박막을 성장하여 MgO 단결정과 결정배향성이 유사한 초전형 적외선 센서용 기판을 제작하였다. RF 마그네트론 스퍼터링법으로 MgO 박막을 성장하였고, 그 위에 Pt 하부전극과 PLT 박막을 성장시킨 후 c축 배향성을 조사하였다. $500^{\circ}C$의 기판온도와 30 mTorr의 분위기 압력 및 160 W의 RF power에서 성장된 MgO 박막이 단결정 MgO가 가지는 배향성 정도의 우수한 a축 배향성을 보였고, 그 위에 성장된 PLT 박막은 MgO 단결정 기판위에 성장된 것과 거의 회절강도 변화가 유사한 c축 배향성을 보였다.

• 센서학회지
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• 제4권2호
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• pp.58-63
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• 1995

$SiH_{4}$와 $NH_{3}$의 RF 글로우방전 분해에 의한 PECVD법으로 a-SiNx:H박막을 제조하고 기판온도, RF 전력, 그리고 $NH_{3}/SiH_{4}$ 유량비 등의 변화에 따른 a-SiNx:H 박막의 유전상수와 광학적 밴드갭 등을 조사하였다. a-SiNx:H막의 유전상수와 광학적 밴드갭은 기판온도, RF 전력 및 $NH_{3}/SiH_{4}$ 유량비 등의 증착변수에 따라 크게 변화하였다. 기판온도가 증가할수록 a-SiNx:H막의 유전상수는 증가하였으며 광학적 밴드갭은 감소하였다. 기판온도, RF 전력, 가스압력, $NH_{3}/SiH_{4}$ 유량비 및 두께를 각각 $250^{\circ}C$, 20 W, 500 mTorr, 10 및 $1500\;{\AA}$로 하였을 때 a-SiNx:H막의 유전상수, 절연파괴전장 및 광학적 밴드갭은 각각 4.3, 1 MV/cm 및 2.9 eV로 나타났다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1593-1595
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• 2002

Single crystal 3C-SiC(cubic silicon carbide) thin-films were deposited on Si(100) wafers up to a thickness of 4.3 ${\mu}m$ by APCVD method using HMDS(hexamethyildisilane) at $1350^{\circ}C$. The HMDS flow rate was 0.5 sccm and the carrier gas flow rate was 2.5 slm. The HMDS flow rate was important to get a mirror-like crystal surface. The growth rate of the 3C-SiC films was 4.3 ${\mu}m/hr$. The 3C-SiC epitaxial films grown on Si(100) were characterized by XRD, AFM, RHEED, XPS and raman scattering, respectively. The 3C-SiC distinct phonons of TO(transverse optical) near 796 $cm^{-1}$ and LO(longitudinal optical) near $974{\pm}1cm^{-1}$ were recorded by raman scattering measurement. The hetero-epitaxially grown films were identified as the single crystal 3C-SiC phase by XRD spectra($2{\theta}=41.5^{\circ}$).

• 센서학회지
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• 제16권4호
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• pp.319-323
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• 2007

This paper describes the mechanical characteristics of poly 3C-SiC thin films grown on Si wafers with thermal oxide. In this work, the poly 3C-SiC thin film was deposited by APCVD method using only Ar carrier gas and single precursor HMDS at $1100^{\circ}C$. The elastic modulus and hardness of poly 3C-SiC thin films were measured using nanoindentation. Also, the roughness of surface was investigated by AFM. The resulting values of elastic modulus E, hardness H and the roughness of the poly 3C-SiC film are 305 GPa, 26 GPa and 49.35 nm respectively. The mechanical properties of the grown poly 3C-SiC film are better than bulk Si wafers. Therefore, the poly 3C-SiC thin film is suitable for abrasion, high frequency and MEMS applications.

• 한국진공학회지
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• 제17권2호
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• pp.130-137
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• 2008

$La_{0.7}Sr_{0.3}MnO_3$ 박막을 rf 마그네트론 스퍼터를 이용하여 챔버 내 산소가스유량비를 0, 40, 80 sccm 으로 조절하고 후열처리 공정 없이 기판온도를 $350^{\circ}C$로 유지하면서 $SiO_2$/Si(100) 및 Si(100) 기판에 증착하였다. 증착된 $La_{0.7}Sr_{0.3}MnO_3$ 박막은 $SiO_2$/Si(100), Si(100) 기판 모두 (100), (110), (200)면을 갖는 polycrystalline 상태였으며, oxygen flow rate이 증가함에 따라 박막의 grain size가 증가하였다. 증가되는 grain size로 인하여 grain boundary가 감소하였고 따라서 높은 oxygen flow rate에서 증착된 박막은 면저항이 감소하는 현상을 나타내었다. $SiO_2$/Si 기판과 Si 기판에 증착된 LSMO 박막의 TCR 값은 약 -2.0 $\sim$ -2.2%를 나타내었다.

• 한국세라믹학회지
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• 제53권1호
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• pp.87-92
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• 2016

Due to its stability at high temperature and its layered structure, $Ti_3SiC_2$ MAX phase was considered to the interphase of $SiC_f/SiC$ composite. In this study, $Ti_3SiC_2$ MAX phase powder was deposited on SiC fiber via the electrophoretic deposition (EPD) method. The Zeta potential of the $Ti_3SiC_2$ suspension with and without polyethyleneimine as a dispersant was measured to determine the conditions of the EPD experiments. Using a suspension with 0.03 wt.% ball milled $Ti_3SiC_2$ powder and 0.3 wt.% PEI, $Ti_3SiC_2$ MAX phase was successfully coated on SiC fiber with an EPD voltage of 10 V for 2 h. Most of the coated $Ti_3SiC_2$ powders are composed of spherical particles. Part of the $Ti_3SiC_2$ powders that are platelet shaped are oriented parallel to the SiC fiber surface. From these results we expect that $Ti_3SiC_2$ can be applied to the interphase of $SiC_f/SiC$ composites.

• 한국전기전자재료학회논문지
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• 제23권6호
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• pp.487-490
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• 2010

This paper describes the elecrtical and optical characteristics of $N_2$ doped porous 3C-SiC films. Polycrystalline 3C-SiC thin films are anodized by $HF+C_2H_5OH$ solution with UV-LED exposure. The growth of in-situ doped 3C-SiC thin films on p-type Si (100) wafers is carried out by using APCVD (atmospheric pressure chemical vapor deposition) with a single-precursor of HMDS (hexamethyildisilane: $Si_2(CH_3)_6)$. 0 ~ 40 sccm $N_2$ was used for doping. After the growth of doped 3C-SiC, porous 3C-SiC is formed by anodization with $7.1\;mA/cm^2$ current density for anodization time of 60 sec. The average pore diameter is about 30 nm, and etched area is increased with $N_2$ doping rate. These results are attributed to the decrease of crystallinity by $N_2$ doping. Mobility is dramatically decreased in porous 3C-SiC. The band gaps of polycrystalline 3C-SiC films and doped porous 3C-SiC are 2.5 eV and 2.7 eV, respectively.

• 한국세라믹학회지
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• 제36권10호
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• pp.1007-1015
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• 1999

The Si3N4 composites reinforced with carbon-coated SiC whiskers were fabricated by hot-pressing at 180$0^{\circ}C$ for 2 hours to examine the effects of carbon-coated whiskers on the mechanical properties of SiC whisker reinforced Si3N4 composites. The flexural strength of the Si3N4 composites and Si3N4 monolith respectively. The weak interfacial bond between carbon-coated SiC whiskers and Si3N4 matrix which enhances the crack deflection and whisker pull-out could contribute to the improvement of mechanical properties of the composites.