• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.570-573
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• 2001

In this paper, GaN films have been grown on SiO$_2$/Si(100) substrates by RF magnetron sputtering. To obtain high quality GaN films, we used ZnO buffer layer and modified the process conditions. The charateristics of GaN films on RF power, substrate temperature and Ar/N$_2$gas ratio have been investigated by Auger electron spectroscopy and X-ray diffraction analysis. At RF power 150W, substrate temperature 500 $^{\circ}C$ and Ar/N$_2$=1:2 gas ratio, we could grow high quality GaN films. Through the atomic force microscope and photoluminescence analysises, it was observed that the crystallization of GaN films was improved with increasing annealing temperature and the optimal crystallization of GaN films was found at 1100 $^{\circ}C$ annealing temperature.

• 한국주조공학회지
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• 제5권3호
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• pp.13-18
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• 1985

Decarburization phenomena were investigated at $800^{\circ}C$ by the $PH_2O/PH_2$ + Ar gas mixture in the case iron range which contains Si, Mn and Cr as an alloying elements. Dissociation of cementite in a matrix which contains graphitizer as Si begins at the carbon rich cementite dendrite arms. Several primary austenite $({\gamma})$ skeletons are surrounded by those nucleated graphite nodules, and that forms a limited area of nucleation region. Decarburization reactions at $800^{\circ}C$ in Fe-C, Fe-Mn-C and Fe-Cr-C alloy are followed by parabolic rate law under the gas mixture of $PH_2O/PH_2=0.01$ and the modified rate const. ${\kappa}$ were in the range of $1{\sim}6{\times}10^{-10}cm^2/s$.

• E2M - 전기 전자와 첨단 소재
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• 제6권1호
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• pp.55-62
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• 1993

수소 관련된 species를 포함하지 않고 자기제한특성으로 초박막 성장을 용이하게 제어할 수 있는 N$_{2}$O 가스 분위기에서 실리콘의 산화는 질화된 산화막의 재산화공정 보다 훨씬 간단한 공정이다. N$_{2}$O산화로 형성된 Si-SiO$_{2}$ 계면에서 nitrogen-rich층은 산화막 구조를 강화할 뿐만 아니라 게이트 유전체의 질을 개선하고 산화율을 감소시키는 산화제의 확산 장벽으로 작용한다. 초박막 oxynitride 게이트 유전체가 종래의 열산화 방법으로 제작되었고 oxynitride막의 특성이 AES와 I-V 특성 측정의 결과를 분석하여 연구하였다.

• 반도체디스플레이기술학회지
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• 제21권2호
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• pp.45-50
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• 2022

The etching with high selectivity of silicon dioxide over silicon nitride is essential in semiconductor fabrication, and gas phase etch (GPE) can increase the competitiveness of the selective dielectric etch. In this work, GPE of plasma enhanced chemical vapor deposited SiO₂ was performed, and the effects of process parameters, such as temperature, partial pressure ratio, and gas supply cycle, are investigated in terms of etch rate and within wafer uniformity. Employing multiple regression analysis, the importance of each parameter elements is analyzed.

• 한국분말재료학회지
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• 제8권3호
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• pp.179-185
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• 2001

Through the observation of wear scar of two ceramic materials, microstructural wear mechanisms was investigated. As for the $Al_2O_3$-5 vol% SiC nanocomposite, the grain boundary fracture was suppressed by the presence of SiC nano-particles. The intragranular SiC particles have inhibited the extension of plastic deformation through the whole grain. Part of plastic deformation was accommodated around SiC particles, which made a cavity at the interface between SiC and matrix alumina. On the other hand, gas-pressure sintered silicon nitride showed extensive grain boundary fracture due to the thermal fatigue. The lamination of wear scar was initiated by the dissolution of grain boundary phase. These two extreme cases showed the importance of microstructures in wear behavior.

• 한국재료학회지
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• 제19권1호
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• pp.37-43
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• 2009

Silicon dioxide as gate dielectrics was grown at $400^{\circ}C$ on a polycrystalline Si substrate by inductively coupled plasma oxidation using a mixture of $O_2$ and $N_2O$ to improve the performance of polycrystalline Si thin film transistors. In conventional high-temperature $N_2O$ annealing, nitrogen can be supplied to the $Si/SiO_2$ interface because a NO molecule can diffuse through the oxide. However, it was found that nitrogen cannot be supplied to the Si/$SiO_2$ interface by plasma oxidation as the $N_2O$ molecule is broken in the plasma and because a dense Si-N bond is formed at the $SiO_2$ surface, preventing further diffusion of nitrogen into the oxide. Nitrogen was added to the $Si/SiO_2$ interface by the plasma oxidation of mixtures of $O_2/N_2O$ gas, leading to an enhancement of the field effect mobility of polycrystalline Si TFTs due to the reduction in the number of trap densities at the interface and at the Si grain boundaries due to nitrogen passivation.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.125-125
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• 2009

In this paper, we have investigated about MgO thin films on Si(100) substrate by RF magnetron Sputtering. MgO thin films were affected by RF input power, gas pressure, gas composition, and substrate temperatures. So, we focused on most effective RF input power in deposition condition. Thickness of MgO thin films was measured by surface profiler. And structural analysis carried out by X-ray Diffraction(XRD). physical characteristic and thickness of thin films changed with RF input power.

• 한국세라믹학회지
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• 제36권1호
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• pp.21-29
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• 1999

흑연 기판에 탄화규소 전환층을 형성하는데 있어서 기판의 밀도와 기공 크기 분포의 영향이 조사되었다. 전환층형성을 위한 화학 반응은 기판의 표면 또는 표면 하부에서 SiO 기체의 침투를 통해 이루어졌다. 전환 공정 동안 기판 표면에서의 충분한 양의 SiO 기체 침투 및 연속적인 화학반응에 요구되는 기공크기 분포는 1.0~10.0$\mu\textrm{m}$ 범위인 것으로 추정되엇다. 유한요소법에 의한 탄화규소 층의 응력 해석에서는 열적 불일치에 기인하는 잔류응력 분포를 나타냈다. 그러나. X-선 회절에 의해 탄화규소 층에서는 압축응력이 측정되었으며, 탄화규소 층에서의 잔류응력 분포에 대해 SiC 층과 흑연 기판간의 interlayer의 constraining 효과, 전환층의 치밀화 거동 및 입자성장에 의해 주로 영향받는 것으로 추정되었다.

• 한국산학기술학회논문지
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• 제20권4호
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• pp.497-502
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• 2019

금속산화물 나노구조물은 고감도 가스센서 및 대용량의 리튬이온 전지와 같은 첨단 응용 분야에 활용될 수 있는 유망한 소재로 알려져 있다. 본 연구에서는 산화주석(SnO) 나노구조물을 두 영역 전기로 장치를 이용하여 다양한 온도에서 Si 웨이퍼 기판 위에 성장시켰다. 원료물질인 이산화주석($SnO_2$) 파우더를 알루미나 도가니 속에 넣어서 $1070^{\circ}C$에서 기상화시켰으며, 이송가스인 고순도 Ar 가스를 1000 sccm으로 흘려주었다. SnO 나노구조물은 $350{\sim}450^{\circ}C$, 545 Pa 조건에서 30분 동안 Si 기판 위에 성장되었다. 성장된 SnO 나노구조물의 표면형상을 전계방출형 주사전자현미경(FE-SEM)과 원자힘 현미경(AFM)으로 조사하였다. 또한 성장된 SnO 나노구조물의 결정학적 특징을 Raman 분광학으로 조사하였다. 그 결과 성장된 산화주석은 SnO 상을 가지고 있었다. 기판의 온도가 증가함에 따라 성장된 SnO 나노구조물의 두께와 결정립의 크기도 $424^{\circ}C$까지는 증가하였다. $450^{\circ}C$에서 성장된 SnO 나노구조물은 복잡한 다결정 형태의 표면형상을 나타내었지만, $350{\sim}424^{\circ}C$ 범위에서 성장된 SnO 나노구조물은 기판에 나란한 형태의 단순한 결정구조를 나타내었다.

• 한국환경과학회지
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• 제22권1호
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• pp.83-89
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• 2013

Silicon carbide with aluminium oxide was used to remove the sulphur hexafluoride ($SF_6$) gas using microwave irradiation. The destruction and removal efficiencies (DREs) of $SF_6$ were studies as a function of various decomposition temperatures and microwave powers. The decomposition of $SF_6$ gas was analyzed using GC-TCD. XRD (X-ray powder diffraction) and XRF (X-ray Fluorescence Spectrometer) were used to characterize the properties of aluminum oxide. DREs of $SF_6$ were increased as the microwave powers were increased. Additive aluminium oxide on SiC increased the removal efficiencies and decreased the decomposition temperature. The XRD results show that the ${\gamma}-Al_2O_3$ was transformed to ${\alpha}-Al_2O_3$ during $SF_6$ decomposition by microwave irradiation. It was found that the best material to control $SF_6$ was SiC with $Al_2O_3$ 30 wt% in consideration of microwave energy consumption and $SF_6$ decomposition rate.