• ETRI Journal
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• 제26권3호
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• pp.257-261
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• 2004

We grew amorphous SiCN films by pulsed laser deposition using mixed targets. The targets were fabricated by compacting a mixture of SiC and $SiC-{Si_3}{N_4}$ powders. We controlled the film stoichiometry by varying the mixing ratio of the target and the target-to-substrate distance. The mixing ratio of the target had a dominant effect on the film composition. We consider the structures of the SiCN films deposited using 30~70 wt.% SiC in the target to be an intermediate phase of SiC and $SiN_x$. This provides the possibility of growing homogeneous SiCN films with a mixed target at a moderate target-to-substrate distance.

• Progress in Superconductivity
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• 제14권1호
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• pp.30-33
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• 2012

We have grown $MgB_2$ superconducting thin films on the SiC buffer layers by means of hybrid physical-chemical vapor deposition (HPCVD) technique. Prior to that, SiC was first deposited on $Al_2O_3$ substrates at various temperatures from room temperature to $600^{\circ}C$ by using the pulsed laser deposition (PLD) method in a vacuum atmosphere of ${\sim}10^{-6}$ Torr pressure. All samples showed a high transition temperature of ~40 K. The grain boundaries of $MgB_2$ samples with SiC layer are greater in amount, compare to that of the pure $MgB_2$ samples. $MgB_2$ with SiC buffer layer samples show interesting change in the critical current density ($J_c$) values. Generally, at both 5 K and 20 K measurements, at lower magnetic field, all $MgB_2$ films deposited on SiC buffer layers have low $J_c$ values, but when they reach higher magnetic fields of nearly 3.5 Tesla, $J_c$ values are enhanced. $MgB_2$ film with SiC grown at $600^{\circ}C$ has the highest $J_c$ enhancement at higher magnetic fields, while all SiC buffer layer samples exhibit higher $J_c$ values than that of the pure $MgB_2$ films. A change in the grain boundary morphologies of $MgB_2$ films due to SiC buffer layer seems to be responsible for $J_c$ enhancements at high magnetic fields.

• 한국세라믹학회지
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• 제38권4호
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• pp.365-369
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• 2001

플라즈마 화학증착법(PECVD)에 의해 실리콘 (100) 기판 위에 3C-SiC막을 증착하였다. 증착반응시 유입가스비, R$_{x}$[=CH$_4$/(CH$_4$+H$_2$)]에 따른 증착막의 결정성에 대해 검토하였다. 증착된 3C-SiC막의 결정성은 R$_{x}$ 값이 감소할수록 더욱 향상되었으며, 형성된 결정상은 (111) 면으로 최대의 우선배향성을 가졌다. Nanoindentation 방법을 이용하여 3C-SiC막의 압입깊이에 따른 경도 및 탄성계수를 측정하였으며, 유입가스비(R$_{x}$)의 변화에 따라서 막의 경도 및 탄성계수가 뚜렷이 변화하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 II
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• pp.995-998
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• 2003

This paper reports the correlation between dielectric constant and degree of amorphism of the hybrid type Si-O-C thin films. Si-O-C thin films were deposited by high density plasma chemical vapor deposition using bistrimethyl- silylmethane(BTMSM, $H_{9}$C$_3$-Si-C $H_2$-Si-C$_3$ $H_{9}$) and oxygen precursors with various flow rate ratio. As-deposited film and annealed films at 40$0^{\circ}C$ were analyzed by XRD. The Si-O-C thin films were amorphous from XRD patterns. For quantitative analysis, the diffraction pattern of the samples was transformed to radial distribution function by Fourier analysis, and then compared with each other. The degree of amorphism of annealed films was higher than that of as-deposited ones. The dielectric constant varied in accordance with flow rate ratio of precursors. The lowest dielectric constant was obtained from the as-deposited film which has the highest degree of amorphism after annealing.

• 대한전자공학회논문지SD
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• 제42권6호
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• pp.17-22
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• 2005

유무기 하이브리드 SiOC 박막은 차세대 유력한 저유전상수를 갖는 박막이다. SiOC 박막의 결합구조는 FTIR 분석기를 이용하여 화학적 이동이 일어나는 것을 확인하여 분석하였다. 유기화학분야에서의 일반적인 화학적 이동은 red shift에 해당하지만, 하이브리드 타입의 SiOC 박막은 red shift 뿐만 아니라 특이한 경우에 해당하는 blue shift도 관찰되었다. 화학적 이동의 원인은 전기음성도가 큰 원소가 주변에 존재하는 수소결합사이의 상호작용 때문인데, SiOC 박막에서 blue shift는 전자를 많이 포함하는 메틸그룹이 증가함으로 생기는 기공을 만드는 원인을 제공한다. SiOC 박막의 결합구조 역시 2가지 유형의 화학적 이동에 따라서 cross-link 구조와 case-link 구조의 두 가지 유형으로 나타난다. 유량비와 증착할 때 주어지는 열에너지에 따라서 두 가지 결합구조를 나타낸다. cross-link 구조와 cross-link breakage 구조는 박막의 유전상수가 낮아지는 원인 서로 다르며 화학적 물리적인 특성 또한 다르게 나타나는 것을 증명하고 있다. Si-O-C cross-link 구조는 red shift의 원인이 된 수소결합에 의한 원자사이의 길이가 길어지는 효과에 의해 표면접착력이 개선되며, 유전상수 역시 감소하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.331-332
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• 2007

Surface micromachined SiC devices have readily been fabricated from the polycrystalline (poly) 3C-SiC thin film which has an advantage of being deposited onto $SiO_2$ or $Si_3N_4$ as a sacrificial layer. Therefore, in this work, magnetron reactive ion etching process which can stably etch poly 3C-SiC thin films grown on $SiO_2$/Si substrate at a lower energy (70 W) with $CHF_3$ based gas mixtures has been studied. We have investigated the etching properties of the poly 3C-SiC thin film using PR/Al mask, according to $O_2$ flow rate, pressure, RF power, and electrode gap. The etched RMS (root mean square), etch rate, and etch profile of the poly 3C-SiC thin films were analyzed by SEM, AFM, and $\alpha$-step.

• 한국전기전자재료학회논문지
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• 제13권10호
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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.

• 한국표면공학회지
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• 제48권3호
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• pp.126-130
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• 2015

A high-pressure depletion method using plasma chemical vapor deposition (CVD) is often used to deposit hydrogenated microcrystalline silicon (${\mu}c-Si:H$) films of a low defect density at a high deposition rate. To understand proper deposition conditions of ${\mu}c-Si:H$ films for a high-pressure depletion method, Si films were deposited in a combinatorial way using a multi-hollow discharge plasma CVD method. In this paper the substrate temperature dependence of ${\mu}c-Si:H$ film properties are demonstrated. The higher substrate temperature brings about the higher deposition rate, and the process window of device quality ${\mu}c-Si:H$ films becomes wider until $200^{\circ}C$. This is attributed to competitive reactions between Si etching by H atoms and Si deposition.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2011년도 춘계학술대회 및 Fine pattern PCB 표면 처리 기술 워크샵
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• pp.171-171
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• 2011

Atmospheric pressure- plasma enhanced chemical vapor deposition(AP-PECVD)Processes are recognized as promising and cost effective methods for wide-area coating on sheets of steel, glass, polymeric web, etc. In this study, $SiO_xC_y$ thin films were deposited by using AP-PECVD with a dielectric barrier discharge(DBD). The characteristic of $SiO_xC_y$ thin films were investigated as afunction of the HMDSO/O2/He flow rate. And the moisture permeability of $SiO_xC_y$ thin films was studied. The $SiO_xC_y$ thin films were characterized by the Fourier-transformed Infrared(FT-IR) spectroscopy and also investigated by X-ray photo electron spectroscopy(XPS), Auger Electron Spectroscopy(AES). The moisture permeability of $SiO_xC_y$ thin films was investigated by $H_2O$ permeability tester Detailed experimental results will be demonstrated through th present work.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.235-235
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• 2009

This paper describes the influence of a polycrystalline (poly) 3C-SiC buffer layer on the surface acoustic wave (SAW) properties of poly aluminum nitride (AlN) thin films by comparing the center frequency, insertion loss, the electromechanical coupling coefficient ($k^2$), andthetemperaturecoefficientoffrequency(TCF) of an IDT/AlN/3C-SiC structure with those of an IDT/AlN/Si structure, The poly-AlN thin films with an (0002)-preferred orientation were deposited on a silicon (Si) substrate using a pulsed reactive magnetron sputtering system. Results show that the insertion loss (21.92 dB) and TCF (-18 ppm/$^{\circ}C$) of the IDT/AlN/3C-SiC structure were improved by a closely matched coefficient of thermal expansion (CTE) and small lattice mismatch (1 %) between the AlN and 3C-SiC. However, a drawback is that the $k^2(0.79%)$ and SAW velocity(5020m/s) of the AlN/3C-SiC SAW device were reduced by appearing in some non-(0002)AlN planes such as the (10 $\bar{1}$ 2) and (10 $\bar{1}$ 3) AlN planes in the AlN/SiC film. Although disadvantages were shown to exist, the use of the AlN/3C-SiC structure for SAW applications at high temperatures is possible. The characteristics of the AlN thin films were also evaluated using FT-IR spectra, XRD, and AFM images.