• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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• pp.137-137
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• 2008

In-situ doped polycrystalline 3C-SiC thin films were deposited by APCVD at $1200^{\circ}C$ using HMDS(hexamethyildisilane: $Si_2(CH_3)_6)$) as Si and C precursor, and 0 ~ 100 sccm $N_2$ as the dopant source gas. The peak of SiC is appeared in polycrystalline 3C-SiC thin films grown on $SiO_2$/Si substrates in XRD(X-ray diffraction) and FT-IR(Fourier transform infrared spectroscopy) analyses. The resistivity of polycrystalline 3C-SiC thin films decreased from 8.35 $\Omega{\cdot}cm$ with $N_2$ of 0 sccm to 0.014 $\Omega{\cdot}cm$ with 100 sccm. The carrier concentration of poly 3C-SiC films increased with doping from $3.0819\times10^{17}$ to $2.2994\times10^{19}cm^{-3}$ and their electronic mobilities increased from 2.433 to 29.299 $cm^2/V{\cdot}S$, respectively.

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2343-2347
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• 2013

In this work, manganese dioxide ($Mn_3O_4$)/carbon black (CB) composites (Mn-CBs) were prepared by an in situ coating method as electrical fillers and the effect of the Mn-CBs on the electrical performance of activated carbon (AC)-based electrodes was investigated. Structural features of Mn-CBs produced via in situ coating using a $KMnO_4$ solution were confirmed by XRD and TEM images. The electrical performances, including cv curves, charge-discharge behaviors, and specific capacitance of the ACs/Mn-CBs, were determined by cyclic voltammograms. It was found that the composites of $Mn_3O_4$ and CBs were successfully formed by in situ coating method. ACs/Mn-CBs showed higher electrical performance than that of AC electrodes fabricated with conventional CBs due to the pesudocapacitance reaction of manganese oxides in the aqueous electrolyte. Consequently, it is anticipated that the incorporation of $Mn_3O_4$ into CBs could facilitate the utilization of CBs as electrical filler, leading to enhanced electrochemical performance of AC electrodes for supercapacitors.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2009년도 정기총회 및 동계학술연구발표회
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• pp.204-205
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• 2009

The magnetic properties and structure of FeRh thin film pitaxially grown onto MgO(001) substrate were studied by MPMS(Magnetic Properties Measure System) and in-situ temperature synchrotron XRD(X-ray Diffraction). The transition temperature of FeRh thin films was around 380K. Both M-T curve and d-spacing changes correspond to each other very closely.

• 한국진공학회지
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• 제3권4호
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• pp.405-413
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• 1994

초고진공에서 기판 Si(111)-7$\times$7 위에 Ti:Si 또는 1:2의 조성비로 Ti와 Si을 동시증착한 후 in situ 열처리하여 TiSi2 박막을 에피택셜 성장시켰다 XRD와 XPS 분석결과 동시증착된 혼합 층에서 C49-TiSi2 박막의 성장은 핵형성에 의함을 확인하였으며 양질의 C49-TiSi2 박막은 Ti를 증착한후 Ti와 Si를 동시 증착한 (Ti+2Si)/(Ti)/Si(111)-7$\times$7구조의 시료를 초고진공에서 50$0^{\circ}C$에서 열처리하여 얻을수 있었다. 형성된 C49-TiSi2/Si(111)의 계면은 깨끗하였고 HRTEM 분석 결과 C49-TiSi2\ulcornerSi(111)의 계면은 약 10。 의 편의를 가지면서 TiSi2[211]∥Si[110] TiSi2(031)/Si(111) 의 정합성을 가졌으며 시료의 전 영 역에 에피택셜 성장되었다.

• 한국진공학회지
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• 제4권S1호
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• pp.81-86
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• 1995

Aluminum has been deposited selectively on TiN surfaces in the presence of Si, SiO2 from Dimethyethylamine Alane(DMEAA). The film properties of the deopsited AI film were determined by various methods(SEM, Auger, UV-photospectrometer, Four point-probe, XRD). The effect of in-situ H2 plasma precleaning was studied. The effect of gap distance, pressure and temperature on the properties(crystallinity, resistance, grain size, morphology) of AI film and on the growth rates was investigated. It was found that the plasma precleaning promotes the growth rate and there exists optimum thmperature for maximum growth rate.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2000년도 추계총회,초청강연,특별강연,연구발표회
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• pp.204.2-204
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• 2000

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1230-1231
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• 2008

The effect of content of $Al_2O_3+Y_2O_3$ sintering additives on the densification behavior, mechanical and electrical properties of the pressureless-sintered $SiC-ZrB_2$ electroconductive ceramic composites was investigated. The $SiC-ZrB_2$ electroconductive ceramic composites were pressureless-sintered for 2 hours at 1,700[$^{\circ}C$] temperatures with an addition of $Al_2O_3+Y_2O_3$(6:4 mixture of $Al_2O_3$ and $Y_2O_3$) as a sintering aid in the range of 8${\sim}$20[wt%]. Phase analysis of $SiC-ZrB_2$ composites by XRD revealed mostly of ${\alpha}$-SiC(6H), $ZrB_2$ and In Situ YAG($Al_5Y_3O_{12}$). The relative density, flexural strength, Young's modulus and vicker's hardness showed the highest value of 89.01[%], 81.58[Mpa], 31.437[GPa] and 1.34[GPa] for $SiC-ZrB_2$ composites added with 16[wt%] $Al_2O_3+Y_2O_3$ additives at room temperature respectively. Abnormal grain growth takes place during phase transformation from ${\beta}$-SiC into ${\alpha}$-SiC was correlated with In Situ YAG phase by reaction between $Al_2O_3$ and $Y_2O_3$ additive during sintering. Compositional design and optimization of processing parameters are key factors for controlling and improving the properties of SiC-based electroconductive ceramic composites. In this paper, it is convinced that ${\beta}$-SiC based electroconductive ceramic composites for heaters or ignitors can be manufactured by pressureless sintering.

• 한국광물학회지
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• 제18권4호통권46호
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• pp.289-299
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• 2005

알바이트 분말시료, 박편시료, TEM 시편용 시료를 이용하여 광학현미경 상에서 등온가열 실험을 수행하였다. 시료의 방향성은 광학현미경 및 XRD를 통하여 점검하였으며 TEM의 전자회절도형을 통해 확인하였다. 분말시료의 경우 $1030^{\circ}C$-12 hr에서, TEM 시편용 시료는 $1060^{\circ}C$-6 hr에서 부분 용융이 일어나며 이 이상의 온도에서는 용융으로 인한 시편두께 증가 및 비정질상으로의 변화로 인하여 알바이트 미세구조의 TEM 영상 획득이 어려웠다. 광학현미경과 TEM의 연계를 통한 알바이트 등온가열 실험 결과 알바이트 tweed 미세구조의 TEM 영상을 얻을 수 있는 최적 조건은 대기압 하에서는 $1050^{\circ}C$-12 hr로 파악되었다. 전자현미경 내 직접가열(in situ TEM heating) 실험의 경우 상기한 실험조건에 비해 고진공 상태임을 고려하면 $1050^{\circ}C$보다 다소 높은 온도에서 알바이트 tweed 미세구조를 직접 관찰할 수 있을 것으로 사료된다

• Journal of Electrochemical Science and Technology
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• 제1권2호
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• pp.85-91
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• 2010

We have studied the origin of an additional plateau of $Li_{4+x}Ti_5O_{12}$ (LTO) observed at 0.7 V (vs. Li/$Li^+$). Some LTO has to be discharged down to below 1.0 V forming two-stage plateau (1.5 V and 0.7 V) in order to obtain most of capacity while others could achieve the same level of capacity at higher potential (1.0 V vs. Li/$Li^+$) forming one plateau (1.5 V). The particle size effect has been investigated as a possible reason of this. The 0.7 V plateau was gradually elongated with increasing the particle size. The structural variations and kinetic behaviors during discharge were carefully examined by in-situ XRD technique and OCV measurement. According to structural and electrochemical verifications, the kinetic limitation of $Li^+$ insertion is responsible primarily for the two-stage plateau which is related to the particle size of LTO rather than the formation of new intermediate phase during discharge. Herein, we propose a possible reaction model to elucidate this abnormal behavior of LTO below 1.0 V (Li/$Li^+$).

• 한국재료학회지
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• 제8권10호
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• pp.912-917
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• 1998

화학적 산화막(SiOx)이 형성된 Si(100)기판 위에 Co-silicide의 형성과 계면 형상에 관한 연구를 하였다. 화학적 산화막은 과산화수소수(H2O2)의 인위적 처리에 의해 약 2nm을 형성시켰다. 그 위에 5nm 두께의 Co 박막을 전자빔 증착기에 의해 증착시킨 후 열처리하여 Co-silicide를 형성하였다. 화학적 산화막 위에서 Co-silicide 반응기구를 알아 보기 위해 $500^{\circ}C$-$900^{\circ}C$의 온도 범위에서 ex-situ와 in-situ 열처리를 하였다. 이와같이 형성된 Co-silicide 시편의 상형성, 표면 및 계면 형상, 그리고 화학적 조성을 XRD, SEM, TEM, 그리고 AES를 이용하여 분석하였다. 분석 결과 es-situ 열처리시 $700^{\circ}C$까지 CoSi2 상은 형성되지 않았고 Co의 응집화현상이 일어났다. $800^{\circ}C$ 열처리한 경우에는 CoSI2가 형성되었고 facet 현상이 크게 나타났으며 불연속적인 grain 들이 형성되었다. In-situ 열처리한 경우에는 저온에서 ($550 ^{\circ}C$)반응하여 Co-silicide가 형성되기 시작하였으며 $600^{\circ}C$부터는 facet에 의해 박막의 특성이 나빠지기 시작했다. $550^{\circ}C$에서 Co가 화학적 산화막 층을 통해 확산하여 균질한 Co-silicide를 형성하였다. 이와같이 형성된 균질한 실리사이드 층을 이용하여 다단계(55$0^{\circ}C$-$650^{\circ}C$-$800^{\circ}C$)열처리에 의해 균질한 다결정 CoSI2의 형성이 관찰되었다.