• 한국산학기술학회논문지
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• 제13권7호
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• pp.3160-3164
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• 2012

저온공정을 위해 스퍼터 방법에 의해 SiOC 박막을 증착하였으며, SiOC 박막 위에 투명전극을 제작하기 위해서 AZO박막과 ZnO 박막을 증착하였다. 박막의 광학적 특성은 PL 분석기와 스펙트라포토미터를 이용하였다. SiOC 박막은 n-type Si 위에 증착하였을 때 증착조건에 따라서 방사 효과가 다양하게 나타났으며, 두꺼운 박막에서 blue shit 현상이 나타났다. SiOC/Si 박막 위에 AZO 박막을 증착할 경우 빛의 흡수영역이 넓어졌다. 이러한 특성은 태양전지의 투명전극을 만들 경우 효율을 높일 수 있게 된다.

• 한국세라믹학회지
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• 제38권4호
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• pp.314-318
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• 2001

SiC-TiC composites have been fabricated by using a mechanochemical processing of a mixture of Si, Ti, and C at room temperature and subsequent hot pressing. TiC powders have been obtained by the mechanochemical processing of a mixture of Ti and C whereas SiC powders has not been obtained from a mixture of Si and C. By using the exothermic reaction between Ti and C, SiC-TiC powder could be obtained from the mixture of Si, Ti, and C using the mechanochemical processing for more than 12h. The X-ray diffraction analysis has shown that the powder subjected to the mechanochemical processing consisted of the particles having crystallite size below 10nm. Fully densified SiC-TiC composites have been obtained by hot-pressing of the powder at 1850$\^{C}$ for 3h and it has shown comparable mechanical properties to those of the SiC-TiC composites prepared from the commercially available SiC and TiC powders. Flexural strength of 560 MPa and fracture toughness of 4.8 MP$.$am$\_$1/2/ have been shown for the SiC-TiC composites with composition corresponding to 0.75:0.25:1 mole ratio of Si:Ti:C.

• Genomics & Informatics
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• 제11권1호
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• pp.55-57
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• 2013

Growing numbers of studies employ cell line-based systematic short interfering RNA (siRNA) screens to study gene functions and to identify drug targets. As multiple sources of variations that are unique to siRNA screens exist, there is a growing demand for a computational tool that generates normalized values and standardized scores. However, only a few tools have been available so far with limited usability. Here, we present siMacro, a fast and easy-to-use Microsoft Office Excel-based tool with a graphic user interface, designed to process single-condition or two-condition synthetic screen datasets. siMacro normalizes position and batch effects, censors outlier samples, and calculates Z-scores and robust Z-scores, with a spreadsheet output of >120,000 samples in under 1 minute.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 추계학술대회 논문집 학회본부
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• pp.240-242
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• 1994

Spectroscopic ellipsometry(SE) was employed to characterize the Si/$Si_{1-x}Ge_x$ heterostructure. The dielectric function spectrum of $Si_{1-x}Ge_x$ at an arbitrary x value in the spectral range of $1.5{\sim}4.5\;eV$ was computed by EMA (effective medium approximation) model using the available optical constants measured at a number of fixed x values of Ge composition. The thickness and the Ge composition of $Si_{1-x}Ge_x$ measured by SE was compared with those measured by RBS. DC bias effect on the $E_2$ peak of dielectric function spectra was studied.

• 한국세라믹학회지
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• 제24권2호
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• pp.155-160
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• 1987

본 연구는 제2보에서 합성한 $ZrSiO_4-Cd(SxSe_{1-x})$ 채료의 실용성을 조사하기 위하여 행하였다. 기존의 유명회사 제품의 채료와 본 합성채료를 비교 검사하였다. 우선 각각의 채료에 Frit를 적당한 비로 혼합하고 일정조성의 Tile에 시유하여 각각다른 온도(850-120$0^{\circ}C$)에서 소성한 다음 colorimeter를 사용하여 XYZ 주파장에 따른 색도도를 측정하였다. 또한 Munsell 계의 ISCC-NBS 색명법을 적용하여 색을 정량화 시킴으로서 채료의 적응성을 연구하였다. 그 결과 $ZrSiO_4-Cd(SxSe_{1-x})$ 채료는 V나 P 계통의 여타 채료와 같이 Frit 대 Stain의 비가 9:1의 최소비로 사용이 가능하며 100$0^{\circ}C$의 높은 온도에서도 밝은 적색으로 재현 될 뿐만 아니라 내산성이 강하고 고온에서 적응성이 있음을 확인하였다.

• Nuclear Engineering and Technology
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• 제49권6호
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• pp.1114-1124
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• 2017

Acceleration/preconditioning strategies available in the SCEPTRE radiation transport code are described. A flexible transport synthetic acceleration (TSA) algorithm that uses a low-order discrete-ordinates ($S_N$) or spherical-harmonics ($P_N$) solve to accelerate convergence of a high-order $S_N$ source-iteration (SI) solve is described. Convergence of the low-order solves can be further accelerated by applying off-the-shelf incomplete-factorization or algebraic-multigrid methods. Also available is an algorithm that uses a generalized minimum residual (GMRES) iterative method rather than SI for convergence, using a parallel sweep-based solver to build up a Krylov subspace. TSA has been applied as a preconditioner to accelerate the convergence of the GMRES iterations. The methods are applied to several problems involving electron transport and problems with artificial cross sections with large scattering ratios. These methods were compared and evaluated by considering material discontinuities and scattering anisotropy. Observed accelerations obtained are highly problem dependent, but speedup factors around 10 have been observed in typical applications.

• Transactions on Electrical and Electronic Materials
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• 제16권5호
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• pp.227-233
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• 2015

To reduce the cost of solar electricity, the crystalline-silicon (c-Si) photovoltaic industry is moving toward the use of thinner wafers (100 μm to 200 μm) to achieve a high efficiency. In this field, it is imperative to achieve an effective passivation method to reduce the electronic losses at the c-Si interface. In this article, we review the most promising surface passivation schemes that are available for high-efficiency solar cells.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2017년도 전력전자학술대회
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• pp.564-576
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• 2017

${\cdot}$ GaN E-HEMT provides superior performance vs. Si MOSFET or IGBT, and also superior performance vs. SiC, below ~1200V ${\cdot}$ GaN E-HEMT is replacing Si MOSFET and IGBT in major application segments, and Industry Adoption will accelerate ${\cdot}$ Technology advances in GaN E-HEMT have made high-current true Normally-Off devices available in current ranges from 7A to 250A ${\cdot}$ While GaN has improved Properties vs. SiC or Si, different types of GaN devices offer different levels of performance or robustness ${\cdot}$ JEDEC Industrial-Grade Qualification of GaN E-HEMTs has been achieved, and Automotive Qualification is in progress.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1338-1342
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• 2005

We have synthesized an $Eu^{2+}$-activated $Sr_3MgSi_2O_8$ blue phosphor and $Ba_2SiO_4$ green phosphor and $Ba^{2+}$ co-doped $Sr_3SiO_5$ red phosphor investigated an attempt to develop white LEDs by combining it with a GaN blue LED $chip(\lambda_{em}=405 nm)$. Three distinct emission bands from the GaN-based LED and the $(Sr_3MgSi_2O_8:Eu\; +\; Ba_2SiO_4:Eu\; +\; Ba^{2+}\; co-doped\; Sr_3SiO_5:Eu)$ phosphor are clearly observed at 460nm, 520 nm and at around 600 nm, respectively. These three emission bands combine to give a spectrum that appears white to the naked eye. Our results show that GaN (405 nm chip)-based $(Sr_3MgSi_2O_8:Eu\; +\; Ba_2SiO_4:Eu\; +\; Ba^{2+}\; co-doped\; Sr_3SiO_5:Eu) exhibits a better luminous efficiency than that of the industrially available product InGaN (460 nm chip)-based YAG:Ce.

• 한국재료학회지
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• 제20권9호
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• pp.463-466
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• 2010

We studied the initial reaction mechanism of Zn precursors, namely, di-methylzinc ($Zn(CH_3)_2$, DMZ) and diethylzinc ($Zn(C_2H_5)_2$, DEZ), for zinc oxide thin-film growth on a Si (001) surface using density functional theory. We calculated the migration and reaction energy barriers for DMZ and DEZ on a fully hydroxylized Si (001) surface. The Zn atom of DMZ or DEZ was adsorbed on an O atom of a hydroxyl (-OH) due to the lone pair electrons of the O atom on the Si (001) surface. The adsorbed DMZ or DEZ migrated to all available surface sites, and rotated on the O atom with low energy barriers in the range of 0.00-0.13 eV. We considered the DMZ or DEZ reaction at all available surface sites. The rotated and migrated DMZs reacted with the nearest -OH to produce a uni-methylzinc ($-ZnCH_3$, UMZ) group and methane ($CH_4$) with energy barriers in the range of 0.53-0.78 eV. In the case of the DEZs, smaller energy barriers in the range of 0.21-0.35 eV were needed for its reaction to produce a uni-ethylzinc ($-ZnC_2H_5$, UEZ) group and ethane ($C_2H_6$). Therefore, DEZ is preferred to DMZ due to its lower energy barrier for the surface reaction.