• Korean Chemical Engineering Research
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• 제55권2호
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• pp.275-278
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• 2017

Heterogeneous semiconductor composites have been widely used to establish high-performance microelectronic or optoelectronic devices. During a deposition of silicon atoms on silicon/germanium compound surfaces, germanium (Ge) atoms are segregated from the substrate to the surface and are mixed in incoming a silicon layer. To suppress Ge segregation to obtain the interface sharpness between silicon layers and silicon/germanium composite layers, approaches have used silicon hydride gas species. The hydrogen atoms can play a role of inhibitors of silicon/germanium exchange. However, there are few kinetic models to explain the hydrogen effects. We propose using segregation probability which is affected by hydrogen atoms covering substrate surfaces. We derived the model to predict the segregation probability as well as the profile of Ge fraction through layers by using chemical reactions during silicon deposition.

• 한국결정성장학회지
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• 제18권5호
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• pp.195-199
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• 2008

반도체용 규소 원료는 11 N급의 고순도이나 가격이 고가이고 또한 생산이 제한되어서 폭발적인 태양전지의 수요를 따르지 못하고 있어 저급(5$\sim$6 N)의 UMG(Upgraded Metallurgical Grade)를 사용하자 하는 노력이 진행 중이다. 이 5$\sim$6 N급에서는 dopant 원소인 붕소(B)외 인(P)의 농도가 1 ppm 이상 존재한다. 이들 원료를 사용하여서 결정 성장을 하였을 경우에 존재하는 여러 불순물들의 편석계수(segregation coefficient)를 활용하여 화학적, 전기적 성질을 예상 하여본 결과 결정성장 초기에는 붕소(B)의 농도가 인(P) 보다 높아 p영역이 발생하고 후반부에는 인의 농도가 붕소 보다 높아 n 형 기판이 생성됨을 보았다. 또한 응고속도를 조절하여 여러 불순물을 제거하고자 히는 노력은 편식계수가 적은 금속 일소들의 제거에는 효과적이나 편석계수가 큰 붕소와 인의 제거에는 효과가 크지 않음을 예상 할 수 있다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.917-920
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• 2001

Effects of addition of manganese and final reduction on segregation behavior of sulfur and final mangetic induction during final annealing have been investigated in the 300 ppm sulfur-contained 3% silicon-iron alloy strips with or without manganese. At the same concentration of sulfur, lower final reduction is favorable for final Goss texture. This is because the probability that the initial Goss grains survive under the highly segregated sulfur atmosphere and grow selectively within the segregated sulfur-free time range becomes higher. In the case of 3% silicon-iron with manganese, much lower magnetic induction was obtained, although the weak final reduction of 30% is given to the alloy, comparative to the 40%. This is because MnS particles acted as an reducer in the primary grain size.

• 한국결정성장학회지
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• 제18권5호
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• pp.191-194
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• 2008

We will focus on the horizontal Bridgman growth system to analyze the transport phenomena numerically, because the simple furnace system and the confined growth environment allow for the precise understanding of the transport phenomena in solidification process. In conventional melt growth process, the dopant concentration tends to vary significantly along the crystal. In this work, we propose the modification of crucible geometry for improving the productivity of silicon single-crystal growth by controlling axial specific resistivity distribution. Numerical analysis has been performed to study the transport phenomena of dopant impurities in conventional and proposed Bridgman silicon growth using the finite element method and implicit Euler time integration. It has been demonstrated using mathematical models and by numerical analysis that proposed method is useful for obtaining crystals with superior uniformity along the growth direction at a lower cost than can be obtained by the conventional melt growth process.

• Journal of Welding and Joining
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• 제6권4호
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• pp.16-26
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• 1988

The effect of carbon content on hot cracking of welded carbon steel was investigated Eight steel plates whose carbon content range from 0.02 to 0.23 percent were welded by autogeous gas tungsten are process. Constant strain was applied to the hot crack test specimen under the strain rate of 0.15 mm per second during welding. The hot cracking susceptibility ws high in the rnage of 0.02-0.05 and 0.12-0.23 percent carbon contents. The critical carbon content immune to hot cracking is in the range from 0.07 to 0.12 percent carbon. By electron probe microanalyser, amanganese segregation was not seen significantly in the whole carbon range. But segregation of silicon was higher in the region of low carbon contents. However, sulphur was segregated remarkably in the region betwen 0.18 and 0.23 percent carbon by peritectic reaction. Very smal lamount of dnedritic structure was observed in the region from 0.02 to 0.05 percent carbon by peritectic reaction. Very small amount of dendritic structure was observed in the region from 0.02 to 0.05 percent carbon but the predominant solidification structure was smooth by cellular growth. The higher the carbon content is, the more the columnar dendritic structure was observed.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2010년도 임시총회 및 하계학술연구발표회
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• pp.165-166
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• 2010

• 자원리싸이클링
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• 제30권4호
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• pp.20-26
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• 2021

태양전지용 실리콘은 주로 반도체급 실리콘 제조공정에서 발생하는 규격외 실리콘을 사용하여 왔다. 태양전지의 보급 활성화를 위해서는 보다 저렴한 정제 공정의 개발이 필요하다. 태양전지용 실리콘을 위한 저비용이면서 효율적인 방법은 금속급 실리콘을 정제하여 고순도화하는 것이다. 본 연구에서는 금속급 용융 실리콘 중의 Fe를 제거하기 위해 고주파 유도로 중에서 일방향 응고를 실시하였다. 실험조건과 실험결과를 유효 편석계수, Scheil 식 및 Peclet 수로 평가하였다. 시료의 하강속도가 감소함에 따라 불순물의 매크로 편석과 잉곳의 순도가 증가하였다. 이러한 결과는 시료의 하강속도 감소에 따른 유효 편석계수의 감소에 의한 것으로 생각된다.

• KIEE International Transactions on Electrophysics and Applications
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• 제5C권1호
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• pp.18-22
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• 2005

We developed a new systematic calibration procedure and applied it to the calibration of the diffusivity, segregation and TED model of the indium impurity. The TED of the indium impurity was studied under 4 different experimental conditions. Although the indium proved to be susceptible to the TED, the RTA was effective in suppressing the TED effect and in maintaining a steep retrograde profile. Just as in the case of boron, indium demonstrated significant oxidation-enhanced diffusion in silicon and its segregation coefficients at the Si/SiO₂ interface were significantly below 1. In contrast, the segregation coefficient of indium decreased as the temperature increased. The accuracy of the proposed technique has been validated by SIMS data and 0.13-㎛ device characteristics such as Vth and Idsat with errors less than 5% between simulation and experiment.

• Transactions on Electrical and Electronic Materials
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• 제5권6호
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• pp.211-214
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• 2004

We developed a new systematic calibration procedure which was applied to the calibration of the diffusivity, segregation and TED model of the indium impurity. The TED of the indium impurity has been studied using 4 different groups of experimental conditions. Although the indium is susceptible to the TED, the RTA is effective to suppress the TED effect and maintain a steep retrograde profile. Like the boron, the indium shows significant oxidationenhanced diffusion in silicon and has segregation coefficients at the $Si/SiO_2$ interface much less than 1. In contrast, however, the segregation coefficient of indium decreases as the temperature increases. The accuracy of the proposed technique is validated by SIMS data and $0.13 {\mu}m$ device characteristics such as $V_{th}$ and $Id_{sat}$ with errors less than $5 \%$ between simulation and experiment.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2003년도 추계학술대회 발표 논문집
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• pp.31-34
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• 2003

We developed a new systematic calibration procedure which was applied to the calibration of the diffusivity, segregation and TED model of the indium impurity. The TED of the indium impurity has been studied using 4 different groups of experimental conditions. Although the indium is susceptible to the TED, the RTA is effective to suppress the TED effect and maintain a steep retrograde profile. Like the boron, the indium shows significant oxidation-enhanced diffusion in silicon and has segregation coefficients at the $Si/SiO_2$ interface much less than 1. In contrast, however, the segregation coefficient of indium decreases as the temperature increases. The accuracy of the proposed technique is validated by SIMS data with errors less than 5% between simulation and experiment.