• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1510-1512
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• 2000

Due to the shrinking of the chip size and increasing of the complexity in the modern electronic devices. the defect of wafer are so important to decide the yield in the device process. The engineers has studied the wafer defects and the characteristics. They published lots of the experimental methods. I did an experiment the gettering effect of the defects due to the high temperature and the long time diffusion. Actually, As the thickness of the wafer backside polysilicon is thicker and the diffusion time is faster. the defects on the wafer are decreased. The polysilicon gram boundaries of the wafer backside played an important part as the defect gettering site.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2003년도 춘계학술발표대회 요약집
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• pp.335.2-335.2
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• 2003

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.37-40
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• 2001

This paper presents the modeling methodology of Zinc diffusion process applied for high-speed avalanche photodiode fabrication using neural networks. Three process factors (sealing pressure, amount of Zn$_3$P$_2$ source per volume, and doping concentration of diffused layer) are examined by means of D-optimal design experiment. Then, diffusion rate and doping concentration of Zinc in diffused layer are characterized by a static response model generated by training fred-forward error back-propagation neural networks. It is observed that the process models developed here exhibit good agreement with experimental results.

• 대한수학회논문집
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• 제14권4호
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• pp.815-832
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• 1999

High-order weighted difference schemes with uniform meshes are considered for the convection-diffusion problem depending on Reynolds numbers. For small Reynolds numbers, a weighed cen-tral difference scheme is suggested since there is no boundary layer. For large Reynolds numbers, we propose a modified up wind method with an artificial diffusion in order to overcome nonphysical oscilla-tion of central schemes and obtain good accuracy in the boundary later. Existence and corresponding error estimates of the solution for the difference scheme have been shown. Numerical experiments are provided to back up the analysis.

• 한국전기전자재료학회논문지
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• 제20권2호
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• pp.106-112
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• 2007

Advanced back-end processing requires the integration of low-k dielectrics and Cu. However, in the presence of an electric field and a temperature, positive Cu ions may drift rapidly through dielectric and causing reliability problems. Therefore, in this paper, Cu+ drift diffusion in two low-k materials and silicon oxide is evaluated. The drift diffusion is investigated by measuring shifts in the flat band voltage of capacitance-voltage measurements on Cu gate capacitors after bias thermal stressing. The Cu+ drift late in $SiO_{x}C_{y}\;(2.85{\pm}0.03)$ and Polyimide(2.7${\leq}k{\leq}3.0$) is Considerably lower than in thermal oxide.

• 대한전자공학회논문지
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• 제20권1호
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• pp.22-26
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• 1983

열확산(thermal diffusion)법을 이용하여 면적이 3.36㎠인 P+N 전지와 P+NN+ 전지를 제작하였다. 100mW/㎠의 인공 조명에서 측정한 결과 940℃에서 15분 보론확산(boron Predeposition)을 하고, 800℃에서 20분 열처리(annealing)하여 제작한 P+N전지는 전면적(수광면적) 변환 효율이 13.4%(14.7%)이었다. 뒷면을 1050℃에서 인(Phosphorus)을 확산한 후, 앞면을 940℃에서 15분 보론 확산하고, 800℃에서 50분 열처리하여 만든 P+NN+전지의 전면적(수광면적) 변환 효율은 14.3%(15.6%)이었다. 뒷면의 인 확산으로 게더링(gettering) 작용과 BSF 효과에 의해서 P+NN+ 전지가 P+N전지보다 캐리어 수명이 약 2∼3배 증가되었다. 그리고 효율 개선을 위해 AR로팅, Ag전기도금, 미세한 그리드 패턴, 앞면 불순물 주입량 조절 등을 행하였다.

• Corrosion Science and Technology
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• 제18권6호
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• pp.267-276
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• 2019

The purpose of this study was to examine the influence of conditions for quenching and/or tempering on the corrosion and hydrogen diffusion behavior of ultra-strong automotive steel in terms of the localized plastic strain related to the dislocation density, and the precipitation of iron carbide. In this study, a range of analytical and experimental methods were deployed, such as field emission-scanning electron microscopy, electron back scatter diffraction, electrochemical permeation technique, slow-strain rate test (SSRT), and electrochemical polarization test. The results showed that the hydrogen diffusion parameters involving the diffusion kinetics and hydrogen solubility, obtained from the permeation experiment, could not be directly indicative of the resistance to hydrogen embrittlement (HE) occurring under the condition with low hydrogen concentration. The SSRT results showed that the partitioning process, leading to decrease in localized plastic strain and dislocation density in the sample, results in a high resistance to HE-induced by aqueous corrosion. Conversely, coarse iron carbide, precipitated during heat treatment, weakened the long-term corrosion resistance. This can also be a controlling factor for the development of ultra-strong steel with superior corrosion and HE resistance.

• 한국연소학회지
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• 제15권3호
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• pp.74-81
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• 2010

In this study, soot formation characteristics on the instability of laminar diffusion flames were investigated experimentally using a concentric co-flow burner. When a small amount of air was supplied through an inner nozzle, a stable propane laminar diffusion flame became unstable and began to oscillate mainly due to the dilution effect. The increase of air flow rate transformed an oscillating non-sooting flame into a stable nonsooting flame. When the air flow rate was continuously increased an inner flame was formed and the flame was changed to an oscillating sooting flame, an oscillating non-sooting flame and finally a stable non-sooting hollow flame. When the air flow rate was decreased, a non-sooting hollow flame was eventually changed back to a stable non-sooting flame. The presence of an inner flame, however, altered the soot formation characteristics of a flame. More soot production was observed with the presence of an inner flame. The increased or decreased soot formation/oxidation rates, the radiation heat loss, and the heating effect of inner flames are most likely to be responsible for the observed instability of laminar diffusion flames.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.40-44
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• 2011

Recent studies in crystalline silicon solar cell fabrication have been focused on high efficiency and low cost. However, the rising of the cost results in additional processes to approach high efficiency. The fabrication process also becomes complicated with additional technologies. In this paper, we studied the selective emitter formation with phosphorous paste to improve the conversion efficiency. Selective emitter formations like two-step diffusion or etch-back method require at least one more step compared in the conventional line since heavily and lightly doped area was needed to form separately.However,one-step diffusion process is the method diffusing heavily and lightly doped area at the same time only with additional screen-printing step. This study lays the foundation for the simple way to form the selective emitter.

• 한국토양비료학회지
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• 제28권3호
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• pp.233-240
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• 1995

Ficks의 확산 편미방을 Laplace 변환을 적용하여 초기 및 경계조건과 함께 종속 대수 함수로 변환하고 Burington의 역변환표를 활용하여 복귀하는 방법으로 Ficks의 확산 편미방의 해를 구하였다. 적용된 초기 및 정계조건은 일정깊이의 담수에로 무한 깊이의 일정 염농도의 균일한 간척지 토양에서 상향 염분확산 이동에 대한 것이었다. 유도된 해는 특이 조건에서의 비교법으로 오.등 및 Kirkham, 등이 보고 한 간단한 초기 빛 경계조건에서의 해와 일치함을 확인했다. Ficks의 확산식의 해로 계산된 완만한 제염 속도를 근거로하여 담수 제염 방법별 제염 속도와 토양중 염분분포를 추정할수있는 모형식을 제시하였다.