• 한국전기전자재료학회논문지
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• 제37권1호
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• pp.74-78
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• 2024

We have studied the effects of Ag on the characteristics of Sn₄₈In₅₂Ag_x (wt%) low-melting solders for photovoltaic ribbons. The Sn₄₈In₅₂ (wt%) solder coexisted in the InSn₄ and In₃Sn alloys. Ag atoms added in the solder formed an AgIn₂ alloy by reacting with some part of In atoms, while they did not react with Sn atoms. The addition of Ag atoms in the Sn₄₈In₅₂Ag_x (wt%) solders showed useful results; an increase in peel strength and a decrease in melting temperature. The peel strength of the ribbon plated with the Sn₄₈In₅₂ (wt%) solder was 53.6 N/mm², and that of the Sn₄₈In₅₂Ag₁ (wt%) solder largely increased to 125.1 N/mm². In the meanwhile, the melting temperature of the Sn₄₈In₅₂ (wt%) solder was 119.2℃, and that of the Sn₄₈In₅₂Ag₁ (wt%) solder decreased to 114.0℃.

• 마이크로전자및패키징학회지
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• 제12권4호통권37호
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• pp.351-357
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• 2005

솔더/UBM 계면반응에 따른 솔더범프의 기계적 신뢰성을 평가하기 위한 방안으로서 Cu UBM 상에서 리플로우한 Sn-52In 솔더범프의 리플로우 조건에 따른 전단응력과 전단에너지의 변화거동을 비교하였다. 리플로우 조건에 따른 전단에너지의 변화거동이 전단강도에 비해 Sn-52In/Cu 계면반응 및 파괴모드의 변화거동과 훨씬 잘 일치하여 솔더/UBM 계면반응에 따른 기계적 신뢰성을 분석하는데 전단에너지가 전단강도보다 훨씬 효과적인 평가 방안임을 알 수 있었다.

• 마이크로전자및패키징학회지
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• 제12권1호
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• pp.87-93
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• 2005

Au 층의 두께를 $0.1{\~}0.7{\mu}m$로 변화시킨 $0.1{\mu}m$ Ti/3 ${\mu}m$ Cu/Au UBM 상에서 48Sn-52In 솔더를 $150-250^{\circ}C$의 온도 범위에서 리플로우시 UBM/솔더 반응에 의한 금속간화합물의 형성거동을 분석하였다. 또한 Ti/Cu/Au UBM의 Au 두께 및 리플로우 온도에 따른 볼 전단강도와 전단에너지를 분석하였다. $150^{\circ}C$와 $200^{\circ}C$에서 리플로우 시에는 UBM/솔더 계면에 $Cu_6(Sn,In)_5$와 $AuIn_2$ 금속간 화합물이 형성되어 있으나, $250^{\circ}C$에서 리플로우 시에는 솔더 반응이 크게 증가하여 UBM이 대부분 소모되었다. 볼 전단강도는 UBM/솔더 반응과 일치하지 않는 결과를 나타내었으나, 전단 에너지는 UBM/솔더 반응과 잘 일치하는 변화 거동을 나타내었다.

• 한국전기전자재료학회논문지
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• 제36권2호
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• pp.186-190
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• 2023

We studied the various characteristics of Sn-In (wt%) Pb-free solders for photovoltaic ribbon application. The solders near the eutectic composition of Sn₄₈In₅₂ (wt%) existed in InSn₄ and In₃Sn alloy phases, and in In crystal phase, but not in Sn crystal phase. In addition, the InSn₄ phase (γ-alloy) existed separately from the In₃Sn (β-alloy) and the In phase confirmed by an SEM-EDS-mapping. The melting temperature of the eutectic solder of Sn₄₈In₅₂ (wt%) was 119.2℃, and when the Sn content decreased in reference to the eutectic composition, it slightly increased to 121.4℃, but when the Sn content increased, it remained almost constant at 119.1℃. The peel strength of the ribbon plated with the Sn₄₂In₅₈ (wt%) solder was 38.7 N/mm², and it tended to increase when the Sn content increased. The peel strength of the eutectic Sn₄₈In₅₂ (wt%) solder was 53.6 N/mm², and that of the Sn₅₁In₄₉ (wt%) solder was 61.6 N/mm² that was the highest.

• 마이크로전자및패키징학회지
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• 제9권2호
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• pp.39-43
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• 2002

48 $\mu$BGA 패키지에 Sn-37Pb 공정 솔더와 Sn-0.7Cu, Sn-3.5 Ag, Sn-2.0Ag-0.75Cu, Sn-2.0Ag-0.7Cu-3.0Bi 4종류의 무연 솔더를 적용하여, 미세 솔더 볼의 경도와 조성에 따른 솔더 접합부의 전단강도에 대해서 연구하였다. 실험 결과, 솔더 볼의 짖눌림은 Sn-2.0Ag-0.7Cu-3.0Bi에서 0.043mm로 큰 경도값을 얻었다. 또한 전단 강도 값은 무연 솔더가 Sn-37Pb 솔더보다 높았으며, Sn-2.0Ag-0.7Cu-3.0 Bi에서 최대 52% 높은 값을 나타내었다.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2003년도 기술심포지움 논문집
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• pp.99-102
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• 2003

Reactions between 48Sn-52In solder and under bump metallurgies(UBM) such as 100nm $Ti/8{\mu}m$ Cu and 300nm Al/400nm Ni(V)/400nm Cu have been investigated, and the shear strength of 48Sn-52In solder bumps on each UBM has been evaluated. While intermetallic compounds with two different morphologies were continuously thickened on Ti/Cu with repeating the reflow process, the intermetallics on Al/Ni(V)/Cu spalled into the solder with increasing the number of reflow times. The solder bumps on Ti/Cu exhibited higher shear strength than those on Al/Ni(V)/Cu.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1995년도 특별강연 및 추계학술발표 개요집
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• pp.110-112
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• 1995

Initial solder joint strengths of various solder pastes, such as Sn-Pb(63-37wt%), Sn-In(52-48wt%), Sn-In-Ag(77.5-20-2.5wt%), and Sn-Ag(96.5-3.5wt%) has been studied. A system that can control the solder joint interface temperature during bonding process was also desined and implemented to improve solder joint integrity.

• Journal of Welding and Joining
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• 제15권2호
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• pp.36-42
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• 1997

In this paper, stability of initial strength at solder joint with lead free solders, such as Sn-In (52-48%) and Sn-Ag (96.5-3.5wt%) was studied. To obtain at solder joint with high quality, it is very important to control the temperature at the interface of solder joints. It is found that the thermal EMF (electro motive force) occurs betwee lead frame and copper pad on a substrate during reflow soldering process using heated tip. As a result of control the temperature at interface of solder joints, variation of initial strength at solder joint decreases from about $\pm40%$ to $\pm20%$, and it is realized Pb free soldering process using Sn/In and Sn-Ag solder paste.

• Journal of Welding and Joining
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• 제16권5호
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• pp.100-107
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• 1998

This paper describes fluxless soldering of reflow soldering process using solder foil instead of solder pastes. There is an increasing demand for the reliable solder connection in the recent high density microelectronic components technologies. And also, it is problem fracture of an Ozone layer due to freon as which is used to removal of remained flux on the substrate. This paper discussed joining phenomena, boudability and joining processes of microelectronics devices, such as between outer lead of VLSI package and copper pad on a substrate without flux. The shear strength of joints is 8 to 13 N using Sn/Pb (63/37 wt.%) solder foil with optimum joining conditions, meanwhile, in case of using Sn/In (52/48 wt.%) solder foil, it is possible to bond with low heating temperature of 550 K, and accomplish to high bonding strength of 25N in condition heating temperature of 650K. Finally, this paper experimentally shows fluxless soldering using solder foil, and accomplishes key technology of microsoldering processes.

• 한국식품저장유통학회지
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• 제17권3호
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• pp.376-383
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• 2010

견과류 중 sunflower seed, cashew nut, walnut, pistachio, pumpkin seed, ginkgo, hazel nut, pecan을 원료로 하여 지방산 조성 분석 및 sn-2 position 분석, triacylglycerol species의 분석, tocopherol, phytosterol 함량을 분석하였다. 조지방 함량은 hazel nut에서 약 39.60 wt%로 가장 높았으며, walnut 35.25 wt%, pistachio 30.22 wt% 등의 순이었다. GC에 의한 sn-2 위치의 지방산 조성 분석 결과, oleic acid의 함량이 많은 견과류는 cashew nut, pistachio, hazel nut, pecan 이였으며, 특히 ginkgo의 경우 특이적으로 oleic acid의 이성체인 vaccenic acid가 10.72 wt% 나타냄을 확인할 수 있었다. 반면, linoleic acid 등이 높은 견과류는 sunflower seed, walnut, pumpkin seed 이었다. 견과류들의 TAG species의 PN값은 40∼52 사이에 존재하였다. Tocopherol의 함량은 ginkgo, sunflower seed, pumpkin seed 등에서 각각 48.57, 38.35, 31.43 mg/100 g 순으로 높은 함량을 나타내었다. 또한 총 phytosterol의 경우 88.60∼947.20 mg/100 g 사이에 함량을 나타내었다.