The study on the interaction of interfacial reactions between UBM/solder and solder/pad in miniature joints
This study investigated the interaction of interfacial reactions between Cu/Sn3.5Ag and Sn3.5Ag/AuNi diffusion couples with different stand-off heights (SOH) in miniature solder joints. After reflowing, many (Cux,Ni1-x)6Sn5 IMCs were found to surround the original IMCs at both interfaces of the solder joint, which were attributed to Cu and Ni atoms diffusion throughout the whole solder. This phenomenon was defined as the interaction of two interfacial reactions in miniature solder joints. The concentrations of Ni and Cu in (Cux,Ni1-x)6Sn5 ternary IMC at each side depended on the diffusion rates to Ni and Sn, the height of the solder joint and the experimental conditions. At Sn3.5Ag/AuNi interface, the concentrations of Ni and Cu decreased and increased in (Cux,Ni1-x)6Sn5 ternary IMCs with SOH decreasing,respectively. At Cu/Sn3.5Ag interface, the concentrations of Ni and Cu changed in opposite rules. Cu had a faster diffusion rate in molten Sn to generate a higher concentration in(Cux,Ni1-x)6Sn5, which also took a sharp slope of the percentage of IMC thickness/SOH with SOH increasing at Sn3.5Ag/AuNi interface.
Hui Liu Fengshun Wu Mingmin He Jinsong Zhang Yang Yu Yiping Wu Bing An
State Key Laboratory of Material Processing and Die & Mould Technology, Huazhong University of Scien State Key Laboratory of Material Processing and Die & Mould Technology, Huazhong University of Scien
国际会议
第八届电子封装技术国际会议(2007 8th International Conference on Electronics Packaging Technology ICEPT2007)
上海
英文
632-635
2007-08-14（万方平台首次上网日期，不代表论文的发表时间）