Influence of Bi Addition on Pure Sn Solder Joints: Interfacial Reaction, Growth Behavior and Thermal Behavior  

作　　者：LAI Yanqing HU Xiaowu 赖彦青;胡小武;LI Yulong;JIANG Xiongxin(Key Lab for Robot & Welding Automation of Jiangxi Province,Mechanical & Electrical Engineering School,Nanchang University)

机构地区：[1]Key Lab for Robot & Welding Automation of Jiangxi Province,Mechanical & Electrical Engineering School,Nanchang University

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2019年第3期668-675,共8页武汉理工大学学报（材料科学英文版）

基　　金：Funded by the National Natural Science Foundation of China(No.51465039);Natural Science Foundation of Jiangxi Province(No.20151BAB206041,20161BAB206122);Fund of the State Key Laboratory of Solidification Processing in NWPU(No.SKLSP201508)

摘　　要：The effects of different Bi contents on the properties of Sn solders were studied. The interfacial reaction and growth behavior of intermetallic compounds（IMCs） layer（η-Cu6 Sn5 + e-Cu3 Sn） for various soldering time and the influence of Bi addition on the thermal behavior of Sn-x Bi solder alloys were investigated. The Cu6 Sn5 IMC could be observed as long as the molten solder contacted with the Cu substrate. However, with the longer welding time such as 60 and 300 s, the Cu3 Sn IMC was formed at the interface between Cu6 Sn5 and Cu substrate. With the increase of soldering time, the thickness of total IMCs increased, meanwhile, the grain size of Cu6 Sn5 also increased. An appropriate amount of Bi element was beneficial for the growth of total IMCs,but excessive Bi（≥ 5 wt%） inhibited the growth of Cu6 Sn5 and Cu3 Sn IMC in Sn-x Bi/Cu microelectronic interconnects. Furthermore, with the Bi contents increasing（Sn-10 Bi solder in this present investigation）, some Bi particles accumulated at the interface between Cu6 Sn5 layer and the solder.The effects of different Bi contents on the properties of Sn solders were studied. The interfacial reaction and growth behavior of intermetallic compounds (IMCs) layer(7/-Cu6Sn5 + e-Cu3Sn) for various soldering time and the influence of Bi addition on the thermal behavior of Sn-xBi solder alloys were investigated. The Cu6Sn5 IMC could be observed as long as the molten solder contacted with the Cu substrate. However, with the longer welding time such as 60 and 300 s, the Cu3Sn IMC was formed at the interface between Cu6Sn5 and Cu substrate. With the increase of soldering time, the thickness of total IMCs increased, meanwhile, the grain size of Cu6Sn5 also increased. An appropriate amount of Bi element was beneficial for the growth of total IMCs, but excessive Bi (≥ 5 wt%) inhibited the growth of Cu6Sn5 and Cu3Sn IMC in Sn-xBi/ Cu microelectronic interconnects. Furthermore, with the Bi contents increasing (Sn-l0Bi solder in this present investigation), some Bi particles accumulated at the interface between Cu6Sn5 layer and the solder.

关 键 词：INTERMETALLIC compound Sn-xBi SOLDER joints INTERFACIAL reaction thermal BEHAVIOR 

分 类 号：TB[一般工业技术]