Numerical Study on the Effects of Bond Parameters on Thermosonic Bond Strength
Thermosonic ball bonding is a popular joining technique in microelectronic interconnect. In this paper, the effects of bonding parameters on the bond strength are investigated mainly using the finite element method. The complete ball bonding process including both the impact and ultrasonic vibration stages is modeled, and the strain rate sensitivity of the gold ball and pad is considered. Five variables were defined to establish the relationship between bonding interfacial deformation and bond strength: the segment extension εi, the ratio of segment extension ki, the contact ratio S, the sum of segment extensions in bond interface Σεi and the ratio of the sum of segment extensions k.It was found that the bond strength at the bond interface increases from the center to edge; the bond strength increases with the growth of the initial impact velocity; the bond strength increases firstly with the increasing of the bonding time, then decreases; and there exists an appropriate temperature to let the bond strength to be maximum. Finally,the simulation is compared with the experimental results.
Jun He Yongjin Guo Zhongqin Lin
School of Mechanical Engineering, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, PR China
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
601-612
2007-08-14（万方平台首次上网日期，不代表论文的发表时间）