多场耦合载荷下微焊点的疲劳寿命分析  

Analysis of Fatigue Life for Micro-Scale Solder Joint Under Multi-Field Coupling Loads

作　　者：朱桂兵[1,2] 杨智然 孙蕾 Zhu Guibing;Yang Zhiran;Sun Lei(School of Intelligent Manufacturing,Nanjing Vocational College of Information Technology,Nanjing 210046,China;School of Physics,Material ScienceAnhui Ufiiversity,Hefei 213001,China;Department of Mechanical,Hong Kong University of Science and Technology,Hong Kong 999000,China)

机构地区：[1]南京信息职业技术学院智能制造学院,南京210046 [2]安徽大学物理与材料学院,合肥213001 [3]香港科技大学机械工程系,香港999000

出　　处：《微纳电子技术》2021年第12期1077-1082,共6页Micronanoelectronic Technology

基　　金：国家自然科学基金资助项目(51502001);南京信息职业技术学院中青年学术带头人项目(NJICTQL20200102);江苏省“青蓝工程”资助项目(JSQL2017-06)。

摘　　要：选择Sn_(96.5)Ag_(3.0)Cu_(0.5)(SAC305)和Sn_(63)Pb_(37)(Sn-37Pb)两种焊料制成焊膏和焊球,印制电路板(PCB)焊盘采用Ni/Au化学电镀处理,以芯片尺寸封装(CSP)和方形扁平无引脚(QFN)封装两种器件为研究载体,设计一种为芯片持续提供电载荷和恒温的测试夹具并将其置于热循环和跌落耦合冲击实验中,研究该多场耦合环境对微焊点疲劳寿命的影响。结果表明在持续电载荷和恒温环境下,在Ni/Au处理的焊盘上,微焊点的抗跌落冲击寿命的下降速度是先快后慢;焊点受到低于100周的热循环冲击时,它的抗跌落冲击寿命的下降速度约为1.3次/周,高于100周后的下降速度逐渐降低至约0.05次/周;与非持续多场载荷作用下焊点相比,它的寿命下降约40%。在低周热循环和低能级跌落耦合冲击条件下,无铅和有铅焊点的抗跌落冲击寿命相当,在高周热循环和高能级跌落耦合冲击条件下,无铅焊点具有更高的抗跌落冲击寿命。The solder materials of Sn_(96.5)Ag_(3.0)Cu_(0.5)(SAC305) and Sn_(63)Pb_(37)(Sn-37 Pb) were used to prepare solder paste and solder ball, and printed circuit board(PCB) pads were treated by Ni/Au chemical plating. The two kinds of devices with chip size package(CSP) and quad flat no-leads(QFN) package were used as the research substrates, a testing fixture was designed to supply continuous electric load and constant temperature for the chips, and was subjected to thermal cycle and drop coupled shock experiment to study the effect of the multi-field coupling environment on fatigue life of micro-scale solder joint. The results show that under sustained electrical load and constant temperature, the descent velocity of anti-drop shock life of the micro-scale solder joint on Ni/Au treated pads is fast first and then slow. The descent velocity of anti-drop shock life for solder joint is about 1.3 times/cycle when the solder joint is subjected to thermal cycle shock of less than 100 cycles, and the descent velocity gradually decreases to about 0.05 times/cycle under thermal cycle shock of more than 100 cycles. Compared to the solder joint under non-sustained multi-field loads, its life is reduced by about 40%. The lead-free solder joint has equitable anti-drop shock life with the lead solder joint under the coupled shock condition of low circum-thermal cycle and low-level drop. The lead-free solder joint has the higher anti-drop shock life than lead solder joint under the coupled shock condition of high circum-thermal cycle and high-level drop.

关 键 词：微焊点 电热力耦合 芯片尺寸封装(CSP) 缺陷生长 无铅焊点 

分 类 号：TN305.94[电子电信—物理电子学]