论文部分内容阅读
采用自由跌落的试验方法,研究了BGA(球栅阵列)封装自由跌落到不同材质基板后的可靠性,对比分析焊点裂纹产生、扩展直至断裂的机理。对失效封装芯片进行了染色处理,观察BGA封装中焊点的失效位置和焊点内部裂纹的形貌。结果表明,不同接触面上焊球裂纹都经历稳态-扩展-失效的过程,石质接触面上裂纹出现最早,裂纹扩展最快,失效最快,钢质接触面次之,最后是木质接触面。木质接触面的焊点失效模式主要是焊盘失效;钢质和石质接触面的焊点的失效模式以金属间化合物失效为主。比例风险模型(PHM)估计得到的寿命值与试验结果误差较小,能有效预测焊点自由跌落条件下的寿命。
The free fall test method was used to study the reliability of BGA packages dropping freely to different substrates. The mechanism of crack growth and fracture was compared and analyzed. The failure of packaged chips were dyed to observe the failure location of BGA package solder joints and cracks in the shape of the internal solder joints. The results show that the solder ball cracks on different contact surfaces all undergo steady-state-expansion-failure process. The cracks on the stone contact surface are the earliest, the crack propagation is the fastest, the failure is the fastest, the steel contact surface is the second, and finally the wood contact surface. The failure modes of the solder joints on the wood contact surface are mainly the failure of the solder pads. The failure modes of the solder joints on the steel and stone contact surfaces are dominated by the failure of the intermetallic compounds. The lifetime error of the proportional hazards model (PHM) is less than that of the experimental results, which can effectively predict the life expectancy under free fall of solder joints.