【摘要】 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。更多还原

【Abstract】 The method of drop-free was used to study the reliability of BGA(ball grid array) package flip solder joints under drop-free impact on different contact surfaces.The mechanics of crack appearance,extension and fracture in solder joints were analyzed.The failure position and morphologies in solder joints were observed through dyeing method.The results show that all of cracks experience steady state-extension-failure process on different contact surfaces.The test results appear the earliest,extending and failing the fastest cracks on the rocky surface,the steel surface takes the second place,the last one is the woodiness surface.The solder joint failure mode on woodiness surface is bonding pad failure.However,there are intermetallic compound failure on steel surface and rocky surface.The life evaluated from PHM model has small error compared with the result from experiences,which can predict the life of solder joint under drop-free impact effectively.更多还原