摘要
为提高塑料球栅阵列(PBGA)器件焊点可靠性,提出了一种基于田口法和数值模拟的试验方法.借用Anand模型描述钎料本构方程,对PBGA器件焊点热循环载荷下的应力应变分布进行有限元模拟.结果表明,填充底充胶能有效提高焊点可靠性;考虑基板、封装塑料、底充胶、PCB的线膨胀系数四个控制因素,借助田口试验法进行最佳参数选择,确定影响焊点可靠性的主要因素为基板线膨胀系数及封装塑料线膨胀系数.最优方案组合为A3B3C3D3.该优化方案的最大等效应变比原始值减小了41.4%,信噪比提高了4.61 dB.
In order to evaluate the reliability of PBGA soldered joints,an optimized method was proposed based on Taguchi design and numerical simulation,in which the Anand equation was used to describe the viscoplastic behavior of Sn3.0Ag0.5Cu solder,and the distribution of equivalent stress and strain in soldered joints under temperature cycle were studied respectively.Results indicate that the thermal fatigue life of soldered joints can be substantially improved by filling up the underfill between the PCB and substrate.The linear expansion coefficients of substrate,epoxy mold compound,underfill and PCB were considered as the controlling factors,and the linear expansion coefficient of the substrate and that of epoxy mold compound were deemed to the main influencing factors by Taguchi method.The optimized controlling factor combination can be decided as A3B3C3D3,and the verification test shows the maximum equivalent strain of the optimization scheme was decreased by 41.4%,and the ratio of signal to noise was increased by 4.61 dB.
出处
《焊接学报》
EI
CAS
CSCD
北大核心
2009年第11期81-84,共4页
Transactions of The China Welding Institution
基金
2006年江苏省"六大人才高峰"基金资助项目(06-E-020)
2009年江苏省普通高校研究生科研创新计划资助项目(BCXJ0907)
关键词
塑料球栅阵列
底充胶
田口法
线膨胀系数
plastic ball grid array
underfill
Taguchi method
linear expansion coefficient
