温度冲击下多器件组装PCB板热应力及寿命分析  

Thermal Stress and Life Analysis of Multi-device Assembly PCB Board Under Temperature Shock

作　　者：梁东成 陈东东[1,2] 张欣 秦俊虎 卢红波 严继康 易健宏[1] LIANG Dongcheng;CHEN Dongdong;ZHANG Xin;QIN Junhu;LU Hongbo;YAN Jikang;YI Jianhong(Faculty of Material Science and Engineering,Kunming University of Science and Technology,Kunming 650093,China;Yunnan Tin Industry Tin Material Co.,Ltd.,Kunming 650501,China;School of Engineering,Southwest Petroleum University,Nanchong 637001,China)

机构地区：[1]昆明理工大学材料科学与工程学院,昆明650093 [2]云南锡业锡材有限公司,昆明650501 [3]西南石油大学工程学院,四川南充637001

出　　处：《有色金属工程》2022年第2期14-23,共10页Nonferrous Metals Engineering

摘　　要：微电子封装元器件在恶劣环境或特定条件下持续稳定工作的能力(可靠性)受到了越来越多的关注,对可靠性提出了更高的要求。基于ANSYS有限元平台研究了多器件组装PCB(印制电路板)在温度冲击下不同元器件服役状态,对不同尺寸元器件焊点进行建模,通过网格划分,加载温度载荷曲线,分析在回流焊、温度冲击下残余应力、应变分布情况,并通过Coffin-Masson寿命公式预测了SAC3807钎料在温度冲击下的疲劳寿命。结果表明,PBGA(塑料焊球阵列封装)在温度冲击载荷下,边角最外侧焊点应力值最高,主要是由于高升降温速率下热应力集中。对于QFP(方型扁平式封装)与SOP(小外形封装)形式,钎料与引脚连接处最易发生裂纹萌生,且在引脚间距相同情况下,多引脚封装具有更高可靠性。多器件组装PCB板焊点在温度热冲击载荷下焊点的疲劳寿命低于温度热循环载荷下的疲劳寿命。More and more attention has been paid to the ability(reliability)of microelectronic package components to work continuously and stably under harsh environment or specific conditions,and higher requirements have been put forward for reliability.Based on ANSYS finite element platform,the service states of different components of multi-device PCB(printed circuit board)under temperature shock were studied.The components of different sizes and solder joints were modeled.The distribution of residual stress and strain under reflow soldering and temperature shock was analyzed through grid division and temperature load curve loading.The fatigue life of SAC3807 solder under temperature impact is predicted by Coffin-Masson life formula.The results show that the stress of PBGA(plastic ball grid array)is the highest in the outmost solder joint under temperature impact.It is mainly due to the concentration of thermal stress at high lift and cooling rates.For QFP(guad flat package)and SOP(small outline package),the joint between solder and pin is the most prone to crack initiation,and the multi-pin package has higher reliability when the pin spacing is the same.The fatigue life of solder joints under thermal shock load is lower than that under thermal cycle load.

关 键 词：多器件组装 温度冲击 热应力 寿命分析 

分 类 号：TG4[金属学及工艺—焊接]