基于COMSOL的Cu@Sn@Ag焊片真空瞬态液相扩散焊仿真研究  

Simulation study of Cu@Sn@Ag welding element based on COMSOL vacuum transient liquid phase diffusion welding

作　　者：吴艳 欧阳佩旋 徐红艳[2] 张淑婷 董智超 WU Yan;OU YANG Peixuan;XU Hongyan;ZHANG Shuting;DONG Zhichao(School of Mechanical and Materials Engineering,North China University of Technology,Beijing 100144,China;Institute of Electrical Engineering,Chinese Academy of Sciences,Beijing 100190,China)

机构地区：[1]北方工业大学机械与材料工程学院,北京100144 [2]中国科学院电工研究所,北京100190

出　　处：《焊接技术》2023年第2期71-76,I0008,共7页Welding Technology

摘　　要：在电力电子封装时,瞬态液相扩散焊过程中焊料层的应力分布是影响器件服役性能和使用寿命的重要因素。文中基于SiC芯片瞬态液相扩散焊的工况,利用有限元仿真软件COMSOL建立了Cu@Sn@Ag焊片用于回流焊接SIC芯片与DBC板的三维有限元模型,针对瞬态液相扩散焊,结合弹塑性变形等相关理论,系统研究了瞬态液相扩散焊的焊接工艺温度、焊接时间及焊接保压压力对Cu@Sn@Ag焊层应力分布及大小的影响。研究结果表明:焊接温度在240~260℃时,随着焊接温度的升高,焊后焊层峰值应力逐渐减小;当焊接温度处于260~280℃时,又略有升高,在260℃时应力最小;焊接保温时间在30~90 min时,随着焊接保温时间的延长,焊层的应力保持不变,90 min以上时焊层处的应力开始升高;当焊接保压压力为1~5 MPa时,随着保压压力的增大,焊层处的应力也初步增大。综合考虑器件服役性能的需求,Cu@Sn@Ag焊片用于回流焊接SiC芯片和DBC板,焊接温度以260℃为宜,焊接保温时间以30 min为宜,焊接保压压力以1 MPa为宜。In power electronics packaging,the stress distribution of the solder layer during transient liquid phase diffusion welding was an important factor affecting the service performance and service life of the device.Based on the working conditions of transient liquid phase diffusion welding of Si C chip,the finite element simulation software COMSOL was used to establish a three-dimensional finite element model of Cu@Sn@Ag solder blade for reflow soldering SIC chip and DBC board in this paper,and the influence of the welding process temperature,welding time and welding packing pressure of transient liquid diffusion welding on the stress distribution and size of Cu@Sn@Ag solder layer for transient liquid phase diffusion welding,combined with elastoplastic deformation and other related theories were studied systematically.The results showed that when the welding temperature was 240~260℃,the peak stress of the post-welding layer gradually decreased with the increase of the welding temperature,and when the welding temperature was 260~280℃,the stress was minimal.When the welding insulation time was 30~90 min,with the extension of the welding insulation time,the stress of the layer remained unchanged,and the stress at the layer above 90 min begun.When the welding holding pressure was between 1~5 MPa,with the increase of the holding pressure,the stress at the welding layer also increased initially.Comprehensively considering the service performance of the device,when Cu@Sn@Ag solder lugs were used to reflow solder Si C chips and DBC boards,260℃was the suitable welding temperature,30min was the suitable welding holding time,and 1 MPa was the suitable welding holding pressure.

关 键 词：瞬态液相扩散焊 Cu@Sn@Ag焊片 焊接工艺 焊层应力 

分 类 号：TG453.9[金属学及工艺—焊接]