回流焊温度对SnBi-SAC/ENIG焊点剪切强度的影响  

The effect of reflow soldering temperature on shear strength of SnBi-SAC/ENIG solder joints

作　　者：陈慧峰 姜梦夏 邱俊 曹荣幸 薛玉雄 CHEN Huifeng;JIANG Mengxia;QIU Jun;CAO Rongxing;XUE Yuxiong(College of Information Engineering,Yangzhou University,Yangzhou 225127,Jiangsu Province,China;College of Electrical,Energy,and Power Engineering,Yangzhou University,Yangzhou 225127,Jiangsu Province,China)

机构地区：[1]扬州大学信息工程学院,江苏扬州225127 [2]扬州大学电气与能源动力工程学院,江苏扬州225127

出　　处：《电子元件与材料》2024年第2期246-252,共7页Electronic Components And Materials

基　　金：国家重点研发计划(2022YFB4401303);国家自然科学基金(U22B2044);扬州大学大学生科创基金项目(XCX20230562);扬州大学创新创业学院大学生创新创业训练计划项目(C202311117024Y)。

摘　　要：针对有机电路板在回流焊接时的热变形问题,采用机械混合方法制备SnBi-SAC/ENIG复合焊点,研究回流焊温度对焊点微观组织和力学性能的影响。结果表明复合焊点在180℃下的剪切强度约为25 MPa,可满足芯片与基板预连接强度需求。随着回流焊温度的升高,复合焊点界面微观组织细化,存在弥散分布的小尺寸富Bi相与Ag_(3)Sn相。在250℃回流焊时,复合焊点强度提升至约55 MPa。该材料可适用于低温预连接-结构加固-高温回流的封装工艺,对抑制封装结构热变形具有显著效果。To suppress thermal deformation of the organic circuit boards during the reflow soldering,a mechanical mixing method was applied to prepare SnBi-SAC/ENIG hybrid solder joints.The effect of soldering temperature on the microstructure and mechanical properties of the solder joints was studied.The results show that the shear strength of the hybrid solder joint at 180℃is about 25 MPa,which can meet the pre-connection strength requirements for the bonding between chip and the substrate.As the soldering temperature increases,the interfacial microstructure of the composite solder joint becomes refined,and there are some small Bi-rich and Ag_(3)Sn phases dispersing near the interface.When the soldering temperature reaches 250℃,the shear strength of the solder joint increases to approximately 55 MPa.This material is suitable for the low-temperature pre-connection,structural reinforcement,and high-temperature reflow process.It has a significant effect on the thermal deformation suppression of the packaging structures.

关 键 词：回流焊 微观组织 剪切强度 复合焊点 

分 类 号：TG42[金属学及工艺—焊接]