多次回流焊后金属间化合物及焊点强度分析  

Analysis of Intermetallic Compounds and Solder Joint Strength After Multiple Reflow Soldering

作　　者：常青松[1] 徐达[1] 袁彪[1] 魏少伟 CHANG Qingsong;XU Da;YUAN Biao;WEI Shaowei(China Electronics Technology Group Corporation No.13 Research Institute,Shijiazhuang 050051,China)

机构地区：[1]中国电子科技集团公司第十三研究所,石家庄050051

出　　处：《电子与封装》2023年第8期41-44,共4页Electronics & Packaging

摘　　要：以BGA基板焊接为研究对象,分析了无铅焊料(SAC305)与NiPdAu镀层经过多次回流焊后金属间化合物(IMC)厚度与焊点强度的变化趋势。试验结果表明,通过优化SAC305锡球与Ni层焊盘的回流焊接温度曲线,IMC层的厚度可控制在2μm左右。同时,镀层中Pd的存在降低了(Cu,Ni,Pd)_(6)Sn_(5)生长的活化能,抑制了不良IMC的形成。经过多次回流焊后,SAC305锡球与NiPdAu镀层的微观界面和剪切强度仍然保持着较好的水平。经过回流焊3次后的焊点仍具有较高的可靠性。Taking the soldering of BGA substrate as the research object,the variation trends of intermetallic compound(IMC)thickness and solder joint strength after multiple reflow soldering between lead-free solder(SAC305)and NiPdAu plating layer are analyzed.The experimental results show that by optimizing the reflow soldering temperature curve between SAC305 solder balls and Ni layer pads,the thickness of IMC layer can be controlled at about 2μm.Meanwhile,the presence of Pd in the plating reduces the activation energy of(Cu,Ni,Pd)_(6)Sn_(5) growth and inhibits the formation of bad IMC.After multiple reflows,the microscopic interface and shear strength of SAC305 solder balls and NiPdAu plating layers still maintain a good level.The solder joints still have high reliability after reflow soldering for 3 times.

关 键 词：无铅焊料 金属间化合物 回流焊 焊点 

分 类 号：TN305.94[电子电信—物理电子学]