多次回流对不同成分Sn-Pb凸点IMC生长的影响

Study on IMC Formation of Different Sn-Pb Bumps with Multiple Reflow Times

以不同成分Sn-Pb凸点为研究对象,分析回流次数对凸点IMC生长的影响。试验结果表明,多次回流中,5Sn95Pb凸点的剪切强度变化幅度最大,其余凸点抗剪切强度波动范围较小。凸点界面处IMC层厚度值均逐渐增大,其中3Sn97Pb和5Sn95Pb凸点界面处的IMC厚度增加速度较慢。界面IMC层晶粒尺寸逐渐增大,10次回流后,3Sn97Pb和63Sn37Pb凸点界面处观测到长轴状凸起,5Sn90Pb和10Sn90Pb凸点界面处IMC层呈现出较为平坦的形态。

In the paper, different components of Sn-Pb bumps are as research object, and impacts of the bump reflow times on IMC formation are analyzed. The main conclusions are as follows： Biggest change happened in 5Sn95 Pb bump shear strength and the rest have a smaller fluctuation range. IMC layer thickness of Sn-Pb bumps gradually increase, in which IMC thickness of 3Sn97 Pb and 5Sn95 Pb bump are slower.IMC layer grain size increase gradually, after 10 reflow completed, long axis can be observed in interface of 3Sn97 Pb and 63Sn37 Pb bumps and relatively flat shape exhibit in interface of 5Sn90 Pb and 10Sn90 Pb bump.