【摘要】 以电子封装线上的波峰焊无铅焊点Sn-0.7Cu/Cu、回流焊无铅焊点Sn-3Ag-0.5Cu/Cu为对象,研究了150℃时效过程中无铅焊点处金属间化合物(IMC)、焊料合金组织的演化规律及界面处金属间化合物生长的动力学。试验结果表明:两种无铅焊点处IMC层的厚度随着时效时间的延长而增加,IMC层的生长基本上符合抛物线规律,因此IMC层的长大受元素扩散控制;且两种无铅焊点处IMC层的生长速率常数相近,但Sn-0.7Cu焊料中Sn的晶粒尺寸较Sn-3Ag-0.5Cu中的大;长期时效后,在试样的IMC层内发现有孔洞产生。更多还原

【Abstract】 The effect of aging on the microstructure evolution and IMC growth kinetic of lead-free Sn-0.7Cu/Cu, Sn-3Ag-0.5Cu/Cu solder joints which come from real products was investigated.The results indicated that:the thickness of IMC increased with the aging time. The relationship between the thickness and the aging time of the two kinds of solder joints were according with the rule of parabola,namely the rate of atom diffusion affected the velocity of IMC growth.The value of IMC growth rate of the two kinds of solders were similar.The grain size of Sn in Sn-0.7Cu solder was larger than that in Sn-3Ag-0.5Cu.After long time aging,cavities were observed in the IMC layer.更多还原