中文摘要：

讨论了Sn—Ag-Cu焊料与Cu焊盘间在回流焊过程中形成的金属间化合物（IMC）的种类、形态，Ag含量和Cu含量对IMC的影响，IMC在老化过程中的生长演变及其对焊接性能的影响。结果表明：Sn—Ag—Cu焊料与Cu焊盘之间的金属间化合物主要是Cu6Sn5和长针状的Ag3Sn，Ag和Cu的添加对组织有明显细化作用，但过量添加会影响IMC的性能。IMC的演变主要是与老化温度、老化时间有关，较厚的IMC不利于焊接性能的提高。

英文摘要：

The kinds, morphology of the intermetallic compound （IMC） formed in the Sn-Ag-Cu solder and copper pad interface during reflow soldering, and the effect of the Ag and Cu content on IMC, the evolution of the IMC in aging, and the effect of IMC on the properties of the joint were discussed. The results show that the IMC formed in the Sn-Ag-Cu solder and copper is mainly Cu6Sn5 and Ag3Sn, Ag and Cu is available to the microstructure of IMC, but excessive content is harmful to IMC. The evolution of IMCs is related to the aging temperature and aging time. The thicker IMC is bad for the properties of IMC.