【摘要】 研究了１５０℃等温时效对６２Ｓｎ３６Ｐｂ２Ａｇ／Ｎｉ－Ｐ／Ｃｕ及共晶ＳｎＡｇ／Ｎｉ－Ｐ／Ｃｕ表面贴装焊点微结构及剪切强度的影响．结果表明，在钎料与Ｎｉ－Ｐ间的界面存在Ｎｉ３Ｓｎ４金属间化合物层,其厚度随时效时间增加，Ｎｉ－Ｐ层的厚度减小；时效后，ＳｎＰｂＡｇ、ＳｎＡｇ焊点的剪切强度下降．对于ＳｎＡｇ焊点，时效２５０ｈ后其剪切强度剧烈下降，断裂发生在Ｎｉ－Ｐ／Ｃｕ界面上，在长时间时效后焊点一侧的Ｎｉ－Ｐ层中Ｐ的含量较高可能是Ｎｉ－Ｐ／Ｃｕ结合强度变差的主要原因．ＳｎＰｂＡｇ焊点保持着较高的剪切强度．更多还原

【Abstract】 The effect of aging on the microstructure and shear strength of 62Sn36Pb2Ag/NiP/Cu and SnAg/Ni-P/Cu surface mount solder joints was investigated. Intermetallic (IMC) layer of Ni3Sn4 was found in the interface between both solders and Ni-P layer and it thickens with aging time, meanwhile accompanied with a decrease of the thickness of remaining Ni-P layer. A drastic drop of the shear strength of SnAg solder joint happens after 250h aging and fracture was found to occur at the interface between Ni-P layer and Cu substrate. This may possibly be caused by the rapid accumulation of P in the remaining Ni-P layer. which results in a poor adhesion between Ni-P and Cu substrate. On the other hand, SnPbAg solder joint keeps a relatively higher value of shear strength even though it decreases with aging time.更多还原