Microstructure,wetting property of Sn-Ag-Cu-Bi-xCe solder and IMC growth at solder/Cu interface during thermal cycling  

作　　者：Yuan Wang Xiu-Chen Zhao Ying Liu Yong Wang Dong-Mei Li 

机构地区：[1]School of Materials Science and Engineering,Beijing Institute of Technology,Beijing 100081,China [2]Center of Packaging and Testing,Beijing Microelectronics Technology Institute,Beijing 100076,China

出　　处：《Rare Metals》2021年第3期714-719,共6页稀有金属（英文版）

基　　金：financially supported by the National Science and Technology Major Project of China(No.2011ZX02607)。

摘　　要：The effects of adding small amounts of cerium(Ce) to Sn-3.3 Ag-0.2 Cu-4.7 Bi solder on microstructure,wettability characteristic,interfacial morphology and the growth of interfacial intermetallic compound(IMC) during thermal cycling were investigated by optical microscopy(OM),scanning electron microscopy(SEM) and solderability tester.It is found that the p-Sn phase,Ag_(3)Sn phase and Cu6 Sn5 phase in the solder are refined and the wetting force increases.Ce is an active element;it more easily accumulates at the solder/flux interface in the molten state,which decreases the interfacial surface energy and reduces the driving force for IMC formation on Cu substrate;therefore,the thickness of IMC at the solder/Cu interface decreases when appropriate Ce was added into the solder.Moreover,the Ce-containing solders have lower growth rate of interfacial IMC than solders without Ce during the thermal cycling between-55 and 125℃.When the Ce content is 0.03 wt% in the Sn-3.3 Ag-0.2 Cu-4.7 Bi solder,the solder has the best wettability and the minimum growth rate of interfacial IMC layer.

关 键 词：Lead-free solder Rare earth element MICROSTRUCTURE WETTABILITY Intermetallic compound Thermal cycling 

分 类 号：TG42[金属学及工艺—焊接]