热-剪切循环条件下Sn-3．5Ag-0．5Cu／Cu（Ni）界面化合物生长行为研究

对热-剪切循环条件下Sn-3．5Ag-0．5Cu钎料在Cu和Ni界面上原子扩散和化合物的生长行为进行了研究。结果表明：再流焊后，在Sn-3．5Ag-0．5Cu／Ni界面上形成（CuxNi1-x）6Sn5化合物；热-剪切循环200周次后，（NixCu1-x）Sn3化合物在（CuxNi1-x）6Sn5化合物周围以片状快速长大；而Sn-3．5Ag-0．5Cu／Cu界面从钎焊到热-剪切循环720周次始终只存在Cu6Sn5金属化合物层。随着热-剪切循环周数的增加，（CuxNi1-x）6Sn5和Cu6Sn5化合物形态均从笋状向平面状生长。界面金属间化合物的厚度随循环周数的增加而增加，且生长基本遵循抛物线规律，说明Cu原子的扩散控制了（CuxNi1-x）6Sns和Cu6Sn5化合物的生长。

Growth Behavior of Intermetallic Compounds on Sn-3.5Ag-0.5Cu/Cu(Ni) Interface under Thermal-Shearing Cycling Condition

In this paper,the atoms diffusion and growth behavior of intermetallic compounds(IMCs) on the Sn-Ag-Cu/Ni and Sn-Ag-Cu/Cu interfaces under the thermal-shearing cycling condition were investigated.The results showed that two kinds of IMCs,(CuxNi1-x)6Sn5 and(NixCu1-x)Sn3,formed on the Sn-Ag-Cu/Ni interface,but only Cu6Sn5 IMC layer formed on the Sn-Ag-Cu solder and Cu interface under the thermal-shearing condition of 720 cycles.The morphology of(CuxNi1-x)6Sn5 and Cu6Sn5 IMCs varied from scallop-type to planar-type with increasing the thermal-shearing cycling periods,while(NixCu1-x)Sn3 IMC formed surrounding(CuxNi1-x)6Sn5 IMC after 200 cycles.The IMC thickness increased with the increasing of thermal-shearing cycling periods by a role of parabolic growth kinetics,it implied that the IMC growth was controlled by Cu atom diffusion.