Effect of Doped Nano-Ni on Microstructure Evolution and Mechanical Behavior of Sn-3.0Ag-0.5Cu (SAC305)/Cu-2.0Be Solder Joint during Isothermal Aging

The Cu-2.0Be alloy is widely used as the substrate in the aircraft electronic device, which has a potential trend to replace the pure Cu substrate. However, few studies have investigated the influence of the doped Ni nanoparticles on interfacial reaction between Cu-2.0Be substrate and the SAC305 solder during isothermal aging. In this study, the effect of doped nano-Ni on microstructure evolution and mechanical behavior of Sn-3.0Ag-0.5Cu (SAC305)/Cu-2.0Be solder joint during isothermal aging was studied. The result showed that the intermetallic compounds (IMCs) thickness of SAC305/Cu-2.0Be solder joint was thicker than that of SAC305-0.1Ni/Cu-2.0Be solder joint, which indicated that the composite solder's growth rate was smaller than that of monolithic solder. Furthermore, the SAC305-0.1Ni also had a smaller diffusion coefficient (1.65 x 10(-12) mu m(2)/s) than that of SAC305 (2.72 x 10(-12) mu m(2)/s). The SAC305-0.1Ni/Cu-2.0Be solder joint showed better mechanical property than that of SAC305/Cu-2.0Be solder joint. It indicated that a trace amount of Ni nanoparticle could hinder interfacial IMC layer's growth effectively. Therefore, SAC305-0.1Ni solder alloy is a promising potential solder alloy in electronic packaging field.