Comparative study of Au–Sn and Sn–Ag–Cu as die‐attach materials for power electronics applications

A comparative study of Sn-3.0Ag-0.5Cu (SAC305) and Au-20Sn solders as die-attach materials for high-temperature power electronic applications was performed. The solid-state interfacial reactions of SAC305 and Au-20Sn solders with a Ni-plated Si chip and a direct-bonded-copper substrate, as well as the growth of interfacial intermetallic compound layers and interfacial stability, were investigated and compared during aging at 150 and 200 degrees C for up to 2000h. The SAC305 solder exhibited a higher interfacial intermetallic compound growth rate and a higher consumption rate of the Ni layer than the Au-20Sn solder. The Au-20Sn solder had a superior interfacial stability for high-temperature power electronic applications. Copyright (c) 2016 John Wiley & Sons, Ltd.