| Abstract Scope |
The solid/solid interfacial reactions of Sn/Au-xCu (x=15, 40, 60, 80 wt.%) couples at 150, 180 and 200˚C for 5 to 600 h were investigated in this study. The results indicated that (Au, Cu)Sn4, (Au, Cu)Sn, (Cu, Au)6Sn5 phases and Au-Cu-Sn ternary phase-B phase were formed in Sn/Au-15Cu system. The (Au, Cu)Sn, (Cu, Au)6Sn5, B phase and (Cu, Au)6Sn5, (Cu, Au)3Sn, B phase were formed in the Sn/Au-40Cu and Sn/Au-60Cu couples, respectively. The (Cu, Au)6Sn5, (Cu, Au)3Sn and B phase were observed in the Sn/Au-80Cu couple. Increasing the Cu content in Au-Cu alloys, reaction time and temperature, the formation of intermetallic compounds (IMCs) was gradually changed from Au-Sn system to Cu-Sn system. Meanwhile, the total IMC thickness was increased with the increase of reaction time and temperature. The IMC thickness was proportional to the square root of reaction time and IMC growth mechanism was diffusion controlled in the Sn/Au-xCu couples. |