Electric current effects on Sn/Ag interfacial reactions

The effect of electric current on the Sn/Ag interfacial reaction was studied at 140 degrees C and 200 degrees C, by examining the growth of phase (e-Ag3Sn) in the Sn/Ag reaction couples with a constant current density. Only at 140 degrees C was the growth of phase affected by the passage of electric current. The growth rate was enhanced when diffusion of Sn and electron flow were in the same direction, and retarded when they were in the opposite direction. It was found that the diffusion coefficient of Sn through Ag3Sn was 3.37 mu m(2)/h and the apparent effective charge for Sn in Ag3Sn was -90, at 140 degrees C.