Solid/Liquid Interface of Ag/Sn/Ag Trilayers by In Situ Resistivity Measurement

The in situ four-point probe resistivity measurement was used as a main method to study the solid/liquid interfacial characteristics in Ag/Sn/Ag trilayers at temperatures ranging from 150 to 305°C. It is found from the variation of resistivity that three processes take place on annealing: the dissolution of silver atoms, the diffusion of silver atoms, and the formation of Ag₃Sn in liquid tin layer. The first one plays the leading role in the variation of resistivity during annealing process. The apparent diffusivity of silver in liquid tin at 305°C is determined to be 7.3×10^-17cm²/s.