Low‐temperature migration of silicon through metal films importance of silicon‐;metal interface

The method of backscattering analysis has been employed to study the phenomenon of low-temperature migration of Si through thin films of Au and Ag evaporated in vacuum on substrates of single crystal Si. The Si begins to migrate at lower temperatures (≈200 °C) through Au, which has a low-temperature eutectic with Si, than it does through Ag (≈400 °C), which has a higher eutectic point. Migration of Si is also studied through double layers of Au with superimposed Ag, and vice versa. It is concluded that the interface between the Si substrate and the film plays a leading role in this process of low-temperature migration.