Optimizing the thermal budget for forming of nickel germanide on crystalline germanium

Nickel germanide is used as a contact material in germanium devices for making low resistance electrical contacts. It forms at relatively low temperatures compared to other germanides. Metal thickness, reaction temperature and duration of temperature are critical parameters. Here we report on the minimum temperature of formation of nickel germanide and on the effect of duration of temperature. Nickel germanide forms rapidly at higher temperatures and more slowly at lower temperatures and below a critical temperature it does not form, for any duration.