Annealing atmosphere influence on contact resistivity of ohmic Pd/Ge/Au contact to n-GaAs

We report the results of research for the Pd/Ge/Au ohmic contact resistivity to n-GaAs thermally treated in various gas atmospheres at low temperature. The lowest contact resistivity of about $4\cdot 10^{-6}$ $\Omega\cdot$cm$^2$ was obtained with annealing under a hydrogen atmosphere. The mechanism of the ohmic contact formation upon annealing under a hydrogen atmosphere has been proposed. The achieved results can be used for development of multi-junction solar cells, power semiconductor devices, lasers, and nanowire-based structures sensible to a high temperature treatment.