Published online by Cambridge University Press: 25 February 2011
Alloyed Au/Te/n–GaAs ohmic contacts, with contact resistivities comparable to those of the AuGe device standard, have been developed and studied by Mässbauer spectroscopy, Raman scattering and X-Ray Diffraction. The formation of Au-doped Ga2Te3 crystallites, grown epitaxially on a defectively GaAs surface was observed. No evidence for the formation of an n++–GaAs surface layer could be derived. The interpretation of all experimental results leads to a description of the ohmic conduction mechanism based on a resonant tunneling process assisted by defect/impurity related deep levels through low barrier metal/Te/(Au)Ga2Te3/GaAs interfaces