Non-alloyed ohmic contact to n-GaAs by solid phase epitaxy

A non-alloyed ohmic contact to n-type GaAs has been demonstrated. The technique of solid phase epitaxy through a transport medium has been used to obtain a metal/Ge(n+, epi)/GaAs(n, 〈100〉) heterostructure. The resulting contact displays a smooth surface and low contact resistivity (∼10-6-10-5 Ω cm 2) when compared with standard Au-Ge contacts on n-GaAs with similar doping concentrations (∼1018/cm3).