Improved ohmic properties of Au–Ge Contacts to thin n-GaAs layers alloyed with an SiO2 overlayer

Abstract

The contact resistivity of Au–Ge contacts on n-type GaAs was reduced by about one order of magnitude by replacing the usual Ni top layer with an SiO2 layer. Surface coverage and edge definition of the contact areas can be optimised by proper choice of process parameters, making this technology suitable for submicrometre device processing.