Ohmic contacts to <i>n</i>-GaAs using In/Pd metallization

Abstract

Ohmic contacts to n-GaAs (Si doped at 2×1018 cm−3) with contact resistances of 0.7–1.5×10−6 Ω cm2 have been formed with deposited layers of In and Pd. The layers were sequentially evaporated and then annealed at 500 °C for 20 s to form In3Pd and a top layer of In. In addition a thin (≊200 Å) reacted layer was formed at the GaAs interface. Uniform interface morphology was observed with no evidence of localized reaction.