Ohmic contacts on n-GaAs produced by spark alloying

A new method of forming ohmic contacts on n-GaAs using electroplated Sn/Au and alloying with a high frequency spark generator is described. This process gives an average contact resistance of 3.9×10¿6±0.2×10¿6 ¿cm2, which is comparable to results obtained by laser irradiation and indirect electric heating. The sparking technique produces uniform alloying of the substrate surface, while avoiding high temperatures throughout the substrate.