Ohmic contacts with low specific‐contact resistivity and with contact morphology superior to conventionally alloyed contacts have been made ton‐type GaAs by sintering AuGe films on GaAs at 315 and 330 °C for several hours. The specific contact resistivities were found to decrease with sintering time and values as low as 3×10−6&OHgr; cm2were obtained for contacts on GaAs (doped with silicon to a concentration of 1018cm−3) after sintering at 330 °C for 1 h. Secondary Ion Mass Spectrometry profiling of the sintered films has been used to show that the ohmic contact formation is due to an enhanced diffusion of Ge into GaAs.