A new ohmic contact system, Ge/Pt/Ge/Pt/n‐InP, was studied systematically by measuring its specific contact resistance and by using Auger electron spectroscopy, x‐ray‐diffraction analysis, Rutherford backscattering spectroscopy, and scanning electron microscopy. It was found that the system has a wide temperature range for annealing, i.e., 450–550 °C, to achieve the specific contact resistance of the order of 1.0×10−5&OHgr; cm2. It can achieve a low specific contact resistance of 7.71×10−6&OHgr; cm2when it is subjected to rapid thermal annealing at 500 °C for 30 s. The whole process is a solid phase reaction so that a smooth surface morphology is obtained. The ohmicity is due to the heavy doping of Ge in the regrown InP film. The contact system exhibits good thermal stability, being able to maintain a low specific contact resistance of 9.15×10−6&OHgr; cm2for 20 h, 400 °C aging, and 2.77×10−5&OHgr; cm2for 80 h aging. ©1995 American Institute of Physics.