Tungsten thin films onn‐InP layers have been investigated for potential use as a refractory ohmic contact for self‐aligned In‐based etched mesa buried heterostructure laser devices. The W films were rf sputter deposited onto InP substrates, S doped in the range of 1×1018–1×1019cm−3. The deposition parameters were optimized to produce films with the lowest possible induced stress, minimum argon content, and best morphology for as‐deposited wafers and after undergoing reactive‐ion etching and high‐temperature thermal cycles (700 °C), which are required for the self‐aligned technology. These parameters were obtained for films that were rf sputter deposited at a discharge power of 240 W and under argon pressure of about 10 mTorr. A thermal expansion coefficient of 5.84×10−6 C−1and a biaxial elastic modulus of 0.97×1012Pa were measured for the films. The electrical behavior of the W films sputtered onton‐InP was studied by means ofI‐Vand contact resistance measurements, which revealed a linear ohmic contact as‐deposited, while sputtered onton‐InP substrates, S doped to the level of 5×1018cm−3or higher. Rapid thermal processing at elevated temperatures improved the ohmic contact quality and decreased the specific contact resistance values to a minimum of 3.5×10−6&OHgr; cm2as a result of heating the W/InP (S doped 1×1019cm−3) at 600 °C.