The characterization of InAs is known to have high spin–orbit interaction as well as high electron velocity, high sheet carrier density. In order to realize Datta–Das type spin field effect transistor (FET), it becomes crucial to develop thermally stable Schottky gate metal process for achieving a non-alloyed ohmic contact with ferromagnetic electrode after gate formation process. We have investigated Pd-gate deposited on In0.81Ga0.19As-based pseudomorphic heterostructures structure in order to check Pd as a good candidate for thermally stable Schottky gate by verifying good Schottky characteristics while maintaining good transport properties during heat treatment. Characteristics of Pd gate on InAlAs barrier layer was found to have Schottky barrier height of around 0.68 and less than 1.10 of ideality factor. Moreover Pd gate was found to endure higher heat treatment than Ti/Pt/Au gate or Ti/Au gate.