Large Schottky barriers formed on epitaxial InGaP grown on GaAs

We report the formation of Schottky contacts, with a barrier height as large as 0.9 eV, on epitaxial InGaP grown on GaAs wafers. The contacts are formed by removing surface oxide layers. Thermal reactions between Ti and InGaP and/or surface treatment with buffered hydrogen fluoride solution are effective for selective removal of surface oxide. These methods do not decrease the InGaP film thickness. They are promising for fabricating GaAs metal-semiconductor field-effect transistors with a thin InGaP film for increased barrier height.