Abstract: A system for coating the surface of compound semiconductor wafers includes providing a single-wafer epitaxial production system in a cluster-tool architecture with a loading, storage, and transfer modules, a III-V deposition chamber, and an insulator deposition chamber. The compound semiconductor wafer is placed in the loading and transfer module and the pressure is reduced to less than 5×10−10 Torr, after which the wafer is moved to the III-V growth chamber and layers of compound semiconductor material are epitaxially grown on the surface of the wafer. The single wafer is then moved through the transfer module to the insulator chamber and an insulating cap layer is formed by thermally evaporating molecules, consisting essentially of gallium and oxygen, from an effusion cell using a thermal evaporation source that utilizes a metallic iridium crucible that is manufactured using the electroforming process.

Abstract: A self-aligned enhancement mode metal-sulfide-compound semiconductor field effect transistor (10) includes a lower sulfide layer that is a mixture of Ga2S, Ga2S3, and other gallium sulfide compounds (30), and a second insulating layer that is positioned immediately on top of the gallium sulphur layer together positioned on upper surface (14) of a III-V compound semiconductor wafer structure (13). Together the lower gallium sulfide compound layer and the second insulating layer form a gallium sulfide gate insulating structure. The gallium sulfide gate insulating structure and underlying compound semiconductor gallium arsenide layer (15) meet at an atomically abrupt interface at the surface of with the compound semiconductor wafer structure (14). The initial essentially gallium sulphur layer serves to passivate and protect the underlying compound semiconductor surface from the second insulating sulfide layer.