An InAlAs/InGaAs metal-oxide-semiconductor field effect transistor using the native oxide of InAlAs as a gate insulation layer

Abstract

We report the growth, fabrication, and electrical characterization of InAlAs/InGaAs n-type depletion-mode, metal-oxide-semiconductor field effect transistors (MOSFETs) utilizing the thermally formed native oxide of InAlAs as a gate insulating layer. The native oxide of InAlAs, consisting mostly of aluminum–oxygen complexes, is formed in an elevated temperature environment with water vapor as the oxidizing species. This native oxidation process is similar to that used to oxidize other aluminum-containing compounds in the GaAs-based material system, such as AlGaAs and InAlP. The InGaAs MOSFETs having a gate length ∼8 μm exhibit a maximum gm∼6 mS/mm.