Impact of metal/oxide interface on DC and RF performance of D-mode GaAs MOSFET employing MBE grown Ga/sub 2/O/sub 3/(Gd/sub 2/O/sub 3/) as gate dielectric

Employing Ga/sub 2/O/sub 3/(Gd/sub 2/O/sub 3/) as gate dielectric on GaAs, prepared in a multi-chamber MBE system, has resulted in a low interfacial density of states (D/sub it/). The gate oxide is subjected to photoresists, solvents, water, and air before metallization, and as a consequence, contamination of the gate oxide is inevitable. The authors have studied the effects of gate oxide cleaning and etching before metallization on the DC and RF characteristics of depletion-mode GaAs MOSFETs with Ga/sub 2/O/sub 3/(Gd/sub 2/O/sub 3/) as gate dielectric.