A Depletion-mode InP MOSFET with a Liquid Phase Oxidized InGaAs Gate

Abstract

We first report the characteristics of depletion-mode InP MOSFETs implemented by a liquid phase oxidation of In0.53Ga0.47As. The epitaxial layer structure of the InP MOSFET was grown by a chemical beam epitaxy (CBE). The n(+)-doped In0.53Ga0.47As layer, which was used for an ohmic contact and a gate oxide after oxidation, was oxidized using a gal lium-ion-contained nitric acid solution at 70 degreesC using the ohmic metal as a mask followed by an Oxygen plasma treatment. The current-voltage characteristics of MOSFETs having a 1.5x50 mum(2) gate showed a complete pinch-off characteristics with a relatively low pinch-off voltage (similar to -2.0V). The f(T) and f(max) of the transistor measured at V-gs of 0 V and V (ds) of 5.0 V were 10.5 and 70 GHz, respectively.