We report the characteristics of InGaAs-oxide implemented by using a liquid phase oxidation and an oxygen plasma treatment and its application to depletion-mode In0.53Ga0.47As-channel metal oxide field effect transistor (MOSFET). The InGaAs-oxide characterized by using X-ray photoelectron spectroscopy (XPS), capacitance-voltage measurements showed excellent oxide/serniconductor interface characteristics. Depletion-mode (1.5 x 50 mu m(2)) In0.53Ga0.47As-channel MOSFET fabricated by using a conventional optical lithography showed a complete pinch-off and saturation characteristics. The f(T) and f(max) of the In0.53Ga0.47As-channel MOSFET were approximately 9 GHz and 10 GHz, respectively. The low frequency noise spectra of the In0.53Ga0.47As-channel MOSFET showed Ilf noise characteristics. The maximum differential transconductance frequency dispersion (triangle g(m)/g(mo)) appeared at T= 200 K and was measured to be as low as 9.0%. The results indicate the potential of the InGaAs-oxide implemented by using the liquid phase oxidation and oxygen plasma treatment for use in high-performance InP-based MOSFET applications. (c) 2006 Elsevier Ltd. All rights reserved.