Improved Low-Frequency Noise and Microwave Performance of Enhancement-Mode InGaP/InGaAs PHEMT with a Liquid-Phase Oxidized GaAs without a Gate Recess

This paper demonstrates an enhancement-mode InGaP/InGaAs metal-oxide-semiconductor pseudomorphic high-electron-mobility transistor (PHEMT) with a liquid-phase oxidized GaAs gate without a gate recess. Without a gate recess, the gate insulator is obtained directly by oxidizing the GaAs capping layer in the LPO growth solution, and fully planar surface is achieved around the active region. The proposed device shows a maximum transconductance of 141 mS/mm at V-DS = 2 V and a maximum drain current density of 145 mA/mm at V-GS = 2 V and V-DS = 2 V. It also exhibits lower leakage current, improved subthreshold swing, suppressed low-frequency noise, and enhanced microwave performance than those of the referenced PHEMT. (C) 2012 The Electrochemical Society. All rights reserved.