Investigation of Temperature-Dependent Characteristics of AlGaN/GaN MOS-HEMT by Using Hydrogen Peroxide Oxidation Technique

This paper investigates the temperature-dependent performances of AlGaN/GaN metal-oxide-semiconductor high electron mobility transistor (MOS-HEMT). The gate dielectric layer and surface passivation layer are formed by the H₂O₂ oxidation technique. The gate dielectric quality is estimated by the breakdown electric field (EBD) and low-frequency noise. The capacitance-voltage (C-V) hysteresis characteristics of MOS and Schottky diodes at 300/480 K are also studied. An appropriate thermal model is used to investigate the self-heating effect and calculate the effective channel temperature (T_eff). The dc performances of the present MOS-HEMT are improved at 300/480 K, as compared with a Schottky-barrier HEMT (SB-HEMT), including output current density, maximum extrinsic transconductance (gm,max), gate voltage swing, gate-drain leakage current (IGD), specific ON-resistance (RON), three-terminal OFF-state breakdown voltage (BVOFF), and subthreshold swing. Factors that cause IGD and BVOFF are analyzed by the temperature-dependent measurement. The passivation effect of the present MOS-HEMT is also confirmed by the surface leakage measurement. The devised MOS-HEMT demonstrates superior thermal stability to the reference SB-HEMT. The present-design is promising for high-temperature electronic applications.