Flicker Noises of AlGaN/GaN Metal-Oxide-Semiconductor High Electron Mobility Transistors

Abstract

AlGaN/GaN metal-oxide-semiconductor high electron mobility transistors (MOS-HEMTs) with gate insulators grown using the photoelectrochemical oxidation method were fabricated in this work. The pinch-off voltage, maximum extrinsic transconductance, and drain–source saturation current at were −9 V, 88.20 mS/mm, and 665 mA/mm, respectively. When the MOS-HEMTs operated at and 20 V, the gate leakage current was only 31 and 960 nA, respectively. The normalized noise power spectra of MOS-HEMTs operated in the linear region and the saturation region were fitted well by law from 4 Hz to 10 kHz. The exponent γ values were all closed to unity and independent of . In the linear region at and , the and estimated at a frequency of 100 Hz were and , respectively. The and estimated in the saturation region at and at a frequency of 100 Hz were and , respectively. The normalized noise power density was a function of , , and corresponded to the three regions of , , and , respectively, where was the effective gate bias defined as .