Low-frequency Noise Characterization of Dry-etched and Wet-etched InAlAs/InGaAs HEMTs

Low-frequency noise (LFN) characteristics of dry-and wet-etched InAlAs/InGaAs HEMTS have been studied. It is found that due to passivation of deep traps by hydrogen the excess LFN (1/f and G-R) in dry-etched HEMTs is significantly lower than in wet-etched devices. All the traps as detected by LFN were found to be located in the InAlAs barrier layer.