In0.53Ga0.47As∕InAs0.3P0.7 composite channel high electron mobility transistors

Abstract

An In0.53Ga0.47As/InAs0.3P0.7 composite channel high electron mobility transistor (HEMT) structure was grown by molecular beam epitaxy. Room-temperature Hall measurement showed that the device wafer had an electron mobility of 7300 cm2/V s and a sheet electron density of 3×1012 cm−2. The fabricated HEMT devices with a gate length of 0.25 µm exhibited excellent DC and microwave performance with a peak extrinsic transconductance of 888.3 mS/mm, a cutoff frequency (fT) of 115 GHz, and a maximum frequency of oscillation of 137 GHz. This is believed to be the first report of InGaAs/InAsP composite channel HEMTs. The fT is the highest ever reported for any composite channel HEMTs with the same gate length.