DC and RF characteristics of InAs-channel MOS-MODFETs using PECVD SiO2 as gate dielectrics

Abstract

Small-bandgap InAs channel materials are potential candidates for high-speed and low-power applications and have been demonstrated in AlSb/InAs/AlSb QWFETs. Taking advantage of their excellent transport properties, we successfully develop an InAs-channel metal-oxide-semiconductor modulation-doped field-effect transistor (MOS-MODFET) using 100-nm PECVD-deposited SiO2 dielectrics for gate dielectrics. A 2µm-gate-length depletion-mode InAs n-channel MOS-MODFET shows a maximum drain current of 270 mA/mm, a peak transconductance of 189 mS/mm, and a low output conductance of 18 mS/mm in dc characteristics, and a maximum current-gain cut-off frequency of 14.5 GHz and a maximum oscillation frequency of 24.0 GHz in rf performances. The InAs-channel MOS-MODFET presents potentials for further developing complementary circuit devices.