Effect of gate length on the performance of InGaAs/InAs/InGaAs composite channel DMDG-HEMT devices

Abstract

In this work the Impact of gate length (Lg) on the performance of InGaAs/InAs/InGaAs Composite Channel DMDG-HEMT Devices for high-Frequency Applications is investigated. The gate length (Lg) effects on the device characteristics are explored by optimizing the barrier thickness (Tb). It is evident that by introducing dual material gate (DMG), at both top and bottom of the device, shows increase in drain current, transconductance and higher I on /I off ratio with less short channel effects (SCEs) are observed. For (Vds) =1V, InGaAs/InAs/InGaAs composite channel DMDG-HEMT devices exhibit the record drain current of Ids =4.42 × 10−3 A/um, transconductance (gm) = 4.48 S/mm, and I on /I off = 6.8 × 105 with reduced sub threshold slope (SS) of 62.1 mV/dec and a threshold voltage (Vt) = −0.12 V for 40 nm gate length.