Antimonide-based depletion-mode metal-oxide-semiconductor field-effect transistors using small-bandgap InAs channel layers

Antimonide-based depletion-mode InAs channel metal-oxide-semiconductor field-effect transistors showing complete pinch-off characteristics are successfully demonstrated. The epitaxial antimonide materials are grown by molecular beam epitaxy and gate dielectrics are deposited by plasma-enhanced chemical vapor deposition. A device with a 2.0 μm gate length shows a drain current density of 600 mA/mm at VGS=0 V and a peak transconductance of 380 mS/mm at VDS=1.5 V. Charge trapping at the dielectric-semiconductor interface is observed using pulsed ID−VDS measurements and is explained as a primary cause for the degradation of frequency performance of the device.