High-performance self-aligned InAs MOSFETs with L-shaped Ni-epilayer alloyed source/drain contact for future low-power RF applications

Abstract

In this study, InAs metal-oxide-semiconductor field effect transistors (MOSFETs) ultra-thin body (UTB) were fabricated with self-aligned method. 4 nm thick Al 2 O 3 gate oxide was deposited by Atomic Layer Deposition (ALD) technique. Ni-alloyed ohmic contacts for n-type source and drain (S/D) regions were formed at low annealing temperature (250°C). For a MOSFET with a gate length (L G ) of 150 nm, we obtained a maximum drain current (Ion) of 700 mA/mm, and the extrinsic transconductance (G M , max) showed a peak value of 500 mS/mm. The devices exhibited a current gain cutoff frequency f T of 100 GHz and maximum oscillation frequency f MAX of 60 GHz for drain to source voltage (V DS ) of 0.7 V.