SnSe2 field-effect transistors with high drive current

Abstract

SnSe₂ field-effect transistors fabricated using mechanical exfoliation are reported. Substrate-gated devices with source-to-drain spacing of 0.5 μm have been fabricated with drive current of 160 μA/μm at T = 300 K. The transconductance at a drain-to-source voltage of V_ds = 2 V increases from 0.94 μS/μm at 300 K to 4.0 μS/μm at 4.4 K, while the field-effect mobility increases from 8.6 cm²/Vs at 300 K to 28 cm²/Vs at 77 K. The conductance at V_ds = 50 mV shows an activation energy of only 5.5 meV, indicating the absence of a significant Schottky barrier at the source and drain contacts.