Enhancement-mode metal-semiconductor field-effect transistors based on single n-CdS nanowires

Enhancement-mode (E-mode) metal-semiconductor field-effect transistors (MESFETs) based on single nanowires (NWs) were reported. The single NW used is n-CdS NW. Source-drain channel of the nano-MESFET is pinched off by the top surrounding Schottky gate at zero bias. When Schottky gate voltage (VG) changes from 0to0.25V, the source-drain current increases exponentially with VG, and an on/off current ratio of 5×103 is obtained. The maximum transconductance is 14.6nA∕V, and the gate leakage current is lower than source-drain current by more than two orders of magnitude. Their results suggest a way of fabricating E-mode nano-field-effect transistors.