The excess OFF-state current caused by band to band tunneling (BTBT) is a serious issue for short channel nanowire (NW) field-effect transistors (FETs), especially for semiconductors with narrow bandgap such as InAs. To suppress the OFF-state current and find way to improve the properties of short channel NW FETs based on semiconductors with narrow bandgap, we for the first time fabricate and study InAs NW FETs with nanoscale partial-gate (PG).

While compared with full-gate (FG) FET fabricated on the same NW, PGFET shows better OFF-state characteristics. Through studying the devices with different length of PG, different measurement conditions and fabrication processes, we find the excess OFF-state leakage current is mainly induced by the BTBT caused by the high-field at the drain-end of the channel, which can be obviously suppressed by the ungated region of PGFET. Through statistic study, we find BTBT effect can be more serious in the devices with better gate-control.