High Transconductance MISFET With a Single InAs Nanowire Channel

Metal-insulator field-effect transistors (FETs) are fabricated using a single n-InAs nanowire (NW) with a diameter of
d
= 50 nm as a channel and a silicon nitride gate dielectric. The gate length and dielectric scaling behavior is experimentally studied by means of dc output- and transfer-characteristics and is modeled using the long-channel MOSFET equations. The device properties are studied for an insulating layer thickness of 20-90 nm, while the gate length is varied from 1 to 5 mum. The InAs NW FETs exhibit an excellent saturation behavior and best breakdown voltage values of
V

_BR
> 3 V. The channel current divided by diameter
d
of an NW reaches 3 A/mm. A maximum normalized transconductance
g_m
/
d
> 2 S/mm at room temperature is routinely measured for devices with a gate length of les 2 mum and a gate dielectric layer thickness of les 30 nm.