Single n-InAs Nanowire MIS-Field-Effect Transistor: Experimental and Simulation Results

We fabricated and characterised n-InAs nanowire field effect transistors. Nanowires were grown by metal-organic vapour-phase epitaxy (MOVPE) using the vapour-liquid-solid (VLS) growth mode. Metal-insulator field-effect transistors are fabricated using single n-InAs nanowire with a diameter of d = 50 nm as a channel and a silicon nitride gate dielectric. The gate length and gate dielectric variation are 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 from 20 nm to 90 nm while the gate length is varied from 1 mum to 5 mum. The InAs nanowire field-effect transistors exhibit an excellent saturation behavior and breakdown voltage values of V_BR > 3 V. The channel current divided by the diameter d of a nanowire 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 les 2 mum and a gate dielectric layer thickness les 30 nm. Based on Iniguez´s continuous charge control model for surrounding-gate MOSFET, the device is modelled and compared to experimental data. The good agreement verifies the validity of the model and provides detailed information on transport parameters available in InAs NW.