Influence of surface states on the extraction of transport parameters from InAs nanowire field effect transistors

The capacitive effects of interface trap states in top-gated InAs nanowire field effect transistors and their influence on the experimental extraction of transport parameters are discussed. Time resolved transfer characteristics exhibit transient behavior indicating surface state trapping and detrapping with long characteristic time constants of 45 s. Varying gate voltage sweep rate results in a time-dependent extrinsic transconductance; a reduced gate voltage sweep rate leads to a charge neutral interface, reduced interface state capacitance, higher measured transconductance, and minimal hysteresis. These results demonstrate that measurements with a charge neutralized or passivated surface are key to extract intrinsic nanowire transport parameters.