Analysis of charge sensitivity and low frequency noise limitation in silicon nanowire sensors

Abstract

This paper discusses the limit of the sensitivity that can be given to the design of nanowire sensors when the low frequency (LF) noise, due to trapping-detrapping at the nanowire surface, is taken into account. The sensitivity is calculated as the relative conductance variation per unit of external charge density. The LF noise is shown to limit the minimum detectable charge density. Our modeling approach shows how the performance can be optimized by tuning the channel length and the width, and the doping concentration. The implications of these developments are outlined as useful features for the design and the optimization of silicon nanowire sensors.