Boxcar Averaging Based Scanning Nonlinear Dielectric Microscopy and Its Application to Carrier Distribution Imaging on 2D Semiconductors

Intermittent contact scanning nonlinear dielectric microscopy (IC-SNDM) has recently been applied to the nanoscale carrier or active dopant distribution imaging on two-dimensional semiconductors. However, IC-SNDM may suffer from a lower signal-to-noise (S/N) ratio than conventional contact mode SNDM due to the unoptimized detection of the signal only intermittently occurring. Here we show that S/N ratio can be much improved by applying the idea of boxcar averaging, which makes anomalous carrier doping on atomically-thin MoS
₂
clearly visible by IC-SNDM.