Observation of Polarization Distribution on Si(111) Surface by Scanning Nonlinear Dielectric Microscopy

Noncontact scanning nonlinear dielectric microscopy (NC-SNDM) has the ability to simultaneously acquire the surface topography and polarization distribution at the nanoscale through the measurement of local nonlinear dielectric constants of materials. NC-SNDM was here applied to the observation of Si(111) reconstructed surfaces. Images of the polarization distribution clearly distinguished disordered regions of the surface, often called $1\times 1$ regions, at the boundaries between the regular ($7\times 7$) domains. We acquired polarization images of surfaces with different sizes of $1\times 1$ regions and show that NC-SNDM has the potential to image trapped charges of surfaces and interfaces.