The Effect of an Electrostatic Force on Imaging a Surface Topography by Noncontact Atomic Force Microscope

Noncontact atomic force microscope (NC-AFM) with and without scanning Kelvin probe force microscope (SKPM) has been studied to clarify the effect of an electrostatic force between a cantilever tip and a specimen on the NC-AFM imaging. The NC-AFM image contrast of a quenched Si (111) surface reflected the distribution of the surface potential, while that observed with a feedback of the SKPM signal showed good agreements with the previous results. The experimental results show that the electrostatic force affects the NC-AFM image formation, so that the electrostatic effect must be compensated to obtain an actual surface topography by NC-AFM.