Surface potential analysis on doping superlattice by electrostatic force microscope

We have studied the surface potential profile of the doping superlattice by observing the cleaved edge of the doping superlattice sample with the electrostatic force microscope (EFM). The surface potential of the structure is estimated from the two frequency components of the electrostatic force between the EFM probe and the superlattice structure. Lateral resolution of the EFM measurements found to be about 200 Å. 2ω component was found to suggest an appreciable contribution in (∂C/∂z) term which might modify ω component result.