Cantilever effects on electrostatic force gradient microscopy

The effects of the cantilever on electrostatic force microscopy are discussed. Numerical calculations of the electrostatic potential distribution and force gradient for typical experimental geometries are presented. A simple analytical relation between the calculated force gradients with and without cantilever is found. The main effect of the cantilever is to reduce the electric field in the tip-sample gap and, as a consequence, the force gradient can be strongly reduced. This effect can be very important for dielectric films while it can be neglected for metallic samples. (C) American Institute of Physics.