K. Franke et al., HOW TO EXTRACT SPONTANEOUS POLARIZATION INFORMATION FROM EXPERIMENTAL-DATA IN ELECTRIC FORCE MICROSCOPY, Surface science, 415(1-2), 1998, pp. 178-182
To derive the spontaneous polarization of a sample, the first harmonic
signal of the electric force microscope (EFM) must be corrected using
the permittivity. This can be deduced from a simple EFM-force model a
nd has been verified in experiments. For thin films of high permittivi
ty, any gap of air between the tip and the sample prevents the accurat
e measurement of the permittivity. Therefore, the contact mode of EFM
has to be chosen for measurements of the spontaneous polarization of s
uch films. (C) 1998 Elsevier Science B.V. All rights reserved.