  The extrinsic size effect in Piezoresponse Force Microscopy of ferroelectric
and piezoelectric thin films on non-polar dielectric substrate is analyzed.
Analytical expressions for effective piezoresponse, object transfer function
components, and Rayleigh two-point resolution are obtained. These results can
be broadly applied for effective piezoelectric response calculations in thin
piezoelectric and ferroelectric films as well as surface polar layers e.g. in
organic materials and bio-polymers. In particular, the effective piezoresponse
strongly decreases with film thickness whereas the sharpness of domain stripes
image increases due to the object transfer function spectrum broadening.
