Detection mechanism of spontaneous polarization in ferroelectric thin films using electrostatic force microscopy

Abstract

Mechanism on the detection of spontaneous polarization in a Pb(Zr0.5Ti0.5)O-3 (PZT) film using contact mode of electrostatic force microscopy (EFM) is investigated. Theoretical calculations are performed on deflections induced by electrostatic force (u(omega)(e)) between the tip and the sample and electromechanical vibrations (u(omega)(p)) of the ferroelectric materials, respectively. From the calculation, u(omega)(e) and u(omega)(p) are 3.73 x 10(-9) and 1.77 x 10(-13) m; Enhanced mode of EFM shows the complete cancellation of the EFM image induced by the electrostatic force between the tip and the film through controlling de voltage. Hence, electrostatic force effect is a main contributor on the detection mechanism of spontaneous polarization using EFM in contact mode.