Propagation of polarization of ferroelectric grains in electrically isolated lithium niobate films

Piezoresponse force microscopy has been applied for the study of ferroelectric properties of lithium niobate thin films. The films have been obtained on a silicon surface {110}, coated with a thin layer of SiO2 using high-frequency magnetron spraying of lithium niobate. It has been demonstrated that after polarization of a sample surface segment with positive or negative potential using a conductive probe of an atomic force microscope the effect of propagation (spreading) of the region of grain polarized state with a decrease in the piezoresponse amplitude is observed. Moreover, the polarization occurs stepwise, that is, the Barkhausen effect takes place at the nanometer level.