Piezoelectric properties and surface potential behavior in LiNbO3 thin films grown by the radio frequency magnetron sputtering

Abstract

Abstract In this paper we report on using the atomic force microscope in piezoresponse and Kelvin modes to image grains, ferroelectric domains and surface potential in lithium niobate thin films. The radio frequency magnetron sputter system was used to deposit LiNbO 3 thin films on (1 0 0)-oriented Si substrate with SiO 2 layer. The surface of the sample showed small grains which diameter ranged from 70 nm to 130 nm and roughness less than 13 nm. Using the electric field from the biased conducting AFM tip showed that it was possible to form and subsequently visualize the ferroelectric state in LiNbO 3 thin films synthesized on electrically isolated silicon substrate. We also report on surface charge retention on ferroelectric thin films by Kelvin probe microscope in comparison with the piezoresponse signal. We also regard the possibility of retention of surface charge obtained by Kelvin probe microscopy in comparison with piezoresponse signal on ferroelectric thin films.