Thickness dependence of submicron thick Pb(Zr0.3Ti0.7)O3 films on piezoelectric properties

The effects of thickness on the piezoelectric and electric properties of tetragonal composition, polycrystalline, (1 1 1)-textured Pb(Zr0.3Ti0.7)O3 films are investigated. The effective piezoelectric coefficient d33 is characterized by a double-beam laser interferometer and is measured to increase with film thickness although extrinsic contribution such as 90° domain wall motion is negligible from the nonlinearity of piezoelectric coefficient. Constituent parameters to affect piezoelectric coefficient such as polarization and dielectric properties were analyzed based on the semiempirical phenomenological equation. The effectiveness of poling was also evaluated as a function of film thickness. These results present that the increase of effective d33 in these tetragonal PZT films can be mainly due to enhanced intrinsic contributions.