Ferroelectric (Pb,La)(Zr,Ti)O3 epitaxial thin films on sapphire grown by rf-planar magnetron sputtering

Abstract
Ferroelectric (Pb,La)(Zr,Ti)O3 (PLZT) thin films have been epitaxially grown on the c plane of sapphire by rf-planar magnetron sputtering. The sputtering conditions were investigated to obtain epitaxial and transparent films. Dielectric, piezoelectric, and electro-optic properties of the films were measured. Piezoelectricity of the PLZT(28/0/100) film was confirmed and was as strong as that of BaTiO3. Excellent quadratic electro-optic effects for PLZT(28/0/100) and PLZT(9/65/35) films and a linear electro-optic effect for PLZT(21/0/100) film were observed at 0.633-μm wavelength. Epitaxial PLZT thin film on sapphire is presently the most promising material for new functional devices.