Electro-optic and dielectric properties of epitaxial Pb1 − 3x/2LaxZr0.2Ti0.8O3 thin films obtained by pulsed laser deposition

Abstract

The electro-optic behavior and dielectric properties of Pb1−3x/2LaxZr0.2Ti0.8O3, x=0.22 (PLZT 22/20/80) thin films have been studied due to the potential applicability of such composition in electro-optical devices. The PLZT (22/20/80) thin films, deposited by pulsed laser deposition, have been placed between specific conductive electrodes for obtaining the refractive index variation under the effect of an applied electric field. These birefringence variations have been measured by variable angle spectroscopic ellipsometry. PLZT films with different textures and orientations were obtained. Structural, chemical and morphologic properties of PLZT thin films have been investigated by X-ray diffraction, sputtered neutral mass spectroscopy and atomic force microscopy techniques. Piezoresponse properties have been also measured. Dielectric spectroscopy measurements have been used to characterize dielectric relaxation in thin film structures in the frequency range from 100Hz up to 1MHz, high values of dielectric permittivity (ε′~1400) and low dielectric loss (tanδ~2%) were being observed.