Preparation and Properties of LiTaO3 Thin Films by Dipping Method

Transparent and smooth LiTaO3 thin films 1000nm thick were prepared at 600°-800°C on platinum and fused silica substrates by the dipping method. Uniform grains were distributed in the films, and the grain size increased with increasing temperatures. Dielectric properties of the film depended on the defects of the film such as crack or pinhole. The crack-free film prepared at 800°C showed a symmetric D-E hysteresis loop. The spontaneous polarization was 0.6μC/cm2, remanent polarization was 0.4μC/cm2 and coercive field was 60kV/cm. Dielectric constant and dielectric loss angle were about 50 and 0.05, respectively. The optical transmission of the films was about 40-80% and refractive index was 2.1 in the visible region.