Pulsed-laser deposition and optical properties of completely (001) textured optical waveguiding LiNbO3 films upon SiO2/Si substrates

Completely (001) textured LiNbO3 films have been fabricated upon thermally oxidized SiO2/Si substrates by in situ application of a low electric field in a pulsed-laser deposition system. The biased voltage was 70-75 V on parallel electrodes separated by 7.0 mm. Li-enriched crystal and ceramic targets were used. The achieved films were nearly stoichiometric and have smooth surfaces. Waveguiding performance of the films was demonstrated by a prism-coupling method. The refractive indices were calculated on the basis of isotropic and anisotropic waveguide theories. A low-light propagation loss of 1.9 dB/cm in the films was achieved. It is expected that the films can be used in integrated-optical devices that require d(33), gamma(33), epsilon(33), and eta(33) elements. (C) 1996 Optical Society of America.