Deposition and optical characterization of lead-based ferroelectric films or integrated optics

Thin films of lead-based ferroelectrics have been grown by radiofrequency s puttering on various substrates for optical waveguiding purpose. The struct ure, the microstructure and the optical properties of the films have been s tudied as a function of the deposition parameters. Lead titanate (PbTiO3) h as been grown in-situ on (100) SrTiO3 substrates under optimized conditions . At the temperature of 550 degrees C, PbTiO3 films were completely c-axis oriented with a full width at half maximum (FWHM) of 0.26 degrees. Lanthanu m-modified lead titanate (Pb,La)TiO3 (28/0/100) have been prepared on (0001 ) sapphire with a post-deposition annealing of 600 degrees C, For the optic al characterizations, we have used the prism coupling technique. Refractive indices were found to be 2.61 and 2.37 at 632.8nm for respectively PbTiO3 and (Pb,La)TiO3 thin films respectively. Low optical loss of 2.2dB.cm(-1) w as evaluated in PbTiO3 waveguides, Electrooptic effects of PLT were investi gated using the change of the resonant coupling angle induced by the refrac tive index variation with the electric field is applied; The linear electro optic coefficient (r(13)) was about 55pm/V. These results illustrate the su itability of these materials for potential applications in integrated optic s.