Growth and optical properties of completely cc-axis orientated LiNbO3 films deposited by pulsed laser deposition

Completely cc-axis orientated LiNbO3 films have been deposited for waveguiding applications on SiO2/Si substrates by pulsed laser deposition without the application of external electric field or any other buffer layers. The stoichiometric LiNbO3 ceramic target was used. Drastic influences of the substrate temperature and oxygen pressure on the stoichiometry and cc-axis orientation of LiNbO3 films are shown. Completely cc-axis oriented and nearly stoichiometric LiNbO3 films can be grown at 600 ∘C in the oxygen pressure of 30 Pa. The films with column grain have smooth surface, uniform and small grain size, and the sharply defined interface. Favourable optical waveguiding properties of LiNbO3 films are demonstrated by the prism coupler technique.