Li deficiencies in LiNbO3 films prepared by pulsed laser deposition in a buffer gas

The origin of Li deficiency in films grown by laser ablation of single-crystal LiNbO3 targets in a buffer gas has been investigated by analyzing the stoichiometry of the deposited films as a function of the following parameters: the distance target-substrate, the nature of the buffer gas (He, O-2, and Ar) and the deposition configuration. The results show that significant Li losses are related to scattering processes during the expansion regime which are higher the higher the mass of the gas species, The results show that the Li content of the films can be enhanced by setting the substrate either at distances larger than the plume length or in a configuration in which the substrate is not facing the target. (C) 1997 American Institute of Physics.