The L-PVD of tantalum-oxide using tantalum target and KrF excimer laser was investigated experimentally in the formation of a high performance corrosion-resisting film.
This report describes the effects of oxygen pressure during ablation on chemical composition, surface morphology and crystal structure of formed films. An EMPA was used to determine the chemical composition of the deposited films.
Both the deposition rate of films and the oxygen content of deposited films increased gradually with increasing oxygen pressure up to 10Pa. The SEM images showed a smooth film surface in this pressure region. At 5Pa the oxygen/tantalum ratio of films measured was 2.5, which is equal to the ratio of Ta2O5. According to the XRD results, the films were amorphous. A crystallized Ta2O5 film, however, was obtained after annealing at 973K in vacuum.
Both the deposition rate of films and the oxygen ratio in deposited films indicated obvious saturation around 100Pa. At oxygen pressures higher than 50Pa, the surface of deposited films abruptly became porous.