Influence of deposition conditions on the composition, texture and microstructure of RF-magnetron sputter-deposited hydroxyapatite thin films

In this study, nanostructured hydroxyapatite (HA) coatings were deposited at a constant power via radio frequency magnetron sputtering. Substrate rotation was applied to increase the uniformity of the thin film properties. The crystallographic orientation, composition and microstructure of the coatings were examined. The characteristics of the deposited coatings associated with the applied deposition conditions were evaluated as a function of time that the samples spent under the target racetrack. The obtained thin films exhibit a change in out-of-plane orientation from preferential (002) to (300) and an increase in the Ca/P molar ratio when exposed for a longer time under the racetrack. This introduces the possibility of tuning crystallographic orientations of HA coatings