(012) preferred orientation of LiNbO₃ thin films by RF-magnetron sputtering

LiNbO₃ films were prepared by an rf-magnetron sputtering technique using a sintered LiNbO₃ target containing potassium. The addition of potassium to the target enhances the mobility of the sputtered materials, through the re-evaporation of the potassium on the surface of the substrate during crystallization of the growth of the LiNbO₃. The enhanced mobility enables the growth of a LiNbO₃ film with a minimum surface energy structure without effect from the underlying layer. The rf power, working pressure, and substrate temperature were selected as process variables to investigate any changes in the preferred orientation of LiNbO₃. (012) preferred oriented films were fabricated within a deposition rate range from 25Å/min to 50Å/min. (012) preferred orientation of LiNbO₃ film is due to the minimum surface energy of (012) plane.