Growth mechanism of [100]-oriented TaON film through an endotaxial transformation from a (012)-LiTaO3 single crystal substrate

Abstract

Metal nitrides are usually prepared by high temperature nitridation with metal oxide precursors under an NH₃ atmosphere. However, owing to the differences in crystal structures between oxide precursors and nitride products, the preparation of oriented nitride nanostructures is difficult and challenging. Our previous work has demonstrated that a [100]-oriented TaON film can be fabricated by using a (012)-LiTaO₃ single crystal substrate through an endotaxial transformation process. However, details about the endotaxial growth mechanism are still unclear. In this work, we systematically investigated the endotaxial growth process of TaON from the LiTaO₃ single crystal substrate, and proposed a plausible growth mechanism. This work could be helpful to deepen the understanding of the unique endotaxial growth process and facilitate the fabrication of other oriented nitride nanostructures.