In-situ RHEED analysis of reactively sputtered epitaxial FeN thin films

Abstract

The properties of any material can be easily manipulated by employing an epitaxial thin film growth on a desired substrate due to the dependence of its 3D structure on the template used as a substrate as well as the effect of interface produced between the film and the substrate. However, to understand the modified properties, it becomes necessary to obtain a complete knowledge about the resulting atomic structure. In-situ reflection high energy electron diffraction (RHEED) has proven to be a very useful technique to monitor the structure of a surface as well as its crystallographic orientations. However, in-situ RHEED is generally used in film growth processes taking place under ultra-high or high vacuum conditions. Magnetron sputtering on the other hand, is performed at relatively higher pressures and the stray magnetic field generated from the magnetron source, interferes with the incident or reflected electron beam originating from the RHEED source. In this work, by overcoming these challenges, we employed the usage of in-situ RHEED technique in a magnetron sputtering system and have successfully demonstrated its ability to determine the growth mechanism of epitaxial iron mononitride (FeN) thin films.