Characterization of FeSe thin films prepared on GaAs substrate by selenization technique

Abstract

FeSe thin films were prepared on GaAs(100) substrate by the selenization of Fe films using molecular-beam epitaxy. FeSe compound thin films were obtained at a substrate temperature above 380 °C. From the depth profiles of Fe and Se in the selenized film measured by Auger electron spectroscopy, it was confirmed that an FeSe layer with a constant ratio of Fe/Se was formed. The measured composition ratio of Fe/Se in the film was 1/3. It was different from the composition in Fe3Se4 or Fe7Se8, which is a stable bulk FeSe compound. From the measured M–H curve, it was found that the obtained FeSe film consisted of two phases with different magnetic properties.