Effect of a Fe3Si buffer layer for the growth of semiconducting β-FeSi2 thin film on stainless steel substrate

This paper reports a Fe3Si buffer layer for the growth of semiconducting β-FeSi2 film on stainless steel (SS) substrate. It was formed through the silicidation reaction of Fe and Si at a Fe-rich interface at an elevated temperature of 600 °C. β-FeSi2 film was deposited on it at low temperature around 400 °C. Auger electron spectroscopy depth profile showed that the inter-diffusions of Fe, Si and impurities contained in the SS substrate were effectively blocked by the buffer layer. The adhesive ability to SS substrate and crystallinity of β-FeSi2 film were clearly improved by the introduction of the buffer layer, thus also induced the decrease of residual carrier concentration, which was revealed by capacity–voltage measurement.