Epitaxial growth of Fe3Si/CaF2/Si(111) hybrid structures by molecular beam epitaxy

Ferromagnetic Fe3Si/CaF2/Si hybrid structures were grown epitaxially on Si(111) by molecular beam epitaxy. It was difficult to prevent inclusion of FeSi in the grown films in the case that Si and Fe were directly deposited on the Si substrate. This problem was overcome by inserting a CaF2 epitaxial film between the Fe3Si and Si substrate. Fe3Si films were grown epitaxially on the CaF2 at 400 °C. A distinct square-like hysteresis loop with coercive field of approximately 20 Oe was obtained in the magnetic field dependence of Kerr rotation at room temperature (RT). The saturation magnetization was approximately 550 emu/cm3 at RT by a super conducting quantum interference device magnetometer.