Atomically controlled molecular beam epitaxy of ferromagnetic silicide Fe3Si on Ge

Low-temperature (60 deg. C) molecular beam epitaxy (MBE) of Fe3Si layers on Ge substrates was investigated. From x-ray diffraction and transmission electron microscopy measurements, it was shown that Fe3Si layers including the DO3 type were epitaxially grown on Ge(110) and Ge(111), while polycrystal Fe3Si was formed on Ge(100). Although the Fe3Si/Ge(110) interface was slightly rough (∼1 nm), the Fe3Si/Ge(111) interface was atomically flat. Such atomically controlled MBE of Fe3Si on the Ge(111) substrate can be employed to realize Ge channel spin transistors, which can be integrated with Si large-scale integrated circuits