Epitaxial Growth and Magnetic Properties of Half-Metallic Fe$_{3}$ O$_{4}$ on Si(100) Using MgO Buffer Layer

The growth and magnetic properties of epitaxial magnetite Fe
₃
O
₄
on Si(100) using MgO buffer layer have been studied by reflection high-energy electron diffraction, X-ray photoelectron spectroscopy, and magneto-optical Kerr effect. The epitaxial Fe
₃
O
₄
films were prepared by
in situ
post growth annealing of ultrathin epitaxial Fe films at 220degC in an oxygen partial pressure of 8 times 10
^-4
mbar. The epitaxial relationship was found to be Fe
₃
O
₄
(100)lang001rang//MgO(100)lang001rang//Si(100)lang001rang with the MgO film grown cube-on-cube orientation with the Si substrate. While the Fe unit cell rotates 45deg to match that of the MgO buffer layer, it rotates 45deg back upon oxidation. A low saturation field has been observed indicating low density of antiphase boundaries.