Growth of Fe3O4 films on the Si(111) surface covered by a thin SiO2 layer

Magnetite polycrystalline films are grown by variously oxidizing a Fe film on the Si(111) surface covered by a thin (1.5 nm) SiO2 layer. It is found that defects in the SiO2 layer influence silicidation under heating of the Fe film. The high-temperature oxidation of the Fe film results in the formation of both Fe3O4 and iron monosilicide. However, the high-temperature deposition of Fe in an oxygen atmosphere leads to the growth of a compositionally uniform Fe3O4 film on the SiO2 surface. It is found that such a synthesis method causes [311] texture to arise in the magnetite film, with the texture axis normal to the surface. The influence of the synthesis method on the magnetic properties of grown Fe3O4 films is studied. A high coercive force of Fe3O3 films grown by Fe film oxidation is related to their specific morphology and compositional nonuniformity.