Pulsed laser deposition of iron oxide films

Iron oxide films have been grown onto MgO and oxidized silicon substrates using pulsed laser deposition with a KrF laser. Films deposited in vacuum consisted of the stoichiometric ferrimagnetic $γ-Fe2O3$ phase, with a saturation magnetization of $371±27 kA/m.$ However, films deposited in an $O2$ atmosphere were iron deficient and consisted of the antiferromagnetic $α-Fe2O3$ phase, with a saturation magnetization of $40±10 kA/m.$ Films predominantly consisting of the metastable $γ-Fe2O3$ phase at least 680 nm in thickness could be grown on MgO (001) substrates, which is thicker than films reported elsewhere. The effects of stoichiometry, thickness, and annealing on the magnetic properties of the films are discussed.