Effects of deposition and oxidation processes on magnetic and structural properties of iron oxide films

Osmium doped (0.75 at.%) iron oxide films were reactively sputter deposited onto Si substrates in an Ar + O2gas environment. The magnetic and structural properties of the as-deposited films depend critically on deposition process parameters such as O2flow rate, chamber pressure, substrate temperature, RF power and substrate rotation speed. The deposition process window has been determined for which only the spinel structure was observed. X-ray diffraction indicated films grown at a low O2flow rate of 3.0 sccm and a substrate temperature of 230°C had more random orientation and a lattice parameter closer to that of the bulk Fe3O4value. This condition produced a high saturation moment of 410 emu/cc. Increasing O2flow rate induced preferential