Thin films of iron oxide by low pressure MOCVD using a novel precursor: tris(t-butyl-3-oxo-butanoato)iron(III)

Deposition of thin films of iron oxide on glass has been carried out using a novel precursor, tris(t-butyl-3-oxo-butanoato)iron(III), in a low-pressure metalorganic chemical vapor deposition (MOCVD) system. The new precursor was characterized for its thermal properties by thermogravimetry and differential thermal analysis. The films were characterized by X-ray diffraction (XRD), transmission electron microscopy, scanning electron microscopy, and by optical measurements. XRD studies reveal that films grown at substrate temperatures below ~550 °C and at low oxygen flow rates comprise only the phase $Fe_3O_4$ (magnetite). At higher temperatures and at higher oxygen flow rates, an increasing proportion of $\alpha-Fe_2O_3$ is formed along with $Fe_3O_4$. Films of magnetite grown under different reactive ambients—oxygen and nitrous oxide—have very different morphologies, as revealed by scanning electron microscopic studies