Role of oxygen partial pressure and seed layer chemistry in flux mediated epitaxy of single phase multiferroic BiFeO3 thin films

Multiferroic BiFeO3 (BFO) thin films have been fabricated via flux mediated epitaxy with varying oxygen partial pressure and flux composition (Bi2O3:CuO) conditions. Transmission electron microscopy coupled with energy dispersive x-ray spectroscopy as well as piezoresponse force microscopy confirm, that with the correct flux and seed layer conditions, even at very low partial pressures (3mTorr) no secondary phases are formed. The study reveals the crucial role of the bottom seed layer and flux chemistry in epitaxy of BFO thin films and provides alternate routes to BFO epitaxy in oxygen-deficient environments.