BiFeO3 thin films prepared by MOCVD

BiFeO3 thin films were grown by metal organic chemical vapour deposition (MOCVD) at the temperature T = 700 °C using Fe(thd)3, Bi(C6H5)3 as volatile precursors. High thermal stability of Bi(C6H5)3 makes the film stoichiometry very sensible to the deposition conditions, in particular to the precursor residence time in the reactor. We tested novel precursors Bi(thd)3 and Bi(CH3COO)3 possessing lower thermal stability. They drive the process into the diffusion control regime when cation stoichiometry in the layer is easier to control. The possibility to use them for epitaxial growth of BiFeO3 thin films was demonstrated. BiFeO3 film forms the self-organized nanodomain variant structure with (110) out-of-plane orientation on (001) ZrO2(Y2O3) substrate. The high resolution TEM images confirm variant domain structure formation. The ferroelectric nature of BiFeO3 films was assessed at the room temperature by piezoelectric force microscopy (PFM).