Investigation on Controllable Orientation Growth of BiFeO3 Thin Films Deposited by DC Magnetron Sputtering

Nanocrystalline BiFeO3 thin films were synthesized on single crystal SrTiO3(100) substrate by the magnetron sputtering method at a mixture of Ar/O-2 gas discharge, structure and morphology were characterized by x-ray diffraction (XRD) and scanning electron microscopy (SEM). The miscut angle of 4 degrees and 8 degrees for substrate and the effect of deposition temperature of 650 degrees C, 700 degrees C, 750 degrees C and 800 degrees C were discussed, respectively. The other two different crystal orientations substrates of SrTiO3(110) and SrTiO3(111), different miscut angles substrate SrTiO3(100) were selected to characterize orientation growth of BiFeO3 thin films. The results showed single phase nanocrystalline BiFeO3 thin films were synthesized at 700 degrees C-800 degrees C. The best crystallinity of BiFeO3 thin films was obtained at 750 degrees C with the grain size of 50 nm approximately. Via optimizing controllable orientation growth through varing the miscut angle, the orientation of the film sample can be regulated by the crystal orientation of different substrates, further proved that possessed different electric domain directions with change of miscut angle for substrate.