Composition control and thickness dependence of {100}-oriented epitaxial BiCoO_3-BiFeO_3 films grown by metalorganic chemical vapor deposition

摘要

xBiCoO_3-(l-x)BiFeO_3 films were deposited by metalorganic chemical vapor deposition. Although the film composition changed with deposition temperature, the composition could be adjusted by varying the input source gas composition at 700 ℃. Moreover, adjusting the deposition time could change 0.16BiCoO_3-0.84BiFeO_3 film thickness. The crystal symmetry changed from rhombohedral to tetragonal as the film thickness decreased for 0.16BiCoO_3-0.84BiFeO_3 films grown on both (100)SrTiO_3 and (100)_cSrRuO_3‖(100)SrTiO_3 substrates, implying that the x value of the crystal symmetry boundaries between the tetragonal and rhombohedral structures changes with film thickness.