Characterization of epitaxial thin films of Bi 2VO 5.5 on La-doped SrTiO 3 substrates prepared by coating-pyrolysis process

Abstract

Epitaxial thin films of Bi 2VO 5.5 (BVO) were prepared on La-doped SrTiO 3 (LSTO) by a coating-pyrolysis process. The BVO films were (001)- and (114)-oriented on LSTO(100) and (110), respectively. Atomic force microscopic observations showed that very dense surfaces were obtained in the BVO films annealed at 600 °C and p O 2 =10 −4 atm. The step heights of the BVO(001) film were in the range of 2–12 nm, each approximately corresponding to a multiple of the c-axis parameter of BVO. The low- p O 2 -processed and O 2-postannealed BVO films resulted in reproducible P– E hysteresis loops for both orientations, although somewhat leaky characteristics were observed at higher applied voltages. Anisotropic behavior based on the orientation difference was clearly observed.