%0 Journal Article %K Stoichiometry %K Spatial distribution %K Electronic states %K Electronic structure %K Band gaps %K Growth conditions %K Semiconducting bismuth compounds %K Cathodoluminescence spectroscopy %K Defect emission %K Defect state %K Depth-resolved %K Film properties %K Interface electronics %K Localized electronic state %K Near-band edge emissions %A J Zhang %A M Rutkowski %A L.W Martin %A T Conry %A Ramamoorthy Ramesh %A J.F Ihlefeld %A A Melville %A D.G Schlom %A L.J Brillson %B Journal of Vacuum Science and Technology B: Microelectronics and Nanometer Structures %D 2009 %G eng %P 2012-2014 %R 10.1116/1.3130152 %T Surface, bulk, and interface electronic states of epitaxial BiFeO 3 films %V 27 %X The authors report on the depth-resolved cathodoluminescence spectroscopy studies of the surface, bulk, and interface-localized electronic states in the band gap of epitaxial BiFeO3 thin films. The BiFeO3 films show a near band edge emission at 2.7 eV and defect emissions at energies varying from 2.0 to 2.5 eV. The overall results clearly suggest that the electronic structure, especially the defect states and their spatial distributions, of BiFeO3 films are strongly dependent on the growth conditions and method, stoichiometry, and strain, so that understanding and controlling them are crucial to optimize BiFeO3 film properties. © 2009 American Vacuum Society.