%0 Journal Article
%K thin films
%K molecular beam epitaxy
%K substrates
%K spectroscopic ellipsometry
%K bismuth compounds
%K Energy gap
%K Four-circle x-ray diffraction
%K Multiple-angle spectroscopic ellipsometry
%K Optical band gap
%K Oxygen activity
%A J.F Ihlefeld
%A N.J Podraza
%A Z.K Liu
%A R.C Rai
%A X Xu
%A T Heeg
%A Y.B Chen
%A J Li
%A R.W Collins
%A J.L Musfeldt
%A X.Q Pan
%A J Schubert
%A Ramamoorthy Ramesh
%A D.G Schlom
%B Applied Physics Letters
%D 2008
%G eng
%R 10.1063/1.2901160
%T Optical band gap of BiFe O3 grown by molecular-beam epitaxy
%V 92
%X BiFe O3 thin films have been deposited on (001) SrTi O3 substrates by adsorption-controlled reactive molecular-beam epitaxy. For a given bismuth overpressure and oxygen activity, single-phase BiFe O3 films can be grown over a range of deposition temperatures in accordance with thermodynamic calculations. Four-circle x-ray diffraction reveals phase-pure, epitaxial films with ω rocking curve full width at half maximum values as narrow as 29 arc sec (0.008°). Multiple-angle spectroscopic ellipsometry reveals a direct optical band gap at 2.74 eV for stoichiometric as well as 5% bismuth-deficient single-phase BiFe O3 films. © 2008 American Institute of Physics.