The epitaxial growth of cubic BiFeO3 ultrathin films on SrTiO3 (001) substrates by off-axis RF sputtering is demonstrated, suitable to X-ray spectroscopies interface investigation. X-ray photoelectron diffraction is used as a tool to probe the long-range crystal order and to track the transition from amorphous to epitaxial growth as a function of deposition parameters. Further spectroscopic measurements, in particular, X-ray linear dichroism on the Fe L 3, 2 edge, confirm the heteroepitaxial growth of BiFeO3 and clearly indicate a 3+ valence state for the iron cation. Finally, XPS is used to reconstruct the band alignment diagram, which results in a staggered configuration with a remarkable energy shift of the SrTiO3 band edges which can ultimately favor the n-type doping of SrTiO3.
Giampietri, A., Drera, G., Pis, I., Magnano, E., Sangaletti, L. (2016). Tracking the amorphous to epitaxial transition in RF-sputtered cubic BFO-STO heterojunctions by means of X-ray photoelectron diffraction. APPLIED PHYSICS LETTERS, 109(13) [10.1063/1.4963787].
Tracking the amorphous to epitaxial transition in RF-sputtered cubic BFO-STO heterojunctions by means of X-ray photoelectron diffraction
Drera G.
;
2016
Abstract
The epitaxial growth of cubic BiFeO3 ultrathin films on SrTiO3 (001) substrates by off-axis RF sputtering is demonstrated, suitable to X-ray spectroscopies interface investigation. X-ray photoelectron diffraction is used as a tool to probe the long-range crystal order and to track the transition from amorphous to epitaxial growth as a function of deposition parameters. Further spectroscopic measurements, in particular, X-ray linear dichroism on the Fe L 3, 2 edge, confirm the heteroepitaxial growth of BiFeO3 and clearly indicate a 3+ valence state for the iron cation. Finally, XPS is used to reconstruct the band alignment diagram, which results in a staggered configuration with a remarkable energy shift of the SrTiO3 band edges which can ultimately favor the n-type doping of SrTiO3.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.