X-ray diffraction and Raman study of nanogranular BaTiO3-CoFe2O4thin films deposited by laser ablation on Si/Pt substrates

✍ Scribed by Barbosa, J. ;Almeida, B. ;Mendes, J. A. ;Rolo, A. G. ;Araújo, J. P.

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 337 KB
• Volume: 204
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200675327

✦ Synopsis

Abstract

Nanocomposite thin films composed by (BaTiO~3~)~1–x~ –(CoFe~2~O~4~)~x~ with different cobalt ferrite concentrations (x) have been deposited by pulsed laser ablation on platinum covered Si(001) substrates. The films structure was studied by X‐ray diffraction and Raman spectroscopy. It was found that the CoFe~2~O~4~ phase unit cell was compressed along the growth direction of the films, and it relaxed with increasing x. The opposite behavior was observed in the BaTiO~3~ phase where the lattice parameters obtained from the X‐ray measurements presented a progressive distortion of its unit cell with increasing x. The presence of the strain in the films induced a blueshift of the Raman peaks of CoFe~2~O~4~ that decreased with increasing CoFe~2~O~4~ concentration. Cation disorder in the cobalt ferrite was observed for lower x, where the nanograins are more isolated and subjected to more strain, which was progressively decreased for higher CoFe~2~O~4~ content in the films. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)