J. Phys. IV France 118 (2004) 119-125
DOI: 10.1051/jp4:2004118014
Étude structurale par rayonnement synchrotron de superréseaux d'oxydes pérovskites
M. Nemoz1, E. Dooryhee1, J.-L. Hodeau1 and C. Dubourdieu21 Laboratoire de Cristallographie du CNRS, BP. 166, 38042 Grenoble Cedex 09, France
2 LMGP, UMR 5628, ENSPG-INPG, BP. 46, 38402 St Martin d'Hères, France
Abstract
Perovskite oxides are analyzed by using high resolution synchrotron radiation diffraction. The diffraction profiles are fitted,
taking into account the structural and chemical disorders which depart from the ideal defect-free superlattice. Two types
of superlattices, (BaTiO
3/SrTiO
3)
15 and (La
0.7Sr
0.3MnO
3/SrTiO
3)
15, are synthesized by metal-organic chemical vapor deposition (MOCVD) on
oriented Nb-doped SrTiO
3 substrates. High-angle diffraction data show the excellent crystallinity and epitaxy of the films. For the (BaTiO
3/SrTiO
3)
n multilayers we observe a pseudo tetragonal symmetry with no difference between a and b axes, and they present a significant
strontium/baryum interdiffusion. The (La
0.7Sr
0.3MnO
3/SrTiO
3)
multilayers and their substrates almost have the same a=b parameter. Along the c axis, La
0.7Sr
0.3MnO
3 and SrTiO
3 have different lattice parameters. The crystallographic coherence of the stacking is higher in these samples.
© EDP Sciences 2004