J. Phys. IV France 11 (2001) Pr11-181-Pr11-185
Spectral ellipsometry of La1-xMnO3 films with different degree of epitaxyG.-J. Babonas1, A. Reza1, K. Fröhlich2, M. Pripko2 and D. Machajdik2
1 Semiconductor Physics Institute, Gostauto 11, 2600 Vilnius, Lithuania
2 Institute of Electrical Engineering, 84239 Bratislava, Slovakia
The dependence of the optical spectra of La1-xMnO3 films on the degree of epitaxy was investigated. Films of La1-xMnO3-δ (x 0.1) were grown by metal organic chernical vapor deposition on SrTiO3 and Al2O3 (r-plane cut) substrates. The films are supposed to possess a different degree of epitaxy because of various matching conditions between substrate and film lattices. The optical spectra were obtained in the range 0.5-5.0 eV by spectroscopic ellipsometry technique making use of photometric ellipsometer. Fine structure in the spectra of pseudodielectric function is discussed taking into account the excitations of Drude-type free electrons along with the charge-transfer 2 p(O) → 3d(Mn) and dipole-forbidden d-d(Mn3+) transitions. In this model the difference in the spectra of two type samples with different degree of epitaxy was considered.
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