In this paper, a spectroscopic ellipsometry (SE) study was carried out on V
2O5 nanocrystalline thin films grown by plasma enhanced chemical vapor depo
sition. Both the real and imaginary part of the complex dielectric function
and, hence, the refractive index and absorption coefficients, were describ
ed up to a photon energy of 5 eV, taking into account the anisotropy of van
adium pentoxide and the influence of the films microstructure on the optica
l properties. A novel approach based on a suitable combination of Lorentzia
n oscillators was used to describe the V2O5 optical properties. The effect
of experimental parameters, such as deposition temperature and substrate, o
n the film microstructure and optical properties was investigated. (C) 2001
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