Artigo
Nanostructure and properties of ZnO films produced by the pyrosol process
Fecha
2003-06-01Registro en:
Journal of Applied Crystallography. Copenhagen: Blackwell Munksgaard, v. 36, p. 435-438, 2003.
0021-8898
10.1107/S0021889803000372
WOS:000182284400011
6466841023506131
5584298681870865
9971202585286967
0000-0002-3823-0050
0000-0002-8356-8093
Autor
Universidade Estadual Paulista (Unesp)
Universidade de São Paulo (USP)
GEMH
Resumen
Indium doped ZnO films were deposited by the pyrosol process on glass substrates at different temperatures from solutions containing In/Zn molar ratios up to 10%. The nanostructure of the films was investigated using grazing-incidence small angle X-ray scattering (GISAXS). The mass density was determined by X-ray reflectivity and the composition by X-ray photoelectron spectroscopy. The GISAXS measurements revealed an anisotropic pattern for films deposited at 573 and 623 K and a isotropic one for those deposited at higher temperatures. The anisotropic patterns indicate the presence of elongated nanopores with their long axes perpendicular to the film surface. In contrast, the isotropic nature of GISAXS patterns of films grown at high temperatures (673 and 723 K) suggests the presence of spherical voids. The pore size distribution function determined from the isotropic patterns indicates a multimodal size distribution. on the other hand, the measured mass density of the doped films with isotropic nanotexture is higher than that of the anisotropic films while the electric resistivity is significantly lower. This is in agreement with the detected strong reduction of the void density and specific surface area at approximately constant pore size.