Growth and structure of tin dioxide thin films obtained by an improved spray pyrohydrolysis technique

Undoped and doped tin dioxide thin films have been prepared by an improved method of spray pyrohydrolytic decomposition of SnCI4-5H20 onto a glass substrate. We show that, with this overhead hot-plate and counter flux spray, the gravitational force plays an important role in distinguishing droplets...

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Detalles Bibliográficos
Autor: MARIO MIKI YOSHIDA
Tipo de recurso: artículo
Estado:Versión enviada para evaluación y publicación
Fecha de publicación:1993
País:México
Institución:Centro de Investigación en Materiales Avanzados
Repositorio:Fuente de Objetos Científicos Open Access del CIMAV
Idioma:inglés
OAI Identifier:oai:cimav.repositorioinstitucional.mx:1004/2239
Acceso en línea:http://cimav.repositorioinstitucional.mx/jspui/handle/1004/2239
Access Level:acceso abierto
Palabra clave:info:eu-repo/classification/spray pyrohydrolysis technique/SnO2
info:eu-repo/classification/cti/2
info:eu-repo/classification/cti/23
info:eu-repo/classification/cti/2307
info:eu-repo/classification/cti/221099
Descripción
Sumario:Undoped and doped tin dioxide thin films have been prepared by an improved method of spray pyrohydrolytic decomposition of SnCI4-5H20 onto a glass substrate. We show that, with this overhead hot-plate and counter flux spray, the gravitational force plays an important role in distinguishing droplets with a radius greater than 26 μm. X-ray diffraction spectra show that the structure is polycrystalline, with a grain size in the range 24-100 nm and a preferred orientation that is thickness dependent. It is shown by observations of the film microstructure by transmission electron microscopy that there is first an amorphous layer with embedded crystallites over which many crystals grow. This microstructure suggests that the films start to grow in an amorphous manner, then film growth continues with the nucleation of many small crystallites and finally some of them grow until a closely packed microstructure of crystallites is formed. Scanning electron microscopy of film surfaces indicates that surface roughness could be responsible for the large decrease in optical transmission of some films. Rutherford backscattering spectroscopy shows that film stoichiometry is close to the SnO2 phase and no significant chlorine contamination is present in the films.