IUVSTA 15th International Vacuum Congress (IVC-15), AVS 48th International Symposium (AVS-48), 11th International Conference on Solid Surfaces (ICSS-11)
    Thin Films Tuesday Sessions
       Session TF-TuP

Paper TF-TuP14
Fabrication and Optical Properties of SiO@sub 2@ Sol-gel Made Thin Films Modified with Carminic Acid

Tuesday, October 30, 2001, 5:30 pm, Room 134/135

Session: Microstructure, Oxides, and Optical Properties Poster Session
Presenter: Yu.V. Vorobiev, Unidad Queretaro del CINVESTAV-IPN, Mexico
Authors: L.L. Diaz-Flores, Instituto Tecnolodico de Saltillo, Mexico
G. Luna-Barcenas, Unidad Queretaro del CINVESTAV-IPN, Mexico
J. Gonzalez-Hernandez, Unidad Queretaro del CINVESTAV-IPN, Mexico
Yu.V. Vorobiev, Unidad Queretaro del CINVESTAV-IPN, Mexico
Correspondent: Click to Email
SiO@sub 2@ sol-gel colored films on the glass slides were prepared by traditional process, using the precursor solution made of water, TEOS and ethanol, with the ratio of the components providing good structural quality of the films, and using the dip-coating apparatus. The carminic acid was introduced in the solution; special mechanical treatment of the solution was made to ensure good dispersion of the colorant. The films with intense and stable red color were obtained. The optical absorption spectra of the films contain all three visible absorption bands mentioned in the literature (494, 520 and 555 nm) as well as the UV band at 330 nm not reported earlier. The quantum mechanical description of energy spectrum of the system was attempted based on the modified FEMO approach, treating the carminic acid molecules as three-dimensional quantum wells and using the Born-von Carman boundary conditions corresponding to the mirror reflection of an electron delocalized inside the molecule, from its walls. Good agreement between the theory and experiment was obtained without any adjustable parameters.