title: Morphological, compositional, structural, and optical properties of Si-nc embedded in SiOx films.
abstract: Structural, compositional, morphological, and optical properties of silicon nanocrystal (Si-nc) embedded in a matrix of non-stoichiometric silicon oxide (SiOx) films were studied. SiOx films were prepared by hot filament chemical vapor deposition technique in the 900 to 1,400°C range. Different microscopic and spectroscopic characterization techniques were used. The film composition changes with the growth temperature as Fourier transform infrared spectroscopy, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy reveal. High-resolution transmission electron microscopy supports the existence of Si-ncs with a diameter from 1 to 6.5 nm in the matrix of SiOx films. The films emit in a wide photoluminescent spectrum, and the maximum peak emission shows a blueshift as the growth temperature decreases. On the other hand, transmittance spectra showed a wavelength shift of the absorption border, indicating an increase in the energy optical bandgap, when the growth temperature decreases. A relationship between composition, Si-nc size, energy bandgap, PL, and surface morphology was obtained. According to these results, we have analyzed the dependence of PL on the composition, structure, and morphology of the Si-ncs embedded in a matrix of non-stoichiometric SiOx films.
authors.affiliation: IC-CIDS Benemérita Universidad Autónoma de Puebla, Ed, 103 C o D, Col, San Manuel, C,P, Puebla, Pue, 72570, Mexico. jose.luna@correo.buap.mx.
authors.forename: J Alberto Luna
authors.initials: JA
authors.lastname: López
authors.forename: J Carrillo
authors.initials: JC
authors.lastname: López
authors.forename: D E Vázquez
authors.initials: DE
authors.lastname: Valerdi
authors.forename: G García
authors.initials: GG
authors.lastname: Salgado
authors.forename: T
authors.initials: T
authors.lastname: Díaz-Becerril
authors.forename: A Ponce
authors.initials: AP
authors.lastname: Pedraza
authors.forename: F J Flores
authors.initials: FJ
authors.lastname: Gracia