Open AccessFLUORESCENCE SPECTRA OF Ge-NANOCRYSTALLITESEMBEDDED IN SiO2 THIN FILMS
Author(s) -
Yue Lan-Ping,
Yizhen He
Publication year - 1997
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.46.1212
Subject(s) - photoluminescence , materials science , thin film , luminescence , exciton , sputtering , radiation , fluorescence , optoelectronics , spectral line , nanocrystal , nanometre , quantum dot , optics , nanotechnology , condensed matter physics , physics , astronomy , composite material
The fluorescence spectra of Ge-nanocrystallites embedded in SiO2 thin films prepared by the ion-beam sputtering technique have been measured at room temperature.A strong visible photoluminescence with a peak at 2.95eV under exciting radiation of λ=300nm,and two luminescence peaks at about 2.95eV and 2.64eV under exciting radiation of λ=633nm are observed in the wavelength region of 380—520nm in the annealed samples.A possible mechanism for the photoluminescence in the visible region based on the quantum confinement of excitons in the nanometer-size Ge particles and recombination of the surface states has been proposed.The results also suggest that the interesting optical properties observed,of this new class of thin films with practical importance could be closely related to the new structure behavior of Ge-nanocrystallites,which is definitely different from that of the bulk Ge-crystals.