Stabilized electronic state and its luminescence at the surface of oxygen-passivated porous silicon

Citation
Xl. Wu et al., Stabilized electronic state and its luminescence at the surface of oxygen-passivated porous silicon, PHYS REV B, 62(12), 2000, pp. R7759-R7762
Citations number
24
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICAL REVIEW B
ISSN journal
0163-1829 → ACNP
Volume
62
Issue
12
Year of publication
2000
Pages
R7759 - R7762
Database
ISI
SICI code
0163-1829(20000915)62:12<R7759:SESAIL>2.0.ZU;2-V
Abstract
Photoluminescence (PL) spectra of as-made porous Si samples were obtained i n a wide peak-wavelength range. After exposure to air or coupling with C-60 molecules, the PL peak shifts to a pinning wavelength within the range of 610-630 nm. This pinning wavelength is almost independent of the size of th e original porous Si nanocrystallites and both redshifting and blueshifting can occur for different sizes. A self-consistent effective-mass calculatio n shows that the Si=O binding states are responsible for the radiation of t his pinning wavelength and the blueshift for the large nanocrystallites is due to the additional potential modulation within the Si nanocrystallite by the long-range Coulomb interaction of oxygen ions.