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

Abstract

Photoluminescence ͑PL͒ spectra of as-made porous Si samples were obtained in 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 the original porous Si nanocrystallites and both redshifting and blueshifting can occur for different sizes. A self-consistent effectivemass calculation shows that the SivO binding states are responsible for the radiation of this 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.

Spherical Growth and Surface-Quasifree Vibrations of Si Nanocrystallites in Er-Doped Si Nanostructures

“…This result indicates that the visible PL has an origin related to the Si nanocrystallites [13]. Based on previous results [3,[13][14][15], we suggest that the visible PL arises from optical transitions in the Si --O binding states at the surfaces of Si nanocrystallites [4,[15][16][17].…”

Mo-containing diamond-like carbon films with blue emission

“…Thus it might be attributed to some surface states at g-MoC nanocrystallite surfaces. Similar to generally accepted theory on quantum dot luminescence [18,19], the photoexcitation of carriers takes place in the quantumconfined g-MoC nanocrystallites, while the radiative recombination occurs in states localized at the surfaces of g-MoC nanocrystallites. It could be noted from Fig.…”

Growth of Zinc Oxide Nanocombs on Porous Silicon Layer by Thermal-Evaporation Method

“…In other structures, the probability of the and holes will be higher, which confinement energy [39]. spectra of the ZnO nanocombs compared to the c-Si sample and the grown Si sample.…”