ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Using the x-ray excited optical luminescence technique, we have investigated the soft x-ray induced photoluminescence of porous silicon in the optical region (200–900 nm) and the Si K-edge x-ray absorption fine structures of porous silicon in the near edge region. It is found that while porous silicon prepared at low current density (20 mA/cm2 for 20 min) exhibits a single broad luminescence band, porous silicon prepared at high current density (200 mA/cm2 for 20 min) exhibits three optical luminescence channels; i.e., in addition to the broad peak characteristic of all porous silicon, there are at least two additional optical luminescence channels at shorter wavelengths, one with modest intensity at ∼460 nm and the other a weak and very broad peak at ∼350 nm. These optical channels have been used to monitor the Si K-edge absorption of porous silicon in the near edge structure region. Analysis of the data shows that while the band at ∼627.5 nm corresponds to the bulk emission, the other channels are of a surface origin. These observations and their implications are discussed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.355156
