LAUSR

The room-temperature and temperature-dependent photoluminescence spectra from as-grown and annealed porous polysilicon in the pure oxygen atmosphere have been measured and analyzed. The energy of blue emissions (B band) is independent on the measurement temperature, however; the intensity of the B band is decreased with the increasing measurement temperature. With the increasing measurement temperature, the band gap emissions of as-grown and annealed porous polysilicon at 300 °C show redshift. From the evolution of intensity with the measurement temperature, there are two different non-radiative recombination processes. At the low temperature range between 11 K to 80 K, the thermal quenching behaviors are due to the influence of the surface states. At the higher temperature range (from 80 K to 300 K), however, nonradiative recombination processes can be attributed to the thermal escape. We believe that the understanding of the defects is very beneficial for the application of the porous polysilicon in the optoelectronic device field.