INFLUENCE OF RAPID THERMAL-OXIDATION ON DIFFERENTLY PREPARED POROUS SILICON

Experiments with rapidly thermally oxidized porous silicon are presented. The samples are prepared from differently doped wafers (n-type and p-type) under various illumination conditions (dark, visual Light, UV light). Rapid thermal oxidation is performed using temperatures from 700 degrees C to 1200 degrees C. We describe the photoluminescence and the electroluminescence of the samples. The light-assisted samples show bright photoluminescence after etching, which is decreased by oxidation. On the other hand, the p-type samples etched in the dark show weak luminescence which increases with oxidation. All freshly oxidized samples show a PL energy below 1.7 eV. When these samples are hydrogen passivated after an HF dip, they show energies above 1.7 eV. The experiments can be explained using a smart quantum confinement model.