Photoelectron spectroscopy measurements of the band gap in porous silicon

Abstract

Photoemission and x-ray absorption spectroscopy show that both the conduction and valence bands of porous silicon are shifted relative to the bands for bulk silicon, as expected in the quantum confinement model for the optical properties of porous silicon. The shift in the valence band is larger than the shift in the conduction band and proportional to it, with a proportionality constant that is consistent with effective mass theory. No oxygen is detected in the as-prepared porous silicon.