Influence of H2O atmosphere on the photoluminescence of HF-passivated porous silicon

Abstract
The influence of H2O atmosphere on the photoluminescence (PL) of HF‐passivated porous silicon (PS) is investigated in situ for samples oxidized in air during different times. The PL intensity is found to be strongly enhanced by H2O atmosphere up to exposure times of about 50 h and to decrease for longer exposure. The PL enhancement is strongest in the red region of the PL spectra. It is suggested that H2O atmosphere generates surface traps on the PS involved in the visible light emission.