LIGHT-EMISSION IN THERMALLY OXIDIZED POROUS SILICON - EVIDENCE FOR OXIDE-RELATED LUMINESCENCE

The luminescence behavior of thermally oxidized porous silicon has been examined at various temperatures and times. No blue shifting of the photoluminescence has been noted with extended oxidation time (3-120 min), in a range where a 30% oxide thickness increase has been reported. This result does not easily fit the quantum confinement model, since the luminescence does not appear to depend on particle sizes. An oxide related luminescence, which is broad, in the red, and stable at high temperatures will be discussed as a possible source of this light emission.