A novel approach for fabricating light-emitting porous polysilicon films

By etching back the as-oxidized polysilicon using reactive ion, a uniform porous polysilicon structure with significant enhancement of photoluminescence (PL) intensity was formed. We further found that the PL peak is centered at around 680 nm and is independent on the porosities or sizes of Si micropores. These results indicate the light emission in the samples should not be a consequence of the quantum confinement. Instead, the 680-nm peak should be due to the non-bridged oxide hole centers (=SiO.) at the oxidized grain boundaries of the polysilicon. (C) 2002 Elsevier Science Ltd. All rights reserved