Stabilization of the photoluminescence from porous silicon: The competition between photoluminescence and dissolution

Two experiments are reported which demonstrate the means to stabilize the photoluminescence from an electrochemically etched (100) Si surface (porous silicon). The strong stabilizing influence of small quantities of water on a nonaqueous [2 mol/l HF in methylcyanide (MeCN)] etching process and the stabilizing effect of hydrochloric acid on a porous silicon surface photoluminescing in solution are described. Mechanisms consistent with these observations are considered as they are commensurate with a silicon oxyhydride emitting species. (C) 1997 American Institute of Physics.