Demonstration of photoluminescence in nonanodized silicon

Abstract

The formation of photoluminescent porous Si in an etchant solution made from the HF-HNO3-CH3COOH system is reported. The porous Si is characterized on the basis of its photoluminescence (PL) spectra and the degradation of the PL during exposure to laser irradiation. The surface topography as characterized by atomic force microscopy (AFM) reveals features on the order of 400–600 Å. The effect of annealing the porous Si in vacuum on the PL intensity is described and correlated to the breakdown of Si—H bonds on the porous Si surface.