Photoluminescence and photoexcitation spectra of porous silicon subjected to anodic oxidation and etching

The photoluminescence and photoexcitation spectra of porous silicon films with an initial porosity of 50–60%, produced on single crystals of p-type silicon and subjected to anodic oxidation and chemical etching, are studied. The existence of an amorphous phase in the etched porous silicon is found not to affect the photoluminescence spectrum of porous silicon. Features of the photoexcitation spectra before and after etching, as well as the evolution of the photoluminescence and photoexcitation spectra after etching, can be interpreted in terms of a uniform quantization model that includes elastic stresses in the silicon crystals of the porous silicon.