Influence of stress on the photoluminescence of porous silicon structures

Abstract

The blueshifting of photoluminescence spectra of porous silicon structures formed in p-type silicon is shown to be related to stresses in the porous material. A characteristic cellular structure, with varying length scale, is observed in the high porosity films due to high surface stresses. The cellular structure is not formed during the secondary open-circuit etching procedure itself but occurs during evaporation of the electrolyte after removal of the porous silicon from the etching solution.