Behavior of porous silicon crystallite size analized by Raman spectroscopy and phonon confinement model

Abstract

Porous silicon samples, obtained by electrochemical process in a solution containing HF-Ethanol were prepared varying etching time and current density. Using the phonon confinement model the crystallite size was estimated on the porous layer through the best fit of the Raman spectrum of first order. The experimental and theoretical points were better adjusted in order to obtain more accurate results in relation to previous works. For the samples with varying the anodization time and keeping constant the current density the crystallite size had an oscillating behavior and tendency to decrease as a function of the anodization time. Varying current density, keeping constant the anodization time, was observed an increase in the crystallite size as a function current density.