Differential photoacoustic cell to study the wetting process during porous silicon formation

This paper shows the in-situ study of the wetting process in Silicon during anodization process using an electrochemical Differential photoacoustic Cell (DPC). The Photoacoustic amplitude and phase signals were obtained for samples in air, ethanol, ethanol/HF and finally air. According to these results ethanol is responsible for a mechanical contact reducing the superficial tension and ethanol/HF produce the removing of the SiOx and SiO2species on the Silicon surface. It was found that the DPC is a powerful technique to study the wet surface before the formation of the porous silicon layer (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)