A new approach to produce porous silicon powder by chemical attack in phase vapor

¹ Photovoltaic Laboratory Research and Technology Centre of Energy, Borj-Cedria Science and Technology Park, BP 95, 2050 Hammam-Lif, Tunisia
² Institut Supérieur d’Electronique et de Communication de Sfax, route Menzel Chaker Km 0.5, BP 868, Sfax 3018, Tunisia

^a e-mail: khalifa_marouan@yahoo.fr

Received: 21 May 2012
Revised: 11 January 2013
Accepted: 21 January 2013
Published online: 20 March 2013

Abstract

The aim of this work was to investigate a simple and effective method to produce porous silicon from a powder of silicon. The preparation of porous silicon (PS) was realized by exposing silicon powders to acid vapor attack issued from acid solutions containing a 48% of HF and 65% of HNO₃. The bond configuration of powder silicon before and after attack with acid vapor was monitored by Fourier transmission infrared spectroscopy (FTIR) and it was found that the PS was produced due to the newly formed Si-H bond during acid vapor attack. From the photoluminescence spectroscopy, it was shown that powder silicon attacked with acid vapor can lead to an increase of photoluminescence (PL) intensity when they are excited by light compared to untreated powder silicon and can provide blue shifts in the PL spectrum by increasing exposing time. This behavior may be attributed to the reduction in the size of the silicon, indicating consequently the formation of PS powder. The experimental results suggest a possibility that the chemical attack with acid vapor of the powder silicon provides a relatively easy way to produce porous silicon.