A new approach to produce porous silicon powder by chemical attack in phase vapor Marouan Khalifa, Malek Atyaoui, Messaoud Hajji and Hatem Ezzaouia Eur. Phys. J. Appl. Phys., 61 3 (2013) 30103 Published online: 20 March 2013 DOI: 10.1051/epjap/2013120194