• SiNWs;
  • silver;
  • gold;
  • catalyzing;
  • etching


Silver and gold assisted etching of silicon in an HF aqueous solution is studied in this work. In the literature, we found that such etching leads to the formation of a variety of structures; i.e. silicon nanowires (SiNWs) or porous silicon (PS). It is also reported that the role of metals during the etching can be a catalyzing role (Peng et al., Adv. Mater. 23, 198 (2011) [1]) or a protective role (Qiun and Chu, Mater. Sci. Eng. R 61, 59 (2008) [2]). In addition, we found that for a sole experimental protocol, silver is described to have both roles. In this study, this apparent sole experimental protocol is divided into two different experimental ones; the one step process (OSP) and the two steps process (TSP). For each process, we propose an etching mechanism. We give experimental evidences arguing that the protective effect occurs during the OSP and the catalyzing effect occurs during the TSP. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)