Progress in metal-assisted chemical etching of silicon nanostructures

Metal-assisted chemical etching (MACE) is a simple, low-cost method for fabricating silicon nanostructures. In this paper, the recent progress of MACE to control silicon nanostructures is reviewed. The principle of MACE is briefly summarized. The main influencing factors which decided the etching process and final morphology, such as metal substrate (type, deposition mode, distribution morphology), etchant concentration, etching temperature, etching time, light intensity and silicon substrate (doping type, doping level) are also discussed. Finally, the existing problems, the direction of research and development in the future are discussed.