The porous silicon (PS) has many promising applications in silicon technologies development and integrated MEMS machining. Currently, many reports show that metal-assisted chemical etching can be a potential substitute for the electrochemical method. To broaden the fabrications and applications of porous silicon (PS), this research investigated the method based on silver-assisted chemical etching. Silvers particles were reduced by ascorbic acid under PVP protection, whose proper dosage was discussed. With the existence of oxidation component H2O2 and etchant HF, a silicon substrate can be etched into regular holes. The characterization results show that the silver-assisted etching structures may be spatially adjusted by disperse silver nanoparticles deposition. Furthermore, those porous silicon chips were proved to be energetic after dipping the certain concentration of nitrate, for violent exothermic when ignited. To sum up, controllable silver-assisted chemical etching provides a facile technique to fabricate PS that can be employed to realize wider manufacture.

Jin Chen, Xueming Li, Wenjing Yang, Yixuan Mou, Anqi Li, Yuting Xie, Yali Wang and Peng Xu. Facile Preparation of Porous Silicon from Silver-Assisted Chemical Etching Method on Silicon. Academic Journal of Engineering and Technology Science (2020) Vol. 3 Issue 1: 88-100. https://doi.org/10.25236/AJETS.2020.030112.

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