A study of mechanical properties of mesoporous silicon (PS) is presented in this article. PS was prepared by electrochemical etching of a heavily doped P⁺⁺ silicon wafer in a hydrofluoric acid electrolyte. The mechanical properties of PS and oxidized PS obtained by thermal treatment, were characterized by the nanoindentation technique associated to the continuous stiffness measurement option. The morphology of PS and oxidized PS were both characterized by scanning electron microscope. It is shown that the Young's modulus and hardness are related to the PS preparing conditions and decrease with increasing porosity. In particular, oxidation improves the mechanical properties of the mesoporous silicon. Surprisingly, modulus and hardness decrease with penetration depth, whereas a compaction could be expected resulting in a rising modulus and hardness. These results are mainly attributed to micro cracks formation, highlighted by focused ion beam cross section.

本文介绍了对介孔硅（PS）的机械性能的研究。PS通过重掺杂P ^++的电化学蚀刻制备硅片中的氢氟酸电解液。通过与连续刚度测量选项相关的纳米压痕技术，对通过热处理获得的PS和氧化PS的机械性能进行了表征。用扫描电子显微镜对PS和氧化PS的形貌进行了表征。结果表明，杨氏模量和硬度与聚苯乙烯的制备条件有关，并随孔隙率的增加而降低。特别地，氧化改善了中孔硅的机械性能。出乎意料的是，模量和硬度随着渗透深度而降低，而可以预期的是压实导致模量和硬度升高。这些结果主要归因于微裂纹的形成，其聚焦离子束横截面突出了这一点。