Fabrication of regular silicon microstructures by photo-electrochemical etching of silicon

In this paper photo-electrochemical etching of silicon in HF-based solutions is employed as a versatile technique for fabrication of original silicon microstructures, alternative to commonly used methods. Photo-electrochemical etching, a well known technique for regular macropore formation, has been exploited to produce a multitude of different regular silicon microstructures (microtubes, microtips, microchannels, microspirals, micropillars, microwalls, etc.). This micromachining technique is here detailed and some applications are reported.