Nano/Micro-Patterning of Semiconductors by Site Selective Chemical Etching Using Noble Metals as Catalyst

Controlled silicon structures on the micron to nanometer order have received much attention owing to their potential applications in various fields such as electrochemical, optoelectrical, and biological sciences. Although the techniques commonly used in fabricating nano-/microstructured silicon are conventional lithographic techniques using a resist mask with an optical, electron, or X-ray beam, chemical etching is also widely used in silicon micromachining. Three-dimensional silicon microstructures such as pillars, tubes, and macropores are fabricated by electrochemical etching in hydrofluoric acid (HF). This is a promising technique for the micromachining of silicon (Lehmann & Foll, 1990; Kleimann et al 2001; Matthias et al 2004).