Toward the formation of three-dimensional nanostructures by electrochemical etching of silicon

We report a simple technique to form various kinds of three-dimensional structures in silicon. The process flow is only composed of two steps: lithography and electrochemical etching ("LEE"). The LEE process is an easy and low-cost solution for the fabrication of high-aspect-ratio structures such as walls, tubes, and pillars. Here we demonstrate the possibility to apply the LEE process on the submicrometer scale, indicating that it is a promising tool for silicon nanomachining. (c) 2005 American Institute of Physics.