Fabrication of Suspended Multilevel Three-Dimensional Silicon Micro- and Nano-Structures

摘要

A process for fabricating arbitrary-shaped three-dimensional silicon has been developed, based on high-energy ion irradiation, such as 200 keV to 2 MeV protons and helium followed by electrochemical anodization. This has enabled us to produce suspended complex microstructures such as arrays or long wires, grids, springs, vertically stacked wires and wires which can be controllably bent upwards and downwards in the vertical plane. By using a combination of multiple energy proton irradiation, and gray scale masks, different ion penetration depths and multilevel suspended three-dimensional silicon structures can be obtained in a single etch step.