A novel fabrication method based on an after thermal oxidation process for the realization of silicon-beams with normative polygon cross sections shapes

Abstract

This paper presents a novel method to obtain structures with normative polygon cross section (PCS) shapes in a single crystal silicon substrate. A combination of wet etching and an after thermal oxidation (ATO) technique was used to fabricate several novel, complex structures with PCS shapes, which can hardly be fabricated by traditional wet etching. Based on such an innovative method, this paper proposes and develops three varieties of PCS silicon-beams. The subsequent experiment of fabricating silicon-beams with hexagonal sections has been taken as an example to validate the technique principle. Furthermore, the dimension parameters of the fabricated structures have been tested. Through this novel fabrication method, the sidewall arris of the fabricated silicon-beams can be maintained due to the protection of the ATO SiO2 layers, the arris disfigurement of the silicon-beam decreases dramatically and the quality of the silicon-beam is improved greatly.