Fabrication of Truncated Silicon Pyramid Arrays by Electrochemical Etching

Abstract

A periodically ordered, truncated pyramid array of a single-crystal silicon was readily fabricated by simple electrochemical etching of a prepatterned silicon wafer. At potentials higher than the current peak (i(ps)), two reactions based on direct and indirect dissolutions of silicon occurred, which induced a topological variation in a surface profile, resulting in truncated silicon pyramid structures. The morphology of the silicon pyramids were precisely controlled by the electrochemical etching time and the applied voltage from the flat top to the sharp tip. The simple processing, flexibility, cost-effectiveness, and unique pyramid texturing make the silicon array promising for application to optoelectronic devices. (C) 2009 The Electrochemical Society. [DOI:10.1149/1.3231135] All rights reserved.