Fabrication of precisely controlled silicon wire and cone arrays by electrochemical etching

Materials Letters 63(29) 2567-2569

https://doi.org/10.1016/j.matlet.2009.09.005

Hong-Seok Seo, Xiaopeng Li, Han-Don Um, Bongyoung Yoo, Jae-Hyun Kim, Kang-Pil Kim, Yong Woo Cho and Jung-Ho Lee

Abstract

There is an exponentially growing need for well-oriented, vertical silicone nano/micro-structure arrays, particularly in high-density integrated electronic devices. Here, we demonstrate that precisely controlled vertical arrays of silion wires and cones can be fabricated by a combined treatment strategy of electrochemical and chemical etchings. First, a periodically ordered array of silicon wires was readily fabricated at microscale by simple electrochemical etching in which the current density played a critical role in determining the wire diameter and interspacing. The microstructures fabricated by electrochemical etching were more precisely tuned by further chemical etching, thereby transforming into cone arrays with extremely sharp tips where the cone height was controlled by the etching time. This approach could have broad utility in many electronics requiring miniaturization and high-density integration such as field emitters, photovoltaic and thermoelectric devices.