Effects of rotor electrode in the fabrication of high aspect ratio microstructures by localized electrochemical deposition

• Published in: Journal of micromechanics and microengineering 2001-09, Vol.11 (5), p.435-442
• Main Authors: Yeo, S H, Choo, J H
• Format: Article
• Language: English
• Subjects: Anodes; Applied sciences; Cathodes; Copper; Electrodeposition; Electrodes; Exact sciences and technology; Mechanical engineering. Machine design; Nickel; Nickel plating; Precision engineering, watch making; Rotation; Solutions
• ISSN: 0960-1317; 1361-6439
• DOI: 10.1088/0960-1317/11/5/301

This work reports on the effect of electrode rotation on the growth of nickel micro-columns fabricated by the localized electrochemical deposition (LECD) process - a new truly three-dimensional micro-rapid prototyping and direct-fabrication process capable of producing extremely high aspect ratio microstructures. The results shown here present a novel development in the area of LECD and a potential capability of the process for the fabrication of micro-pipes for possible applications such as medical drug delivery. Experiments were conducted on a specially assembled apparatus where nickel structures were electrodeposited onto Cu cathodes from a nickel sulfamate plating solution, using a non-soluble anode electrode. Deposition with electrode rotation produced columns with annulus cross sections, which indicate the existence of a uniform hollow core in the columns. This feature and dimensional control in the growth of the columns were not observed when using a stationary electrode. Micromechanical structures such as gears, springs, helices and columns are required for the realization of miniature micro-robots that can access spaces never before explored by human beings.