Three dimensional micromachining on aluminum surface by electrochemical wet stamping technique

We proposed an up-down working mode of electrochemical wet stamping technique (EC-WETS) for three dimensional (3D) micromachining on aluminum (Al) surface. 3D microstructures on a Si mold were transferred on to an agarose hydrogel containing 15% NaNO3, 2% MgF2, 1% NaOH and 5% glycerin, which acted as the quasi-solid electrolyte for the electrochemical micromachining. The transferred 3D microstructures on agarose hydrogel were then duplicated onto Al surface through anodic dissolution. The micromachining quality was improved by pulse-potential method dramatically with a machining tolerance lower than 200 nm and an average removal rate of 210 nm min(-1) in the Z direction. This method was proved to be a highly efficient low cost and green method for 3D micromachining on active metal surface, which would be valuable for the manufacture of microelectromechanical system (MEMS). (c) 2013 Elsevier B.V. All rights reserved.