A novel method of induction electrode through-mask electrochemical micromachining

Through-mask electrochemical micromachining (TMEMM) is a key method for fabricating metal microstructures. However, the accuracy of TMEMM often falls short of the stringent requirements for many applications, primarily due to the uncontrolled electric field during the machining process. To overcome this limitation, this paper introduces a novel method: induction electrode through-mask electrochemical micromachining (IETMEMM). In this method, two feeder electrodes act as the anode and cathode, generating an electric field where the wireless workpiece is placed. This study explores the principles of electric field control in IETMEMM and develops a simulation model to highlight the method's unique advantages under specific electric field distributions. The findings indicate substantial improvements. Leveraging the self-stopping feature, a MEMS inertial switch was fabricated with high accuracy, achieving a non-uniformity of just 3.8%—a remarkable 96.2 % enhancement in accuracy compared to traditional TMEMM. Additionally, the gradient etching advantage facilitated the creation of both gradient-depth and V-shaped microchannel arrays. Moreover, the parallel machining advantage enabled the simultaneous fabrication of three identical microstructures in just 20 s. These outcomes demonstrate the significant potential of IETMEMM for industrial applications.