Review—Through-Mask Electrochemical Micromachining

Abstract

Through-mask electrochemical micromachining (TMEMM) is a versatile microfabrication technique, which combines anodic metalshaping and -finishing steps in a single operation for the purpose of microstructuring a wide range of electrically conductive materials. It has been extensively utilized for the manufacture of precision-engineered components in microsystems, such as microlenses, microprobes, microactuators, microchannels and microvalves. This is because TMEMM is able to mass-produce parts; it is applicable to difficult-to-etch materials and operable under polishing conditions. This review provides an in-depth summary of the current state of TMEMM and presents key concepts relevant to its application. To this end, the interplay between the current distribution, mass-transfer effects and surface-film formation is discussed, and its effect on the machining rate, shape profile and surface finish is highlighted. Also, past incarnations of TMEMM are reviewed in terms of their masking method, substrate material, electrolyte composition and technical application. Techno-economic aspects of TMEMM are debated in relation to potential rival techniques, taking microreactor fabrication as an example for a novel area of application. This is followed by an overview of process variations and recent developments.

Investigation on particle assisted through-mask electrochemical etching of micro pits array

“…This phenomenon intensifies with increasing etching depth. Therefore, it is extremely challenging to improve the localization and uniformity of deep metal microstructures [20,21].…”

Large‐Scale Micropillar 3D Patterning with High‐Aspect Ratio Using a Theta‐Pipette

“…[ 5 ] At present, the most widely used method in the micro–nano manufacturing field is mask lithography. [ 6 ] However, this method requires a variety of complex processes, including vapor deposition, mask making, pattern development, and etching. Therefore, micro–nano technology still faces many challenges in the development of technology for manufacturing structure‐free microstructures.…”

Ultrasound-Assisted Through-Mask Electrochemical Machining of Hole Arrays in ODS Superalloy

“…As an ECM technology, through-mask ECM (TMECM) is primarily intended for micro-hole array processing with restraining the machinable region by using a thin insulation sheet with a specific pattern, and TMECM has been widely used to produce micro-structured components Materials 2020, 13, 5780 2 of 13 such as micro-dimples, hole arrays and micro-grooves. The research focuses of TMECM include the analysis of the forming process, the optimization of mask characteristics, and the improvement of electrolyte exchange [9]. In an analysis of hole-forming process, Li et al [10,11] established a numerical model and optimized the process parameters of TMECM, and then high-quality hole arrays were successfully fabricated on a structure of titanium alloy and molybdenum materials.…”