Micro array hole formation in glass using electrochemical discharge machining

Abstract

Abstract Electrochemical discharge machining (ECDM) is a process to create micro-features in electrically non-conductive materials like glass. The process has the capability to create micro-holes in glass, which can be used as ‘through glass vias’ in Micro-electromechanical system (MEMS) packaging. This work reports the fabrication of 3×3 array micro-holes in a glass substrate using ECDM. In order to improve the efficiency of the process, multi-tip array tools were used, where multiple micro-holes were fabricated at the same time. Fabrication of stainless steel multi-tip tool having a 3×3 array with an average tip size of 150 µm was demonstrated using Wire-EDM process. Issues related to multiple hole creation were discussed. Effects of applied voltage, pulse frequency and duty cycle on material removal rate (MRR) and heat affected zone (HAZ) width were observed. Ultimately, precise quality 5×5 array micro-holes were fabricated at the optimal range of input parameters.