Electrochemical micromachining of micro square pattern using reusable masked tool

Abstract

Micro square pattern is the basic microfeature that can be applied to various products in different fields. The product duration and performance of textured surfaces are directly influenced by shape, size and surface quality. Maskless electrochemical micromachining (EMM) is a prominent method for producing numerous high-quality micro square patterns compared to photolithography and through-mask EMM, which are expensive and time consuming in mass production. In this paper, SU-8 2150 negative photoresist is used as a patterned tool in maskless EMM. Compared with other processes, this mask can be reused for generating many uniform micro square patterns. The maskless EMM setup consisting of EMM cell, electrode fixtures, electrical connections and vertical cross flow electrolyte system has been designed and developed indigenously for carrying out the experiments. Effects of major EMM parameters like interelectrode gap, flow rate and machining time on textured characteristics, i.e., current efficiency, length overcut, machining depth and surface roughness (Ra) are investigated during generation of micro square patterns. Arrays of 8000 micro square impressions have been fabricated during experiments. An attempt has also been made to analyze the textured characteristics on the basis of micrograph of micro square pattern for getting the best parametric combination.