Electrochemical micromachining of titanium through a patterned oxide film

Abstract

Electrochemical micromachining of titanium through a patterned oxide film (oxyresist) has been achieved in a sulfuric acid-methanol-based electropolishing electrolyte. The patterned oxide film was formed in an aqueous 0.5 M sulfuric acid solution by selective anodic oxidation of titanium through a photoresist mask. Electrochemical dissolution through the patterned oxide film yielded well-defined grooves comparable to those obtained by etching directly through a photoresist mask. The described process eliminates the need for photoresists to be chemically stable in aggressive electropolishing electrolytes. It increases significantly the flexibility of implementation of electrochemical micromachining of valve metals.