Cu Direct Nanopatterning Using Solid‐State Electrochemical Dissolution at the Anode/Polymer Electrolyte Membrane Interface

Abstract

Patterned copper (Cu) has applications in various electronic devices such as metal interconnects. Electrochemical approaches to patterning, such as electrochemical machining and electroplating, are promising methods for the direct fabrication of patterns on Cu surfaces. However, owing to the use of electrolytes, this technique suffers from issues such as low patterning resolution and significant environmental impact. Herein, a novel direct electrochemical patterning technique for the anodic dissolution of Cu using a polymer electrolyte membrane (PEM) stamp with a patterned surface instead of a liquid electrolyte, is proposed. In this technique, an electrochemical reaction selectively ionizes the Cu surface in contact with the PEM stamp, enabling the fabrication of patterns on Cu surfaces with a resolution of several hundred nanometers under a low‐temperature air atmosphere. Overall, the proposed all‐solid‐state electrochemical patterning technique employing PEM stamps offers a facile, environmentally friendly, and direct process that does not use resists or harsh chemicals, making it a cost‐effective approach that can improve processing efficiency.