Microscale pattern transfer without photolithography of substrates

In this paper, we have described a process to transfer microscale patterns on a fully exposed (unpatterned) substrate. The method uses electrochemical means and a specialised electrochemical reactor for pattern transfer. This process uses a metallic material with a resist pattern, which serves as an electrochemical tool. The substrate, which is fully exposed, is placed facing the tool, within close proximity. The tool and the substrate are electrically connected so that the tool is the cathode and the substrate is the anode. Electrolyte is pumped through the system to deliver fresh solution to the anode and cathode as well as remove reaction byproducts. Our initial experiments, involving copper as the tool as well as substrate material, showed that microscale patterns could be transferred with good reproducibility. In our reactor, they were placed within a distance of 500 μm. We have successfully transferred micropatterns which are significantly smaller than the electrode gap, namely 50, 100 and 200 μm.