Manufacturing of Vertically Aligned One-Dimensional Copper Microwire Array Using PDMS Templates

Currently, the most widely used and commercially available templates for the electrodeposition of one-dimensional (1D) metal structures are anodic aluminum oxide (AAO) and polycarbonate track etched (PCTE) templates. Due to technical limitations in the fabrication process of these templates, their thickness is restricted to a few tens of microns (typically not exceeding 60 μm). However, some applications, such as advanced seal applications, require one-dimensional structures that are longer, up to hundreds of microns. In this study, polydimethylsiloxane (PDMS) templates with a thickness of 200 ~ 300 μm were prepared and used for the electrodeposition of Cu microwires (MWs) for the first time. The technical processes demonstrated here can be extended to prepare other 1D metal structures with customized geometry, length, diameter, and density, paving the way for new applications of 1D metal structures. Additionally, a scratch test was conducted on the synthesized Cu MWs array to examine the bonding strength of the Cu MWs array to the Cu substrate. The results showed that the Cu MWs array has a very strong bonding strength to its underlying Cu substrate, such that no delamination of Cu MWs occurred under a normal load of 3 N during scratch testing.