A novel fabrication process for high-aspect-ratio and co-axial multi-layer nickel microstructures

A novel process of high-aspect-ratio metallic microstructures is proposed. The process combines protective film coating, laser drilling, swelling of polymers, electroforming and demolding. The pattern accuracy of metallic microstructures is controlled not only by laser drilling but also by swelling of polymers, because the diameter of drilled holes decreases to a certain value after the treatment of swelling. Using this process, a micro-post-array nickel mold and a precisely co-axial multi-layer nickel microstructure with a high aspect ratio of about 100 and a thickness of 5 mm is produced. The advantages of this process include low cost, simple procedures, and easy demolding.