Strategies for High Quality Injection Moulding of Polymer Nanopillars

Injection moulding is a proven technology for high-throughput production of nanostructures, but replication of raised structures is a considerable challenge, due to the complexities of cavity filling. We have developed a platform to systematically study the effects of nanostructures with aspect ratios up to 1.2:1. A master template containing nanostructures with a continuous variation in height is produced by a novel fabrication approach using a plasma polymerized hexane layer, deposited with a thickness gradient, as a sacrificial etch mask. Results show that a careful choice of process parameters can control the stretching of nanopillar replica dimensions, allowing a variety of final pattern heights using a single master.