Researchers at the Institute of Materials Research & Engineering (IMRE) and the National University of Singapore have used UV roll-to-roll nanoimprinting to fabricate high-fidelity resin moulds with nanoscale as well as mixed micro- and nanoscale features down to 50 nm feature diameter, at up to 120 cm2 in area and at a throughput of 10 m min–1.

In the study, the team also examined the effects of multiple iterative or descended copies from a nickel master out to the fourth generation, and through multiple material carrier types (nickel, UV cured acrylic resin, PMMA). Fabricated resin moulds were used in batch mode thermal nanoimprint lithography to demonstrate viability.

The scientists found that the combined feature shrinkage of a single UV curing replication cycle followed by thermal NIL was small enough to avoid substantially affecting replication fidelity and uniformity in terms of measured feature height.

The most significant uniformity bottleneck actually arises from the surface planarity of the resin mould itself, which depends specifically on the uniformity of curvature of the nickel shims and backing surfaces used in UV roll-to-roll nanoimprint fabrication. This highlights the need for engineered surfaces with near-perfect curvature, as well as further studies on defect accumulation after multiple iterative or descended copies with other roll-to-roll compatible mould materials such as fluoropolymers and polysiloxanes.

The researchers presented their results in the journal Nanotechnology.