High-Speed, Low-Volume Inkjet and its Role in Jet and Flash Imprint Lithography

Imprint lithography is an effective technique for replication of nanoscale features. Jet and Flash™ Imprint Lithography (J-FIL™) uses field-by-field deposition and exposure of a low viscosity resist deposited by inkjet printing onto the substrate. The patterned mask is lowered into the fluid, where capillary action assists to flow the fluid into the relief patterns. Following the filling step, the resist is UV cured, the mask is removed, and a patterned resist is left on the substrate.J-FIL™ is a technique, where the imprint technology provides the nanoscale pattern resolution while the inkjet technology contributes the throughput that is required for industrial applications. The drop volume and drop placement accuracy of the inkjet-printed resist is critical, allowing the volume to be distributed appropriately across the substrate surface to achieve a uniform target thickness and preventing non-filling of the relief patterns. With J– FIL™, it is possible to resolve 28 nm structures with residual layer thickness of 13 and 20 nm on 300 mm and 450 mm Si-wafers.In this study, improvements during the filling step are explored for low droplet volumes at high ejection frequencies when using standard printheads with jetting performance of 12 kHz, <3 pL and modified printheads with jetting performance of 28 kHz, <2 pL.