Double-sided UV roller imprinting of microstructures on transparent plates

Abstract

UV roller imprinting is one of the most efficient mass-production processes for microstructure replication. Roller imprinting of microstructure on both top and bottom surfaces of substrate is challenging. The imprinting pressure has to remain uniform. Furthermore, it is difficult to irradiate UV light if both molds in the top and bottom are not transparent. In this study, air bearing was used to pressurize the top mold, which resulted in uniform non-contact pressure. UV light was irradiated from the lateral of the transparent substrate. An UV roller imprinting apparatus with air bearing pressing and lateral irradiating of UV light was designed and implemented. Pressure distribution measurements with pressure sensitive film proved that the air bearing provided a uniform imprinting pressure over a large area. V-groove microstructures with micrometer precision have been successfully fabricated on both sides of poly (methyl methacrylate) (PMMA) substrates over 98% replication rate. This study demonstrated lateral-irradiating, air bearing assisted UV roller imprinting has great potential for production of optical components with microstructures on both surfaces.