SU-8-based rapid tooling for thermal roll embossing

Rapid, flexible and low-cost tooling is particularly required in replication processes especially with small and medium volume as in research labs or startups. Epoxy stamps have been used in hot embossing and injection moulding since a few years. In this work, SU-8 epoxy-based patterns were generated on silicon wafers, which were employed as stamps in hot roll embossing of COC and PMMA foils using a commercial laminator. This method combines the accuracy of lithographic patterning of SU-8 resist with the mass production capability of roll embossing. The stamp fabrication process can be performed in less than a few hours using photolithography for tens to hundreds micrometer features and electron beam lithography for the sub-micronic range.