Applications of Photocurable PMMS Thiol−Ene Stamps in Soft Lithography

We report the performance and characterization of a material based on poly[(3-mercaptopropyl)methylsiloxane] (PMMS) in various soft lithography applications. PMMS stamps were made by cross-linking with triallyl cyanurate and ethoxylated (4) bisphenol A dimethacrylate via thiol−ene mixed-mode chemistry. The surface chemistry of the materials was characterized by XPS when varied from hydrophilic through oxygen plasma treatment, to hydrophobic by exposure to a fluorinated trichlorosilane agent. The materials are transparent above 300 nm and thermally stable up to 225 °C, thus rendering them capable to be employed in step-and-flash imprint lithography, nanoimprint lithography, nanotransfer printing, and proximity-field nanopatterning. The successful pattern replication from the micrometer to sub-100 nm scale was demonstrated.