UV-nanoimprinting using non-transparent molds and non-transparent substrates

A new ultraviolet assisted nanoimprint lithography technique with an exposure through non-transparent molds and a nm-resolution capability is reported. The UV imprint material was not cured by direct irradiation, but substantially exposed to indirect and diffuse irradiation. The nanoimprint molds consisted of a transparent support and a non-transparent, patterned element. Successful imprints were conducted on transparent glass and polymer foils placed on non-transparent substrate holders as well as on SiO₂ on Si. The reported technique enables the application of non-transparent mold materials like Si, new mold materials and alternative antisticking layers like metals in UV-NIL.