3D molding of hierarchical micro- and nanostructures

We show a simple and effective process to produce large area, hierarchical 3D micro- and nanostructures via a modified hot embossing process, which we name 3D molding. The 3D molding process takes advantage of both a hard mold from hot embossing and the flexibility of a thin, elastomeric intermediate stamp from soft lithography. Using this method, we have demonstrated the formation of various micro- and nanostructures in non-planar microscale structures including microchannels and step surfaces. The ability to produce micro/nanopatterns within microchannels will have potential applications in bioanalytic micro/nanofluidic devices by allowing for the manipulation of a broader range of surface properties and thus control over surface interactions with biomaterials flowing through the microfluidic channels.