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Sloped and stepped 3D structures were added to surface-patterned resists using grey-scale electron beam lithography and thermal reflow. A poly(methyl methacrylate) resist with moderate initial molecular weight of 120 kg/mol was chosen, which enabled processing with both nanoimprint and electron beam lithography. Using proper exposure doses, a molecular weight distribution was generated that allowed a selective thermal postprocessing of the exposed steps while the imprinted gratings on top of the resist were preserved. This allows fabricating mixed structures of microprisms surrounded by large-area nanogratings in the same resist layer. Working stamps were casted from the template pattern and subsequently replicated using thermal nanoimprint. As a possible application, backlight devices with arrays of light outcoupling prisms can be seen. V

The organic-inorganic hybrid polymer Ormostamp was successfully used for the fabrication of inexpensive, transparent working stamps to be used in nanoimprint lithography. The stamps were produced from different masters by casting and UV exposure of a viscous precursor. The cured hybrid stamp with the replicated surface relief was imprinted into several thermoplastic materials with up to 180 °C imprint temperature. In this article the authors show the effect of the imprint temperature on the structural fidelity. By using combined thermal and UV-nanoimprint lithography at 110 °C imprint temperature, a resolution down to 35 nm is demonstrated. They also investigated deterioration effects due to plasma treatment to simulate the effect of multiple recoating steps.

We report the fabrication and field emission properties of high-density nano-emitter arrays with on-chip electron extraction gate electrodes and up to 10(6) metallic nanotips that have an apex curvature radius of a few nanometers and a the tip density exceeding 10(8) cm(-2). The gate electrode was fabricated on top of the nano-emitter arrays using a self-aligned polymer mask method. By applying a hot-press step for the polymer planarization, gate-nanotip alignment precision below 10 nm was achieved. Fabricated devices exhibited stable field electron emission with a current density of 0.1 A cm(-2), indicating that these are promising for applications that require a miniature high-brightness electron source.

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Fabrication of nanodot array molds by using an inorganic electron-beam resist and a postexposure bake Fabrication of 100 nm metal lines on flexible plastic substrate using ultraviolet curing nanoimprint lithography Hybrid transparent working stamps with both a surface relief and absorbing mask pattern were fabricated by replicating nanostructures in an Ormostamp film on prepatterned glass substrates. By using a combined nanoimprint and photolithography process, self-aligned mixed patterns of nanoand microstructures can be generated within one single resist layer. In this article the authors present a simple process based on the organic-inorganic hybrid polymer Ormostamp by replication on prepatterned Borofloat substrates. Using these working stamps, grating arrays with 35 nm half pitch were replicated in thermoplastic UV-curable resist. The method is easy to employ for generating mesas with nanostructures on top or the backfilling with microstructures in thermal nanoimprint lithography applications.

Arrays with hemispherical dots were produced from nanoimprinted line structures by thermal reflow and coagulation. By adding local nodes into 100 nm wide line cavities of the nanoimprint stamp, the coagulation was controlled and a self-ordered, highly regular dot matrix with almost totally dewetted lines was obtained. The forming of dots of almost equal sizes and distances along the line’s location shows that this coagulation effect is probably only restricted by geometry and surface energy. Simple resist preforms can be transformed into a more complex pattern by thermal-postprocessing in a controlled way.