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NANO-IMPRINT LITHOGARPHY OF NANOSTRUCTURES Nano-imprint lithography is a useful and cheap method to replicate nanostructures and shows potential to replicate structures under the 100 nm scale. Current processes such as e-beam lithography and UV-lithography can be expensive, time consuming, and difficult to reproduce under the 100 nm scale. With imprint lithography, a large number of replicas can be made from one exposed master, insuring research and production throughput. Nano-imprinting is the molding of a polymer from a prefabricated master. The master can be produced using e-beam or UV lithography to define nm-scale patterns. A durable non-stick layer that can withstand high pressure and high temperature is then applied to the master. This coating is usually composed of hydrocarbon monomers and is important in order to prevent breakage and pull-off of the polymer. In this work the Si master is patterned by UV lithography and reactive ion etching and is coated with a self-assembled layer of octadecyltrichlorosaline for the non-stick layer. Once the master is produced (figure A), it is imprinted onto a host substrate bearing a polymer. The polymer used in this work is poly (methyl methacrylate) or PMMA. Depending on the temperature, pressure, and time, the polymer will flow and fill in the intended structures on the master. After the polymer flow is done, the sample is cooled and then the host is separated from the master to reveal a copy (figure B). In this work, key parameters for process the Si master and PMMA based imprint were determined.
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