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This study was performed to investigate dynamic resist filling in ultraviolet nanoimprint lithography. The effects of surface condition on flow behavior during the filling process, including the contact angle and the aspect ratio of recessed features, are presented through numerical simulations. The optimized surface conditions for good imprinting results were determined through numerical experiments covering a range of test conditions. A decrease in the feature aspect ratio of up to 0.5 resulted in a contact angle twice the original value. Complete filling occurred when the contact angle of the vertical side wall was as low as that of the substrate.

In this paper, a low-temperature plasma-assisted process is developed to realize a uniform, ultraviolet (UV) transparent and chemically inert quartz-to-quartz direct bonding. Two sets of pretests are performed in order to understand how the bond surface energy changes with the plasma exposure time and the wet etching of quartz, respectively. The developed technique is used to fabricate a multilayered quartz template for UV nanoimprint lithography (UV-NIL). The multilayered quartz template is fabricated by bonding a square piece of a standard quartz wafer, which is about 625 μm in thickness, to a wet-etched 6.35 mm thick quartz photomask plate. A fabricated multilayered template is loaded to the commercial UV-NIL tool Imprio TM 100, and NIL was performed successfully. The developed direct bonding technique makes it possible for standard quartz wafers, which are compatible with high-resolution semiconductor fabrication processes, to be utilized as the templates in commercial UV-NIL machines with enhanced mechanical stability.