Improvements of defects by patterning using thermal nanoimprint lithography

Achieving excellent reliability for imprint patterns molded by stamps for the industrial application of nanoimprint lithography (NIL) is an important challenge. Usually, defects are produced by incomplete filling of negative patterns and the shrinkage phenomenon of polymers in conventional NIL. In our research, we investigated patterns that undergo varied temperature or varied pressure periods during thermal NIL with the goal of resolving issues dealing with the shrinkage and defective filling of polymers. The effects on the formation of polymer patterns in several profiles of imprint processes were also studied. Consequently, we observed that more precise patterns were formed with varied temperature (VT)-NIL and varied pressure (VP)-NIL. NIL has a free space compensation effect on the polymers in the stamp cavities. From the results of the experiments, the polymer's filling capability was improved. The VT-NIL was merged with the VP-NIL for a better filling property. The patterns imprinted using the merged NIL were compared with the results of the conventional NIL. In this study, an improvement in reliability from the results of thermal NIL was achieved.