Immersion Nanoimprint Lithography

Thermal nanoimprinting is used to modify a manufacturing process as simple fabrication technology that transfers a fine pattern by pressing a mold with nanoscale patterns against a thermoplastic. The molds can be categorized roughly into two types, namely, a positive mold with a convex pattern, and a negative mold with a concave pattern compared with the base level. Around each concave imprinted pattern, the compressed air that is caused by the imprint pressure, generates capillary bridges; and in case of a convex imprinted pattern the trapped air remaining inside the concave mold pattern gives rise to bubble defects. In order to remove such defective molding, I propose a novel technique that I name as "immersion nanoimprint" where a fluorine liquid is inserted between the mold pattern and the molding material. In this technique, a fluorine liquid improved accuracy remarkably, and realized a complete filling at a low imprint pressure. Also, it was confirmed that the uniformity was greatly improved by improved heat transfer. Thus the immersion nanoimprint lithography is expected to be one of the epoch-making solution that can dramatically decrease the formation of defective molding.

Autorentext

Harutaka Mekaru received his PhD degree in structural molecular science from the Graduate University for Advanced Studies in 1999. Currently, he is a senior researcher in Research Center for Ubiquitous MEMS and Micro Engineering, the National Institute of Advanced Industrial Science and Technology. His research interests in micro-/ nanofabrication.