Study of Nanoimprinting Process and its Application for Infrared Detection

Abstract

Nanoimprint Lithography (NIL) is becoming a powerful tool for nanolithography, nanofabrication and nanomanufacturing for nanotechnology applications. However, there is still a lack of systematic study of key processing parameters, which determine the imprinted pattern quality in terms of uniformity and replication fidelity.This research focuses on identifying the most important parameters in a nanoimprint process, in which microscale patterns were imprinted into polymethyl-methacrylate (PMMA) polymer with polydimethylsiloxane (PDMS) mold. The effects of several parameters such as pre-imprint temperature, pre-imprint pressure, imprint temperature, imprint pressure, imprint time, venting temperature and venting time, were varied in a certain range during the imprinting process. The imprinting results were analyzed with a three-level design of experiments (DOE) analysis. It was found that the pre-imprint pressure and imprint temperature are the key parameters. In addition, the DOE analysis is a powerful tool for NIL process optimization.As a practice, a vacuum assisted and selective coating (VASC) method based on a commerical nanoimprinting tool was developed to fabricate micro-hole arrays on a PbSe nanocrystal film to study its spectral response to IR radiation for applications such as IR detection and photovoltaic. The process optimization significantly improves imprinting quality.© 2012 ASME