Abstract
Whole field dark field monitoring system was constructed for observation of UV curable resin filling and detection of bubble defects of UV nanoimprint. Patterns with μm dimensions were observable by the monitoring system and filled/unfilled patterns were easily identified by the observed images. From full-area observations by the system, archipelago-like contact phenomenon was found in the contact front between a mold and UV curable resin on a wafer. The archipelagos were merged each other and were instantaneously banished with proceed of contact in the case of UV nanoimprint in pentafluoropropane (PFP). On the contrary, numerous bubbles were created even at unpatterned areas of a mold by the above phenomenon and were preserved for prolonged time in the case of UV nanoimprint in air. The portions detected by the monitoring system as unfilled were compared to the corresponding those images of UV nanoimprinted sample taken by an optical microscope at high magnifications. It was found that the monitoring system gives very correct evaluation of unfilled portions. The whole field dark field monitoring system is a simple but powerful tool for evaluation of resin filling processes.
