Fluorescence alignment simulation for atomic-scale position adjustment in ultraviolet nanoimprint lithography

Abstract

The alignment process of ultraviolet (UV) nanoimprint lithography requires a further sophisticated method to detect infinitesimal misalignments between a synthetic quartz mold and a silicon substrate. Previously, we proposed a fluorescence-alignment method based on the analysis of the additive-type moiré fringes generated by the interferences of fluorescence emission from fluorescent UV-curable liquid filling the concave bar-mark arrays on a synthetic quartz mold and a silicon substrate. The proposed method significantly reduces the cost of mold fabrication and simplifies the in-liquid process compared to the conventional method based on multiplicative-type moiré fringes prevailing in the industry. This is because the fluorescence-alignment method is free from the problem of the refractive index matching between mold and UV-curable liquid materials. However, its position accuracy remains as large as sub-10 nm scales in principle. In this study, through simulation using image drawing and analysis software, we demonstrate that a sophisticated fluorescence alignment can realize atomic-scale precision for position accuracy by attempting the following concepts: (i) the application of the principle on position determination of a fluorescent single-molecule to that of an individual bar-mark fluorescence signal; (ii) effective use of high bit-depth of recent imaging devices; and (iii) accumulations of the information on the positions of multiple bar-marks with periodicities by fitting their fluorescence intensity profiles using a periodic function.

Strong Light Confinement by a Plasmon-Coupled Parabolic Nanoresonator Array

“…To satisfy these requirements, for example, a thermal and photo nanoimprint method might be useful for the molding of concave surfaces . Additionally, the liquid- and gas-phase chemical growth method of the dielectric layer would be applicable for deposition on a substrate with a complex geometry. , Finally, the photo nanoimprint lithography process is optimal for forming metal nanostructures with highly accurate alignment. , …”

“…43,44 Finally, the photo nanoimprint lithography process is optimal for forming metal nanostructures with highly accurate alignment. 45,46 ■ CONCLUSIONS Here, we present a novel light confinement device that can accelerate the photoelectrochemical reaction at the nanoscale field under the modal coupling condition between the parabolic resonator array and LSPR. The parabolic resonator array harvests light in the near field based on the principle of constructive interference rather than a geometric condenser.…”