High resolution 3D NanoImprint technology: Template fabrication, application in Fabry–Pérot-filter-array-based optical nanospectrometers

[Display omitted] •We developed the methodology of fabricating 3D NanoImprint templates.•3D NanoImprint templates with ultra-high vertical resolution and arbitrary distribution of heights were fabricated.•3D NanoImprint processes were developed based on 3D templates and investigation of potential NanoImprint methods and resists.•By implementing 3D NanoImprint, Fabry–Pérot-filter-array-based optical nanospectrometers were demonstrated. We report a novel 3D NanoImprint methodology with very high vertical resolution well below 1nm and a minimum surface roughness down to 0.2nm in root mean square (rms) which is attractive for several applications. We introduce our 3D NanoImprint methodology in fabricating 3D filter cavities of Fabry–Pérot filter arrays for optical nanospectrometers. A large number of different cavity heights can be fabricated in one single imprint step using this high resolution, low-cost 3D NanoImprint technology. The key issue of developing 3D NanoImprint technology is the fabrication of high resolution templates. The novel 3D templates contain arrays of negative or positive checkerboard-like mesa structures with currently up to 64 different heights. Different types of 3D templates were developed and adapted to cutting edge NanoImprint methods and imprint resists. The performance of different 3D NanoImprint recipes was investigated. Based on the novel 3D NanoImprint technology developed in this work, static Fabry–Pérot filter arrays with NanoImprinted cavities indicated rather high filter transmission (best single filter >90%), small line widths (about 2nm in full width at half maximum) and broad stop bands.