title: Diffraction-limited performance of flat-substrate reflective imaging gratings patterned by DUV photolithography.
abstract: We report on the first demonstration of flat substrate imaging gratings fabricated by deep ultraviolet (DUV) photoreduction lithography, which uniquely offers sub-100-nm resolution and spatial coherence over centimeter scales. Reflective focusing gratings, designed according to holographic principle, were fabricated on 300-mm silicon wafers by immersion DUV lithography. Spatial coherence of the fabrication process is evident in measured diffraction-limited imaging function. Flat-substrate gratings, with lines of arbitrary spacing and curvature, offer both dispersion and general spatial wavefront transformation combining the function of multiple optical elements. Fabrication at the sub-100-nm resolution level allows high-line-count, low-order efficient gratings even into the deep ultraviolet region. Nanoreplication of gratings at the wafer level provides a pathway to devices of ultimate low cost.
authors.forename: Christoph M
authors.initials: CM
authors.lastname: Greiner
authors.forename: D
authors.initials: D
authors.lastname: Iazikov
authors.forename: T W
authors.initials: TW
authors.lastname: Mossberg