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Applications that require high resolution patterns are numerous, leading to an increasing demand for compact patterning tools and alternative lithographic concepts. For many scientific applications like biosensing or fabrication of metamaterials, or artificial crystals, the achievable resolution and the patterned area of the fabrication process are of main importance. In the field of high-volume manufacturing, there is a need for high-resolution patterning at the industrial exposure wavelength of 13.5 nm. The main industrial application for compact exposure tools is EUV photoresist development and its related process optimization. The overall patterned area is of minor interest. Instead, the focus is placed on the achievable resolution and quality of the intensity distribution used for the patterning tests. The realized EUV dual beamline allows to address both application fields in a single in-lab setup. By operating the source with an argon/xenon (Ar/Xe) gas mixture, a narrowband spectrum with a main wavelength of 10.9 nm is created without the need of spectral filtering. The resulting intensity of up to 2 mW/cm2 in wafer plane allows large area patterning with highest throughput of several mm2/min. Single exposure fields of 2 x 2 mm2 can be stitched together to achieve an overall patterned area of up to several cm² with minimal stitching borders of ~ 1 μm. By inserting a customized multilayer mirror into the beamline, the emission spectrum of the DPP source (operated with pure Xe gas) is in-band filtered to 13.5 nm, thus allowing qualification of industrial photoresists regarding sensitivity, contrast and resolution. The mask-wafer positioning system for the 13.5 nm beamline is designed for maximum rigidity to minimize relative movements between the mask and wafer that would lower the achievable resolution. Multi-field resolution test masks are created in-house and are exposed in a parallel manner to determine the achievable resist resolution in an efficient manner. Transmission mask designs are optimized by a rigorous simulation model. By tuning the pattern geometry on mask, different patterns like contact holes or nanopillars can be created on the wafer, tailored to the required application.
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