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When x-rays are generated via SL (synchrotron light) with a storage ring, batch lithographic-based micromachining is possible of structures that cannot be fabricated with other processes. When such lithography is used with various material deposition processes, fabrication of new precision microstructures, components, and transducers is possible. SL emissions occur when radial acceleration of a charged particle takes place as the particle travels in a circular arc. For continuous generation of SL, a storage ring is used that is a vacuum chamber that stores extremely relativistic electrons or protons in a circular path for hours. To grab a segment of SL, a beamline is extended from the storage ring to transfer light to an end-station. There, the SL is used for x-ray lithographic exposure. At the end-station, an x-ray mask and substrate are scanned through the SL horizontal stripe to provide uniform exposure throughout the substrate area. X-rays generated from SL are in multiple ways the best light source for microstructure patterning, since the light has for all practical purposes no diffractive, reflective, or refractive effects since exposure occurs through atomic absorption. Topics covered include the two primary requirements needed to use the lithographic tool, photoresists that offer a different lithographic procedure (through enhancement of sensitivity over PMMA by much more than 100X), design latitude for process design rules with SL-based lithography, and a recent demonstration of batch fabrication of a substantial variety of multiple angled structures.
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