EUV mirror and optical system comprising EUV mirror

• Main Authors: Paul Hans-Jochen, Schicketanz Thomas, Zaczek Christoph
• Format: Patent
• Language: English
• Published: 13.03.2018
• Subjects: ACCESSORIES THEREFOR; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USINGWAVES OTHER THAN OPTICAL WAVES; APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FORPROJECTING OR VIEWING THEM; APPARATUS SPECIALLY ADAPTED THEREFOR; CINEMATOGRAPHY; ELECTROGRAPHY; GAMMA RAY OR X-RAY MICROSCOPES; HOLOGRAPHY; IRRADIATION DEVICES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES; MATERIALS THEREFOR; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; NANOTECHNOLOGY; NUCLEAR ENGINEERING; NUCLEAR PHYSICS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; ORIGINALS THEREFOR; PERFORMING OPERATIONS; PHOTOGRAPHY; PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES,e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTORDEVICES; PHYSICS; SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOTOTHERWISE PROVIDED FOR; TRANSPORTING

An EUV mirror with a substrate and a multilayer arrangement including: a periodic first layer group having N1>1 first layer pairs of period thickness P1 and arranged on a radiation entrance side of the multilayer arrangement; a periodic second layer group having N2>1 second layer pairs of period thickness P2 and arranged between the first layer group and the substrate; and a third layer group having N3 third layer pairs arranged between the first and second layer groups. N1>N2. The third layer group has a third period thickness P3 which deviates from an average period thickness PM=(P1+P2)/2 by a period thickness difference ΔP. ΔP corresponds to the quotient of the optical layer thickness (λ/4) of a quarter-wave layer and the product of N3 and cos(AOIM), AOIM being the mean incidence angle for which the multilayer arrangement is designed.