In order to forecast and warn of space weather, the disturbances of solar-terrestrial need to be monitored. Extreme Ultraviolet (EUV) filters can remove unwanted radiation, and they are an important part of the Extreme Ultraviolet Imager. In order to optimize the transmission of EUV filters at 17.1nm, we chosen the material and thickness of EUV filters at 17.1nm based on the Lambert-Beer law by theoretical calculation and software simulation. First, the release layer and metal thin-film were deposited by thermal evaporation, and EUV filters with nickel-mesh supported were successfully manufactured. After testing, the transmission of the filter whose surface is smooth and flat without obvious pinholes is about 43.81% at 17.1nm. Next, in order to illustrate the effect of the oxide layer on the transmittance, the filter sample was measured by spectroscopic ellipsometry to obtain the thickness of the oxide layer at different placement times, and the roughness was measured to optimize and simulate the transmission of the filter. The thickness of the oxide layer and the roughness of the sample were fitted by IMD, and the layer thickness was adjusted to achieve the curve closest to the actual measured value. Experimental results indicate an excellent agreement between the measured and simulated values, and the absolute error of the transmittance of the EUV filter is only 1%. This study provides preparation methods and improvement ideas for EUV filters, and has important practical significance in space exploration.
MAO J B , WANG P H , WANG J Y , et al . Detection of solar blind ultraviolet communication based on fluorescent wavelength conversion [J]. Opt. Precision Eng. , 2021 , 29 ( 10 ): 2296 - 2305 . (in Chinese) . doi: 10.37188/OPE.2021.0277 http://dx.doi.org/10.37188/OPE.2021.0277
YANG SH . Study on the Thermal Control Technique of Primary Mirror and Detector of Space Ultraviolet Solar Telescope [D]. Beijing : Institute of Physics, Chinese Academy of Sciences , 2021 . (in Chinese)
QI R Z , ZHANG J L , WU J L , et al . Thin film optical elements in extreme ultraviolet and vacuum ultraviolet [J]. Acta Optica Sinica , 2022 , 42 ( 11 ): 48 - 58 . (in Chinese)
BOERNER P , EDWARDS C , LEMEN J , et al . Initial Calibration of the Atmospheric Imaging Assembly ( AIA ) on the Solar Dynamics Observatory ( SDO ) [M]. The Solar Dynamics Observatory . New York, NY : Springer US , 2011 : 41 - 66 .
FU L X , WU Y G , WU H Y , et al . Fabrication and characterization of 30.4 nm Cr/Al/Cr self-supporting filters [J]. High Power Laser and Particle Beams , 2009 , 21 ( 2 ): 235 - 239 . (in Chinese)
WU H Y , WU Y G , LÜ G , et al . Preparation and characterization of free-standing polyimide/Zr film [J]. High Power Laser and Particle Beams , 2011 , 23 ( 4 ): 981 - 984 . (in Chinese)
WANG L H , HE L P , WANG X K , et al . 30.4 nm filter in normal incidence imager [J]. Opt. Precision Eng. , 2008 , 16 ( 1 ): 42 - 47 . (in Chinese)
ATTWOOD D T . Soft x-rays and extreme ultraviolet radiation: principles and applications [M]. Cambridge : Cambridge University Press , 2000 . doi: 10.1017/cbo9781139164429 http://dx.doi.org/10.1017/cbo9781139164429
TARRIO C , BERG R F , LUCATORTO T B , et al . Note: Thermally stable thin-film filters for high-power extreme-ultraviolet applications [J]. Review of Scientific Instruments , 2015 , 86 ( 11 ): 116103 .
HILL S B , FARADZHEV N S , RICHTER L J , et al . Optics contamination studies in support of high-throughput EUV lithography tools [C]. SPIE Advanced Lithography. Proc SPIE 7969 , Extreme Ultraviolet (EUV) Lithography II, San Jose, California, USA . 2011 , 7969 : 202 - 213 .
WINDT D L . IMD—Software for modeling the optical properties of multilayer films [J]. Computers in Physics , 1998 , 12 ( 4 ): 360 - 370 .
SCHMIDT J , KOLACEK K , FROLOV A , et al . Long-term changes in Al thin-film extreme ultraviolet filters [J]. Applied Optics , 2021 , 60 ( 28 ): 8766 - 8773 .
WANG ZH SH , MA Y Y , ZHANG J P , et al . The filters for a 18.2 nm normal-incidence microscopic imaging system [J]. Chinese Journal of Vacuum Science and Technology , 1997 , 17 ( 1 ): 12 - 18 . (in Chinese)
ZHANG L , WU Y G , CAO H , et al . Preparation and research of free-standing Zr filter for soft X-ray laser [J]. High Power Laser and Particle Beams , 2006 , 18 ( 6 ): 953 - 956 . (in Chinese)
GAO F J , ZHENG R T , CHENG G A . Research progress in preparation of self-supporting thin film [J]. Materials Review , 2007 , 21 ( 6 ): 1 - 3, 8 . (in Chinese) . doi: 10.3321/j.issn:1005-023X.2007.06.001 http://dx.doi.org/10.3321/j.issn:1005-023X.2007.06.001
PAN Y G , LIN ZH W , WANG B , et al . Film thickness uniformity of deep ultraviolet large aperture aspheric mirror [J]. Chinese Optics , 2022 , 15 ( 4 ): 740 - 746 . (in Chinese)
DIDKOVSKY L , JUDGE D , WIEMAN S , et al . EUV SpectroPhotometer ( ESP ) in Extreme Ultraviolet Variability Experiment ( EVE ): Algorithms and Calibrations [M]. The Solar Dynamics Observatory . New York, NY : Springer US , 2009 : 179 - 205 .
KOLACEK K , FROLOV A , SCHMIDT J , et al . Aging of Al thin film extreme ultraviolet filters [C]. SPIE Optics + Optoelectronics. Proc SPIE 11035, Optics Damage and Materials Processing by EUV/X-Ray Radiation VII, Prague, Czech Republic . 2019 , 11035 : 67 - 72 .
LARRUQUERT J I , KESKI-KUHA R A M . Far ultraviolet optical properties of MgF 2 films deposited by ion-beam sputtering and their application as protective coatings for Al [J]. Optics Communications , 2003 , 215 ( 1/2/3 ): 93 - 99 .
PIAO H , MCINTYRE N S . Adventitious carbon growth on aluminium and gold-aluminium alloy surfaces [J]. Surface and Interface Analysis , 2002 , 33 ( 7 ): 591 - 594 .
Research progress of normal-incidence optical system at extreme ultraviolet (EUV) wavelength
Nanosecond extreme ultraviolet radiation damage on thin film mirrors
Ultra-precision machining and testing of reflector mirrors for extreme ultraviolet and X-ray
Design and fabrication of EUV broadband multilayer mirrors with discrete thicknesses
Related Author
WANG Zhanshan
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Related Institution
Institute of Precision Optical Engineering, MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai Frontiers Science Center of Digital Optics, Shanghai Professional Technical Service Platform for Full-Spectrum and High-Performance Optical Thin Film Devices and Applications, School of Physics Science and Engineering, Tongji University
Institute of Precision Optical Engineering, MOE Key Laboratory of Advanced Micro-Structured Materials, Shanghai Frontiers Science Center of Digital Optics, Shanghai Professional Technical Service Platform for Full-Spectrum and High-Performance Optical Thin Film Devices and Applications, School of Physics Science and Engineering, Tongji University
Sino-German College of Applied Sciences, Tongji University
Advanced Manufacturing Technology for Optical Systems Laboratory, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences
National Synchrotron Radiation Laboratory, University of Science and Technology of China