OSA's Digital Library

Optics Express

Optics Express

  • Editor: Martijn de Sterke
  • Vol. 16, Iss. 20 — Sep. 29, 2008
  • pp: 15343–15352

Three-dimensional characterization of extreme ultraviolet mask blank defects by interference contrast photoemission electron microscopy

Jingquan Lin, Nils Weber, Matthias Escher, Jochen Maul, Hak-Seung Han, Michael Merkel, Stefan Wurm, Gerd Schönhense, and Ulf Kleineberg  »View Author Affiliations

Optics Express, Vol. 16, Issue 20, pp. 15343-15352 (2008)

View Full Text Article

Enhanced HTML    Acrobat PDF (422 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



A photoemission electron microscope based on a new contrast mechanism “interference contrast” is applied to characterize extreme ultraviolet lithography mask blank defects. Inspection results show that positioning of interference destructive condition (node of standing wave field) on surface of multilayer in the local region of a phase defect is necessary to obtain best visibility of the defect on mask blank. A comparative experiment reveals superiority of the interference contrast photoemission electron microscope (Extreme UV illumination) over a topographic contrast one (UV illumination with Hg discharge lamp) in detecting extreme ultraviolet mask blank phase defects. A depth-resolved detection of a mask blank defect, either by measuring anti-node peak shift in the EUV-PEEM image under varying inspection wavelength condition or by counting interference fringes with a fixed illumination wavelength, is discussed.

© 2008 Optical Society of America

OCIS Codes
(110.0180) Imaging systems : Microscopy
(110.5220) Imaging systems : Photolithography

ToC Category:
Imaging Systems

Original Manuscript: May 19, 2008
Revised Manuscript: July 27, 2008
Manuscript Accepted: August 30, 2008
Published: September 15, 2008

Jingquan Lin, Nils Weber, Matthias Escher, Jochen Maul, Hak-Seung Han, Michael Merkel, Stefan Wurm, Gerd Schönhense, and Ulf Kleineberg, "Three-dimensional characterization of extreme ultraviolet mask blank defects by interference contrast photoemission electron microscopy," Opt. Express 16, 15343-15352 (2008)

Sort:  Author  |  Year  |  Journal  |  Reset  


  1. K. A. Goldberg, A. Barty, Y. Liu, P. Kearney, Y. Tezuka, T. Terasawa, J. Taylor, H. Han, and O. WoodII, "Actinic inspection of extreme ultraviolet programmed multilayer defects and cross-comparison measurements," J.Vac.Sci.Technol. B 24, 2824-2828 (2006).
  2. T. Liang, P. Sandez, G. Zhang, E. Shu, R. Nagpal, and A. Stivers, " Understand and reduction of defect on finished EUV mask," Proc. SPIE 5752, 654-662 (2005). [CrossRef]
  3. Y. Tezuka, M. Ito,T. Terasawa, and T. Tomie, "Actinic detection and signal characterization of multilayer defect on EUV mask blanks," Proc. SPIE 5567, 791-799 (2004). [CrossRef]
  4. K. Kinoshita, T. Haga, K. Hanamoto,T. Shohi, M. Endo, and T. Watanabe, "Actinic mask metrology for extreme ultraviolet lithography," J. Vac. Sci. Technol. B 22, 264-267 (2004).
  5. J. Lin, U. Neuhauesler, J. Slieh, and U. Kleinberg "Actinic extreme ultraviolet lithogrphy mask blank defect inspection by photoemission microscopy," J. Vac. Sci. Technol. B 24, 2631-2635 (2006).
  6. V. Farys, P. Schiavone, P. Polack, M. Idir, and V. Muffato, "Highly sensitive detection technology of buried defects in extreme ultraviolet masks using at-wavelength scanning dark-field microscopy," Appl. Phys. Lett. 87,024102 (2005). [CrossRef]
  7. A. Oelsner, O. Schmidt, M. Schicketanz, and G. Schönhense "Microspectroscopy and imaging using a delay line detector in time-of-flight photoemission microscopy," Rev. Sci. Instrum. 72, 3968-3974 (2001). [CrossRef]
  8. K. Siegrist, E. Williams, and V. Ballarotto, "Characterizing topography-induced contrast in photoelectron emission microscopy," J. Vac. Sci. Technol. A 21, 1098-1102 (2003).
  9. G. Schönhense, A. Oelsner, and O. Schmidt, "Time-of-flight photoemission electron microscopy-a new way to chemical surface analysis," Surf. Sci. 480, 180-187 (2001). [CrossRef]
  10. C. M. Schneider and G. Schönhense, "Investigating surface magnetism by means of photoexcitation electron emission microscopy," Rep. Prog. Phys. 65, 1785-1839 (2002). [CrossRef]
  11. G. Schönhense, U. Kleineberg, German patent DE 100 32 979 A1 (Jan.17, 2002).
  12. J. Lin, N. Weber, J. Maul, S. Hendel, K. Rott, M. Merkel, G. Schönhense, and U. Kleingerg, "At-wavelength inspection of sub-40nm defects in extreme ultraviolet lithography mask blank by photoemission electron microscopy," Opt. Lett. 32, 1875-1877 (2007). [CrossRef] [PubMed]
  13. D. L. Windt, "IMD-Software for modeling the optical properties of multilayer films," Comput. Phys. 12360-372 (1998). [CrossRef]
  14. D. T. Attwood, Soft X-ray and Extreme Ultraviolet Radiation: Principle and Application (Cambridge University Press, 2000).

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited