Share Email Print

Proceedings Paper

Multilayer reflective coatings for extreme-ultraviolet lithography
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Multilayer mirror coatings which reflect extreme UV (EUV) radiation are a key enabling technology for EUV lithography. So/Si multilayers with reflectances of 67.5 percent at 13.4 nm are now routinely achieved and reflectances of 70.2 percent at 11.4 nm were obtained with Mo/Be multilayers. High reflectance is achieved with careful control of substrate quality, layer thicknesses, multilayer materials, interface quality, and surface termination. Reflectance and film stress were found to be stable relative to the requirements for application to EUV lithography. The run-to- run reproducibility of the reflectance peak position was characterized to be better than 0.2 percent, providing the required wavelength matching among the seven multilayer- coated mirrors used in the present lithography system design. Uniformity of coating was improved to better than 0.5 percent across 150 mm diameter substrates. These improvements in EUV multilayer mirror technology will enable us to meet the stringent specifications for coating the large optical substrates for our next-generation EUV lithography system.

Paper Details

Date Published: 5 June 1998
PDF: 10 pages
Proc. SPIE 3331, Emerging Lithographic Technologies II, (5 June 1998); doi: 10.1117/12.309600
Show Author Affiliations
Claude Montcalm, Lawrence Livermore National Lab. (United States)
Sasa Bajt, Lawrence Livermore National Lab. (United States)
Paul B. Mirkarimi, Lawrence Livermore National Lab. (United States)
Eberhard Adolf Spiller, Lawrence Livermore National Lab. (United States)
Frank J. Weber, Lawrence Livermore National Lab. (United States)
James A. Folta, Lawrence Livermore National Lab. (United States)

Published in SPIE Proceedings Vol. 3331:
Emerging Lithographic Technologies II
Yuli Vladimirsky, Editor(s)

© SPIE. Terms of Use
Back to Top