Share Email Print

Proceedings Paper

Multilayer coating of 10X projection optics for extreme ultraviolet lithography
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Two new sets of projection optics for our prototype 10X reduction EUV lithography system were coated with Mo/Si multilayers. The coating thickness was graded across the optics by using shadow masks to ensure maximum throughput at all incidence angles in the camera. The overall deviation of the wavelength response across the clear aperture of each mirror is below 0.01 percent RMS. However, the wavelength mismatch between two optics coated in different runs is up to 0.07 nm. Nevertheless, this is till within the allowed tolerances, and the predicted optical throughput loss in the camera due to such wavelength mismatch is about 4 percent. EUV reflectances of 63-65 percent were measured around 13.40 nm for the secondary optics, which is in good agreement with the expected reflectance based on the substrate finish as measured with AFM.

Paper Details

Date Published: 25 June 1999
PDF: 7 pages
Proc. SPIE 3676, Emerging Lithographic Technologies III, (25 June 1999); doi: 10.1117/12.351157
Show Author Affiliations
Claude Montcalm, Lawrence Livermore National Lab. (United States)
Eberhard Adolf Spiller, Lawrence Livermore National Lab. (United States)
Marco Wedowski, Lawrence Livermore National Lab. (United States)
Eric M. Gullikson, Lawrence Berkeley National Lab. (United States)
James A. Folta, Lawrence Livermore National Lab. (United States)

Published in SPIE Proceedings Vol. 3676:
Emerging Lithographic Technologies III
Yuli Vladimirsky, Editor(s)

© SPIE. Terms of Use
Back to Top