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Title: Extreme ultraviolet mask roughness effects in high numerical aperture lithography

Abstract

Given the reflective nature of extreme ultraviolet lithography and its extremely short operational wavelength, roughness of the optical surfaces is of significant concern. In particular, roughness in the mask multilayer leads to image plane speckle and ultimately patterned line-edge or line-width variability in the imaging process. Here we consider the implications of this effect for future high numerical aperture (NA) systems that are assumed to require anamorphic magnification projection optics. The results show significant anisotropic behavior at high NA as well as a substantial increase in relative patterned line variability in the shadowed direction when comparing 0.55 NA to 0.33 NA, despite the assumption of an anamorphic magnification system. In conclusion, the shadowed-direction patterned line variability is 2× larger than for unshadowed lines, and the majority of the increase in variability occurs in the low frequency regime.

Authors:
 [1];  [2];  [3]
  1. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  2. Univ. of California, Berkeley, CA (United States)
  3. Panoramic Technology Inc., Burlingame, CA (United States)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
SC-22.2 USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division; USDOE
OSTI Identifier:
1466716
Alternate Identifier(s):
OSTI ID: 1423166
Grant/Contract Number:  
AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Applied Optics
Additional Journal Information:
Journal Volume: 57; Journal Issue: 7; Related Information: © 2018 Optical Society of America.; Journal ID: ISSN 1559-128X
Publisher:
Optical Society of America
Country of Publication:
United States
Language:
English
Subject:
47 OTHER INSTRUMENTATION; photolithography; ultraviolet; X-ray; soft X-rays; extreme ultraviolet (EUV)

Citation Formats

Naulleau, Patrick, Wang, Yow -Gwo, and Pistor, Tom. Extreme ultraviolet mask roughness effects in high numerical aperture lithography. United States: N. p., 2018. Web. doi:10.1364/AO.57.001724.
Naulleau, Patrick, Wang, Yow -Gwo, & Pistor, Tom. Extreme ultraviolet mask roughness effects in high numerical aperture lithography. United States. https://doi.org/10.1364/AO.57.001724
Naulleau, Patrick, Wang, Yow -Gwo, and Pistor, Tom. 2018. "Extreme ultraviolet mask roughness effects in high numerical aperture lithography". United States. https://doi.org/10.1364/AO.57.001724. https://www.osti.gov/servlets/purl/1466716.
@article{osti_1466716,
title = {Extreme ultraviolet mask roughness effects in high numerical aperture lithography},
author = {Naulleau, Patrick and Wang, Yow -Gwo and Pistor, Tom},
abstractNote = {Given the reflective nature of extreme ultraviolet lithography and its extremely short operational wavelength, roughness of the optical surfaces is of significant concern. In particular, roughness in the mask multilayer leads to image plane speckle and ultimately patterned line-edge or line-width variability in the imaging process. Here we consider the implications of this effect for future high numerical aperture (NA) systems that are assumed to require anamorphic magnification projection optics. The results show significant anisotropic behavior at high NA as well as a substantial increase in relative patterned line variability in the shadowed direction when comparing 0.55 NA to 0.33 NA, despite the assumption of an anamorphic magnification system. In conclusion, the shadowed-direction patterned line variability is 2× larger than for unshadowed lines, and the majority of the increase in variability occurs in the low frequency regime.},
doi = {10.1364/AO.57.001724},
url = {https://www.osti.gov/biblio/1466716}, journal = {Applied Optics},
issn = {1559-128X},
number = 7,
volume = 57,
place = {United States},
year = {Thu Mar 01 00:00:00 EST 2018},
month = {Thu Mar 01 00:00:00 EST 2018}
}

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Cited by: 5 works
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Works referenced in this record:

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