Phase measurements of EUV mask defects
Abstract
Extreme Ultraviolet (EUV) Lithography mask defects were examined on the actinic mask imaging system, SHARP, at Lawrence Berkeley National Laboratory. Also, a quantitative phase retrieval algorithm based on the Weak Object Transfer Function was applied to the measured through-focus aerial images to examine the amplitude and phase of the defects. The accuracy of the algorithm was demonstrated by comparing the results of measurements using a phase contrast zone plate and a standard zone plate. Using partially coherent illumination to measure frequencies that would otherwise fall outside the numerical aperture (NA), it was shown that some defects are smaller than the conventional resolution of the microscope. We found that the programmed defects of various sizes were measured and shown to have both an amplitude and a phase component that the algorithm is able to recover.
- Authors:
-
- Univ. of California, Berkeley, CA (United States)
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Publication Date:
- Research Org.:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 1227885
- Report Number(s):
- LBNL-176093
Journal ID: ISSN 0091-3286; ir:176093
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Optical Engineering
- Additional Journal Information:
- Journal Volume: 9422; Journal ID: ISSN 0091-3286
- Publisher:
- SPIE
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 42 ENGINEERING; extreme ultraviolet; phase measurement; zone plates; apertures; phase retrieval; imaging systems; lithography; microscopes; phase contrast
Citation Formats
Claus, Rene A., Wang, Yow-Gwo, Wojdyla, Antoine, Benk, Markus P., Goldberg, Kenneth A., Neureuther, Andrew R., Naulleau, Patrick P., and Waller, Laura. Phase measurements of EUV mask defects. United States: N. p., 2015.
Web. doi:10.1117/12.2087195.
Claus, Rene A., Wang, Yow-Gwo, Wojdyla, Antoine, Benk, Markus P., Goldberg, Kenneth A., Neureuther, Andrew R., Naulleau, Patrick P., & Waller, Laura. Phase measurements of EUV mask defects. United States. https://doi.org/10.1117/12.2087195
Claus, Rene A., Wang, Yow-Gwo, Wojdyla, Antoine, Benk, Markus P., Goldberg, Kenneth A., Neureuther, Andrew R., Naulleau, Patrick P., and Waller, Laura. Sun .
"Phase measurements of EUV mask defects". United States. https://doi.org/10.1117/12.2087195. https://www.osti.gov/servlets/purl/1227885.
@article{osti_1227885,
title = {Phase measurements of EUV mask defects},
author = {Claus, Rene A. and Wang, Yow-Gwo and Wojdyla, Antoine and Benk, Markus P. and Goldberg, Kenneth A. and Neureuther, Andrew R. and Naulleau, Patrick P. and Waller, Laura},
abstractNote = {Extreme Ultraviolet (EUV) Lithography mask defects were examined on the actinic mask imaging system, SHARP, at Lawrence Berkeley National Laboratory. Also, a quantitative phase retrieval algorithm based on the Weak Object Transfer Function was applied to the measured through-focus aerial images to examine the amplitude and phase of the defects. The accuracy of the algorithm was demonstrated by comparing the results of measurements using a phase contrast zone plate and a standard zone plate. Using partially coherent illumination to measure frequencies that would otherwise fall outside the numerical aperture (NA), it was shown that some defects are smaller than the conventional resolution of the microscope. We found that the programmed defects of various sizes were measured and shown to have both an amplitude and a phase component that the algorithm is able to recover.},
doi = {10.1117/12.2087195},
journal = {Optical Engineering},
number = ,
volume = 9422,
place = {United States},
year = {Sun Feb 22 00:00:00 EST 2015},
month = {Sun Feb 22 00:00:00 EST 2015}
}
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