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Title: Method and apparatus for inspecting an EUV mask blank

Abstract

An apparatus and method for at-wavelength EUV mask-blank characterization for inspection of moderate and low spatial frequency coating uniformity using a synchrotron or other source of EUV light. The apparatus provides for rapid, non-destruction, non-contact, at-wavelength qualification of large mask areas, and can be self-calibrating or be calibrated to well-characterized reference samples. It can further check for spatial variation of mask reflectivity or for global differences among masks. The apparatus and method is particularly suited for inspection of coating uniformity and quality and can detect defects in the order of 50 .mu.m and above.

Inventors:
Publication Date:
Research Org.:
The Regents of the University of California, Oakland, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1175545
Patent Number(s):
6,963,395
Application Number:
09/902,502
Assignee:
The Regents of the University of California (Oakland, CA) OSTI
DOE Contract Number:
AC03-76SF00098
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
47 OTHER INSTRUMENTATION

Citation Formats

Goldberg, Kenneth A. Method and apparatus for inspecting an EUV mask blank. United States: N. p., 2005. Web.
Goldberg, Kenneth A. Method and apparatus for inspecting an EUV mask blank. United States.
Goldberg, Kenneth A. Tue . "Method and apparatus for inspecting an EUV mask blank". United States. doi:. https://www.osti.gov/servlets/purl/1175545.
@article{osti_1175545,
title = {Method and apparatus for inspecting an EUV mask blank},
author = {Goldberg, Kenneth A.},
abstractNote = {An apparatus and method for at-wavelength EUV mask-blank characterization for inspection of moderate and low spatial frequency coating uniformity using a synchrotron or other source of EUV light. The apparatus provides for rapid, non-destruction, non-contact, at-wavelength qualification of large mask areas, and can be self-calibrating or be calibrated to well-characterized reference samples. It can further check for spatial variation of mask reflectivity or for global differences among masks. The apparatus and method is particularly suited for inspection of coating uniformity and quality and can detect defects in the order of 50 .mu.m and above.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Nov 08 00:00:00 EST 2005},
month = {Tue Nov 08 00:00:00 EST 2005}
}

Patent:

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