Method and apparatus for inspecting reflection masks for defects
Abstract
An at-wavelength system for extreme ultraviolet lithography mask blank defect detection is provided. When a focused beam of wavelength 13 nm is incident on a defective region of a mask blank, three possible phenomena can occur. The defect will induce an intensity reduction in the specularly reflected beam, scatter incoming photons into an off-specular direction, and change the amplitude and phase of the electric field at the surface which can be monitored through the change in the photoemission current. The magnitude of these changes will depend on the incident beam size, and the nature, extent and size of the defect. Inspection of the mask blank is performed by scanning the mask blank with 13 nm light focused to a spot a few .mu.m in diameter, while measuring the reflected beam intensity (bright field detection), the scattered beam intensity (dark-field detection) and/or the change in the photoemission current.
- Inventors:
-
- Oakland, CA
- Berkeley, CA
- Issue Date:
- Research Org.:
- Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 921275
- Patent Number(s):
- 6555828
- Application Number:
- 09/193,198
- Assignee:
- The Regents of the University of California (Oakland, CA)
- Patent Classifications (CPCs):
-
G - PHYSICS G01 - MEASURING G01N - INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
G - PHYSICS G03 - PHOTOGRAPHY G03F - PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES
- DOE Contract Number:
- AC03-76SF00098
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
Citation Formats
Bokor, Jeffrey, and Lin, Yun. Method and apparatus for inspecting reflection masks for defects. United States: N. p., 2003.
Web.
Bokor, Jeffrey, & Lin, Yun. Method and apparatus for inspecting reflection masks for defects. United States.
Bokor, Jeffrey, and Lin, Yun. Tue .
"Method and apparatus for inspecting reflection masks for defects". United States. https://www.osti.gov/servlets/purl/921275.
@article{osti_921275,
title = {Method and apparatus for inspecting reflection masks for defects},
author = {Bokor, Jeffrey and Lin, Yun},
abstractNote = {An at-wavelength system for extreme ultraviolet lithography mask blank defect detection is provided. When a focused beam of wavelength 13 nm is incident on a defective region of a mask blank, three possible phenomena can occur. The defect will induce an intensity reduction in the specularly reflected beam, scatter incoming photons into an off-specular direction, and change the amplitude and phase of the electric field at the surface which can be monitored through the change in the photoemission current. The magnitude of these changes will depend on the incident beam size, and the nature, extent and size of the defect. Inspection of the mask blank is performed by scanning the mask blank with 13 nm light focused to a spot a few .mu.m in diameter, while measuring the reflected beam intensity (bright field detection), the scattered beam intensity (dark-field detection) and/or the change in the photoemission current.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Apr 29 00:00:00 EDT 2003},
month = {Tue Apr 29 00:00:00 EDT 2003}
}
Works referenced in this record:
Minimum critical defects in extreme-ultraviolet lithography masks
journal, November 1997
- Lin, Yun
- Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, Vol. 15, Issue 6