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Title: High-efficiency spectral purity filter for EUV lithography

Abstract

An asymmetric-cut multilayer diffracts EUV light. A multilayer cut at an angle has the same properties as a blazed grating, and has been demonstrated to have near-perfect performance. Instead of having to nano-fabricate a grating structure with imperfections no greater than several tens of nanometers, a thick multilayer is grown on a substrate and then cut at an inclined angle using coarse and inexpensive methods. Effective grating periods can be produced this way that are 10 to 100 times smaller than those produced today, and the diffraction efficiency of these asymmetric multilayers is higher than conventional gratings. Besides their ease of manufacture, the use of an asymmetric multilayer as a spectral purity filter does not require that the design of an EUV optical system be modified in any way, unlike the proposed use of blazed gratings for such systems.

Inventors:
 [1]
  1. Livermore, CA
Issue Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
908431
Patent Number(s):
7050237
Application Number:
10/862,127
Assignee:
The Regents of the University of California (Oakland, CA)
Patent Classifications (CPCs):
G - PHYSICS G03 - PHOTOGRAPHY G03F - PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES
B - PERFORMING OPERATIONS B82 - NANOTECHNOLOGY B82Y - SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES
DOE Contract Number:  
W-7405-ENG-48
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Chapman, Henry N. High-efficiency spectral purity filter for EUV lithography. United States: N. p., 2006. Web.
Chapman, Henry N. High-efficiency spectral purity filter for EUV lithography. United States.
Chapman, Henry N. Tue . "High-efficiency spectral purity filter for EUV lithography". United States. https://www.osti.gov/servlets/purl/908431.
@article{osti_908431,
title = {High-efficiency spectral purity filter for EUV lithography},
author = {Chapman, Henry N},
abstractNote = {An asymmetric-cut multilayer diffracts EUV light. A multilayer cut at an angle has the same properties as a blazed grating, and has been demonstrated to have near-perfect performance. Instead of having to nano-fabricate a grating structure with imperfections no greater than several tens of nanometers, a thick multilayer is grown on a substrate and then cut at an inclined angle using coarse and inexpensive methods. Effective grating periods can be produced this way that are 10 to 100 times smaller than those produced today, and the diffraction efficiency of these asymmetric multilayers is higher than conventional gratings. Besides their ease of manufacture, the use of an asymmetric multilayer as a spectral purity filter does not require that the design of an EUV optical system be modified in any way, unlike the proposed use of blazed gratings for such systems.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {2006},
month = {5}
}