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Title: High numerical aperture projection system for extreme ultraviolet projection lithography

Abstract

An optical system is described that is compatible with extreme ultraviolet radiation and comprises five reflective elements for projecting a mask image onto a substrate. The five optical elements are characterized in order from object to image as concave, convex, concave, convex, and concave mirrors. The optical system is particularly suited for ring field, step and scan lithography methods. The invention uses aspheric mirrors to minimize static distortion and balance the static distortion across the ring field width which effectively minimizes dynamic distortion. The present invention allows for higher device density because the optical system has improved resolution that results from the high numerical aperture, which is at least 0.14.

Inventors:
 [1]
  1. San Ramon, CA
Issue Date:
Research Org.:
Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
OSTI Identifier:
873028
Patent Number(s):
6072852
Assignee:
Regents of 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
G - PHYSICS G21 - NUCLEAR PHYSICS G21K - TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR
DOE Contract Number:  
W-7405-ENG-48
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
numerical; aperture; projection; extreme; ultraviolet; lithography; optical; described; compatible; radiation; comprises; five; reflective; elements; projecting; mask; image; substrate; characterized; concave; convex; mirrors; particularly; suited; field; step; scan; methods; aspheric; minimize; static; distortion; balance; width; effectively; minimizes; dynamic; allows; device; density; improved; resolution; results; 14; reflective elements; concave mirrors; mask image; scan lithography; lithography methods; projection lithography; numerical aperture; particularly suited; ultraviolet radiation; optical element; optical elements; extreme ultraviolet; concave mirror; reflective element; static distortion; device density; improved resolution; aspheric mirrors; aspheric mirror; dynamic distortion; /378/250/359/

Citation Formats

Hudyma, Russell M. High numerical aperture projection system for extreme ultraviolet projection lithography. United States: N. p., 2000. Web.
Hudyma, Russell M. High numerical aperture projection system for extreme ultraviolet projection lithography. United States.
Hudyma, Russell M. Sat . "High numerical aperture projection system for extreme ultraviolet projection lithography". United States. https://www.osti.gov/servlets/purl/873028.
@article{osti_873028,
title = {High numerical aperture projection system for extreme ultraviolet projection lithography},
author = {Hudyma, Russell M},
abstractNote = {An optical system is described that is compatible with extreme ultraviolet radiation and comprises five reflective elements for projecting a mask image onto a substrate. The five optical elements are characterized in order from object to image as concave, convex, concave, convex, and concave mirrors. The optical system is particularly suited for ring field, step and scan lithography methods. The invention uses aspheric mirrors to minimize static distortion and balance the static distortion across the ring field width which effectively minimizes dynamic distortion. The present invention allows for higher device density because the optical system has improved resolution that results from the high numerical aperture, which is at least 0.14.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Jan 01 00:00:00 EST 2000},
month = {Sat Jan 01 00:00:00 EST 2000}
}

Works referenced in this record:

Design of reflective relay for soft x-ray lithography
conference, January 1991


Reflective systems design study for soft x-ray projection lithography
journal, November 1990


Optical system design issues in development of projection camera for EUV lithography
conference, May 1995