Ringfield lithographic camera

Patent · Wed Dec 31 23:00:00 EST 1997

OSTI ID:871832

Sweatt, William C ^[1]

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1. Albuquerque, NM

A projection lithography camera is presented with a wide ringfield optimized so as to make efficient use of extreme ultraviolet radiation from a large area radiation source (e.g., D.sub.source .apprxeq.0.5 mm). The camera comprises four aspheric mirrors optically arranged on a common axis of symmetry with an increased etendue for the camera system. The camera includes an aperture stop that is accessible through a plurality of partial aperture stops to synthesize the theoretical aperture stop. Radiation from a mask is focused to form a reduced image on a wafer, relative to the mask, by reflection from the four aspheric mirrors.

• Research Organization: SANDIA CORP
• DOE Contract Number: AC04-94AL85000
• Assignee: Sandia Corporation (Albuquerque, NM)
• Patent Number(s): US 5805365
• OSTI ID: 871832
• Country of Publication: United States
• Language: English

Related Subjects

/359/378/
accessible
aperture
apprxeq
arranged
aspheric
aspheric mirror
aspheric mirrors
axis
camera
camera comprises
common
common axis
comprises
efficient
etendue
extreme
extreme ultraviolet
focused
form
image
increased
lithographic
lithographic camera
lithography
lithography camera
mask
mirrors
optically
optimized
partial
plurality
projection
projection lithography
radiation
radiation source
reduced
reflection
relative
ringfield
source
stop
stops
symmetry
synthesize
theoretical
ultraviolet
ultraviolet radiation
wafer
wide