Reflective optical imaging system with balanced distortion

Patent · Fri Jan 01 00:00:00 EST 1999

OSTI ID:872615

Chapman, Henry N ^[1]; Hudyma, Russell M ^[2]; Shafer, David R ^[3]; Sweeney, Donald W ^[2]

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1. Sunol, CA
2. San Ramon, CA
3. Fairfield, CT

An optical system compatible with short wavelength (extreme ultraviolet) An optical system compatible with short wavelength (extreme ultraviolet) radiation comprising four reflective elements for projecting a mask image onto a substrate. The four optical elements comprise, in order from object to image, convex, concave, convex and concave mirrors. The optical system is particularly suited for step and scan lithography methods. The invention enables the use of larger slit dimensions associated with ring field scanning optics, improves wafer throughput and allows higher semiconductor device density. The inventive optical system is characterized by reduced dynamic distortion because the static distortion is balanced across the slit width.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• DOE Contract Number: W-7405-ENG-48
• Assignee: Regents of University of California (Oakland, CA)
• Patent Number(s): US 5973826
• OSTI ID: 872615
• Country of Publication: United States
• Language: English

Related Subjects

reflective
optical
imaging
balanced
distortion
compatible
wavelength
extreme
ultraviolet
radiation
comprising
elements
projecting
mask
image
substrate
comprise
convex
concave
mirrors
particularly
suited
step
scan
lithography
methods
enables
larger
slit
dimensions
associated
field
scanning
optics
improves
wafer
throughput
allows
semiconductor
device
density
inventive
characterized
reduced
dynamic
static
width
reflective elements
concave mirrors
mask image
scan lithography
lithography methods
reflective optical
optical imaging
particularly suited
optical element
optical elements
extreme ultraviolet
semiconductor device
concave mirror
radiation comprising
reduced dynamic
slit width
reflective element
static distortion
slit dimensions
scanning optics
device density
wafer throughput
dimensions associated
improves wafer
dynamic distortion
field scanning
elements comprise
balanced distortion
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