Cleaning process for EUV optical substrates

Patent · 31 December 1998

OSTI ID:872534

Weber, Frank J ^[1]; Spiller, Eberhard A ^[2]

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1. Sunol, CA
2. Mt. Kiso, NY

A cleaning process for surfaces with very demanding cleanliness requirements, such as extreme-ultraviolet (EUV) optical substrates. Proper cleaning of optical substrates prior to applying reflective coatings thereon is very critical in the fabrication of the reflective optics used in EUV lithographic systems, for example. The cleaning process involves ultrasonic cleaning in acetone, methanol, and a pH neutral soap, such as FL-70, followed by rinsing in de-ionized water and drying with dry filtered nitrogen in conjunction with a spin-rinse.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA
• DOE Contract Number: W-7405-ENG-48
• Assignee: Regents of University of California (Oakland, CA)
• Patent Number(s): US 5958143
• OSTI ID: 872534
• Country of Publication: United States
• Language: English

Related Subjects

/134/427/
acetone
applying
cleaning
cleaning process
cleanliness
coatings
conjunction
critical
de-ionized
demanding
dry
drying
euv
euv optical
example
extreme-ultraviolet
fabrication
filtered
fl-70
followed
involves
lithographic
methanol
neutral
nitrogen
optical
optical substrate
optical substrates
optics
ph
prior
process
process involves
proper
reflective
reflective coating
reflective coatings
requirements
rinsing
soap
spin-rinse
substrates
surfaces
systems
thereon
ultrasonic
ultrasonic cleaning
water