Mark Tillack, John Pulsifer,

1
Final Optic Fabrication, Testing and System
Integration
Mark Tillack, John Pulsifer, Joel Hollingsworth,
S. S. Harilal
With contributions from Bill Goodman (Schafer
Corp.), Hesham Khater (LLNL), Colin Ophus and
Dave Mitlin (U. Alberta)
HAPL Project Meeting San Diego, CA 8-9 August 2006
2
Progress was made in 5 areas
2 of 13

• Improved our simulation capability
• A KrF oscillator-amplifier configuration was
  installed and tested
• Sample scanning and auto shutdown were added
• Expanded the database on Al coatings (toward
  end-of-life)
• More data were obtained on electroplated and
  e-coated mirrors
• Developed techniques to fabricate larger optics
• CMP was tested for post-processing large-area
  high-quality surfaces
• Performed component and system integration
• A substrate assessment was performed (Schafer)
• Neutron irradiation experiments were planned
• Explored alternative mirror concepts
• 4 AlMo mirrors were fabricated in collaboration
  w/ LBNL and U. Alberta

• Improved our simulation capability
• A KrF oscillator-amplifier configuration was
  installed and tested
• Sample scanning and auto shutdown were added
• Expanded the database on Al coatings (toward
  end-of-life)
• More data were obtained on electroplated and
  e-coated mirrors
• Developed techniques to fabricate larger optics
• CMP was tested for post-processing large-area
  high-quality surfaces
• Performed component and system integration
• A substrate assessment was performed (Schafer)
• Neutron irradiation experiments were planned
• Explored alternative mirror concepts
• 4 AlMo mirrors were fabricated in collaboration
  w/ LBNL and U. Alberta

• Improved our simulation capability
• A KrF oscillator-amplifier configuration was
  installed and tested
• Sample scanning and auto shutdown were added
• Expanded the database on Al coatings (toward
  end-of-life)
• More data were obtained on electroplated and
  e-coated mirrors
• Developed techniques to fabricate larger optics
• CMP was tested for post-processing large-area
  high-quality surfaces
• Performed component and system integration
• A substrate assessment was performed (Schafer)
• Neutron irradiation experiments were planned
• Explored alternative mirror concepts
• 4 AlMo mirrors were fabricated in collaboration
  w/ LBNL and U. Alberta

• Improved our simulation capability
• A KrF oscillator-amplifier configuration was
  installed and tested
• Sample scanning and auto shutdown were added
• Expanded the database on Al coatings (toward
  end-of-life)
• More data were obtained on electroplated and
  e-coated mirrors
• Developed techniques to fabricate larger optics
• CMP was tested for post-processing large-area
  high-quality surfaces
• Performed component and system integration
• A substrate assessment was performed (Schafer)
• Neutron irradiation experiments were planned
• Explored alternative mirror concepts
• 4 AlMo mirrors were fabricated in collaboration
  w/ LBNL and U. Alberta

• Improved our simulation capability
• A KrF oscillator-amplifier configuration was
  installed and tested
• Sample scanning and auto shutdown were added
• Expanded the database on Al coatings (toward
  end-of-life)
• More data were obtained on electroplated and
  e-coated mirrors
• Developed techniques to fabricate larger optics
• CMP was tested for post-processing large-area
  high-quality surfaces
• Performed component and system integration
• A substrate assessment was performed (Schafer)
• Neutron irradiation experiments were planned
• Explored alternative mirror concepts
• 4 AlMo mirrors were fabricated in collaboration
  w/ LBNL and U. Alberta

3
Control over beam characteristics required us to
add an amplifier
3 of 13
Death by 1000 cuts loss of energy in the
Pockels cell was the final straw
4
Good news and bad news
4 of 13
5
Facility improvements are making life easier, and
higher shot-counts possible
5 of 13
Automated shutdown enables higher PRF
No damage
Damage leading to shutdown
6
We have a lot more data now on diamond-turned
Alumiplate
6 of 13
Laser-induced damage testing of metal mirrors
fluence-life data and surface analysis J.
Pulsifer, M. S. Tillack, J. Hollingsworth, L.
Carlson
7
Grain size effects on pure Al are obscured by
variations in fabrication techniques
7 of 13

• Evaporative coating was attempted because smaller
  grains should result in a stronger surface (?y
  ?o ky/d1/2)
• All surfaces were diamond-turned
• Not all evaporative coatings have smaller grains,
  and the trend with grain size is not obvious
• Better control of fabrication processes is
  essential for continuation of this work

Schafer
Bach
Alumiplate
8
CMP provides us a pathway to high-quality,
large-aperture metal mirrors
8 of 13

• Uses a corrosive slurry with carefully passivated
  surface
• Significant advantages over SPDT
• Less invasive (thinner coatings)
• Time depends on depth, not area
• History of semiconductor-level QC

lt1 nm RMS, 15 nm pits
Cabot Microelectronics is supporting this work
with substantial IRD support
Fabrication techniques for Al and Al alloy
optical coatings for the GIMM J. Hollingsworth,
J. Pulsifer and M. S. Tillack
9
A new alloy, AlMo was explored as a high-strength
alternative to pure Al
9 of 13

• 2-gun magnetron sputtered
• Thick (gt5 ?m) specular coating obtained with no
  postprocessing
• Improved mechanical properties
• Reflectivity conductivity?

Amorphous/nano-crystalline regime
Hall-Petch and solid solution hardening regime
Acknowledgements Thanks to Tim Renk,
SNLA Velomir Radmilovic, LBNL Dave Mitlin, U.
Alberta Colin Ophus, U. Alberta
10
Al-16Mo and Al-24Mo were fabricated and tested
10 of 13

• Beautiful, specular thick film

11
Candidate substrates were evaluated in
preparation for radiation testing (1 cm) and
prototype (4) development
11 of 13
Candidates
Metrics

• Neutronic feasibility
• Neutron damage resistance
• Purity
• Manufacturability
• Surface figure
• Roughness
• Coating adhesion
• Cooling capability
• Industrial capability
• Available database
• RD needs (risk)
• Cost

• Carbon Based
• C-C composite
• Carbon fiber reinforced
• Silicon Carbide
• ?-SiC (polycrystalline)
• Reaction bonded SiC (2-phase, polycrystalline)
• ?-SiC (CVD, polycrystalline)
• ?-SiC foam core (CVD/CVI, polycrystalline)
• Silicon
• Silicon foam core (CVD/CVI, polycrystalline)
• Czochralski (single crystal)
• Aluminum Alloys
• AlBeMet 162
• Al 6061 foam

Candidate Mirror Technologies for the Grazing
Incidence Metal Mirror Bill Goodman (Schafer
Corp.)
12
Neutron irradiations are being planned
12 of 13

• A key issue for substrates is neutron-induced
  swelling
• We plan to test candidate substrates SiC, Si,
  AlBeMet, Al-6061
• Include Al coatings to measure neutron-induced
  roughness
• Measure surface shape and roughness after
  irradiations

Three 22-day cycles ? 5.4 FPY dose

• HFIR flux
• gt0.1 MeV 1015 n/cm2/s
• gt1 MeV 6x1014 n/cm2/s
• Power plant
• gt0.1 MeV 1013 n/cm2/s
• gt1 MeV 1013 n/cm2/s

13
Next-step goals for GIMM RD
13 of 13
Coating-substrate development Fabricate and
test Al on C/Si and Al/Be composites Continue
efforts on coating improvements Obtain 4
specimens from vendors Plan test campaigns at
Mercury and Electra End-of-life testing
Complete the facility improvements Perform
further studies of rep-rate effects Acquire
data to 108 shots Radiation damage testing
Finish planning Obtain specimens