Mirror Metrology and Development Strategy

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Mirror Metrology and Development Strategy
Q. Shen, K. Kaznatcheev, A. Fluerasu Experimental
Facilities Division NSLS-II Experimental
Facilities Advisory Committee Meeting April
23-24, 2009
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Outline

• Mirror requirements at NSLS-II beamlines
• NSLS-II strategy for mirror development and
  metrology
• Optical metrology laboratory
• Coherence preserving optics RD
• Summary

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Mirrors Requirements at NSLS-II beamlines
CHX
IXS
lt150 nrad
lt100 nrad
lt0.17 mrad
CSX
SRX
lt0.2 mrad

• General requirements lt 0.1 mrad 1 nm / 1 cm

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Experimental Facilities RD Areas Budgets
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Recruitment of Optical Metrology Expert
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Trend in Mirror Fabrication
Courtesy of A. Rommeveaux, R. Barret, ESRF

• Steady improvement of the mirror quality, but not
  yet to 100nrad / 1nm level
• New fabrication technologies emerged APS
  (profile coating) Osaka/Spring-8 (plasma
  chemical vaporization machining (PCVM) elastic
  emission machining (EEM)? WinLight/ESRF
  (polishing of deformed surfaces) SESO (Bimorph,
  piezo embedded)?

• New fabrication/polishing tools often require
  extensive use of in-house optical metrology to
  allow iterations in the process.

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Mirror Development Strategy 1

• Develop NSLS-II metrology tools?
• Use our own metrology to characterize vendor
  product crucial for verification acceptance
• Leverage our state-of-the-art metrology
  capability to energize and attract developers and
  vendors
• At-wavelength metrology at existing sources,
  emphasis on coherence preservation

QED test sample (2008) flat Si Takacs
Siddons (BNL)
before 236nm (rms)?
? Residual texture due to the tool marks-gt need
to reduce roughness (to 1/10) at low spatial
frequencies
after MRF 10nm (rms)?
BUT
x 20 improvement
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Optical Metrology Laboratory

• NSLS-II Optical Metrology Lab plans to
  house/develop cutting-edge metrology tools for
  advanced optics development
• Fizeau interferometer
• Long Trace Profiler (LTP)
• Micro-stitching interferometer
• Atomic Force Microscope (AFM)
• At wavelength metrology

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OM First Set of Instruments
Specification ZYGO VeriFire Aperture Size 4 in.
(102 mm) Zoom Range 1X-6X continuous zoom Pupil
Focus Range -800 mm/ 1600 mm Repeatability of
Three-Flat Test ?/300 (2s)2nm Repeatability of
rms ?/10,000 (2s)0.06nm Spatial Sampling1K x 1K
pixel camera Surface Height Resolution Better
than ?/8,000 0.1nm Reference Optics Dynaflex
(high reflectivity) 4 flat l/20 accuracy 4
transmission l/50 accuracy matching
cavity Backreflection corner cube
Status installed FollowUp development of
precise stage (meridional direction, 50nrad) for
stitching measurement of curved surfaces
Specification Motorized Tip/Tilt/X/Y with 4
300/300mm Vibration Isolation Table Objectives
2.5X, 20X (5 to 0.2mm FoV) Lateral Res. 0.5
µm Vertical Scan Range (PZT) 150 µm Vertical Res.
lt 0.1 nm RMS Repeatability lt 0.01 nm
Status NewView 6300 was upgraded with 300mm XY
motorized stages to perform stitching
interferometry
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Next Generation LTP Development
Takacs, P.Z., Qian, S., (BNL) LTP-I
1987 LTP-II CRADA with Continental Optics, RD
award 1993 Pentaprizm based LTP 1995 In-situ
mLTP by 2005 about 10 in all major SR
centers Currently aproches 0.35urad performance
Participants of Advanced Optical Systems and
Metrology for High Power and Coherent Beam Lines
Workshop during NSLS 2004 user meeting
Goal to reach 100 nrad accuracy for large radius
SR mirrors (/-10mrad)
Qian, OptEngineering 2007
gt In house international expert advisory team
for LTP development
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Optics Testing at SR
B-fiber
ID6 undulator
DCM Si-111
HR X-ray CCD-camera
Test Optics
Direct beam Multilayer

• Coherence preservation by multilayers
• O. Tchoubar, A. Snigirev, A. Fluerasu et al.
  Theoretical work on phase retrieval from in-line
  holograms. Aim retrieve the surface profile,
  power spectral density function
• Experimental work at ESRF ID6 (but also get RD
  NSLS x16 beamline operational)
• Mirror Fabrication/ Multilayer Deposition
  R.Conley

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Mirror Development Strategy 2

• Work/Collaborate with potential vendors
• Survey vendors and their current state-of-the-art
  technologies, organize on-site presentations and
  discussions, ... (QED visit Feb.2009, InSync
  Apr.2009, Zeiss- May)
• Spell out NSLSII requirements
• Seek potential collaborations, leverage NSLSII
  state of the art metrology and x-ray testing
  capability to energize and attract developers and
  vendors aimed at improving their technologies
  towards reaching our goals
• Proceed with tests and development
• Goal identify 2-3 reliable vendors by mid-FY11
  for procurements of NSLS-II mirrors to spec and
  on schedule
• Long-term vision
• Aimed at developing novel polishing techniques
  (not only with vendors, but university..),
  advanced metrology tools and new approach to
  state of the art x-ray optics (RD adaptive
  optics, mirror cryo-cooling, novel optics
  (diamond CRL))
• Establish a regional center for advanced mirror
  technology, involving BNL, upstate research
  universities, and regional optics manufacturers
  and vendors

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Summary

• NSLS-II plan for mirror metrology and mirror
  development is in place and being executed
• Recruitment is on-going for an optical metrology
  expert to lead the effort
• Optical metrology laboratory is being established
  as part of experimental facilities RD program
• Metrology instruments are being procured and some
  have already been installed and ready for use
• Remaining key instrument is the next generation
  LTP that is planned to be developed in the coming
  year
• Strategy on working with potential vendors is in
  place
• Goal to identify and qualify 2-3 reliable
  vendors by mid-FY11 so that NSLS-II mirror
  procurement can proceed at spec and on schedule