1 BROOKHAVEN SCIENCE ASSOCIATES Nanopositioning R&D Plan Yong Chu Experimental Facilities Division, NSLS-II Experimental Facilities Advisory Committee Meeting April 23-24, 2009

2 BROOKHAVEN SCIENCE ASSOCIATES HXN Team HXN beamline Yong Chu: Group Leader (Joined Jan. 2009) Beamline Scientist: Getting near making decision to hire Ken Evans-Lutterodt (MOU Staff, Kinoform development, lead initial HXN effort ) Nanopositioning R&D Engineer: Interviewing 1 nm R&D Hanfei Yan (MLL theory, optics testing) Enju Lima (coherent phase retrieval, optics testing) Ray Conley (MLL fabrication, metrology) Nathalie Bouet (postdoc, MLL processing) James Biancarosa (technician, MLL fabrication)

3 BROOKHAVEN SCIENCE ASSOCIATES Technical Challenges Focusing optics - fabrication of large (>100  m), wedged MLLs - thinning MLLs for x-ray energies at 10 keV or lower - bonding two MLLs into a monolitic optic - wedged MLLs are extremely chromatic X-ray Microscope - sub-nanometer positioning /scanning - sub-nanometer stability - small working distance ( < 1 mm) - integrated XRF detector with maximum solid angle - implementation of in situ controls or sample environments End-Station - vibration, temperature, air-flow, acoustic management Beamline optics - large coherence length at focusing optics - angular stability of 1  rad or better - preservation of uniform wave front

4 BROOKHAVEN SCIENCE ASSOCIATES Schematic of the Overall Design Strategy for 1nm Satellite bldg. Thick concrete slab structural filtering:  z < 20nm Conventional natural site vibration:  z < 25nm Specially engineered granite support with no vibration amplification:  z<20nm Active damping /isolation table:  z~2-4nm Low-profile low thermal expansion stages with active feedback:  z~0.2nm Temperature stability in mini-closure:  T < 0.05 o C overall, < 0.01 o C relative (bewteen optic & sample) Granite block Satellite bldg. wall on separate footing Engineered structures to compensate for measured floor vibration Hutch wall In-hutch  T ~ 0.1 o C 1nm focus

5 BROOKHAVEN SCIENCE ASSOCIATES Considerations for Nanopositioning Actuator - piezoelectric with moderate travel distance Guidance/Carrier - avoid bearings, sliders, screws, gear-reducer, etc - flexure-based motion for higher stiffness. Sensors - feedback on the “combined” motion  Laser Doppler Linear Encoder - require low noise enabling high res. Control - high speed/bandwidth - need capability for “fly scan” Environment - suppression of low frequency vibration - temp. stability to prevent drift Deming Shu’s Prototype Linear Flexure 2 mm travel range + 4  rad tilt error Resolution test of the one-dimensional laser Doppler linear actuator closed-loop control system by Deming Shu (APS)

6 BROOKHAVEN SCIENCE ASSOCIATES Nanopositioning R&D Plan In collaboration with the APS: Develop a long travel (~3mm), high-stiffness, flexure-based xyz linear stages with laser encoding resolution of sub-nanometer. Develop a long range (~10°), high-stiffness, flexure-based  rotary stage. - use high mechanical repeatability to build a look-up table to correct run-out and wobble errors. Develop MLL positioner, meeting the HXN requirements (the experience from the CNM/APS MLL instrument will be very helpful). Construct a HXN prototype (in air or He) combining the above components by FY2011-Q4. Develop vibration damping solutions for the HXN support frame/table.

7 BROOKHAVEN SCIENCE ASSOCIATES HXN microscope The microscope design will be guided by the experience with the HXN prototype. Require differential laser encoding between the sample and the MLL optics. In vacuum for thermal stability. Integration of XRF detector. Require 0.2~0.5 nm stability. Work with a vender for construction

8 BROOKHAVEN SCIENCE ASSOCIATES FY2009 FY2010 FY2011 FY2012 FY2013 FY2014 FY2015 HXN Time Line Prototype-I Experiment at CNM/APS Wedged MLL available Testing Prototype-I at APS or other SRs Prototype-II Design Experiment at HXN Prototype-II construction Build up NSLS-II Nanopositioning Lab: Research Vibration Damping for the HXN table

9 BROOKHAVEN SCIENCE ASSOCIATES Summary Nanopositioning R&D will be focused on developing high-stiffness, flexure- based xyz linear stages and a rotary stage with long travel (~3mm + ~10°) in collaboration with the APS HXN prototype is planned to be constructed by FY2011-Q4. HXN prototype will enable: - testing of MLLs - investigating methods to bond two MLLs - identifying specific engineering/technical challenges required for the HXN microscope