Motion control platform for accurate measurement and manufacturing of nanostructures

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Motion control platform for accurate measurement
and manufacturing of nano-structures

• Hua Yang and Richard Seugling
• Advisors
• Dr. Stuart Smith
• Dr. Robert Hocken
• Dr. David Trumper

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Project Info.

• New project funded by NSF
• Award DMI-0210543
• 3 year project.
• Collaborative work UNC-Charlotte, NIST and MIT.

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Overview

• Motivation
• Project objectives
• Requirements
• Key components
• Conceptual designs
• Bearing system
• Drive system
• Immediate goals

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Motivation

• To facilitate the transition from nano-science to
  productive nanotechnology.
• To provide a means for pick and place at
  nanometer levels.
• To assess comparable designs at PTB, Eindhoven,
  and NPL.

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Objectives

• Development of integrated position measurement
  system with nanometer uncertainties traceable to
  national standards.
• Translation mechanism for multi degree-of-freedom
  motion control.
• Integration of fine motion controllers into
  long-range instrumentation for nano-scale
  manipulation in centimeter-sized workspaces.
• Integration of combined uncertainty analyses for
  determination of system error budget.
• Integration of cascaded multi degree-of-freedom
  control systems.

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Requirements

• Vacuum Compatibility
• 10-3 to 10-4 Torr
• Range
• 50 mm ? 50 mm ? 10 mm
• Velocity
• 5 mm/sec max velocity
• Resolution
• 25 nm positioning
• 10 nm accuracy

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Key Components

• Mechanical systems (UNCC)
• Vacuum chamber
• Precision translation stage
• Coarse/Fine stage
• Optical system (UNCC/NIST)
• Laser interferometer
• Lawall, J., Pedulla, J. M. and Coq, Y.L., 2001
  Ultrastable laser array at 633 nm for real-time
  dimensional metrology, Rev. Sci. Instrum., 72
  (7), pg. 2879-2888.
• Lawall, J. and Kessler, E., 2000, Michelson
  interferometry with 10 pm accuracy, Rev. Sci.
  Instrum., 71 (7), pg. 2669-2676.
• Control system (UNCC/MIT)
• DSP based cascading multi-degree-of freedom
  (MDOF) controller

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Vacuum chamber

• 304 stainless steel
• ID 44 inches
• Height gt 24 inches
• Two stage isolation
• external isolation
• internal isolation
• Multiple access ports
• Maglev turbo pump with roughing pump

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Conceptual designs of translation stage

• Fine motion stage Richard Seugling
• Coarse stage for long range motion
• Stacked coarse/fine stage possibilities
• Hockey Puck
• Stacked slide
• Double C

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Puck design

• FMS is dropped inside ball/feed screw coarse
  stage

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Stacked slide
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Double C

• Sunk between sets of guide -rails

FMS
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Bearing system

• Possible bearing system
• UHMWPE polymer slideway bearings
• Air bearings (Vacuum compatibility?)
• Roller bearings

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Polymer bearing assessment
UHMWPE bearing
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Noise test rig
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Vacuum test facility
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Drive system

• Possible drive system
• DC motor ball/feed screw
• Linear motors
• Voice coils

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Immediate goals (near future)

• Vacuum system procurement
• Optical systems specification and component
  identification
• Verify polymer bearing performance and vacuum
  compatibility
• Choice of design strategy for coarse stage
• Identification of calibration methodology and
  comparative assessment with competing systems

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Questions?Comments?Suggestion?