1. Thermal Micro-actuators for Out-of-plane Motion
Brian Patrick Trease
The University of Michigan
Department of Mechanical Engineering
Sandia National Laboratories (Albuquerque, NM)
Org – MEMS Device Technologies
Thomas Zipperian, Manager
James Allen, Technical Advisor
October 6, 2001
Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under contract DE-AC04-94AL85000.

2. In the next 15 minutes …. Motivation – Adaptive Optics Background
MEMS
Thermal Actuators
Prototype Testing
Modeling
New Designs

3. Adaptive Optics Uncorrected Corrected 250 kg/m2
Abberation correction required for optical systems
Abberations
Atmospheric Disturbances
Physical Imperfections
Uncorrected
Corrected
Applications
Telescopes
(on Earth and in space)
Laser Systems
Imagery and weapons
250 kg/m2

4. Basic Adaptive Optics System
Deformable Mirror
aberrated
wavefront
Micromirror Array
Control requires high displacement and high resolution
beam sampler
imaging
system
control
computer
wavefront sensor

5. Background Microactuators and MEMS Out-of-Plane Actuators:
Small features (1 mm)
IC Fabrication
Only 10 mm tall
Flat structures
Initially in-plane
SUMMiT VTM
Out-of-Plane Actuators:
Pop-up mirrors Bent beams

6. Thermal Actuators Bimaterial Single Material (In-Plane) + V -
Aluminum
Bimaterial
Single Material (In-Plane)
Steel + V -
Resistive Heating

7. Prototype Testing Promising Results! Probe Station Top View (SEM)
Microscope
Side View
Chip with devices
Promising Results!

8. VIDEO CLIP

9. -- Convenience vs. Accuracy --
Actuator Models
Analytical Model
Finite Element Analysis (FEA)
current T0 T1 T2 i
Computers solve complex structures by breaking them down into simple elements
Bending via Force Method
-- Convenience vs. Accuracy --

10. New Designs 0
(a)
(b)

11. The Future Fabrication Physical Testing Select and Modify Best Designs
SUMMiT VTM Process
Physical Testing
Validation and Modification of Models
Select and Modify Best Designs

12. The University of Michigan Compliant Systems Design Laboratory
Thank You!
Brian Patrick Trease
The University of Michigan
Compliant Systems Design Laboratory
Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company for the United States Department of Energy under Contract DE-AC04-94AL85000.