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An Overview of the PRISM CenterMatthew PotrawskiManaging
Director
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Overview
Led by Dr. Jayathi MurthyRobert V. Adams Professorof Mechanical
Engineering
Newly-funded by DOEs National Nuclear SecurityAdministration
(NNSA)
$21.2M for 5 years
UIUC, UNM, and Vanderbilt as partners
35-40 faculty, staff, graduate students and post-docs
Focus on petascale simulation, with access to state ofthe art
hardware
Experimental program for validation and
uncertaintyquantification
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PRISM Mission
Accelerate substantially the development of MEMStechnologies for
civilian and defense applications
Significantly improve understanding of long-termreliability of
MEMS and survivability in harshenvironments
Achieve this goal by simulating rigorously with
quantifieduncertainty, the physics of failure coupled electrical,
mechanical, thermal and materials behavior
from atoms to devices
verification and validation
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MEMS the Word !
http://www.forbes.com
Digital lightprojection
Airbag sensors
Pressuresensors
DNA chipsInkjet printers
Opticalswitches
Gyroscopes
MEMSmicrophonesin laptops andcell phones
Accelerometersin iPhones andNintendo Wii
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MEMS Performance Requirements
MEMS must satisfy stringent requirementsbefore inclusion in NNSA
stockpile
Survive billions of cycles of operation
Survive dynamic impact conditions High gup to 30,000 g over
milliseconds
Large range in operating temperatures
Typically -50C to 80C
Must function after long storage
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Failure Mechanisms
PRISM Focus
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Target PRISM Device
Contacting capacitive RF MEMS switch
Used for contact actuators and capacitiveswitches
Metal membrane makes periodic contact withthin dielectric
layer
Al Membrane
Dielectric
Pull-downelectrode
Anchor
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Failure Mechanisms
Dielectric Charging
Contact Area Damage
Current Channeling
Mechanical Failure
Mechanismspoorly understoodbut of fundamentalscientific
interest!
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UncertaintySimulation inputs
are inherentlyuncertain!
Electrodeposited LIGA Nimicrotensile specimens(Hemker and
Sharpe, Ann.Rev. Mater. Res, 2007)
Uncertainty ininputs Uncertainty in
outputs
SimulationInput
PDF
Output
PDF
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Multiphysics/Multiscale Simulation
Vbias
= 60-80V
Vbias
= 0
Device scale:
~1-100s m,~1 s
ElectrostaticsChargetransportStructural
deformationThermalsContinuumand rarefiedgas dynamics
Microscale:
~10-100 nm,
~1-100 ns
Contact area
evolutionDefect
anddislocationevolutionSurfacechemistryCapillarycondensation
Billions of cyclesof operation
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Microstructure
characterization(initial,intermediate,final)
Scanner
Lens
Sample
Low Vibration Lab
Vibrationisolation slab
Detailedstructuralvibrationmeasurements
DIELECTRIC
TOP METAL ELECTRODE
CONTROL
VOLTAGE
BOTTOM METAL ELECTRODE
DIELECTRIC
TOP METAL ELECTRODE
CONTROL
VOLTAGE
Dielectric charging,thermal, electro-thermal,
creepexperiments
Uncertainty quantificationexperiments
Experimental Program
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PRISM Software Architecture
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Computational Power
LLNL Hera, LANL Lobo
Steele848 x 8 core Dell 1950
60 teraFLOPS
Coates1,000 x 8 core HP DL165
All 10 GigE90 teraFLOPS
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Why PRISM ?Interdisciplinary team ofresearchers in AAE, ECE,
ME,MSE, Math, CS, CSE, Software
Students from
top-rankedprograms
BirckNanotechnology
Center
Experimental dataleveraged fromPurdue, Sandia and
IMPACT Center
nanoHUB.orgmemsHUB.org
