MICRO ELECTRO MECHANICAL SYSTEMS FOR CRACK … Meeting... · •• Prototyping Prototyping ofof...
Transcript of MICRO ELECTRO MECHANICAL SYSTEMS FOR CRACK … Meeting... · •• Prototyping Prototyping ofof...
S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
MICROMICRO‐‐ELECTROELECTRO‐‐MECHANICAL SYSTEMS FOR CRACK MECHANICAL SYSTEMS FOR CRACK
MONITORING IN AGEING INFRASTRUCTURESMONITORING IN AGEING INFRASTRUCTURESMONITORING IN AGEING INFRASTRUCTURESMONITORING IN AGEING INFRASTRUCTURES
A. RoncagliaA. Roncaglia11, M. Ferri, M. Ferri11, F. Mancarella, F. Mancarella11, J. Yan, J. Yan22, A. A. Seshia, A. A. Seshia22, K. , K. SogaSoga22, J. Zalesky, J. Zalesky33
1 1 CNR, Institute of Microelectronics and Microsystems (IMM), Bologna, ItalyCNR, Institute of Microelectronics and Microsystems (IMM), Bologna, Italy22 U i it f C b id E i i D t t C b id UKU i it f C b id E i i D t t C b id UK2 2 University of Cambridge, Engineering Department, Cambridge, UKUniversity of Cambridge, Engineering Department, Cambridge, UK
3 3 Technical University in Prague, Faculty of Civil Engineering, Technical University in Prague, Faculty of Civil Engineering, Prague, Czech RepublicPrague, Czech RepublicPrague, Czech RepublicPrague, Czech Republic
S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
OutlineOutline
•• UndergroundUnderground MM33 ProjectProject:: MicroMicro--MonitoringMonitoring andand MeasurementMeasurementUndergroundUnderground MM33 ProjectProject:: MicroMicro MonitoringMonitoring andand MeasurementMeasurementSystemSystem forfor AgeingAgeing UndergroundUnderground InfrastructuresInfrastructures
•• MicroMicro--ElectroElectro--MechanicalMechanical SystemsSystems (MEMS)(MEMS) inin crackcrack monitoringmonitoring
•• MEMSMEMS fabricationfabrication•• MEMSMEMS fabricationfabrication
•• Packaging/AssemblyPackaging/Assemblyg g yg g y
•• PrototypingPrototyping ofof MEMSMEMS crackmetercrackmeter andand earlyearly teststests
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
S3T ProjectS3T Project -- Underground M3Underground M3
ProjectProject:: UndergroundUnderground MM33 “Micro“Micro--measurementmeasurement andand monitoringmonitoring systemsystem
S3T Project S3T Project Underground M3Underground M3
ComputerComputer visionvision WirelessWireless sensorsensor networksnetworksProjectProject:: UndergroundUnderground MM33 MicroMicro--measurementmeasurement andand monitoringmonitoring systemsystemforfor ageingageing UndergroundUnderground Infrastructures”,Infrastructures”, EurocoresEurocores SS33TT FPFP66Start: Oct. 1 2006, End: Apr. 30 2010Start: Oct. 1 2006, End: Apr. 30 2010
CoordinatorCoordinator:: ProfProf.. KenichiKenichi Soga,Soga, UniversityUniversity ofof Cambridge,Cambridge, UKUK
P tP t U i itU i it ff C b idC b id (UK)(UK) CNRCNR I tit tI tit t ffPartnersPartners:: UniversityUniversity ofof CambridgeCambridge (UK),(UK), CNRCNR InstituteInstitute ofofMicroelectronicsMicroelectronics andand MicrosystemsMicrosystems (Italy),(Italy), TechnicalTechnical UniversityUniversity ininPraguePrague (Czech(Czech Republic),Republic), UniversidadUniversidad PolitecnicaPolitecnica dede CatalunyaCatalunya (Spain)(Spain)AdvancedAdvanced simulationsimulation methodsmethods MEMSMEMS sensorssensors
AimAim:: DevelopingDeveloping newnew methodsmethods forfor structuralstructural monitoringmonitoring ofof undergroundundergroundinfrastructuresinfrastructures particularlyparticularly undergroundunderground tunnelstunnelsinfrastructures,infrastructures, particularlyparticularly undergroundunderground tunnelstunnels..
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
Underground M3: distributed sensors in tunnelsUnderground M3: distributed sensors in tunnelsgg
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
Objective: MEMS wireless crackmeterObjective: MEMS wireless crackmeterjj
Wall crack
Possible design of MEMSPossible design of MEMS--based wireless crackmeterbased wireless crackmeter
Wall crackWall anchors PCB (wireless
unit/sensor interface)
Silicon chipSilicon chip
Steel bar
Uniaxial strain sensors
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
Objective: MEMS wireless crackmeterObjective: MEMS wireless crackmeter
Crack movement analysis through uniaxial strain detection on a triangular patternCrack movement analysis through uniaxial strain detection on a triangular pattern
jj
1. Expansion 2. Contraction
3. Sliding (A) 4. Sliding (B)
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
MicroMicro--ElectroElectro--MechanicalMechanical--Systems (MEMS)Systems (MEMS)y ( )y ( )
11stst AntisymmetricAntisymmetric 11stst SymmetricSymmetric
anchorsanchors
suspended beamsuspended beam
11 Antisymmetric Antisymmetric resonance mode resonance mode
11 Symmetric Symmetric resonance mode resonance mode
suspended beamsuspended beam
coupling gapcoupling gap
actuationactuationelectrodeselectrodes
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
MEMSMEMS resonatorsresonators asas strainstrain sensorssensors
db]
50
SS eso ato seso ato s asas st ast a se so sse so sAxialAxial loadload ResonanceResonance frequencyfrequency shiftshift
-60
-50
de S
pect
rum
[d
-60
-50
ude
Spec
trum
[db]
-80
-70
brat
ed A
mpl
itud
No Strain)-80
-70
Cal
ibra
ted
Ampl
itu
No Strain 72 strain
437000 438000
-90
Cal
i
Frequency [Khz]437000 438000
-90
Frequency [Khz]
MEMSMEMS
C1
-C2
SelfSelf--sustainedsustained oscillationoscillation atat resonanceresonance
8StrainStrain--dependentdependent oscillatoroscillator
S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
ElectromechanicalElectromechanical propertiesproperties ofof resonantresonant MEMSMEMSp pp p
C RR LL CCII IIMotionalMotional currentcurrent
Vdc
C RRmm LLmm CCmmII IImm
CCftftIIftft
FeedthroughFeedthrough currentcurrent
ForFor closedclosed looploop operationoperation mustmust bebe IIftft <<<< IImm
ftft
mmeqeq αα2222mmeq eq ffrr VVdc dc εε00 SS22mmeqeq ffrr mmeqeq22mmeqeq ffrr αα22
QQ αα22
qqLLmm==
αα22CCmm==
442 2 ffrr2 2 mmeqeq
eqeqRRmm==
Q Q αα22αα ==
dd22ФФ11
eqeq eqeq
442 2 ffrr2 2 mmeqeq
eqeq rr
442 2 ffrr2 2 mmeqeqαα22Q Q αα22
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
TheThe problemproblem ofof packagingpackagingg gg g
MEMSMEMSBondingBonding wireswires
PackagePackage-50
um [d
b]
-50
[db]
SteelSteel
PackagePackage
80
-70
-60
d A
mpl
itude
Spe
ctr
80
-70
-60
ated
Am
plitu
de S
pect
rum
[
437000 438000
-90
-80
Cal
ibra
ted
Frequency [Khz]437000 438000
-90
-80
Cal
ibra
Frequency [Khz]
ElectricalElectrical connectionsconnections
MEMS resonator in air (800 Torr)MEMS resonator in air (800 Torr) MEMS resonator in vacuum (3 mTorr)MEMS resonator in vacuum (3 mTorr)VacuumVacuum packagingpackaging wouldwould bebe inin principleprinciple thethe bestbest solutionsolution
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
ObjectivesObjectives ofof MEMSMEMS activityactivity withinwithin UndergoundUndergound MM33jj yy gg
D l tD l t ff MEMSMEMS f b i tif b i ti t h lt h l ff l t ll t l tt•• DevelopmentDevelopment ofof aa MEMSMEMS fabricationfabrication technologytechnology forfor laterallateral resonatorsresonatorswithwith couplingcoupling gapsgaps scaledscaled belowbelow 11 µmµm..
•• InvestigationInvestigation ofof bondingbonding techniquestechniques suitedsuited toto fixfix thethe MEMSMEMS chipchip ononsteelsteel withwith efficientefficient strainstrain transfertransfer..
•• DevelopmentDevelopment ofof aa vacuumvacuum packagingpackaging techniquetechnique forfor MEMSMEMS strainstrainsensorssensors bondedbonded onon steelsteel..
•• RealizationRealization andand testtest ofof aa firstfirst prototypeprototype ofof MEMSMEMS--basedbased crackmetercrackmeter..
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
MEMS sensors fabrication: process flowMEMS sensors fabrication: process flowpp
Device layer: Si 15 µmDevice layer: Si 15 µm
1. SOI wafer1. SOI wafer 2. SiO2. SiO22 depositiondeposition 3. SiO3. SiO22 RIE etchingRIE etching
Device layer: Si 15 µmDevice layer: Si 15 µmSiOSiO222 µm2 µm
Handle: Si 500 µm Handle: Si 500 µm
4. Polysilicon deposition4. Polysilicon deposition 5. Oxidation5. Oxidation 6. Oxide RIE etching6. Oxide RIE etching
7. Scribeline etching7. Scribeline etching 8. Device layer etching8. Device layer etching 9. HF vapour release9. HF vapour release
10. Metal deposition10. Metal deposition
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
MEMS fabrication: gap narrowing testsMEMS fabrication: gap narrowing testsg p gg p g
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
MEMSMEMS fabricationfabrication –– combcomb--drivedrive DETFDETF sensorsensorSS ab cat oab cat o co bco b d ed e se sose so
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
MEMSMEMS fabricationfabrication –– parallelparallel plateplate DETFDETF sensorsensorSS ab cat oab cat o pa a epa a e p atep ate se sose so
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
MEMS fabrication: resonators with various geometriesMEMS fabrication: resonators with various geometriesgg
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
MEMS fabrication: openMEMS fabrication: open--loop testingloop testing
OpenOpen--looploop measurementsmeasurements onon parallelparallel--plateplate DETFDETF devicedevice::
MEMS fabrication: openMEMS fabrication: open--loop testingloop testing
Vdc=Vdc=2020V,V, --2525dBm,dBm, SignalSignal peakpeak >> 1515dB,dB, Q>Q>2000020000,, ff00==490490kHzkHz
DevicesDevices withwith highhigh QQ andand lowlow feedthroughfeedthrough withwith groundedgrounded substratesubstrate::
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DevicesDevices withwith highhigh QQ andand lowlow feedthroughfeedthrough withwith groundedgrounded substratesubstrate::OKOK forfor closedclosed--looploop operationoperation
S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
Assembly: silicon/steel adhesive bondingAssembly: silicon/steel adhesive bonding
Strain sensors:Strain sensors:•• CEACEA--1313--250UN250UN--120 Vishay 120 Vishay
Adhesives: Adhesives: •• MM--Bond200, twoBond200, two--component cyanoacrylatecomponent cyanoacrylate
y gy g
•• 1111--FAFA--0303--120 RS Components 120 RS Components p y yp y y
•• MM--Bond600, twoBond600, two--component epoxycomponent epoxy
Experimental setup (2)Experimental setup (2)
PCommercial strain gauge
Strain Gauge
Adhesive (M-Bond200 /M-Bond600)
Steel bar
Silicon die
Adhesive (M-Bond200 /M-Bond600)
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Steel bar
S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
Assembly: silicon/steel solder bondingAssembly: silicon/steel solder bonding
Silicon sampleSilicon sample Steel barSteel bar
y gy g
1. Oxide etch1. Oxide etch 1. Oxide etch1. Oxide etch
2. Cu evaporation2. Cu evaporation 2. Sn2. Sn--Pb Pb depositiondeposition
4. Foil strain gauge sticking on silicon sample4. Foil strain gauge sticking on silicon sample
depositiondeposition
33 Pressure and heating (200Pressure and heating (200 °°C)C)
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3. 3. Pressure and heating (200 Pressure and heating (200 C)C)
S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
Assembly: silicon/steel strain transferAssembly: silicon/steel strain transferyy
300L=40 mm t=4mm
Strain Gauge Position3/4 L
) 300
400
Strain Gauge Position1/4 L
L=41 mm t=2mm
s)
100
200
Stra
in (
s
TheoreticalN11-FA-03-120
200
300
Stra
in (
s
0
100 N11 FA 03 120 CEA-13-250UN-120 CEA-13-250UN-120
on silicon (MBond 600).CEA-13-250UN-120
on silicon (MBond 200).0 10 20 30 40
0
100 TheoreticalCEA-13-250UN-120 CEA-13-250UN-120
on silicon
0 5 10 15 20 250
Inflection (mm)
AdhesiveAdhesive bondingbonding
0 10 20 30 40
Inflection (mm)
SolderSolder bondingbondingAdhesiveAdhesive bondingbonding SolderSolder bondingbonding
StrainStrain transfertransfer aroundaround 7070 %% StrainStrain transfertransfer aboveabove 9090 %%
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
Packaging: vacuum packaging by glass softeningPackaging: vacuum packaging by glass softening
Vacuum packaging techniqueVacuum packaging technique Measured vacuum levelMeasured vacuum level
g g p g g y g gg g p g g y g g
0
PrototypePrototype
10-1
100
Torr)
10-2
10 1
ssur
e (T
10-3
10
Pre
s
0 50 100 150 20010
Time (h)
Best result with glass softening method: 300 mTorrBest result with glass softening method: 300 mTorr
Problems in reliabilitProblems in reliabilit21
Problems in reliabilityProblems in reliability
S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
Packaging: vacuum packaging by solderingPackaging: vacuum packaging by soldering
VacuumVacuum sealingsealing withwith metalmetal soldersolder insteadinstead ofof glassglass softeningsoftening
g g p g g y gg g p g g y g
10-1
10-2(Tor
r)P
ress
ure
450 500 550 600
10-3
Time (h)
ResultsResults:: improvedimproved reliabilityreliability improvedimproved vacuumvacuum levellevel ((4040 mTorr)mTorr)22
ResultsResults:: improvedimproved reliability,reliability, improvedimproved vacuumvacuum levellevel ((4040 mTorr)mTorr)
S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
Prototyping: crackmeter prototype with MEMS in vacuumPrototyping: crackmeter prototype with MEMS in vacuumyp g p ypyp g p yp
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
Prototyping: crackmeter prototype with MEMS in airPrototyping: crackmeter prototype with MEMS in airyp g p ypyp g p yp
MEMSMEMS sensorsensor
PiezoresistivePiezoresistive sensorsensor
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
Testing: crackmeter with MEMS in airTesting: crackmeter with MEMS in air
OpenOpen looploop measurementsmeasurements onon CrackmeterCrackmeter prototypeprototype withwith MUMPSMUMPS roundrounddiskdisk resonatorsresonators inin airair..
gg
TheThe devicedevice showsshows somesome sensitivitysensitivity toto strain,strain, butbut itsits electromechanicalelectromechanicalpropertiesproperties seemseem toto bebe unsuitableunsuitable forfor closedclosed--looploop operationoperation (too(too largelargefeedthroughfeedthrough andand lowlow peak,peak, atat leastleast withwith capacitivecapacitive sensing)sensing)
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
Testing: crackmeter with MEMS in vacuumTesting: crackmeter with MEMS in vacuum
CrackmeterCrackmeter prototypeprototype assembledassembled withwith vacuumvacuum packagingpackaging ofof aa parallelparallel--plateplate DETFDETF devicedevice
gg
plateplate DETFDETF devicedevice
MEMS sensor
Piezoresistive sensorPiezoresistive sensor
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S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
Testing: crackmeter strain sensitivityTesting: crackmeter strain sensitivity
MeasurementsMeasurements onon UCAMUCAM--CNRCNR parallelparallel--plateplate resonatorresonator withinwithin thethecrackmetercrackmeter withwith appliedapplied strainstrain
g yg y
crackmetercrackmeter withwith appliedapplied strainstrain..
438,5
Hz]
db]
438,0
Strain releasequen
cy [k
H
-60
-50
e S
pect
rum
[d
437,0
437,5Strain release
nanc
e fre
q
Strain loading
-80
-70
ated
Am
plitu
de
Nostrain 16ustrain 41ustrain 72ustrain92ustrain
0 20 40 60 80 100 120436,5R
eson
Strain [s]
436000 437000 438000 439000
-90
Cal
ibra
Frequency [khz]
92ustrain 107ustrain 118ustrain
StrainStrain sensitivitysensitivity ofof roughlyroughly 1010 Hz/Hz/µStrain,µStrain, stablestable resultsresults withwith constantconstantappliedapplied strainstrain reversiblereversible operationoperation StrainStrain appliedapplied inin thethe rangerange 00--100100 µStrainµStrain
Strain [s]
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appliedapplied strain,strain, reversiblereversible operationoperation.. StrainStrain appliedapplied inin thethe rangerange 00--100100 µStrainµStrain..
S3T Workshop, Porto, 6th-9th Apr. 2010IMM Bologna
ConclusionsConclusions
•• AA technologytechnology forfor thethe fabricationfabrication ofof laterallateral SOISOI MEMSMEMS resonatorsresonators withwith goodgoodfeedthroughfeedthrough immunityimmunity andand QQ upup toto 5050,,000000 inin vacuumvacuum hashas beenbeen developeddeveloped..
•• StrainStrain transfertransfer fromfrom steelsteel toto siliconsilicon hashas beenbeen evaluatedevaluated toto bebe aroundaround 7070 %% withwithadhesiveadhesive bondingbonding andand aboveabove 9090 %% withwith soldersolder bondingbonding..
•• AA crackmetercrackmeter prototypeprototype hashas beenbeen assembledassembled usingusing aa vacuumvacuum--packagedpackaged parallelparallel--plateplateMEMSMEMS resonatorresonator andand testedtested withwith aa measurementmeasurement setupsetup..
•• OpenOpen--looploop testingtesting ofof thethe crackmetercrackmeter waswas successful,successful, withwith resonatorresonator QQ aroundaround 90009000forfor VacVac == 00..0505 VV andand peakpeak heightheight aroundaround 2020 dBdB.. StrainStrain sensitivitysensitivity aroundaround 1010Hz/µStrainHz/µStrain andand measurementmeasurement repeatabilityrepeatability werewere alsoalso demonstrateddemonstrated usingusing thisthisprototypeprototype..
Future developmentsFuture developments
•• ImplementationImplementation ofof closedclosed--looploop oscillationoscillation forfor thethe crackmetercrackmeter withwith vacuumvacuum packagedpackagedMEMSMEMS..
pp
•• OnOn--fieldfield testingtesting ofof thethe crackmetercrackmeter inin PraguePrague UndergroundUnderground..
•• ImplementationImplementation andand testingtesting ofof multimulti--directionaldirectional strainstrain sensingsensing modulemodule onon aa newnewcrackmetercrackmeter prototypeprototype..
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