B.A.Bryce

Brian A. Bryce, Jason J. Gorman, Sergiy Krylyuk, and Albert Davydov

Silicon nanowire mass sensors

B.A.Bryce

Outline• Introductiontovapor-liquid-solidnanowiregrowth• Literaturenanomechanical measurementofmass• Ouridea• ExperimentalResults• Questions

B.A.Bryce

In1964,R.S.WagnerandW.C.Ellisfirstobserved thegrowthof siliconcrystalsfromAuparticlesduetothepresenceofasiliconvapor.

Thewiresweresolid, theparticlewasaliquideutecticandtheprecursorwasavaporsotheycalledthemethod:vapor-liquid-solid (VLS)growth.

Itdependsontheeutecticpointofabinaryphasediagram.

VLSgrowthwasoriginallycalledwhiskergrowth inthe1970sfollowingWagnerandEllis’sworkbuteventuallyevolvedinthe1990sintonanowiregrowth,capableofcreatingrodsatnanoscaledimensions.

Vapor-liquid-solidnanowiregrowth

B.A.Bryce

Attogram detectionusingnanoelectromechanicaloscillators

B.Ilic,H.G.Craighead,S.Krylov,W.Senaratne,C.Ober,andP.Neuzil,J.Appl.Phys.95,3694(2004).

𝑓" =𝛽𝑙 &

2𝜋𝑡𝑙&

𝐸12𝜌(1 + 4𝛾)

�

𝛾 =𝑚𝜌𝐴𝑙

Resolvablemass=0.39ag

B.A.Bryce

Nanowirecantileversformassbasedsensing

Idea:Usesitecontrolled growthofSivapor-liquid-solidwirestocreatehighsensitivitymasssensingplatform

𝑓" =𝛽𝑙 &

12𝜋𝑡𝑙&

5𝐸2𝜌

�

𝛽𝑙 ⇒ 𝑠𝑜𝑙𝑢𝑡𝑖𝑜𝑛𝑡𝑜𝑡𝑟𝑎𝑛𝑠𝑖𝑑𝑒𝑛𝑡𝑖𝑎𝑙

Taperedregularhexagonwithendmass:

B.A.Bryce

Phase1:Sitecontrolledgrowthandsensitivity

Idea Reality

𝑄 > 13000

Estimatedresolvablemass=0.07-0.14ag

𝜎F = 0.5 − 1𝐻𝑧

B.A.Bryce

Questions?

B.A.Bryce

SiliconnanowiremasssensorsBrianA.Bryce,JasonJ.Gorman,SergiyKrylyuk,andAlbertDavydov

20µm

Idea Reality

Betterthan0.14attogramsensitivity

(0.00000000000000000014 g)

B.A.Bryce

Attogram detectionusingnanoelectromechanicaloscillators

B.Ilic,H.G.Craighead,S.Krylov,W.Senaratne,C.Ober,andP.Neuzil,J.Appl.Phys.95,3694(2004).

2µm

𝑓" =𝛽𝑙 &

2𝜋𝑡𝑙&

𝐸12𝜌(1 + 4𝛾)

�

𝛾 =𝑚𝜌𝐴𝑙

𝑄 = 8500

Resolvablemass=0.39ag

B.A.Bryce

Measurementprinciple- Fabry–Pérot interferometer

𝑑LFF

𝑎 = 𝛼N cos 𝜔𝑡

𝑏 = 𝛼&cos(𝜔𝑡 +4𝜋𝑑LFF𝜆 )

Cantilever

Substrate

B.A.Bryce

Nanowirecantileversformassbasedsensing

Idea:Usesitecontrolled growthofSivapor-liquid-solidwirestocreatehighsensitivitymasssensingplatform

Motivation:

• Likelyhigh-Qaswiresaredamagefreeandsinglecrystal

• Auontipcanbefunctionalized andismostsensitivelocationformassloading

• CanbeintegratedwithotherSibasedtechnologytoallowformultiplexing

• Canbescaledtonanoscopic dimensions withoutelectronbeamlithography

• Highly integratedsensor isaninterestingmetrologysystem-on-a-moduleproblem

𝑓" =𝛽𝑙 &

12𝜋𝑡𝑙&

5𝐸2𝜌

�

Goal:OnechipandPCBwithsamemeasurementqualityasentirelabofequipment

𝛽𝑙 ⇒ 𝑠𝑜𝑙𝑢𝑡𝑖𝑜𝑛𝑡𝑜𝑡𝑟𝑎𝑛𝑠𝑖𝑑𝑒𝑛𝑡𝑖𝑎𝑙

Taperedregularhexagonwithendmass:

B.A.Bryce

Phase1:Showsitecontrolledgrowthonsidewallsofhigh-QVLScantilevers,andestimatemasssensitivity

Phase2:Integratephotodetector, andthermaldrivertoallowforpartialmultiplexing

Phase3:Integratelightsourceforfullmultiplexing

Phase4:Integratevacuumpumptocompletehigh resolutionmassdetectionsystem

B.A.Bryce

Phase1:Showsitecontrolledgrowthonsidewallsofhigh-QVLScantilevers,andestimatemasssensitivity

B.A.Bryce

4µm

1) Growawirewherewewant

2) Growitinaparticulardirection

3) Growone wire

Controlisneeded

B.A.Bryce

Nanowirereactor

SystemFeatures:q 4-zonefurnace;quartzreactorfor2”wafersq Variablepressure(3mTorr – 760Torr)withN2/H2 carriergasq SiH4 andSiCl4 precursorsq Insitu dopingforn- (PH3)and p- (BCl3)types

Exhaust

I II III IVInlet

SiNWsgrowthconditions:

Tgrowth =500-- 1050Cà 900C

P=10-- 760Torrà 600Torr

Growthrate=0.1-- 10um/min

SiH4v Sis400-650C

10-600 torr

SiCl4v Sis900C

B.A.Bryce

Phase1:Sitecontrolledgrowthandsensitivity

Idea Reality

B.A.Bryce

Theinstrument(Phase1)He

NeLaser

Polarizer Polarizer

BS

BS

LED

Köhler

illum

inatior

Objective Dichroicmirror

TubeLens CameraPhotodiode

He/Arinlet

Todrypump

VacuumChamber

OnXYZstage

ToElectronics

B.A.Bryce

Theinstrument(Phase1)

Photodetector TransimpedanceAmplifier

Piezo

NetworkAnalyzer

B.A.Bryce

Phase1:Sitecontrolledgrowthandsensitivity

Idea Reality

𝑄 > 13000

Estimatedresolvablemass=0.07-0.14ag

𝜎F = 0.5 − 1𝐻𝑧

B.A.Bryce

Phase2devicedesign

HeaterPhotodiode

NanowireSensor

Metal1

Metal2

Au

p-Si

n-Si

SiO2

B.A.Bryce

Phase2devicerealityHeaterPhotodiode

NanowireSensor

Metal1

Metal2

Au

p-Si

n-Si

SiO2

10layersoflithography!1. Markdefinition(L+RIE)2. Oxidize(RCA+tube)3. Trenchdefinition(L+RIE+KOH)4. Oxidize(RCA+tube)5. VIAfordiode (L+RIE+HF)6. n+ poly-Sigrowth7. PolySelect1(L+RIE)8. PolySelect2(L+RIE)9. M0Liftoff(L+evaporation)10. PECVDSiO2+SiNx11. VIAthroughSiNx (L+RIE)12. Windowopen(L+HF)13. Audeposition (L+HF+evaporation)14. Wiregrowth15. Contacts(L+HF+evaporation)

20µm

B.A.Bryce

20µm

Useyourtitleslideeffectively:• Coremessage• Getpeopletowanttolisten

B.A.Bryce

Brian A. Bryce, Jason J. Gorman, Sergiy Krylyuk, and Albert Davydov

Silicon nanowire mass sensors

B.A.Bryce

SiliconnanowiremasssensorsBrianA.Bryce,JasonJ.Gorman,SergiyKrylyuk,andAlbertDavydov

20µm

Idea Reality

Betterthan0.14attogramsensitivity

(0.00000000000000000014 g)

B.A.Bryce

20µm

Outlineswastetime*

*Exceptionfortalkslongerthan1hourorsuperformalsettings

B.A.Bryce

Outline• Introductiontovapor-liquid-solidnanowiregrowth• Literaturenanomechanical measurementofmass• Ouridea• ExperimentalResults• Questions

B.A.Bryce

20µm

Keeptexttominimum

Textheavyslidesaregenerallybad

B.A.Bryce

In1964,R.S.WagnerandW.C.Ellisfirstobserved thegrowthof siliconcrystalsfromAuparticlesduetothepresenceofasiliconvapor.

Thewiresweresolid, theparticlewasaliquideutecticandtheprecursorwasavaporsotheycalledthemethod:vapor-liquid-solid (VLS)growth.

Itdependsontheeutecticpointofabinaryphasediagram.

VLSgrowthwasoriginallycalledwhiskergrowth inthe1970sfollowingWagnerandEllis’sworkbuteventuallyevolvedinthe1990sintonanowiregrowth,capableofcreatingrodsatnanoscaledimensions.

Vapor-liquid-solidnanowiregrowth

B.A.Bryce

20µm

LabelthingsclearlyMakefontslargeenoughtoread

B.A.Bryce

Attogram detectionusingnanoelectromechanicaloscillators

B.Ilic,H.G.Craighead,S.Krylov,W.Senaratne,C.Ober,andP.Neuzil,J.Appl.Phys.95,3694(2004).

Resolvablemass=0.39agNoscale

Toosmall

B.A.Bryce

Attogram detectionusingnanoelectromechanicaloscillators

B.Ilic,H.G.Craighead,S.Krylov,W.Senaratne,C.Ober,andP.Neuzil,J.Appl.Phys.95,3694(2004).

2µm

𝑓" =𝛽𝑙 &

2𝜋𝑡𝑙&

𝐸12𝜌(1 + 4𝛾)

�

𝛾 =𝑚𝜌𝐴𝑙

𝑄 = 8500

Resolvablemass=0.39ag

B.A.Bryce

20µm

Clearlyexplainwhyyouhavemadedesignchoices

B.A.Bryce

Nanowirecantileversformassbasedsensing

Idea:Usesitecontrolled growthofSivapor-liquid-solidwirestocreatehighsensitivitymasssensingplatform

𝑓" =𝛽𝑙 &

12𝜋𝑡𝑙&

5𝐸2𝜌

�

𝛽𝑙 ⇒ 𝑠𝑜𝑙𝑢𝑡𝑖𝑜𝑛𝑡𝑜𝑡𝑟𝑎𝑛𝑠𝑖𝑑𝑒𝑛𝑡𝑖𝑎𝑙

Taperedregularhexagonwithendmass:

B.A.Bryce

Nanowirecantileversformassbasedsensing

Idea:Usesitecontrolled growthofSivapor-liquid-solidwirestocreatehighsensitivitymasssensingplatform

Motivation:

• Likelyhigh-Qaswiresaredamagefreeandsinglecrystal

• Auontipcanbefunctionalized andismostsensitivelocationformassloading

• CanbeintegratedwithotherSibasedtechnologytoallowformultiplexing

• Canbescaledtonanoscopic dimensions withoutelectronbeamlithography

• Highly integratedsensor isaninterestingmetrologysystem-on-a-moduleproblem

𝑓" =𝛽𝑙 &

12𝜋𝑡𝑙&

5𝐸2𝜌

�

Goal:OnechipandPCBwithsamemeasurementqualityasentirelabofequipment

𝛽𝑙 ⇒ 𝑠𝑜𝑙𝑢𝑡𝑖𝑜𝑛𝑡𝑜𝑡𝑟𝑎𝑛𝑠𝑖𝑑𝑒𝑛𝑡𝑖𝑎𝑙

Taperedregularhexagonwithendmass:

B.A.Bryce

20µm

Endwiththemessageyouwantremembered orsomethingtomake

peopletalktoyouafter

B.A.Bryce

Questions?

B.A.Bryce

Phase2devicerealityHeaterPhotodiode

NanowireSensor

Metal1

Metal2

Au

p-Si

n-Si

SiO2

10layersoflithography!1. Markdefinition(L+RIE)2. Oxidize(RCA+tube)3. Trenchdefinition(L+RIE+KOH)4. Oxidize(RCA+tube)5. VIAfordiode (L+RIE+HF)6. n+ poly-Sigrowth7. PolySelect1(L+RIE)8. PolySelect2(L+RIE)9. M0Liftoff(L+evaporation)10. PECVDSiO2+SiNx11. VIAthroughSiNx (L+RIE)12. Windowopen(L+HF)13. Audeposition (L+HF+evaporation)14. Wiregrowth15. Contacts(L+HF+evaporation)

20µm

B.A.Bryce

20µm

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