1

Seizo MoritaSeizo Morita, Yoshiaki Sugimoto, , Yoshiaki Sugimoto, NoriakiNoriaki OyabuOyabu, , Ryuji Nishi,Insook Yi, Yoshihide Seino, Oscar Oscar CustanceCustance and and M.AbeM.Abe

Graduate School of Engineering, Osaka University

In this review talk, we will introduce:

(3) Chemical IdentificationChemical Identification of Atom Speciesof Atom Species.

(4)&(5) Mechanical Atom Manipulation at LT and RTMechanical Atom Manipulation at LT and RT

(2) PrinciplesPrinciples and PerformancePerformance of NCNC--AFMAFM.

Atom Selective Imaging Atom Selective Imaging andand Atomic Force vs. Z distanceAtomic Force vs. Z distance

Site-Specific Force Spectroscopy, Atom Manipulation and Artificial Nanostructuring

SiteSite--Specific Force SpectroscopySpecific Force Spectroscopy, , Atom Atom ManipulationManipulation and and Artificial Artificial NanostructuringNanostructuring

CEAC Summer Workshop on: Nanoanalysis, Monday & Tuesday, July 10 & 11, 2006 in the ETH main building, Lecture hall: HG E 1.1, ETH Zentrum, 8092 Zürich, Switzerland,

Keynote lecture Morita Tuesday, 11.7. 09:00-10:00 Chair: V. Sandoghdar (ca. 45 (max. 50) minutes)

(5) Vertical(5) Vertical and and (6)(6) Lateral Lateral Atom ManipulationAtom Manipulation

(6) Atom Inlay at RTAtom Inlay at RT.Assembly Assembly of of NanostructureNanostructure from from Two Atom SpeciesTwo Atom Species

Modification Modification of of Atomic StructureAtomic Structure made of made of One Atom SpeciesOne Atom Species

(1) HistoryHistory of of NNononCContactontact (NC)(NC) AFMAFM

Universidad Autonoma de MadridPablo Pablo PouPou, , PavelPavel JelinekJelinek, Rub, Rubéén n PPéérezrez

2

ImagingImaging

Repulsive ForceRepulsive Force

NNearearCContactontact AFMAFMAtom ManipulationAtom Manipulation

History of History of AFMAFM

Since 1986(1) ContactContact AFMAFM

[destructive][StrongStrong repulsive force]

Atom AssemblyAtom Assembly

Precisely Precisely controlledcontrolledNNearearCContactontact

Displacement Sensor

contactcontact

Displacement Sensor

0(2) TappingTappingAFM/AFM/CyclicCyclicContactContact

cyclic contactcyclic contact

Displacement Sensor

DynamicDynamic

DynamicDynamic

[WeakWeak repulsive force]

(1) (1) HistoryHistory of of NonContactNonContact (NC)(NC) AFMAFM

ImagingImaging

Since 1995

True Atomic ResolutionTrue Atomic Resolution[WeakWeak attractive force]

[nondestructive]

(3) (3) NNononCContactontact AFMAFMAttractive Attractive ForceForce

Displacement Sensor

noncontactnoncontact

DynamicDynamic

3

19871987 Lattice Image of GraphiteLattice Image of Graphite obtained using SiO2 micromicro--cantilevercantilever under contact regioncontact regionG.Binnig, Ch.Gerber, E.Stoll, T.R.Albrecht and C.F.Quate

Europhys.Lett, 3 (12) (1987) pp.1281-1286.

19901990 OpticalOptical--beambeam--deflectiondeflection AFM and lattice image of NaCl(001)lattice image of NaCl(001) under UHVG.Meyer and N.M.Amer, Appl.Phys.Lett. 56 (1990) pp.2100-2101.

Beginning Beginning ofof AFMAFM: Simple : Simple contact AFMcontact AFM measurementmeasurement

19911991 Frequency modulation (FM) methodFrequency modulation (FM) method combined with large amplitudelarge amplitude and high Qhigh QT.R.Albrecht, P.Grutter, D.Horne and D.Ruger, J.Appl.Phys. 69 (1991) 668.

1988 1988 Optical fiberOptical fiber--based interferometerbased interferometer AFM D.Ruger, H.J.Mamin, R.Erlandsson, J.E.Stern and B.D.Terris,

Rev.Sci.Instrum. 53 (1988) 2337.

19861986 InventionInvention of Atomic Force Microscope (AFMAFM)G.Binnig, C.F.Quate and Ch.Gerber, Phys.Rev.Lett. Vol.56 (1986) pp.930-933.

Dawn Dawn ofof NoncontactNoncontact AFM AFM with true atomic resolutionwith true atomic resolution

19921992 K and Br ionsK and Br ions, and monostepmonostep with atomic resolutionwith atomic resolution of KBr(001) in UHV at 4.2KF.J.Giessibl and G.Binnig, Ultramicroscopy, 42-44 (1992) pp.281-289, pp.7-15.

History of Noncontact AFMHistoryHistory ofof NoncontactNoncontact AFMAFM

4

InP(110)InP(110)

Si(111)Si(111)--(7x7)(7x7)

19951995 Si(111)Si(111)--(7x7)(7x7) by noncontact AFM, F.J.GiessiblF.J.GiessiblScience 267 (1995) pp.68-71 [30 Aug.199430 Aug.1994; accepted 31 Oct.1994]

19951995 Si(111)Si(111)--(7x7)(7x7) by noncontact AFM, S.KitamuraS.Kitamura and and M.IwatsukiM.Iwatsuki, Jpn.J.Appl.Phys. 34 (1995) pp.L145-L148[Nov.14, 1994Nov.14, 1994; Accepted Dec.6, 1994]

19951995 Atomic point defectsAtomic point defects of InP(110)InP(110) cleaved surfacecleaved surface by noncontact AFM, H.UeyamamH.Ueyamam, , M.OhtaM.Ohta, , Y.SugawaraY.Sugawara and and S.MoritaS.Morita,JpanJ.Appl.Phys. 34 (1995) pp.L1086-L1088 [May 31, 1995May 31, 1995; accepted July 13, 1995]

1995 1995 Defect MotionDefect Motion of Atomic point defectsAtomic point defects of InP(110),InP(110),Y.SugawaraY.Sugawara, , M.OhtaM.Ohta, , H.UeyamamH.Ueyamam and and S.MoritaS.Morita,Science 270 (1995) pp.1647-1648 [27 July, 199527 July, 1995; accepted 11 Oct, 1995]

19971997 Dissipation imageDissipation image of NaCl(001)NaCl(001) and by noncontact AFM, M.Bammerlin, R.Luthi, E.Meyer, A.Baratoff, J.Lu, M.Guggisberg, Ch.Gerber, L.Howaldand H.-J.Guntherodt, Probe Microscopy, 1 (1997) pp.3-9.

19971997 TiOTiO22(110)(110) by noncontact AFM, K.Fukui, H.Onishi and Y.Iwasawa, Phys.Rev.Lett, 79 (1997) pp.4202-4205.

NaCl(001)NaCl(001)TiO2(110)TiO2(110)

In 1995, Achievement of In 1995, Achievement of True Atomic ResolutionTrue Atomic Resolution

Si(111)Si(111)--(7x7)(7x7)

Beginning of Beginning of NoncontactNoncontact AFM AFM with true atomic resolutionwith true atomic resolution

5

1998 1998 First International Workshop on First International Workshop on NoncontactNoncontact Atomic Force MicroscopyAtomic Force MicroscopyConvention Center, Osaka University, July 21-July 23, 1998

Proceedings [Appl.Surf.SciAppl.Surf.Sci. 140 (3. 140 (3--4) (1999) pp.2434) (1999) pp.243--456456]

Ag(111)Ag(111) Cu(111)Cu(111)

C60/Si(111)C60/Si(111) Graphite(0001)Graphite(0001)at 22 Kat 22 K

Far NearTip-to-Sample distance

InAs(110)InAs(110)

Si(111)Si(111)√√33×√×√33--AgAg

TGSTGS

MetalMetal

MoleculeMolecule

Ferroelectric Ferroelectric materialmaterial

Force SpectroscopyForce Spectroscopy

GaAs(110)GaAs(110)GaAs(110)GaAs(110)TopographyTopography Charge ImagingCharge Imaging by by EFMEFM

(a) (b)

TopographyTopography CPD ImagingCPD Imaging by by KPFMKPFMSi(111)7x7 with Ag Si(111)7x7 with Ag depositesdeposites

Layer materialLayer materialVan Van derder WaalsWaals ForceForce

tiptip--toto--sample distance dependence of sample distance dependence of ncnc--AFM imageAFM image

8 years ago8 years ago

6

Si(001)2x1(-32Hz)

Si(001)c(4x2)(-24Hz)

Ge(105)-(1×2) Ge(105)-(1×2)

STM nc-AFM

2004 2004 Seventh International Conference on Seventh International Conference on NoncontactNoncontact Atomic Force Microscopy,Atomic Force Microscopy,the University of Washington (UW), 12-15 September 2004, Seattle, USAProceedings [Nanotechnology, Vol.16, No.3 (2005) pp.S1Nanotechnology, Vol.16, No.3 (2005) pp.S1--S137S137]This conference inThis conference in SeattleSeattle was the first meeting held inwas the first meeting held in USAUSA.. ncnc--AFM 2004AFM 2004Atomic ResolutionAtomic Resolution

Atomic Resolution Beyond STMAtomic Resolution Beyond STM

C12 monolayer underan ambient condition (Q = 292)

Sn/Si(111)-(√3×√3)R30º

Sn/Si(111)-(7x7)

Imaging MoleculesImaging MoleculesAtom Discrimination (Chemical Identification)Atom Discrimination (Chemical Identification)

before after

c da bGe(111)-c(2x8)[01-1] 78.6 K

Vertical Vertical Atom ManipulationAtom Manipulation

Control of Atomic Force and Atom RelaxationControl of Atomic Force and Atom Relaxation

Lateral Lateral Atom ManipulationAtom Manipulation

““Atom InlayAtom Inlay””Embedded Atom LettersEmbedded Atom Letters

Molecular and Molecular and SubmolecularSubmolecularResolution Even in LiquidResolution Even in Liquid

Sn/Si(111)-(2√3×2√3)

7

First English Book on NC-AFMFirst English Book on NCFirst English Book on NC--AFMAFM

Citations 112Citations 112 S.Morita, R.Wiesendanger and E.Meyer (eds.); “Noncontact Atomic Force Microscopy”, Springer, NanoScience and Technology, the end of August (20022002) pp.1-439

8Oscillation Frequency of CantileverνO

scill

atio

n A

mpl

itude

A0∆ν

Frequency ShiftFrequency Shift

Weak Attractive ForceWeak Attractive Force

DisplacementDetection of Frequency ShiftDetection of Frequency Shift

MechanicalMechanicalResonantResonantOscillationOscillation

How to detect Weak Attractive ForceWeak Attractive Force?How to Achieve True Atomic Resolution?How to Achieve True Atomic ResolutionTrue Atomic Resolution?

NoncontactNoncontact AFMAFM

atomic point defectatomic point defect

(2)(2) PrinciplesPrinciples and and PerformancePerformance of of NCNC-- AFMAFM

ν0∼150kHz

k

mKts

9

CantileverX,Y

Z+δZ

Sample

∆ν

Topography

Frequency Shift

Image12

∆Ζ

∆ν

δZ

FM Demodulator

Fiber-Optic Interferometer

Feedback and Scan Circuits

Feedback LoopFeedback Loop

AGC Circuit

Phase Shifter

NC-AFM using the FM detection methodFM detection method. This system has three feedback loopsthree feedback loops.

Schematic diagram of the NC-AFMSchematic diagramSchematic diagram of the NCof the NC--AFMAFMHow to detectHow to detect Weak Attractive ForceWeak Attractive Force??

Oscillation Frequency of Cantilever

νOsc

illat

ion

Am

plitu

de

A0∆ν

Frequency ShiftFrequency Shift

ν0

10

How to measure energy dissipation?How to measureHow to measure energy dissipation?energy dissipation?

Sample

Feedback LoopFeedback Loop

Constant Constant Amplitude Amplitude

ModeMode

Constant Constant Excitation Excitation

ModeMode

Exc

itatio

n V

olta

ge [m

V]

Exc

itatio

n V

olta

ge [m

V]

Osc

illat

ion

Am

plitu

de [

Osc

illat

ion

Am

plitu

de [ ÅÅ

]]

CantileverX,Y

Z+δZ

∆ν

Topography

Frequency Shift Image

12

∆Ζ

∆ν

δZ

FM Demodulator

Fiber-Optic Interferometer

Feedback and Scan Circuits

AGC Circuit

Phase Shifter

p-GaAs(110) NA=1.4x10 cm19 －3

p-GaAs(110) NA=1.4x10 cm19 －3

@RT@RT@RT@RT

11

Where is Contact Point?Where is Contact PointContact Point?

p-GaAs(110) NA=1.4x10 cm19 －3

Constant Excitation Mode

NoncontactContactContact Point Decay Length

-0.5 0 0.5 1.0 1.5 2.0-100

-101

-102

7.5

8.0

8.5

9.0

9.5

Tip-Sample Surface Distance Z[nm]

Freq

uenc

y Sh

ift ∆ν(

Hz)

Osc

illat

ion

Am

plitu

deA

0[ n

m]

(c)z~ 0.08nm(b)z~ 0.1nm (a)z~ 0.4nm

1 2

L1~ 0.16nmL2~ 1.1nm

Where is Noncontact Region?Where is NoncontactNoncontact RegionRegion?

@RT@RT

12

11.5nm12

.2H

z

∆ν = -70Hz

4.57

Hz

11.5nm

∆ν = -62Hz

1.91

Hz

11.5nm

∆ν = -31Hz(a)z~0.4nm (b)z~0.1nm (c)z~0.08nm

Journal of Crystal Growth, Vol.210, 408 (2000)

Where can we obtain True Atomic Resolution?Where can we obtain True Atomic ResolutionTrue Atomic Resolution?

8 Hz8 Hz0.02 nm0.02 nm

8Hz 20pm 0.1Hz0.1Hz 0.25pm0.25pm1mHz1mHz 2.5fm2.5fm

p-GaAs(110) NA=1.4x10 cm19 －3

@RT@RT

13

Preparation ChamberAFM

ChamberLoad Lock Chamber

☆ UHV: ~4×10-11Torr

Home-built RT-UHV-NC-AFMHomeHome--builtbuilt RTRT--UHVUHV--NCNC--AFMAFMSchematic Side View Cantilever (Sb-doped n+Si)

Ar+ Ion Sputtering k=41-49N/mν0=169-172kHzQ=38,000 in UHVTip Radius:5-10nmA0=3nm-10nm

““Atom InlayAtom Inlay””Embedded Atom LettersEmbedded Atom Letters

14

DNADNA ImageImage

7nmx7nm7nmx7nmBB--DNADNA

High Resolution NCHigh Resolution NC--AFM ImagesAFM ImagesNonContact AFM (NC-AFM)NonContactNonContact AFM (NCAFM (NC--AFM)AFM)

Langmuir, 16 (3), 1349 -1353, 2000. T.Uchihashi, M.Tanigawa, M.Ashino, Y. Sugawara, K.Yokoyama, S.Morita, and M.Ishikawa

Appl.Surf.Sci. Vol.157, No.4 (2000) pp.244-250.T.Uchihashi, T.Ishida, M.Komiyama, M.Ashino, Y.Sugawara, M.Mizutani, K.Yokoyama, S.Morita, H.Tokumoto and M.Ishikawa,

Organic monolayersOrganicOrganic monolayersmonolayers

Adenine MoleculesAdenineAdenine MoleculesMolecules

@RT@RT@RT@RT

15

LiF(100) LiF(100)

2nm×2nm

Ag(111)Ag(111)

InsulatorInsulator

3838ÅÅx38x38ÅÅ

SnSn//SiSi(111)(111)√3×√3

mosaicmosaic phase SnSn=1/6 =1/6 MLML Sn:50%Sn:50% Si:50%Si:50%

MetalMetalon Si(111)on Si(111)

Atomically Resolved NCAtomically Resolved NC--AFM AFM ImagesImages

NonContact AFM (NC-AFM)NonContactNonContact AFM (NCAFM (NC--AFM)AFM)MotionMotion of of Ag Ag

atoms at atoms at step sitestep site@RT@RT

SiSiSnSn

16

SiSiInIn

SiSi InIn

SiSiSiSiInIn

Cantilever

InIn

Deflection

Displacement sensor

SelectiveSelectivemanipulation/

assembly

Evaporation of many atom species many atom species

TipTip

Chemical Chemical Identification:Identification:

Many atom speciesMany atom species

Strong bondStrong bond

AFMAFM InsulatorInsulator is is observableobservable

Covalent bondCovalent bond

InsulatorInsulator Ionic bondIonic bondSelective Selective atom atom

manipulation/assembly :

Chemical Chemical IdentificationIdentification

Atomic force measurement Atomic force measurement of individual atomsof individual atoms

Atomic force Atomic force is is measurablemeasurable

RTRT&3D3D--structurestructure

Electronic deviceElectronic device

Novel Novel nanomaterialnanomaterial/Novel /Novel nanodevicenanodevicewithwith Novel functionNovel function

--Mechanical AssemblyMechanical Assembly Using Many Atom SpeciesMany Atom Species--

Displacement sensor

Cantilever Deflection

Novel Bottom Up Nanostructuring SystemNovelNovel Bottom UpBottom Up NanostructuringNanostructuring SystemSystem

17

=> from => from topography with chemical contrasttopography with chemical contrast(=Atom Selective Imaging)(=Atom Selective Imaging)

=> from => from frequency shift vs. tipfrequency shift vs. tip--samplesampledistance curvedistance curve

(=>Force Curve and Potential Curve) (=>Force Curve and Potential Curve)

(3) Chemical IdentificationChemical Identification of Atom Speciesof Atom SpeciesHow to Achieve Chemical Identification?How to Achieve Chemical IdentificationChemical Identification?

Y.Sugimoto, M.Abe, K.Yoshimoto, O.Custance, I.Yi and S.Morita; “Non-contact atomic force microscopy study of the Sn/Si(111) mosaic phase”, Applied Surface Science, Volume 241, Issues 1-2, 28 February (2005) pp.23-27.

M. Abe, Y. Sugimoto, O. Custance, and S. Morita, “Room-temperature reproducible spatial force spectroscopy using atom-tracking technique”, Applied Physics Letters, Vol.87, Issue 17, 24 October (2005) pp.173503-1~173503-3.

Noriaki Oyabu, Pablo Pou, Yoshiaki Sugimoto, Pavel Jelinek, Masayuki Abe, Seizo Morita, Rubén Pérez, and Óscar Custance; “Single Atomic Contact Adhesion and Dissipation in Dynamic Force Microscopy”, Phys.Rev.Lett. Vol.96, No.10 (2006) 106101-1~106101-4.

Y.Sugimoto, P.Pou , O.Custance, P.Jelinek, S.Morita, R.Pérez and M.Abe, “Real topography, atomic relaxations, and short-range chemical interactions in atomic force microscopy: The case of the α-Sn(111)-(√3×√3)R30”, Phys.Rev.B, Vol.73 (2006) pp.205329-1~205329-9.

18

Sn:50%Sn:50% Si:50%Si:50%

mosaicmosaic phase intermediate phase purepure phase

Sn:75%Sn:75% Si:25%Si:25% Sn:99%Sn:99% Si:1%Si:1%

8nm

20nm

Sn:1/6MLSn:1/6ML 1/4ML1/4ML 1/3ML1/3ML

NC-AFM images of SnSn/SiSi(111)-(√3×√3) surfaces

SiSiSnSn

SiSiSnSn

SiSiSnSn

SnSn1/6ML1/6ML

SnSn1/3ML1/3ML

@RT@RT7x77x7

19

SiSiSnSnSiSiSnSn

pure phasepure phase (SnSn:99% :99% SiSi:1%:1%) mosaic phasemosaic phase (SnSn:50% :50% SiSi:50%:50%)

Chemical Identification and Histgram of Sn/Si(111)√3×√3 intermixed surface

Chemical Identification Chemical Identification and and HistgramHistgram of of SnSn//SiSi(111)(111)√3×√3 intermixedintermixed surfacesurface

Sn

Si

(a)

SnSn: 1/3ML: 1/3ML

-0.06 -0.04 -0.02 0.00 0.0202468

10121416182022

Cou

nts

Relative height [nm]

Standard Standard deviationdeviationσσ=2pm=2pm

RTRT

Clear Clear discriminationdiscrimination

pure phasepure phase SnSi(b)

SnSn: 1/6ML: 1/6ML

-0.10 -0.08 -0.06 -0.04 -0.02 0.00 0.020

2

4

6

8

10

12

14

16

Cou

nts

Relative height [nm]

RTRTWide Wide

VariationVariation

？？

mosaic phasemosaic phase

SnSn: 1/3ML: 1/3ML SnSn: 1/6ML: 1/6ML

20

(a)

Sn atom effect surrounding Si atom on Si atom heightSnSn atom effectatom effect surroundingsurrounding SiSi atom onatom on Si Si atom heightatom height

1/6ML1/6MLmosaic mosaic phasephase

SiSi--bbSiSi--aa SnSn

SiSi--aa

SiSi--bbSnSn

30pm

0 2 4 6 8 10 12 14 16 18-1.3-1.2-1.1-1.0-0.9-0.8-0.7-0.6-0.5-0.4-0.3-0.2-0.10.00.1

Z[Å

]

X [Å]

10pm/surround10pm/surround--ing ing SnSn atomatom

RTRT

Charge transferCharge transfer=>=>Change Change of of bonding forcebonding force(Bond order)(Bond order)Z heightZ height(Wave function)(Wave function)

55 SnSn atoms surround SiSi--aa

Charge transfer

2 2 SnSn atoms surround SiSi--bb

SnSn effect surrounding effect surrounding SiSi//SnSn atom atom onon heightheight

Si

No charge trnsfer

SP3

SP3

SiSi

Si Si

Si Si

SiSi

SiSn

Pz

SP2

SnSn

Sn Sn

Sn Sn

SiSi

Si

Sn

Sn: 1/6ML

0 1 2 3 4 5 6-0.10-0.09-0.08-0.07-0.06-0.05-0.04-0.03-0.02-0.010.000.01

Rel

ativ

e he

ight

Rel

ativ

e he

ight

(nm

)

Number of Sn atoms surrounding Si atom

SiSi--aa

SiSi--bb0.665nm

P3

21

NC-AFM images of Sn/Si(111)-(√3x√3)NC-AFM images of SnSn/SiSi(111)-(√3x√3)

(b)(a)

SnSnSiSi

@RT@RT

Far distance

Near distance

(c)

SnSnSiSi

TipTip--Sample distance dependenceSample distance dependence of of atom selective imagingatom selective imaging

SnSnSiSi

22

SnSn//SiSi(111)(111)--((√√3x3x√√3)3)SSFSSSFS & averaging 100100 curvesusing Atom Atom Tracking MethodTracking Method

@RT@RT

0 2 4 6 8 10 12 14 16 18 20

-24-22-20-18-16-14-12-10-8-6-4-20

-18-16-14-12-10-8-6-4-2

Freq

uenc

y Sh

ift ∆

f[H

z]

Tip-Sample Distance Z[Å]

γ[f

N√

m]

SiSi

SnSn

0

height differenceheight difference

ImagingImaging

Long range force

SSFS: Site Specific Force SpectroscopySSFSSSFS: : SSite ite SSpecific pecific FForce orce SSpectroscopypectroscopy

Sn Si

0 2 4 6 8 10 12 14 16 18 20 22 24-3

-2

-1

0

1

2

Shor

t Ran

ge F

orce

F[n

N]

Short Range ForceShort Range ForceSnSn

SiSi

Covalent Covalent Bonding ForceBonding Force

Tip-Sample Distance Z[Å]

0 2 4 6 8 10 12 14 16 18 20 22 24-3

-2

-1

0

1

Shor

t Ran

ge P

oten

tial U

[eV

] Short Range PotentialShort Range Potential

SnSn

SiSi

Tip-Sample Distance Z[Å]

Covalent Bonding Covalent Bonding PotentialPotential

Atom height and Atom height and atom radius etc.atom radius etc.

Disappearance of chemical contrast

23YearYear

“Now”20052000 2010 2015

“5 years later” “10 years later” “Further”“5 years ago”

Chemical Identification of Atom Species by AFMChemical Identification of Atom Species by AFM

1999InAs(110)NCNC--AFMAFM78K&14K

2001年CaF2(111)NCNC--AFMAFM

2003Si and Sbin Si(111) 5√3×5√3-Sb: KPFMKPFM

20073 atom speciesForce curveForce curve

20105 atom species

Intermixed aperiodic atom

distribution

Periodic atom distribution

Atomicallyflat surface

Rough (or amorphous) surface

2015 3 atom species in atom clusteratom cluster

2012 IsolatedIsolated 3 adsorbed atom adsorbed atom speciesspecies

2020 AmorphousAmorphous

20062 atom species : NCNC--AFM in gasAFM in gas

20072 atom species : NCNC--AFM in liquidAFM in liquid

2006 3 atom speciesNCNC--AFMAFM2005Sn/Ge(111)-c(2×8)NCNC--AFMAFM

2004Sn/Si(111)√3×√3NCNC--AFMAFM

20102 atom speciesDissipationDissipation

2005Subsurface(B/Si(111)）

20153-D recognition NMRNMR

Achieved

Achievable

Indeterminate

2006Insulating Surface

24Seizo Morita, Osaka University, Japan (Ed.), Roadmap 2005 of Scanning Probe Microscopy, ca.the end of Aug. 20062006 ca.255 p. 135 illus. Hardcover, NanoScience and Technology, ISBN 3-540-34314-8

First English Book on SPM RoadmapFirst English Book on SPM RoadmapFirst English Book on SPM Roadmap

25

ImagingImaging

ImagingImaging

Repulsive Repulsive ForceForce

Since 1995

True Atomic ResolutionTrue Atomic Resolution

NNearearCContactontact AFMAFMAtom ManipulationAtom Manipulation

History of History of AFMAFM

Since 1986Contact AFM

[destructive][StrongStrong repulsive force]

[WeakWeak attractive force]

[nondestructive]

Atom AssemblyAtom Assembly

Displacement Sensor

noncontactnoncontact

Precisely Precisely controlledcontrolledNearContactNearContact

NNononCContactontact AFMAFMAttractive Attractive ForceForce

Displacement Sensor

contactcontact

Displacement Sensor

0

cyclic contactcyclic contact

Tapping AFM/Cyclic Contact

Displacement Sensor

DynamicDynamic

DynamicDynamic

DynamicDynamic

[WeakWeak repulsive force]

26

(4)(4) Mechanical Atom Manipulation Mechanical Atom Manipulation atat LT LT andandand atatat RTRTRT

VerticalVertical and and LateralLateral Atom ManipulationAtom Manipulation

Modification Modification of of Atomic StructureAtomic Structuremade of made of One Atom SpeciesOne Atom Species

Noriaki Oyabu, Oscar Custance, Masayuki Abe, and Seizo Morita; “Mechanical Atom Manipulation and Artificial Nanostructuring at Low Temperature”, e-Journal of Surface Science and Nanotechnology (e-JSSNT), Vol.4 (2006) pp. 1-8.

by Vertical Contact Methodby by Vertical Contact MethodVertical Contact Method

R. Nishi, D. Miyagawa, H. Etou, Y. Seino, Insook Yi and S. Morita ; “NC-AFM study on atomic manipulation on ionic crystal surface by nanoindentation”, Nanotechnology Vol.17 (2006) S142-S147.

N.Oyabu, O.Custance, I.Yi, Y.Sugawara, and S.Morita; “Mechanical Vertical Manipulation of Selected Single Atoms by Soft Nanoindentation Using Near Contact Atomic Force Microscopy”, Phys.Rev.Lett., Vol.90, No.17 (2003), pp.176102-1~176102-4.

27

How to manipulate selected individual atomsby using “Mechanical Vertical Contact”

How to manipulateHow to manipulate selected individual atomsselected individual atomsby using by using ““Mechanical Vertical ContactMechanical Vertical Contact””

Step 2Mechanical ContactMechanical Contact

Step 1Noncontact imaging Noncontact imaging

Z piezo-scaneerFeedback Controller

Step 3NoncontactNoncontact imagingimaging

Feedback Controller

Approachsignal

*Imaging distance is close to contact point

piez

o-sc

anne

r ext

ensi

on

0time0

Imaging distance

(B) Slow vertical contact*Slow vertical contact*experimentexperiment

piez

o-sc

anne

r ext

ensi

on

Probe and sample were groundedProbe and sample were grounded

Ge(111)-c(2x8)

Clean Si tip

Ge(111)-c(2x8)Ge(111)-c(2x8)

28S.I.PT.S.P

S.I.PT.S.P

UHV: less than 1×10-10Torr

Home-built LT-UHV-NC-AFMHomeHome--builtbuilt LTLT--UHVUHV--NCNC--AFMAFM

AFMChamber

AFMChamber

Preparation Chamber

Preparation Chamber

Load Lock Chamber

Load Lock Chamber

Schematic Side View

Liq.N2

Liq.He

29

Si Removal and Repair of Missing Si Adatom Defect by Mechanical contactSi RemovalSi Removal and RepairRepair of Missing Si Missing Si AdatomAdatom DefectDefect by Mechanical contact

Mechanical frequency : 168.108kHz, Oscillation amplitude : 12.2nm, mfN16−=∆− γ

7×7

Si

11stst ContactContact 22ndnd ContactContact(a)(1) Before Selected Si

adatom Extraction

(b)(1) After Selected Si adatom ExtractionExtraction

[2] Before Repair of Selected

Si adatom Defect

Si

(c)

[2] After RepairRepair of Selected

Si adatom Defect

78K78KSi(111)7××7 DepositionDeposition

30(d) (e) (f)

(a) (c)(b)

Equilateral Equilateral TriangleTriangle

Vertical and Lateral Atom ManipulationVertical Vertical andand LateralLateral Atom ManipulationAtom Manipulation108x108Å

@79K∆f=-20HzGe(111)-c(2x8) Vertical Contact MethodVertical Contact Method

[110] VerticalVerticalExtraction with LateralExtraction with Lateral

11stst ContactContact 22ndnd ContactContactCrystalCrystalAxisAxis

LateralLateralLateral ShiftLateral Shift

VerticalVerticalRepair of Created Repair of Created

Atom VacancyAtom Vacancy

Right Right TriangleTriangle

33rdrd ContactContact

31

(5) Mechanical Atom Manipulation Mechanical Atom Manipulation atat LT LT and atand at RTRT

LateralLateral Atom ManipulationAtom Manipulation

Modification Modification of of Atomic StructureAtomic Structuremade of made of One Atom SpeciesOne Atom Species

N.Oyabu, Y.Sugimoto, M.Abe, O.Custance and S.Morita; “Lateral manipulation of single atoms at semiconductor surfaces using atomic force microscopy”, Nanotechnology 16 (2005) pp.S112–S117.

using the mechanical raster scanusing the using the mechanical mechanical rasterraster scanscan

R. Nishi, D. Miyagawa, H. Etou, Y. Seino, Insook Yi and S. Morita ; “NC-AFM study on atomic manipulation on ionic crystal surface by nanoindentation”, Nanotechnology Vol.17 (2006) S142-S147.

using the mechanical vector scanusing the using the mechanical mechanical vectorvector scanscan

Noriaki Oyabu, Oscar Custance, Masayuki Abe, and Seizo Morita; “Mechanical Atom Manipulation and Artificial Nanostructuring at Low Temperature”, e-Journal of Surface Science and Nanotechnology (e-JSSNT), Vol.4 (2006) pp. 1-8.

32

Lateral manipulation of single atoms with NC-AFMLateralLateral manipulation of manipulation of single atomssingle atoms with with NCNC--AFMAFM

We are deeply involved in developing lateral manipulation with NC-AFM technique

We have many results on lateral manipulation experiments

First experimental evidence of the capability of NCFirst experimental evidence of the capability of NC--AFM technique AFM technique for performing lateral manipulation of atomsfor performing lateral manipulation of atoms

a

NC-AFM topographic images (2.2x3.5 )nm2

f0 = 167485.8 Hz A = 9.3 nmKL = 33.6 N/m T = 79 K Q = XX

Ge(111)-c(2x8)

Raster scan

Slow

scan

Fast scan

c d e f g h

CrystalCrystalAxisAxis

k=33.2N/m=>∆Z=0.2nN/33.2N/m~6pm6pm

Lateral Scan MethodLateral Scan Method

Direction of slow scan:Imaging set point at FarFar distance ∆f = - –28 Hz => -0.8 nNWeak Weak attractive force

NonContactNonContact ImageImage::Direction of slow scan:Imaging at nearnear (closer) distance∆f = –31 Hz => -1.0 nNStrong Strong attractive force

NearContactNearContact ImageImage::

b

N. Oyabu, Y. Sugimoto, M. Abe, O. Custance, and S. Morita, Nanotechnology, 16 (2005) pp.S112–S117.

[110]

Straight Walk

33

Low Temperature 78K

Lateral manipulation of single atoms with NC-AFMLateralLateral manipulation of manipulation of single atomssingle atoms with with NCNC--AFMAFM

Ge(111)-c(2x8) Raster scan

Slow

scan

Fast scan

Lateral Scan MethodLateral Scan Method

CrystalCrystalAxisAxis

Before Lateral Before Lateral ManipulationManipulation

NonContactNonContact AFM ImageAFM Image[110]

Zigzag WalkZigzag Walk of Adsorbed Atom of Adsorbed Atom by Lateral Manipulationby Lateral Manipulation

NearContactNearContact AFM ImageAFM Image

34

(6)(6) Atom Inlay at RTAtom Inlay at RT

Assembly Assembly of of NanostructureNanostructurefrom from Two Atom SpeciesTwo Atom Species

Yoshiaki Sugimoto, Masayuki Abe, Shinji Hirayama, Noriaki Oyabu, Oscar Custance and Seizo Morita; “Atom inlays performed at room temperature using atomic force microscopy”, Nature Materials, vol. 4, issue 2 (2005) pp.156-159.

N.Oyabu, Y.Sugimoto, M.Abe, O.Custance and S.Morita; “Lateral manipulation of single atoms at semiconductor surfaces using atomic force microscopy”, Nanotechnology 16 (2005) pp.S112–S117.

SnSn GeGe @RT@RT

Yoshiaki Sugimoto, Óscar Custance, Masayuki Abe and Seizo Morita; “Site-Specific Force Spectroscopy and Atom Interchange Manipulation at Room Temperature”, e-Journal of Surface Science and Nanotechnology (e-JSSNT), Vol.4 (2006) pp.376-383.

35

Ge(111)-c(2x8)RTRTRaster Raster

ScanScan

Lateral Atom Interchange Manipulation Using Near-Contact AFM

LateralLateral Atom Interchange Atom Interchange Manipulation Manipulation Using Using NearNear--Contact AFMContact AFM

NearContactNearContact AFM ImageAFM ImageNonContactNonContact AFM ImageAFM Image

∆f=-7.2Hz

SnSn①②

∆f=-7.0Hz

∆f=-7.0Hz ∆f=-7.0Hz

(a) (b) (c)

[110]

NonContactNonContact AFM ImageAFM Image

NonContactNonContact AFM ImageAFM Image

CrystalCrystalAxisAxis

36

A B C

D E F

G H I

Sequence of topographic NC-AFM images acquired during the process of rearranging single atoms for constructing the symbol associated with the Tin element by successive well-controlled lateral manipulations of tin adatoms embedded within the plane of the Ge(111)-c(2x8) surface using NC-AFM technique. (A) Initial surface template for performing the manipulation experiment. (B) to (H) several intermediate stages creating the letters and cleaning the surrounding region by manipulating adatoms one by one. A fixed substitutional Sn adatom during the whole construction process is indicated by an arrow as reference. (I) Letters of the symbol associated with the Tin element. Image size was 7.7x7.7 nm2. The images were performed with a cantilever oscillation amplitude value of 157 Å, using a Si cantilever of 29.5 N/m measured spring constant, at a frequency shift values of –4.7 Hz (A), –4.4 Hz (B and C), –4.2 Hz (D), –4.0 Hz (E, G, and H), –4.1 Hz (F) and –4.6 Hz (I), with respect to a free oscillation first mechanical resonant frequency value of 160.450 kHz.Within near 9 hours more than 120 single atom lateral manipulations.

Process of Process of NanostructuringNanostructuring of Atom Inlayof Atom Inlay

Y. Sugimoto, M. Abe, S. Hirayama, N. Oyabu, O. Custance, and S. Morita, Nature Materials, vol. 4, issue 2 (2005), pp.156-159.Successive Imaging and Following Lateral Atom ManipulationSuccessive Imaging and Following Lateral Atom Manipulation@RT@RT

37

Atom Letters -Preceding and Present Achievements-Atom LettersAtom Letters --Preceding and Present AchievementsPreceding and Present Achievements--

NiNi

XeXeIBMIBMAdsorbedAdsorbed AtomAtom

MoMoSS

HCRLHCRLVacancyVacancy

SnSn

GeGeSnSn

Embedded AtomEmbedded Atom

Atom Inlay [Embedded Atom Letters] Atom Inlay [Embedded Atom Letters]

Single ElementSingle Element: : XeXe AtomAtom

STMSTM

4 K4 K

Single ElementSingle Element: S Vacancy: S Vacancy

STMSTM

RTRT

1990

1991

Two ElementsTwo Elements: : SnSn and and GeGe AtomsAtoms

AFMAFM

RTRT

2005 (Our ResultOur Result)

IBM Almaden

Hitachi Central Research Lab.

Osaka University

D.M. Eigler & E.K. Schweizer, Nature 344, 524 (1990)

S.Hosoki, S.Hosaka and T.Hasegawa, Appl.Surf.Sci.60/61, 643 (1992).

Y.Sugimoto et al., Nature Materials, vol. 4, issue 2, 156 (2005).

38

MovieMovie:: 9 hours with 120 times of lateral atom manipulation 9 hours with 120 times of lateral atom manipulation @ RT@ RTEmbedded Atom Letters Figured by NC-AFMEmbedded Atom Embedded Atom LettersLetters Figured by Figured by NCNC--AFMAFM

Y. Sugimoto, M. Abe, S. Hirayama, N. Oyabu, O. Custance, and S. Morita, Nature Materials, vol. 4, issue 2 (2005), pp.156-159.

GeGeAtom

EmbedEmbedded ded SnSnAtom

AFMTip

Tip induced directional Tip induced directional thermal diffusionthermal diffusion

Tip Induced Directional Tip Induced Directional InterchangeInterchange of of SnSn and and GeGe

adatomsadatoms

GeGe AtomAtom

SnSn AtomAtom

How to use the How to use the vectorvector scan?scan?

39

““Atom InlayAtom Inlay””: : Embedded Atom Embedded Atom LettersLetters Figured by Figured by NCNC--AFMAFM

SnSn AtomAtom GeGe AtomAtom @RT

Sn/Ge(111)-c(2x8)

4020052000 20102015

2003 Extraction and deposition of Si adatomon Si(111)7×7 by vertical atom manipulation: 78K

2006 Vertical atom-interchange manipulation: RT

Multi atom species

Single atom species

2012 Assembly of atom device using 3 atom species

2006 Atom manipulation on insulating surface

Mechanical Atom Manipulation by AFMMechanical Atom Manipulation by AFM

2005 Lateral atom manipulation of single adsorbed atom on Ge(111)-c(2×8): 80K

2005 Lateral atom-interchange manipulation of Sn and Geadatoms and “Atom Inlay” in Sn/Ge(111)-c(2×8): RT

2006 Lateral atom manipulation in 3 atom species sample

2015 Assembly of atom cluster using 3 atom species

2020 Assembly of molecule using 2 atom species

2008Atom manipulation in gas

2009 Atom manipulation in liquid

2010Assembly by atom manipulation in gas

2011 Assembly by atom manipulation in liquid

Achieved

Achievable

Indeterminate

“Now” “5 years later” “10 years later” “Further”“5 years ago”

YearYear

41

(1) Chemical Identification of atom speciesChemical Identification of atom species.(2) Mechanical Atom Manipulation at LT/RTMechanical Atom Manipulation at LT/RT.

⇒ It can cut and form covalent bond.

⇒ It can identify chemical species.

Here, we demonstrated three topics:

(3) Atom Inlay at RTAtom Inlay at RT.Assembly Assembly of of NanostructureNanostructure from from Two Atom SpeciesTwo Atom Species

SiSiInIn

SiSi InIn

SiSiSiSiInIn

Cantilever

InIn

Deflection

Displacement sensor

SelectiveSelectivemanipulation/

assembly

Evaporation of many atom species many atom species

TipTip

Chemical Chemical IdentificationIdentification

Displacement sensor

Cantilever Deflection

Many atom speciesMany atom species Novel Novel nanomaterialnanomaterial/Novel /Novel nanodevicenanodevicewithwith Novel functionNovel function NanoNano--AlloysAlloys

NanoNano--DevicesDevices