Single atom identification and manipulation using atomic force microscopy

Yoshiaki Sugimoto

GeSn

JST-DFG workshop on Nanoelectronics

Introduction

M. AbeAssociate Professor

S. MoritaProfessor

Japan

Osaka

O. CustanceVisiting Associate

Professor

Bottom-up nanotechnology

Invention of STMInvention of STM

R.P. Feynman R.P. Feynman

There's Plenty of There's Plenty of Room at the Bottom Room at the Bottom

1982 1982

T=5 K

CO molecule

Cu(111) surface

Atom manipulationAtom manipulation

The technology for atomThe technology for atom--byby--atom construction of atom construction of nanonano--devicesdevices

Logic gate constructedLogic gate constructedby atom manipulationby atom manipulation

A.J. Heinrich, et al., A.J. Heinrich, et al., ScienceScience 298298 (2002) 1381.(2002) 1381.

D.M. D.M. EiglerEigler, et al., , et al., NatureNature 344344 (1990) 524.(1990) 524.

19591959

G. G. BinnigBinnig H. Rohrer H. Rohrer

T=4 K

Ni(100) surface

Xe atom

Our approach

Using Atomic force microscopy (AFM)Using Atomic force microscopy (AFM)At room temperatureAt room temperatureEvaporation of

various atom species various atom species

Atom Atom ManipulationManipulation

Atom Atom IdentificationIdentification

At cryogenic temperatureUsing Scanning tunneling microscopy (STM)

PreviousPrevious atom manipulation and assemblyatom manipulation and assembly

Our approachOur approach

Outline

Atom imaging

Atom discrimination

Atom identification

Atommanipulation

At room temperature

A A AB

A A AB

Using AFM

Atom imaging

Atom discrimination

Atom identification

Atommanipulation

Atom imaging

At room temperature

A A AB

A A AB

Using AFM

Experimental setup

Commercial Si cantilever (Nano World)f0=160 kHz, k=30 N/m, Q=13000, A=20 nm (Typical values)Ar ion sputtering UHV

Top view

Side viewTop view of AFM unit

Base pressure

AFM images of various surfacesSi(111)-(7x7) Si(100)-(2x1) Ge(111)-c(2x8)

KCl(100)Pb/Si(111)-(1x1)

Metal

Semiconductor

Insulator

Si atom Si atom Ge atom

Atom discrimination

Atom identification

Atommanipulation

Atom imaging

Atom discrimination

At room temperature

A A AB

A A AB

Using AFM

Discrimination between Sn and Si atoms

Sn:50% Si:50% Sn:75% Si:25% Sn:99% Si:1%

SiSn

The amount of evaporated Sn atoms increases

Sn/Si(111)-(33)

Si surface

Sn atoms

The limitation of atom discrimination from image

SiIn

SbSi

In and Si Sb and SiSn and Ge

GeSn

Si, Sn, and Pb mixed surface

Only twoatomic contrasts?

More than threeatomic contrasts?

Atom identificationAtom

manipulation

Atom imaging

Atom discrimination

Atom identification

At room temperature

A A AB

A A AB

Using AFM

Atom identification based on force measurementSi, Sn, Pb mixed surface

SiSn Pb

Si

Si

Sn

Si

Pb

SiFSi-Si FSi-Sn FSi-Pb

The chemical bonding force between tip apex atoms and surface atoms can be measured by AFM.

The method for measuring the interaction force

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

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

f

[

H

z

]

f -2-1

0

1

2

3

Z[]0 2 4 6 8 10 12 14 16 18 20 22 24

-4

-3

F

[

n

N

]

FNumerical

Z[]

Totalcalculation

=A

A zAzzFdz

kAff

2220 )(

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

-2

-1

0

1

2

3

F

[

n

N

]

Z[]

FvdW

26ZRAF HvdW =

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

-3

-2

-1

0

1

2

3

F

[

n

N

]

Z[]

Subtraction

FShort=FTotal-FvdW

The chemical bonding force between tip apex atoms and surface atoms can be measured.

NC-AFM

-2 -1 0 1 2 3-3

-2

-1

0

1

2

F

[

n

N

]

Distance []

Si

Sn

We repeated force measurements using different tip apex states.

Different cantilevers

Different tip structure and compositionby intentional tip-surface contact

-2 -1 0 1 2 3-3

-2

-1

0

1

2

F

[

n

N

]

Distance []-2 -1 0 1 2 3

-3

-2

-1

0

1

2

F

[

n

N

]

Distance []-2 -1 0 1 2 3

-3

-2

-1

0

1

2

F

[

n

N

]

Distance []-2 -1 0 1 2 3

-3

-2

-1

0

1

2

F

[

n

N

]

Distance []-2 -1 0 1 2 3

-3

-2

-1

0

1

2

F

[

n

N

]

Distance []

SSnn

SiSi

The chemical bonding force: Sn and Si

Lateral precision: 0.1M. Abe, et al., M. Abe, et al., ApplAppl. Phys. . Phys. LettLett..

8787 (2005) 173503.(2005) 173503.

Atom tracking technique

Marked tip-apex dependence

-2 -1 0 1 2 3-3

-2

-1

0

1

2

F

[

n

N

]

Distance []-1 0 1 2 3

-2.0

-1.5

-1.0

-0.5

0.0

0.5

F

[

n

N

]

Distance []

Pb/SiPb/SiSn/SiSn/Si

SSnnSiSi

PbPbSiSi

5 sets by various tip states5 sets by various tip states

Absolute values of the chemical bonding force is uselessfor atom identification

Absolute values of the chemical bonding force strongly depend on the tip apex structure or composition.

Different force

-2 -1 0 1 2 3-1.0-0.8-0.6-0.4-0.20.00.20.40.60.81.0

F

/

F

S

i

(

S

e

t

)

Distance []

-2 -1 0 1 2 3-3

-2

-1

0

1

2

F

[

n

N

]

Distance []-1 0 1 2 3

-2.0

-1.5

-1.0

-0.5

0.0

0.5

F

[

n

N

]

Distance []

-1 0 1 2 3

-1.0

-0.8

-0.6

-0.4

-0.2

0.0

0.2

0.4

0.6

0.8

F

/

F

S

i

(

S

e

t

)

Distance []

Sn/Si Sn/Si relativerelative

interaction ratio:interaction ratio: 77%

Pb/SiPb/Si relativerelative

interaction ratio:interaction ratio: 59%

Averaged relative interaction ratioSn/SiSn/Si Pb/SiPb/Si

The The relative interaction ratiorelative interaction ratio of the maximum attractive chemical bonding forcesof the maximum attractive chemical bonding forcesfor the same tip for the same tip remains nearly constant independently on the tipremains nearly constant independently on the tip

SSnn PbPbSiSi

5 sets by various tip states5 sets by various tip states

SiSi

Finger

prints f

or the

single

atom i

dentific

ation

Atom fingerprints

Si Sn PbFSn FPbFSi

Si Sn PbFSn FPbF Si

FSn / FSi=0.77

FPb / FSi=0.59

FSn / FSi=0.77

FPb / FSi=0.59

-0.1 0.0 0.1 0.2 0.3 0.4 0.5 0.60

1

2

3

4

5

6

A

t

o

m

c

o

u

n

t

s

Topographic height []

1

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

2

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

3

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

4

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

5

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

6

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

7

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

8

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

9

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

10

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

11

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

12

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

13

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

14

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

15

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

16

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

17

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

18

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

19

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

20

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

21

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

22

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

23

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

24

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

25

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

26

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

27

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

28

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

29

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

30

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

31

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

32

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

33

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

34

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

35

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

36

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

37

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

38

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

39

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

0.0 0.4 0.8 1.2 1.6 2.0 2.401234567

A

t

o

m

c

o

u

n

t

s

Maximum attractive total force [nN]

77%59%

100%

Only 10 f(Z) averaged per force curve

-0.1 0.0 0.1 0.2 0.3 0.4 0.5 0.60

1

2

3

4

5

6

A

t

o

m

c

o

u

n

t

s

Topographic height []

Pb Sn Si

-1 0 1 2 3 4 5 6 7 8 9 10-2.5

-2.0

-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

-3 -2 -1 0 1 2 3 4 5 6 7 8-22-20-18-16-14-12-10

-8-6-4-20

f

[

H

z

]

Distance []

0.0 0.4 0.8 1.2 1.6 2.0 2.401234567

A

t

o

m

c

o

u

n

t

s

Maximum attractive total force [nN]

Pb Sn Si

Atom identification: Si, Sn, PbLow Si local chemical coordination

Y. Sugimoto, et al., Y. Sugimoto, et al., NatureNature 446446 (2007) 64.(2007) 64.

Only 10 f(Z) averaged per force curve

-2 -1 0 1 2 3 4 5 6 7 8-25

-20

-15

-10

-5

0

f

[

H

z

]

Distance []-0.1 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

0

1

2

3

4

5

6

A

t

o

m

c

o

u

n

t

s

Topographic height []

Pb Sn Si

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6012345678

A

t

o

m

c

o

u

n

t

s

Maximum attractive total force [nN]

Pb Sn Si

77%59%

100%

-1 0 1 2 3 4 5 6 7 8 9 10-1.5

-1.0

-0.5

0.0

T

o

t

a

l

f

o

r

c

e

[

n

N

]

Estimated tip-surface distance []

Atom identification: Si, Sn, PbHigh Si local chemical coordination

Y. Sugimoto, et al., Y. Sugimoto, et al., NatureNature 446446 (2007) 64.(2007) 64.

Atom manipulationAtom

manipulation

Atom imaging

Atom discrimination

Atom identification

At room temperature

A A AB

A A AB

Using AFM

Conventional lateral manipulation

Interchange lateral manipulation

Instrument STMOnly conductive surface

AFMAll surface

Method On top In plane

Temperature Cryogenic temperature Room temperature

Nanostructure

Ge atom Sn atom

New manipulation method

The direction of Sn migration is same as the scan direction.

Ge atomSn atom

Interchange lateral manipulation

Y. Sugimoto, et al., Y. Sugimoto, et al., Nature materialsNature materials 44 (2005) 156.(2005) 156.

The procedure of creatingatom letters at room temperature

The atom lettersA B C

D E F

G H I

Application to other systems

SiIn

SbSiSiSn

Sn/Si(111)-(33) In/Si(111)-(33) Sb/Si(111)-(77)

Interchange vertical manipulation

IInterchange lateral manipulationnterchange lateral manipulation IInterchange vertical manipulationnterchange vertical manipulation

Construction time: 9 hours

Conclusion and future plans

Atommanipulation

Atom imaging

Atom discrimination

Atom identification

At room temperature

A A AB

A A AB

Using AFM

Quantum wireQuantum wire

NanoclusterNanocluster

Quantum computerQuantum computer

A AB

BA

Single atom identification and manipulation using atomic force microscopy