Fabrication of Nano Structure

(1)

Nanomaterials

48

Fabrication of Nano Structure

Fabrication of Nano Structure - - assembly assembly

capillary force

- lateral capillary force deformation of liquid surface

6

1

2 1

for floating force ( ) for immersion force

( ) F R K R

F R K R σ

σ

⎛ ⎞

∝ ⎜ ⎟

⎝ ⎠

∝

1

: interfacial tension between air and liquid R: radius of particle

L: interparticle distance

K (R): modified Bessel function σ

two similar particles

light and heavy hydrophilic and hydrophobic

P.A. Kralchevsky, Curr. Opin. Colloid Interf. Sci. 6(2001) 383.

(2)

Nanomaterials

49

Fabrication of Nano Structure

Fabrication of Nano Structure - - assembly assembly

capillary force

- colloidal crystal multilayer, SiO

₂

alcosol

P. Jiang, Chem. Mater. 11 (1999) 2132.

(3)

Nanomaterials

50

Fabrication of Nano Structure

Fabrication of Nano Structure - - assembly assembly

capillary force

- patterned colloid deposition by electrostatic and capillary force

P. Jiang, Chem. Mater. 11 (1999) 2132.

(4)

Nanomaterials

51

Fabrication of Nano Structure

Fabrication of Nano Structure - - assembly assembly

Dispersion interaction

- gold nanocrystals (1.5~6 nm) capped with covalently bound linear alkylthiols

size dependence of van der Waals dispersional attraction between nanoparticles

P.C. Ohara, Phys. Rev. Lett. 75 (1995) 3466.

6

1

dispersion interaction at larger D at small D V D

V D

−

∝

P.C. Ohara, Angew. Chem. Inter.

Ed. Engl. 36 (1997) 1078.

(5)

Nanomaterials

52

Fabrication of Nano Structure

Fabrication of Nano Structure - - assembly assembly

Dispersion interaction

- self-organization of CdSe nanocrystallites into 3-D semiconductor quantum dot superlattice (colloidal crystals)

C.B. Murray, Science 270 (1995) 1335.

(6)

Nanomaterials

53

Fabrication of Nano Structure

Fabrication of Nano Structure - - assembly assembly

Shear force assisted assembly

- GaP, InP, Si NWs in ethanol solution

- passing suspension through fluidic channels formed between PDMA and a flat surface

Y. Huang, Science 291 (2001) 630.

(7)

Nanomaterials

54

Fabrication of Nano Structure

Fabrication of Nano Structure - - assembly assembly

Electric field assisted assembly

- Au nanowires

- electrically isolated electrodes - 1.0x10

⁴

~1.4x10

⁵

V/m

P.A. Smith, Appl. Phys. Lett. 77 (2000) 1399.

(8)

Nanomaterials

55

Fabrication of Nano Structure

Fabrication of Nano Structure - - assembly assembly

Electric field assisted assembly

- InP

D. Huang, Nature, 409 (2001) 66.

55

(9)

Nanomaterials

56

Fabrication of Nano Structure

Fabrication of Nano Structure - - assembly assembly

Covalently linked assembly

- Au and Ag

R. Griffith, Science 267 (1995) 1629. T. Vossmeyer, Angew. Chem. Int. Ed. Engl. 36 (1997) 1080.

(10)

Nanomaterials

57

Fabrication of Nano Structure

Fabrication of Nano Structure - - assembly assembly

Covalently linked assembly

- microcontact printing of Pd

- selective electroless deposition of Cu

P.C. Hidber, Langmuir, 12 (1996) 1375.

(11)

Nanomaterials

58

Fabrication of Nano Structure

Fabrication of Nano Structure - - assembly assembly

Template assisted assembly

- PS beads assembled in etched Si (100)

Y.Yin, J. Am. Chem. Soc. 123 (2001) 8718.

(12)

Nanomaterials

59

10nm

3-D Patterning Techniques

A) two photon polymerization in a polymer resist

B) holographic lithography in a polymer resist

C) photolithography with a gray-scale mask D) woodpile lattice fabricated

in a layer-by-layer fashion.

E) Opaline lattice of polystyrene beads

self-assembled between two flat substrates F) Silica inverse opal that was fabricated

by templating a sol-gel precursor against an polymer opaline lattice,

followed by selective removal of the beads.

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

Adv. Mater. 2000, 16, 1250

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Nanomaterials

60

10nm

Writing with a focused laser or electron beam

- carving of a surface by ablating the material with a focused beam in a serial manner - laser-induced deposition of precursor compound

- photoinduced polymerization of a liquid prepolymer

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

N. Barsch, Appl. Phys. A 77 (2003) 237. O. Lehmann, Science 270 (1995) 1644. B.G. Cumpston, Science 269 (1995)1078.

(14)

Nanomaterials

61

Writing with a focused laser or electron beam - Two-Photon Absorption (TPA)

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

Polymerization by the strong absorption of prepolymers

selective removal of unpolymerized precursors 3D-Patterning

S. Kawata, Nature, 412 (2001) 697.

B.H. Cumpston, Nature, 398 (1999) 51.

(15)

Nanomaterials

62

Two-Photon Absorption (TPA)

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

W. Zhou, Science, 296(2002)1106.

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Nanomaterials

63

10nm

Holographic patterning

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

- 2-beam interference patterns - 4-beam interference patterns

D. Kim, Appl. Phys. Lett. 66 91995) 1166. M. Campbell, Nature, 404 (2000) 53.

(17)

Nanomaterials

64

10nm

Holographic patterning

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

M. Campbell, Nature, 404 (2000) 53. S. Yang, Chem Mater. 14 (2002) 2831.

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Nanomaterials

65

10nm

Gray scale lithography

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

E.-B. Kley, Microelectron. Eng. 34, 261 Y. Oppliger, Microelectron. Eng. 23 (1994) 449.

(19)

Nanomaterials

66

10nm

Layer by layer fashion

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

J.A. Lewis, Materials Today, 7 (2004) 32.

(20)

Nanomaterials

67

10nm

Layer by layer fashion

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

G. M. Gratson, Nature, 428 (2004) 386.

(21)

Nanomaterials

68

10nm

Layer by layer fashion

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

D. Therriault, Nature Mater. 2 (2003) 265.

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Nanomaterials

69

10nm

Layer by layer fashion

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

S.Y. Lin, Nature, 394 (1998) 254. J.G. Fleming, Nature, 417 (2002) 52.

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Nanomaterials

70

10nm

Layer by layer fashion

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

S. Noda, Science, 289 (2000) 604.

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Nanomaterials

71

Colloidal Photonic Crystals- Opal

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

O.D.Velev, Curr. Opin. Colloid Interface Sci. 5 (2000) 56.

(25)

Nanomaterials

72

Colloidal Photonic Crystals- Opal

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

10nm

Experimental procedure to

fabricate colloidal photonic crystals:

aqueous dispersions of colloids injected into the cell

drying the cell

peeling off the top substrate

S.H. Park, Adv. Mater. 10 (1998) 1028.

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Nanomaterials

73

Colloidal Photonic Crystals- Opal

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

W.T.S. Huck, J. AM. Chem. Soc. 120 (1998) 8267.

(27)

Nanomaterials

74

Inverse Opals

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

O.D. Velve, Nature, 389 (1997) 447.

(28)

Nanomaterials

75

Inverse Opals

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

Y.A. Vlasov, Adv. Mater. 11 (1999) 165.

(29)

Nanomaterials

76

Inverse Opals

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

P.V. Braun, Nature, 402 (1999) 603.

(30)

Nanomaterials

77

Inverse Opals

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

A. Blanco, Nature, 405 (2000) 437.

(31)

Nanomaterials

78

Inverse Opals

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Patterning 3D Patterning

H.Miguez, Langmuir, 16 (2000) 4405.

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Nanomaterials

79

Fabrication of Nano Structure

Fabrication of Nano Structure - - quantum dot quantum dot

quantum dot

- GaAs/InGaAs/GaAs

- metalorganic vapor phase epitaxial growth in tetrahedral shaped recess (TRS)

Y. Sugiyama, Jpn. J. Appl. Phys. 34 (1995) 4384.

T. Sekiguchi, Appl. Phys. Lett. 83 (1998) 4944.

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Nanomaterials

80

Fabrication of Nano Structure

Fabrication of Nano Structure - - quantum dot quantum dot

quantum dot

- GaAs/InGaAs/GaAs

T. Sekiguchi, Appl. Phys. Lett. 83 (1998) 4944.

QD

QW

QD

QW

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Nanomaterials

81

Fabrication of Nano Structure

Fabrication of Nano Structure - - quantum dot quantum dot

quantum dot

- selective are MOCVD - GaAs/AlGaAs/GaAs

T. Fukui, Appl.Phys.Lett. 58 (1991)2018.

(35)

Nanomaterials

82

Fabrication of Nano Structure

Fabrication of Nano Structure - - quantum dot quantum dot

quantum dot

- selective area metalorganic vapor epixay

- AlGaAs/GaAs, SiN

_x

mask by photolithography and wet chemical etching

K. Kumakura, Jpn. J. Appl. Phys. 34 91995) 4387.

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Nanomaterials

83

Fabrication of Nano Structure

Fabrication of Nano Structure - - quantum dot quantum dot

quantum dot

- selective epitaxial growth on masked substrates by MOCVD

- mask- 20 nm thick SiO

₂

film with round windows, of which the diameter was

100 nm, made by plasma CVD, electron beam lithography, and wet chemical etching

- GaAs/Al

_0.4

Ga

_0.6

As/(100) GaAs

Y. Nagamune, Appl. Phys. Lett. 64 (1994) 2495.

(37)

Nanomaterials

84

Fabrication of Nano Structure

Fabrication of Nano Structure - - quantum dot quantum dot

quantum dot

- cleaved edge overgrowth (CED)-AlGaAs/GaAs by MBE

- localization energy of the exciton ground state wrt to the connected QW- 10 meV

M. Grundmann, Phys. Rev. 55 (1997) 4054.

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Nanomaterials

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Consolidation of nanomaterial

suppress the grain boundary migration enhance grain boundary diffusion

Two step sintering

I. W. Chen, Nature, 404 (2000) 168-171

Fabrication of Nanostructure

Fabrication of Nanostructure – – 3D Bulk 3D Bulk

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Nanomaterials

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(a) (b)

500nm 500nm

Temperature(^oC)

500 600 700 800 900 1000 1100 1200

Relative density(%)

70 75 80 85 90 95 100

SPS for 5 min.

SPS for 1h Normal sintering for 1 h

SPS (spark plasma sintering) fast heating rate

Nonocrysatlline TiO

₂

Y. I. Lee, Mater Res Bull., 38 (2003)925