Surface Engineering Nanostructures · Noble gases Bombardment (NG +): Ar , Kr, Xe Experimental: Ion...

Surface Engineering Nanostructures

Low energy Ion bombardment nanostructuring Process

Fernando Alvarez

Instituto de Física "Gleb Wataghin", Unicamp, 13083-970, Campinas, SP, Brazil

- Photo-lithography: Expensive, 100nm

- Scanning Beam Lithography: Low deposition rate, 10 nm

- Scanning Probe Lithography: Low deposition rate, 1 nm

Top Down: “Imposing” a pattern on the Substrate

Surface Engineering Nanostructures

1) Sculpted Substrate By Ion Beam Bombarding

2) Ni Self–organized Structures Obtained on the sculpted substrate

Ion BombardingTop–Down and Bottom-Up hybrid

- Resolution: 1nm

- One step process

- Large Areas

Bottom Up: Guiding the assembly of atoms or molecules

Bottom Up Fabrication: Mesoporous Patterned Silica (Sol Gel Technique)

J.J.S. Acuña, M.C. Marchi, F. Alvarez, Thin Solid Films 519 (2010) 214–217

• Silica Based Thin Film: cubic symmetry (polycondensation + evaporation+ self-organization )

• 7 nm cavities sizes separated by ~1.8 nm walls

• CVD Carbon Nanotubes Growth catalyzed by Ni

TEM-Cross Section SEM-Top View

Black dots: Ni catalytic decorated substrate

SEM-Top View

(b)

1W. K. Burton, N. Cabrera and F. C. Frank, Royal Soc., 243, 1950; D. Walton in Nucleation, Edited by A. Z. Zettlemoyer, Marcel Dekker, INC. NY, 1969; W. K. Burton , N.

Cabrera. And F. C, Frank, Phil. Trans. Roy Soc., London, A243, 302, 1951

Surface Process: a brief introduction

• Atoms arrive from the vapor phase

• Self-Organizing: Mean Way between kinetic and thermodynamic phenomenon

• Surface diffusion on a flat surface (terrace): primary mechanism (activated process)

• Mean displacement adatom : distance before remains immobilized or detaching to the vapor1

=0exp [ (s-us)/2kT]

s : evaporation energies

us : activation energy

Jumping

Detaching

F

• D/F>>1 Process Governed by Thermodynamic

(Near Equilibrium)

• D/F<<1 Process Governed by Kinetic

D= Diffusion Coefficient, F= Particles Flux

4

Surfaces nano-structuration

Navez, et al., C.R. Acad. Sci., 254 (1962)

First Experiments by Ion Bombarding

Valbusa et al., J of Phys: Cond. Mat. 14 (2002)

Glass, Ionized air, 6 hs, 4 kV

30°

0°

80°

5000 Å

5000 Å

5000 Å

Canhão

5

Campinas Sky, SP, Brazil

Snow Ripples Las Leñas, Argentina

Atacama Desert, Chile

6

Topography Accident: Sand and Snow

Sand(Snow) Dunes: At the hill or depression, Different Velocities

Clouds: ripples between the dry, cool air above and the moist, warm air

below

Small Velocity

WindHigh Velocity

Low energy Ion bombardment nano-structuring Process

Control Deposition Parameters

• Ion Species

• Ion Energy

• Impinging Angle

• Flux (Dose)

• Substrate Temperature

Noble gases Bombardment (NG +): Ar +, Kr, + Xe +

Experimental: Ion Beam

Energy

20 – 1200 eV

PO2 <10-8 mb

Current

~1mA/cm2

TARGET

SUBSTRATE

T Controlled

ION GUN 2

TURBO

PUMP

NG+

ION GUN 1

Ion gun

(Kaufman)

Ar, Xe+

In Situ

Photoelectron

Emission

Spectroscopy

TURBO

PUMP

SEM-FEG images: AISI 316L (Room T, Xe+, 1 keV)

•10Cucatti, Alvarez., ,submitted, 2014

Crystalline grains

evidenced

Patterns within the

crystalline grains

15º

Pattern

10

Nano-Structures on Semiconductors

500nm

GaSb, Gallium Antimonide

Facsko et al., Science 285,1999, p1551

Hexagonal Symmetry

Ar+, 2 KeV, perpendicular

Xe+, Si (110), 1keV, 15°Morales, Merlo, Droppa, and Alvarez, 2014, J. of. Phys: D

<0

01

>

<001>

11

Semiconductors Nano-structuration

Substrate: Si, Ar+, Room TemperatureIon energy dependence

Ziberi et al., J. Phys: Condens. Mat. 21 (2009)

800 eV 1200 eV 2000 eV

An

gu

loi:

15°

An

gu

loi:

20° 800 eV1200 eV 500 eV

12

Ion patterning: Bradley & Harper Model

ConvexConcave

M. Bradley and J. M. E. Harper, J. Vac. Sci. Technol. A, 6,4, 1988Faster Erosion

13

TiN + Ni Particles Ion Beam Deposition

Sputtering

gun

Turbo

pump

XPS

Carbon nanotubes grown by CVD, M. Morales,et al., JPhysD., 2013, 2013

Si

Nickel Particles

750°C

1.5 min deposition

5 min annealing

14

TARGET UHV

XPS

SUBSTRATE

T Controlled

ION GUN 2

TURBO

PUMP

NG+

ION GUN 1

Ion gun

(Kaufman)

Ar, Xe+

15

Ni Atoms Flux

Morales, Merlo, Droppa, Alvarez, J. of. Phys: D, 2014014)

Ion Gun

Vacuum

XPS

Annealing

750°C, 1.5 min , deposition

5 min annealing

Ni Deposition + Annealing

Fourier Transform

Atomic Force Microscopy

16Morales, Merlo, Droppa, and Alvarez, 2014, J. of. Phys: D

Conclusions

• Different possibilities generating regular nanostructures by ion

bombarding

• Self-organized metallic nano-particles on sculpted patterned silicon

• Self-organization: Irregularities & defects still important

• Lack of general theoretical understanding

about the general patterning

and self-organization process

Nitriding

Put a three years old black goat in a locked room, without food;

after the four day, feed the animal only with fern during two

days. The following night, put the goat in a vat with holes in the

button to collect the urine's goat. Store the urine of two or

three nights and throw out the goat. Therefore, temper yours

instruments in the collected urine.

Iron instruments are also very well tempered in the urine of a

young red haired boy, giving more hardening that tempering

simply in water.

Theophilus Presbyter (Roger of Helmarshhausen, Germany)

(Monge Beneditino, 12th Century),Scheme of Various arts,

translated to English from Hendrich, 1847.

Equipamentos e ProcessosEquipamentos e Processos

Instituto de Física “Gleb Wataghin”UNICAMP, SP, Brazil

Supporting Agency: FAPESP

Daniel Wisnivesky

Fernando Alvarez

Plasma-LIITS

Surfaces Plasma Processing

Gear Box Manufacturing

2004

Industrial

ApplicationsPlasma Nitriding

Industry

Small Company

Equipment and Processes

Equipamentos e ProcessosEquipamentos e Processos

• Metallic Surfaces treatments by plasma: R & D

• Equipment for nitriding and coatings: R & D

• Alternative to Salt Bath and Ammonia

• Interaction with the industry

PRIMARY COMPANY GOALS

Equipamentos e ProcessosEquipamentos e Processos

COMPANY EVOLUTION

PRODUCTS IN 2014

• Nitriding Equipments

• Pulsed Power Supply

• Hard Coating Equipments

• R&D: Processes and Equipments

• Industrial Consulting

• HiPIMS Equipments (High Power Impulse

Magnetron Sputtering)

Nitriding Plant Fully Automatic

Vacuum

Furnace Pulsed

Power Supply

CLP

Heater Control

Automatic Gas Console

Roll - to - Roll Thin Film Deposition

Solar Absorber Panels

Plasma Immersion (PI3) Nitriding System (25 keV)

+

Remote Auxiliary RF Plasma

Cooling

System

RF Generator

Pulsed PI3 Power

Reactor

Molds for Plastic Injection+Oxidation(P20, P50, H13)

Equipamentos e ProcessosEquipamentos e Processos

High Speed Steel Cutting Tools( M2, M35, M42)

0 20 40 60 80 100 120

Horas de uso

Cortador "Caracol"

Horas de uso

Nitretada

Equipamentos e ProcessosEquipamentos e Processos

Cold Work( D2, D3, D6)

Thanks for your attention

谢谢

32

33

34

35

36

37

38

39

40

41

42

43

Thanks for your attention

S. J. Liu et al. Appl. Phys. Lett., Vol. 80, No. 18, 6 May 2002

{111}{111}

Top View

Instability: Piling up along the terrace

Eb~ 0.45 eV

57

Ehrlich-Shhwoebel (E-S) barrier

Self - Organization

58

L

L0

L

L0

-s +s

Implanted layer (~5-10 Ǻ)

Bulk

Modified region (~1)

x-ray

penetration

depth

(~980nm)

Stress

0 100 200 300-550

-50

0

50

100

150

200

Initial compressive stress

Xe+

Kr+

Ar+

Str

ess (

MP

a)

Implantation Energy (eV)

Steel100Cr6(AISI 52100)

X-Ray diffractionSeeman-Bohlin

Replacement Collision Sequence (RCS)Newton Cradle (Momentum Conservation)

Shortcut to pendlots.lnk

Account for defects <10 nm depth*

Highly anharmonic localized excitations (such as a DB) which propagate

distances well beyond the ion penetration depth can explain deeper deffects+

* P. Hansen, Phys. Metal., 2003; + G. Abrasonis & W. Moeller, PRL,2006

61

1 m

1 Kv, X 25000

1.5 µm

1 Kv, X 25000

1 m

0.9 µm

SS316; T=390 0C, 4 hs

20 eV, Xe+ pre-bombardedSS316; T=390 0C, 4 hs

Without pre-bombardment

Nitrided Case : SS 316

62

38 40 42 44 46 48

N(200)

(111)

N(111)

No Bombarded Nitrided 4 hs

Inte

nsid

ade

, u.a

.

2, Grauss

50 eV Xe+ Bombarded & Nitrided 4 hs

300 eV Xe+ Bombarded & Nitrided 4 hs

Grazing X-Ray Diffractograms

Pre-Bombarded and Nitrided SS316

X-Ray Penetration depth ~0.15-0.20 m

= 1.5 4056 Å

Bragg-Brentano

63

35 40 45 50

0.0

0.5

1.0

T= 400 0C, 30

2(degree)

Inte

nsity (

arb

.units)

Xe++ Nitrided

Kr++ Nitrided

Ar++ Nitrided

Only Nitrided

+'(

´

=20 grazing angle

Grazing X-Ray Diffractograms

Pre-Bombarded and Nitrided AISI 4140

X-Ray Penetration depth ~0.15-0.20 µm

3 KV, Xe+

= 1,54056 Å

Bragg-Brentano

64

Difussion Coefficient

Polycrystalline multiphase system , `,

From the Phase diagram Fe-N: C´s

Diffusion

coefficient

I=Without

Pre-

treatment

II=With Pre-

treatment

Ratio

II/I

Dε (µm2/s) 0.88x10-4 3.7x10-44.6

D´ (µm2/s) 3.4x10-4 6.9x10-4

2

D (µm2/s) 0.32 0.32 1

Faster diffusion

Grain border, dislocations

Lower packing density

“Irrigation channel”

Adapted from

P. Hansen, Phys. Metal., 2003

Nitrogen Concentration

0 500 1000 1500

10

20

30

0 5 10 15 20 25 30

4

6

8

10

12

14

Ha

rdn

ess,

GP

a

Nitrogen content, at. %

Only nitriding (0.5 hr)

Xe+ pre-treatment (125 eV)

+ nitriding (0.5 hr)

Nitro

ge

n c

on

ten

t, a

t. %

Depth, nm

Sputtered Neutral Mass Spectroscopy

AISI 4140, 400 0C

65

Conclusions

•Implantation (knock-on) Xe+, Kr+, Ar+: stress

•Atomic Attrition: nanoscopic scale grain refining

Thanks for

your

attention

•Increasing Nitrogen Retention at Surface

•Improving Nitrogen Diffusion: thicker case

•Decreasing process time

•Thermal spike: relaxation

•Sequential Collision Effect

•Deeper changes due to other effects: e.g.: DB

•Increasing effective diffusion coefficient

•(–

66

67

ESTUDO DA NANOESTRUTURAÇÃO DE

SUBSTRATOS CRISTALINOS ATRAVÉS DO

BOMBARDEAMENTO COM FEIXE DE ÍONS A

BAIXA ENERGIA

Mónica Morales Corredor

Orientador: Prof. Dr. Fernando Alvarez

Exame de Qualificação de Doutorado

Campinas, abril de 201476

Sumário

77

Motivação

Métodos

Exemplos de Nano-estruturação de superfícies

Modelo do Bombardeamento com feixe de Íons

Experimento

Perspectivas

77

Sumário

78

Motivação

Métodos

Exemplos de Nano-estruturação de superfícies

Modelo do Bombardeamento com feixe de Íons

Experimento

Perspectivas

78

Parâmetros envolvidos

Temperatura

Substrato

Ângulo de

bombardeamento

Tipo de íons

Energia de

bombardeamento

Fluência

Interação de átomos

energéticos com a

superfície

Sputtering

79

Nano-estruturação de superfícies- BFI

Diversidade de nanoestruturas

formadas79

Nano-estruturação de Metais

Temperature Dependence

80

Ag (110), Ângulo: 0° t:15 min Gás: Ar Eí: 1 keV

160 K 230 K 270 K

290 K 320 K350 K

Rusponi S, et al. Phys. Rev. Lett. 78 (1997)

80

Nano - structuration of metals

81

Valbusa, J. of. Phys: Cond. Mat. 14,

(2003)

Substrates

180 K, 70°, 10 min, Ar+ , 1 keV

Ag(001) Cu(110) Ag(110)

81

Nano - structuration of metals

Bombarding Angle

Cucatti S, Alvarez F Mat. Chem. Phys (2014), Submitted

Policrystal

φ =15º φ = 45º

φ = 60º

0 15 30 45 600

5

10

15

20

25

Ru

go

sid

ad

e R

MS

(n

m)

ângulo de incidência (graus)

Amostra polida (<1.5 nm)

SS316L: Room Temperature, 15°, 30min, Xe+, 1keV

82

Nano-estruturação de

semicondutores

Fluência

83

Si

Ge

Cornejo, dissertation (2011)

Substrato: Si Gas: Kr

Ei: 2 keV Angulo

=3.4x1017íons cm-2 =1.1x1018íons cm-2

=6.7x1018íons cm-2 =1.3x1019íons cm-2

AFM

83

Sumário

84

Motivação

Métodos

Exemplos de Nano-estruturação em superfícies

Modelo do Bombardeamento com feixe de Íons

Experimento

Perspectivas

84

Bombardeamento com feixe de íons

85

Íon

incidente

migrante

sputtering

Implantação

fase

Amorfa

~2 nm

Sputtering (curvatura

Mecanismos de difusão

85

86

Bombardeamento com feixe de íons

Sputtering Yield

Emm

mm

UY

ti

ti

2

0

2 )(

4

4

3

+

s(E)- stopping power~1 keV

i

t

m

moU Surface binding energy

Teoria de Sigmund Phys. Ver, 184 (1969)

86

87

Bombardeamento com feixe de íons

Sputtering Yield

87

Bombardeamento com feixe de íons

Sputtering Yield

8888

Bombardeamento com feixe de íons

89

Modelo de Bradley and Harper – 2D

Rx > 0Rx < 0 Erosão mais rápidajDistribuição esférica

Rx

>> a

j=0 incidência

normala- Alcance médio de penetração dos

íons

J- Fluxo de íons incidentes

n-Densidade de átomos do substrato89

Modelo de Bradley & Harper- 3D

Bombardeamento com feixe de íons

90

Migração

dos

ripples

Difussão

superficial

adatomos

Taxa

erosão

superfície

plana

Sputtering

dependent

e da

cuvatura

Incidência não-normalz = h(x,y)

x

y

j

90

Longos tempos tem saturação e efeitos não lineares que não explica o modelo- Fluência.

Válido também para superfícies lisas.

Influência de impurezas

Outros modelos explicam os efeitos de ordem

maiores e não lineares.

91

Bombardeamento com feixe de íons

Falências do modelo B-H

91

Sumário

92

Motivação

Métodos

Exemplos de Nano-estruturação em superfícies

Modelo do Bombardeamento com feixe de Íons

Experimento

Perspectivas

92

Experimento

Motivação e Objetivo

AFM SEMSEM

Carpete de

nanotubos

alinhadosSubstrato nano-

estruturado

Barreira

Ilhas de níquel

9393

Experimento Resultados

94

Substrato: Si

Íons: Xe

Energia i: 500 eV

holes

Per. Ripp

SmoothHolesRipples Per.

Ziberi et al.

5° 10°

15° 20°

a b

c d<010>

<0

01

>

94

Experimento Rugosidade

95

5° 10°

15° 20°5 10 15 20

0,1

1

10

Ru

go

sid

ad

e R

MS

(n

m)

Ângulo de incidencia (°)

Si(100) polido

Xe+

Ziberi, 2009

0 10 20 30 40

0,1

1

10

Ru

go

sid

ad

e R

MS

(n

m)

Ângulo de incidencia (°)

Ar+

95

Experimento

9696

Sumário

97

Motivação

Métodos

Exemplos de Nano-estruturação em superfícies

Modelo do Bombardeamento com feixe de Íons

O experimento

Perspectivas

97

98

Fluxo de átomos de Ni Perspectivas

M Morales et al., J. of. Phys: D

(2014)

OBRIGADA!

99

Nano-Structures on Gallium Antimonide: Ar+ Ion Sputtering

Facsko et al., Science 285,1999, p1551

Hexagonal Symmetry

4x1017 cm-2, 40 s 2x1018 cm-2, 200 s 4x1018 cm-2, 200 s

500nm 500nm 500nm

GaSb

Fluences:5.2x1031/nm2;Tempo: 90 min and =37–43 nm

Au

~730Dual Ion Beam Sputtering, 2keV

101

Xe+ Patterning: Experiment

108

•Substrate

•Ion gun

•Turbo

•pump

Material: SS 316, Policrystal (austenite)

XPS

TiN + Ni Particles Ion Beam Deposition

Sputtering

gun

Turbo

pump

XPS

Carbon nanotubes grown by CVD, M. Morales,et al., JPhysD., Submitted, 2013

Si

Nickel Particles

750°C

1.5 min deposition

5 min annealing

132

136

Ni Atoms Flux

M Morales et al., J. of. Phys: D

(2014)

140

谢谢