Fundamental Aspects on Thin Film Growth · Film Growth Techniques Characterization Conclusion *...

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation

Basic Kinetic Description

Growth

Epitaxy

Film Morphology

Film Growth Techniques

Characterization

Conclusion

Fundamental Aspects on Thin Film Growth Fernando Stavale

Scanning Probe Spectroscopy Group Department of Chemical Physics

Fritz-Haber Institut

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion * H.-J. Freund, Surface Science 500 271 (2002) - Clusters and islands on oxides: from catalysis via electronics and magnetism to optics

** J. T. Yates et al,Chem. Rev. (2012) - Band Bending in Semiconductors: Chemical and Physical Consequences at Surfaces and Interfaces

Chemistry* Electronics* Optics**

Ruby

Cr:Al2O3

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Chemistry: heterogeneous catalysis*

*H.-J. Freund, Surface Science 500 271 (2002) - Clusters and islands on oxides: from catalysis via electronics and magnetism to optics ** Prof. Dr. Jörg Libuda, Y. Sun, Doctor Thesis (2010),

**

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Electronics: gas sensor*

* H.-J. Freund, Surface Science 500 271 (2002) - Clusters and islands on oxides: from catalysis via electronics and magnetism to optics ** J. T. Yates et al,Chem. Rev. (2012) - Band Bending in Semiconductors: Chemical and Physical Consequences at Surfaces and Interfaces

**

**

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

• removal of NO, NO2, and N2O (DeNOx Process)

• removal of SO2 (DeSOx Process)

• promotion of methane activation

•

Chemistry: Enhanced adsorption energy *

Cr 3d

*J. A. Rodriguez et al, J. Phys. Chem. B 105 5497 (2001) ** Philip Myrach, Doctor Thesis (2010)

**

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

* J. T. Yates et al,Chem. Rev. (2012) - Band Bending in Semiconductors: Chemical and Physical Consequences at Surfaces and Interfaces

Chemistry + Optics: Photocatalysis or Photochemistry*

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Stra

in m

aps

Modifying the adsorption behavior*

STM images Metal adsorption: Iron and Chromium

* Stavale et al, Adv. Func. Mat. (2012) - Steering the growth of metal ad-particles via interface interactions between an MgO and Mo support

MgO (001)

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Tailoring the Physical and Chemical Properties of Oxides*

*Stavale et al, J. Am. Chem. Soc. 134 11380 (2012)-Donor Characteristics of Transition-Metal-Doped Oxides Cr-MgO vs. Mo-CaO

Cr+3

do

pe

d M

gO

Mo

+2,+

3 d

op

ed

CaO

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

LaAl3O/SrTiO3 interface

LaAlO3

D. G. Schlom, J. Mannhart, Nature Materials 10 168 (2011) - Oxide electronics: Interface takes charge over Si M.L. Reinle-Schmitt, Nature Communications 3 932 (2012) - Tunable conductivity threshold at polar oxide interfaces

SrTiO3

cross-section TEM micrograph

Polar interface induces electronic reconstruction

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Nucleation and the Early Stages of Film Growth

→ Adsorption (physisorption) → Surface diffusion → Chemical bond formation (chemisorption) → Nucleation → Microstructure formation → Bulk changes

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Growth modes

Volmer-Weber mode: small clusters are nucleated directly on the substrate surface and then grow into islands of the condensed phase. atoms (or molecules) of the deposit are more strongly bound to each other than to the substrate.

Frank-van der Merwe mode: displays the opposite characteristics. atoms are more strongly bound to the substrate than to each other, the first atoms to condense form a complete monolayer on the surface.

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

In Stranski-Krastanov mode after forming the first monolayer subsequent layer growth is unfavourable and islands are formed on top of this ‘intermediate’ layer. There are many possible reasons for this mode to occur, and almost any factor which disturbs the monotonic decrease in binding energy, characteristic of layer growth, may be the cause. For example, the lattice parameter of, or symmetry of, or molecular orientation in, the intermediate layer may not be able to be continued into the bulk crystal of the deposit. This results in a high free energy of the deposit intermediate-layer interface which favours subsequent island formation.

Growth modes

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

An approaching atom can either be reflected or absorbed on to the surface of the substrate and the process is dependent on the incoming flux of atoms the trapping probability the sticking coefficient

Ephysi ~ 0.25 eV Echemi ~ 1 - 10 eV

Rates are thermally activated

(Arrhenius law)

Adsorption: Physisorption → Chemisorption or desorption

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

The overall surface energy can be minimized if the atom has enough energy and time to diffuse to a lower energy site. Obviously, the diffusion rate increases with temperature, and is defined as

Driving force for Surface Diffusion

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

activation energies (Eadsorption, Ediffusion, Enuclei) and frequency factors.

two independent experimental variables (Rate, Temperature) which together form the main way to tune the system

Activation Energies

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

For vapor deposition from an ideal gas at pressure p, the rate of arrival J at the substrate is given by

by a molecular beam or evaporation source, or by arrival of ions from solution.

(Hertz-Knudsen equation)

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Thermodynamic Descriptions: Surface Energy

In equilibrium a system consisting of N particles at fixed T

where the Helmholtz free energy is given by

and U given by the first and second law of thermodynamics

F is minimum in the equilibrium and G is minimum for constant T, P and N

Kramers Grand potential

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

solid vapor

two homogenneous bulk phases and one surface plane

the surface contribution to the potential should be proportional to the area

or

surface energy versus surface tension

plastic deformation = increase number of atoms keeping area

elastic deformation = keep number of atoms change atomic distances

surface stress tensor

Thermodynamic Descriptions: Surface Energy

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Should all Surfaces be Reconstructed? Dieter Wolf, PRL 70 627 (1993)

The surface tends to change the atomic density in order to equals the surface tension and surface energy terms

Si(111)-7x7

Surface Energy versus Surface Tension

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

bs is the energy per step

Polar (Wulff) plot

Surface Energy

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Surface Energy

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Surface Energy: faceting and roughing

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

The basis of the theorem is that for a given volume, the equilibrium shape must be determined by minimizing the total surface free energy. The ensuing theorem states that the ratio between the real-space distance di from the cluster center to the facet plane i and the surface energy g of this facet is a constant:

G. Wulff, Z. Kristallog., 34 (1901), p. 4491 Palladium Nanocrystals on Al2O3: Structure and Adhesion Energy, M. Bäumer,H.-J. Freund, F. Besenbacher, I. Stensgaard et al. PRL 83 4120 (1999)

Surface Energy: Equilibrium Crystal Shape

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Palladium Nanocrystals on Al2O3: Structure and Adhesion Energy, M. Bäumer,H.-J. Freund, F. Besenbacher, I. Stensgaard et al. PRL 83 4120 (1999)

Surface Energy: Equilibrium Crystal Shape

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Chemical Potential

Oxidation-induced change of Gibbs free energy ∆G (eV) of the FeO/Pt(111) film as a function of oxygen chemical potential (eV)

S. Shaikhutdinov, G. Pacchioni, and H.-J. Freund, J. Phys. Chem. C, 2010, 114 (49), pp 21504

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

The free energy associated with the formation of a solid spherical cluster in an otherwise homogeneous fluid is

where γ is the interfacial energy per unit area. An expression for the critical cluster size r* is obtained by setting the derivative d(G)/dr = 0 and solving to yield

Substituting r* into yields the nucleation activation barrier:

Homogenous nucleation

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion


Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

a step further (using 1st and 2nd laws)

and now ideal gas law,

0.07ML Fe on Fe(001) at (a) 20, (b) 108, (c) 163, (d) 256, (e) 301, and (f) 356 C

Similarly, r* also increases with decreasing flux


Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

TEM of Au clusters on NaCl(001) at 250C (a) 0.5, (b) 1.5, (c) 4, (d) 8, (e) 10, (f) 15, (g) 30, and (h) 85 minutes evaporation (flux 1×1013 cm−2 s−1 )

“can be homogeneous nucleation theory employed to describe the

heterogeneous nucleation, although its corresponds to the unrealistic case of nucleating a

spherical particle with a contact angle of 180◦ on a solid surface (i.e.

zero film/substrate interaction)”


Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

2D Fe cluster size distributions, j is the number of atoms per cluster and Nj is the number of clusters of size j, on Fe(001) as a function of the temperature


Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

“strongly size-dependent properties (e.g. reduced cohesive energies and melting points, increased vapor pressures, and the collapse of continuous densities of electronic states into discrete atom-like levels) also play a role on the nucleation description, and are precisely the reason why nanostructures are so interesting”

Nucleation of Nanostructures

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

gsurface-film

gsurface-vacuum

gfilm-vacuum

Heterogeneous nucleation

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Heterogeneous nucleation: Stranski-Krastanov mode and Quantum dots

Ge on Si(001)

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Heterogeneous nucleation: Anisotropic substrate

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion G. Ehrlich, F. G. Hudda, J. Chem. Phys. 44, 1039 (1966)

R. L. Schwoebel, E. J. Shipsey J. Appl. Phys. 37, 3682 (1966)

Ehrlich-Schwoebel barrier

Heterogeneous nucleation: step barrier

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

STM images of Ag islands on Ag(111): (a) adatom island and (b) vacancy island

K. Morgenstern, G. Rosenfeld, E. Lægsgaard, F. Besenbacher, G. Comsa, PRL 80 556 (1998)

Ehrlich-Schwoebel barrier

Heterogeneous nucleation: step barrier

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Kinetic Description: rate equations

“the essence of atomistic kinetics approaches is to simultaneously solve parallel rate equations for the change in number density Nj of clusters of size j. Neglecting coalescence, one can write ordinary differential equations to describe the time rate of change in the concentration of monomers, dimers, trimers, and higher order clusters on a substrate surface in response to an incident flux J of atoms”

impingement rate

desorption rate

dimer formation rate in which K1 is the rate constant

rate of monomer loss to higher order clusters.

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Kinetic Description: rate equations

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Nucleation regime → Growth regime

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Ag deposition onto Pt(1 1 1) at 75 K

“monomers meet each other and create dimers, resulting in trimers, and next dimers, trimers and a few tetramers, giving rise to the mean island size of about three atoms. Increasing the coverage further leads to the transition from nucleation to growth”


Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

0.1ML Ag onto Pt(1 1 1) at 50 K

“from a regime of constant island size to an exponential growth with annealing temperature one may expect 2D Ostwald ripening.” Ostwald ripening is caused by a more rapid dissociation of smaller islands in favor of larger ones.


Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

“The driving force for coalescence is a reduction in surface energy by curvature-driven diffusion causing the islands to become taller and more compact”

TEM images of coalescence of two Au islands on MoS2(0001) at 400 C


Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

TEM micrographs obtained during the growth and coalescence of In islands deposited on amorphous C substrates at Ts = 540 C


Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

STM images showing coalescence and subsequent reshaping of 2D TiN on TiN(111) at T = 873 C in N2


Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Homoepitaxy: material identical to the substrate Heteroepitaxy: different material

Epitaxy

Niklas Nilius, Surface Science Reports 64 (2009) 595

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

MgO/Mo(001) films of (A) 2 ML, (B) 10 ML and (C) 18 ML thickness

Niklas Nilius, Surface Science Reports 64 (2009) 595

Strain and dislocations

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Matthews–Blakeslee model

“above the critical thickness, there is a driving force of dislocation motion in the interface due to the lattice mismatch”

for h = hcrit, σt = σf

(σt restoring stress due to the line tension of the dislocation, σf stress due to the lattice mismatch)

H. S. Leipner, Interdisziplinäres Zentrum für Materialwissenschaften Martin-Luther-Universität Halle

Strain and dislocations

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Film Morphology

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Thin film growth techniques

Physical Vapor Deposition (PVD) Film is formed by atoms directly transported from source to the substrate through gas phase

Evaporation 1. Thermal evaporation 2. E-beam evaporation 3. Pulsed Laser Deposition Sputtering 1. DC sputtering 2. DC Magnetron sputtering 3. RF sputtering * Reactive PVD Chemical Vapor Deposition (CVD) Film is formed by chemical reaction on the surface of substrate

Low-Pressure CVD (LPCVD) Plasma-Enhanced CVD (PECVD) Atmosphere-Pressure CVD (APCVD) Metal-Organic CVD (MOCVD)

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

(Hertz-Knudsen equation)

Thin film growth techniques: Evaporation

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Clausius–Clapeyron relation characterizing a discontinuous phase transition between two phases of matter of a single constituent.

then using the ideal gas law


Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Vapor Pressures of selected elements


Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion


Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Thin film growth techniques: Pulsed Laser Deposition

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Thin film growth techniques: Sputtering (DC and RF)

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Thin film growth techniques: Magnetron Sputtering

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Thin film growth techniques: Chemical Vapor Deposition

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Thin film growth techniques: Thermal-Chemical Vapor Deposition

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Thin film growth techniques: Plasma enhanced-Chemical Vapor Deposition

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Thin film growth techniques: Laser assisted-Chemical Vapor Deposition

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

1. Reflection High Energy Electron Diffraction 2. Low Energy Electron Diffraction 3. Helium Atom Scattering 4. X-ray diffraction 5. Transmission Electron Microscopy 6. Scanning Probe Microscopy

Characterization of thin film growth

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Auger Electron Spectroscopy: growth mode

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Volmer-Weber (VW) Stranski-Krastanov (SK) Frank-van der Merwe (FM)

C. Aargile, G.E. Rhead, Surface Science Reports 10 (1989) 277

Auger Electron Spectroscopy: growth mode

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

AES measurements of (b) MoOx phase (d) oxidized molybdenum foil with (c) MoO2 and (d) MoO3

Horst Niehus et al Surface Science 587 (2005) 219

Auger Electron Spectroscopy: chemical composition

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

AES measurements of (a) the hexagonal NbOx phase (cf. Fig. 5); (b) the rectangular MoOx phase (cf. Fig. 6); (c) and (d) oxidized molybdenum foil with (c) MoO2 and (d) MoO3. The spectra are normalized on the height of the highest metal peaks Mo186 eV and Nb167 eV, respectively.

Horst Niehus et al Surface Science 587 (2005) 219

STM of MoOx phase on Cu3Au(100)–O

Scanning Tunneling Microscopy: phase structure

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

H. Niehus, W. Heiland, E. Taglauer, Surf. Sci. Rep. 17, 213 (1993)

Ion Scattering Spectroscopy: basic geometry

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

He+ ion scattering spectra obtained at the Cu(100) surface before and after of 0.5 ML Ir

G. Gilarowski, H. Niehus, Surface Science 436 (1999) 107

Ion Scattering and Auger Electron Spectroscopy: subsurface alloying

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Ultrathin film investigated by STM and AES/XPS

STM images

Stavale et al, Surface Science 603 2721 (2009)-Ultra thin V2O3 films grown on oxidized Si(111)

V2O3

Si(111)

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

* Stavale et al, Physical Review B 82 045408 (2010)-Signatures of oxygen on Cu3Au(100) From isolated impurity to oxide regimes

** Surface Science 587 219–228 (2005) Controlled preparation of well-ordered transition metal oxide layers on a metallic surface

STM images Cu3Au(001) * Cu3Au(001) model bare surface Oxygen-terminated

V2O3(0001)**

Low Energy Electron Diffraction

V2O3

Cu3Au

Ultrathin film investigated by STM and TEM

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Ultrathin film investigated by STM and TEM

Transmission Electron Microscopy (TEM) measurements

Stavale et al, Surface Science 602 L59 (2008)-Atomically resolved interface structure of a vanadium sesquioxide(0001)

V2O3

Cu3Au

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Vanadium oxide NPs

substrate

H2O

cooling in PH2O metal evaporation in PO2 metal-oxide NPs

Nanoparticles grown by Buffer-layer Assited Growth*

Transmission Electron Microscopy (TEM) measurements**

**F. Stavale, L. Gomes – DIMAT/INMETRO (2009) *J. H. Weaver et al, PRL 80 4095 (1998)

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

Model based on STM and LEED

STM image Cathodo-luminescence LEED patterns

*Stavale et al, (2012) submitted

** T. W.S. Yip, E.J. Cussen, C. Wilson Dalton Trans., 29 277 (2010) - Spontaneous formation of crystalline lithium molybdate

**

Lithium-molybdate surface investigated by STM and local CL*

LiMoO4

Introduction

Overview

Thermodynamic

Surface Energy

Nucleation


Growth

Epitaxy

Film Morphology


Characterization

Conclusion

More references:

Rep. Prog. Phys. 47 399 (1984)

Chem. Soc. Rev., 1, 445, (1972)

Rep. Prog. Phys. 71 016501 (2008)

Surfaces and Interfaces of Solid Materials , Springer (1998)

Fundamental Aspects on Thin Film Growth · Film Growth Techniques Characterization Conclusion *...

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