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Combinaison quantitative GISAXS et STM: un outil pour sonder les interfaces enterres. E xemple du Co/ Au(111). O.Fruchart, Laboratoire Louis Nel (CNRS), Grenoble G. Renaud, M. Noblet, O. Ulrich ! DRFMC/SP2M/IRS (CEA), Grenoble J.-P.

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SLIDE 1

11/ 10 / 2 0 0 2

Laboratoire Louis Néel. Laboratoire Laboratoire Louis Néel. Louis Néel.

http:/ / lab- neel.grenoble.cnrs.fr/ them es/ couches/ ext/ http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Combinaison quantitative GISAXS et STM: un outil pour sonder les interfaces enterrées. E xemple du Co/ Au(111). O.Fruchart,

Laboratoire Louis Néel (CNRS), Grenoble

  • G. Renaud, M. Noblet, O. Ulrich

DRFMC/SP2M/IRS (CEA), Grenoble

J.-P. Deville, A. Barbier, F. Scheurer, J. Mané-Mané

IPCMS (CNRS/ULP/ECPM), Strasbourg

  • V. Repain, G. Baudot, S. Rousset

GPS-Jussieu, Paris

!

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SLIDE 2

Olivier Fruchart - 11/10/2002

  • p.2

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

GISAXS : principle and set-up

In-plane / out-of-plane diffusion Probes size (H,d), shape,

correlations PRINCIPLE

GISAXS: Grazing Incidence Small Angle X-ray Scattering

TECHNICAL ASPECTS

  • ID32 beamline at ESRF
  • In-situ under UHV:

real time background substraction

  • No window before sample : low background

Objects > > atom s Surface sensitive

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SLIDE 3

Olivier Fruchart - 11/10/2002

  • p.3

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

GISAXS : lateral information

  • M. Schm idbauer et al., PRB58, 10523 (1998)

Si1-xGex islands

Ex situ GI SAXS on self- assem bled dots : lateral inform ation

Information on dots shape and

lateral order.

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Olivier Fruchart - 11/10/2002

  • p.4

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

GISAXS : depth information

Pd/ MgO(001) islands

Ex situ GI SAXS on self- assem bled dots

  • G. Renaud et al., unpublished
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Olivier Fruchart - 11/10/2002

  • p.5

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

3D self-organization : effect of corrugation

TEM cross-section (Sequential sputtering)

Co/ Al2O3 granular system (sputtering)

(Co: 0.7 nm/Al2O3:3 nm)14

  • D. Babonneau, Appl. Phys. Lett. 76, 2892 (2000)

Co-sputtering Sequential sputtering RECIPROCAL SPACE GISAXS:

Grazing Incidence Small Angle X-Ray Scattering

FCC vertical stacking (not epitaxial !)

REAL SPACE

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Olivier Fruchart - 11/10/2002

  • p.6

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Au(111) > Basic s x √3 reconstruction

Site B Second layer atoms Site A Atoms of the topmost layer Site C Bride position

(smaller diameter for clarity only)

Cross-sectional view

A A A A B B C C C C C C C C C C C B B B B B B B B B B B B B B B B A A A A A A A A A A A A A A A A

fcc : ABC hcp : ABA Corrugation 50 x 28 nm

FCC HCP Z O O M

Planar view of Au(111)

FCC HCP

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SLIDE 7

Olivier Fruchart - 11/10/2002

  • p.7

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Au(111) > secondary ‘chevron’ reconstruction

250 x 250nm

  • J. V. Barth et al., Phys. Rev. B 4 2 ( 1 5 ) , 9 3 0 7 ( 1 9 9 0 )

Corrugation ~ 0.2 Å Unit cell size : ~ 7.5 x 25nm

A.R. Sandy et al., Phys. Rev. B 4 3 ( 6 ) , 4 6 6 7 ( 1 9 9 1 )

Isotropic surface relaxation

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Olivier Fruchart - 11/10/2002

  • p.8

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Au(111) > A template for self-organization

(0.20AL Co@300K)

Fe, Ni : 1 AL-high dots

5 10 15 20 0.1 0.2 0.3 0.4

2Co nm nm

350 x 350 nm

See also: D.D. Cham bliss et al., PRL 66, 1721 ( 1 9 9 1) B.Voigtlander et al., PRB 4 4 , 1 0 3 5 4 ( 1 9 9 1 )

FACTS: Co, Ni, Fe, Cu, Rh growth on Au(111) gives rise to self-organized arrays of dots ORIGIN ?

Co : 2 AL-high dots

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Olivier Fruchart - 11/10/2002

  • p.9

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Au(111) deposits > nucleation stage

J.A.Meyer et al., Surf.Sci.365, L647 (1996)

Fe, Co, Ni (etc.) nucleation: atomic place exchange mechnism with Au atoms

Example: 0.002ML Ni@ 300K

Leading parameter (?): deposit has a higher surface energy. (and Au atoms stress near chevrons)

0.25ML Ni @300K : 1ML-high dots

  • W. G. Cullen et al., Surf. Science 420, 53 (1999)

See also: S. Rousset et al.

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Olivier Fruchart - 11/10/2002

  • p.10

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Au(111) deposits > continuous films Continuous film s

  • J. Pommier el al., Phys. Rev. Lett. 65, 2054 (1990)

t > 2 AL Continuous film s t > 5- 7 AL Perpendicular m agnetic anisotropy

  • M. Speckm ann et al., Phys. Rev. Lett. 75, 2035 (1995)

M

Etc.

From dots to film s

  • S. Padovani et al., Phys. Rev . B 59, 11887 (1999)
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Olivier Fruchart - 11/10/2002

  • p.11

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

GI SAXS : inter- and intra-row order

q CCD INTRA-ROW ORDER: SUPER-CRYSTAL

Thickness: 1 Å ; coverage: 25%

? 4p/ ?

∆Q/ Q= 3%

q INTER-ROW ORDER: LIQUIDE-TYPE

2? 4p/ ?

Κ= 8.5nm σ= 2.1nm

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Olivier Fruchart - 11/10/2002

  • p.12

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

GISAXS : similarity with RHEED ?

Ordered sample ‘super’ reciprocal space ? Grazing incidence and 2D detector

similarity with RHEED

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Olivier Fruchart - 11/10/2002

  • p.13

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

GI SAXS on Co/ Au(111) : « crystallography » on a three-fold textured super-crystal

3-fold symmetry of Au(111) crystal

3 ‘equivalent domains’

FFT 1.5µm x 1.5µm STM image

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SLIDE 14

Olivier Fruchart - 11/10/2002

  • p.14

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Co/ Au(111) « crystallography » : experimental GISAXS ‘reciprocal space’

Similar patterns and good understanding

Do we gain any new information from GISAXS ?

GISAXS FFT of STM

Transverse cross-section of a peak

234 236 238 240 242 244 246 248 250 400 450 500 550

Azimuth Position (a.u.)

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Olivier Fruchart - 11/10/2002

  • p.15

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

10 15 20 25 30 35 5 Rod intensity analysis (intra-row)

First order peak intensity Thickness ( Å) 5 10 15 20 1E-4 1E-3 0.01 0.1 Second / First order Thickness ( Å)

Maximum at 6Å = 3 atom ic layers ? Significant intensity for continuous film ? Weak intensity ? Intermediate minimum ?

Features to explain

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Olivier Fruchart - 11/10/2002

  • p.16

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Rod intensity : I2/ I1 minimum : dot shape factor

RATIO: Second / First order peak intensity

Deposition rate calibration

1 2 3 4

q Period within lines : 2 /

π Λ

Simple model of 1D coalescence

~2Å (d=Λ) ~0.5Å (d=Λ/2) ~0.1Å (d=0.23Λ) ~1Å (d=Λ/√2) WEAK COVE RAG E COALE SCE NCE First zero of dot form factor

Λ

d d d Intensity Periodicity dots form factor = x

  • S. Padovani et al.,

PRB6 1 , 7 2 ( 2 0 0 0 )

5 10 15 20 1E-4 1E-3 0.01 0.1

Thickness (Å) Thickness ( ) Å

1E-4 1E-3 1E-2 0.1 1 1 2 3

Measured Calculated

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Olivier Fruchart - 11/10/2002

  • p.17

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Rod intensity : crucial role of the dot shape factor

) (

dot Q

F

vanishes rapidly for ‘reasonable’ dot size

5 10 15 20 200 250 300 350 400 Thickness (Å)

Broad rod Narrow rod

a.u.

Peak position

Maximum displaced from 2π/ a

Peak m agnitude

5 10 15 20 1E-4 1E-3 0.01 0.1 Higher orders: weak intensity 2nd/ 1st order narrow peak Broad peak without shape factor (liquid order)

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SLIDE 18

Olivier Fruchart - 11/10/2002

  • p.18

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Rod intensity : more elaborated model

) (

dot Q

F ) (

row Q

F ) (

liq Q

F

Building brick : 1 dot Row of dots I nter- row liquid order Bessel functions, etc. Dirac planes

Shape factor Structure factor

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Olivier Fruchart - 11/10/2002

  • p.19

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Rod intensity: more elaborated model

(d)

ε

Pair correlation function

I nter- row liquid order

Analytical formula

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Olivier Fruchart - 11/10/2002

  • p.20

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Model: role of the structure factor

ε

Epsilon= 0.0Lambda Epsilon= -0.125Lambda Epsilon= 0.35Lambda Epsilon= 0.20Lambda

From side- centered to cell- centered… (peak position is affected)

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Olivier Fruchart - 11/10/2002

  • p.21

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

DeltaKappa= 0.15Kappa DeltaKappa= 0.2Kappa DeltaKappa= 0.05Kappa DeltaKappa= 0.10Kappa

Model: role of the disorder

From crystal to liquid (peak position affected at high Q)

ε

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Olivier Fruchart - 11/10/2002

  • p.22

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Model: physical outputs Peaks position

Close to origin: determined by cell size Far from origin: determined by structure factor

(two slits interference)

Peaks intensity analysis

Explains w eakness of I 2 / I 1 : disorder and cell ‘centering’ Knowledge of disorder > deduce centering

nm 5 . 1 5 . 2 ± = ε

(for 0.5 AL)

Perspective

Measure m any m ore peaks Full ‘crystallographic’ analysis

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Olivier Fruchart - 11/10/2002

  • p.23

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Rod intensity : is the model too simple ?

Qualitative agreement Quantitatively : maximum for higher

coverage

I s the m odel too sim ple ? Does the roughness vanish at

coalescence ?

10 15 20 25 30 35

Thickness (Å)

5

Integrated intensity (a.u.) Thickness ( ) Å

1 2 3

Calculated Measured

First order peak intensity : discrepancy

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Olivier Fruchart - 11/10/2002

  • p.24

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

STM : residual roughness

0.6AL 1.1AL 2AL

STM pictures

  • S. Rousset et al.

Fruchart et al.

Can residual rougness explain

the discrepancy ?

  • S. Padovani et al., Phys. Rev. B 59,

11887 (1999)

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Olivier Fruchart - 11/10/2002

  • p.25

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

STM : simulation of GISAXS from topography

Broad rods Narrow rods

Experim ental procedure ( exam ple : 0 .5 AL)

Raw im age Disk- shaped crystallite Gray level discretization Calculated diffusion

Speckle effect ( ‘beam ’ coherence over the im age)

averaging is necessary

Backs up m odel: reciprocal space is not a sim ple rectangle

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Olivier Fruchart - 11/10/2002

  • p.26

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

STM : simulation of GISAXS from topography Experim ental procedure ( exam ple : 4 AL)

Raw im age Disk- shaped crystallite Gray level discretization

Raw diffusion ‘Background’ substraction

Broad peaks only ( inter- row )

Narrow peaks vanish

  • S. Rousset et al.
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Olivier Fruchart - 11/10/2002

  • p.27

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

STM : simulation of GISAXS from topography Model versus STM

Thickness (AL)

1 2

Model Simulations (STM)

  • O. Fruchart et al.

GPS Padovani et al.

Tip shadow ing effect on calculated GI SAXS

  • overestim ates for low coverage
  • underestim ates for high coverage

Group and tip independant

  • S. Padovani et al., Phys. Rev. B 59,

11887 (1999)

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Olivier Fruchart - 11/10/2002

  • p.28

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

STM : simulation of GISAXS from topography

10 15 20 25 30 35

Thickness (Å)

5

Thickness ( ) Å 2 4

Model

Model

GISAXS STM

Model versus STM: discrepancy rem ains !

Could a periodic stress induced in the Au( 1 1 1 )

substrate by the dots contribute to GI SAXS ?

8AL

GI SAXS intensity rem ains for continuous film s w ith insignificant surface roughness

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Olivier Fruchart - 11/10/2002

  • p.29

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Substrate strain induced by dots stress

Modulation of substrate lateral density. Depth sim ilar to lateral scale

  • V. S. Stepanyuk et al., Phys. Rev. B 62, 15398 (2000)

Elastic theory, atom istic calculations

Example: Negative strain Positive strain Co/ Cu( 001)

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Olivier Fruchart - 11/10/2002

  • p.30

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Xrays : probing substrate periodic strain SXRD: self- organized N/ Cu( 0 0 1 )

0.2AL N/ Cu(001)

S.L. Silva, APL76, 1128 (2000) F.M. Leibsle, SS317, 309 (1994)

Satellites around Cu peak

Periodic surface strain can induce satellite diffraction rods Depth similar to period Small-angle : diffraction satellites around rod (0,0) ?

  • B. Croset, PRL88, 056103 (2002)
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Olivier Fruchart - 11/10/2002

  • p.31

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

GI SAXS from Au(111): is the magnitude so high compared to Co dots ? Effects affecting m agnitude Objection

  • Co: ZCO versus vacuum
  • Au: ZAU(1+ ε) versus ZAU
  • Depth of m odulation t
  • ZAU > ZCO

¯ x 10

  • Shortening of diffraction rods:

Qz ~ 1/ t

¯ x 10

  • Number of atoms ~ t

¯ x 10 ¯ x 10 - 3

Similar orders of magnitude for Co and Au scattering

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Olivier Fruchart - 11/10/2002

  • p.32

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Co/ Au(111): residual strain TEM, plane views EXAFS SXRD

¯ εCo = 3 % @ 2AL ¯ εAu ≥ 0 .1 %

  • H. Ardhuin, J. Cryst. Growth 182, 394 (1997)

¯ εCo = 3- 3.5 % @ 4AL

Marsot et al.

¯ εCo = 2- 3 % @ 2 AL

Marsot et al., Thesis, unpublished.

¯ εCo = 5±1 % @ 2AL

STM dislocation Moirés

  • S. Rousset et al., unpublished ?
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Olivier Fruchart - 11/10/2002

  • p.33

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Why doesn’t the strain release upon percolation?

8AL

I m perfect percolation ?

¯ Au atom s upcom ing from substrate ?

W HY : expanded area attracts Au atoms, not Co atoms (chemical potential) CONSEQUENCE : stabilizes strain modulation (also reduces the total elastic energy)

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Olivier Fruchart - 11/10/2002

  • p.34

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Direct proof of Au up-diffusion ? 1 .1 AL Co/ AU( 1 1 1 )

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Olivier Fruchart - 11/10/2002

  • p.35

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Direct proof of Au up-diffusion ?

tan= 1.3Å/ nm Depth= 1Å tan= 2Å/ nm Depth= 2Å

¯ Au up- diffusion ? ¯ Stacking faults, grain boundaries?

4 AL Co/ AU( 1 1 1 )

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Olivier Fruchart - 11/10/2002

  • p.36

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Au up-diffusion: previous evidences from the litterature

  • M. Speckm ann et al., Phys. Rev. Lett. 75, 2035 (1995)

Annealing

System: Co(5AL)/ Au(111) Experiment: Annealing (240°C, 10-15min) Evidence: Auger, Magnetic anisotropy

Lifting the Au( 1 1 1 ) reconstruction

  • N. Marsot , unpublished

System: Co(< 2AL)/ Au(111) Experiment: Growth Evidence: SXRD

¯ Diffusion channels ? ¯ W here do 4 % Au atom s go ?

( not as 3 rd layer !) Topo Spectro

‘I nterm ixing’

System: Co(≥2AL)/ Au(111) Experiment: Growth Evidence: Au Core-level spectroscopy

¯ Au up- diffusion

  • N. Marsot , Surf.Sci. 377, 225 (1997)
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Olivier Fruchart - 11/10/2002

  • p.37

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Conclusion et perspectives

¯ « Super-diffraction » in-situ sur 0.05MC: études ‘cristallographiques’ ¯ Complémentarité au STM: déformations, percolation, etc. ¯ Rappel: interface peut rester rugueuse même si surface libre se lisse

Conclusions Perspectives

¯ Calculs de relaxation élastique (H. Bulou et al.) ¯ Grand nombre d’ordres de diffraction ¯ Couplage à la diffraction atomique ¯ Etude magnétique ?

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Olivier Fruchart - 11/10/2002

  • p.38

Laboratoire Louis Néel Laboratoire Laboratoire Louis Néel Louis Néel

http:/ / http:/ / lab lab- neel neel.grenoble. .grenoble.cnrs cnrs.fr fr/ them es them es/ couches/ / couches/ ext ext/

Remerciements

  • G. Renaud, M. Noblet, O. Ulrich

DRFMC/SP2M/IRS (CEA), Grenoble

J.-P. Deville, A. Barbier, F. Scheurer, J. Mané-Mané,

  • S. Padovani, I. Chado, J.-P. Bucher,
  • C. Goyhenex, H. Bulou,

IPCMS (CNRS/ULP/ECPM), Strasbourg

  • V. Repain, G. Baudot, S. Rousset

GPS-Jussieu, Paris