1. en interaction avec des plasmas caractérisées par microscopie Raman
Surfaces de Be et de WO3
en interaction avec des plasmas caractérisées par microscopie Raman
Cédric Pardanaud
C. Martin, G. Giacometti, P. Roubin,
H. Hijazi, Y. Addab

2. Plasma wall interaction 
Impurities  (O, N, C, He, Be, W…)
Plasma wall interaction 
Safety issue (T retention, dusts production)
Material modifications (Mixed materials)
Context
Erosion/deposition
T up to ≈1000°C
ITER/JET
(Be/W)
1/7

3. Plasma wall interaction 
Impurities  (O, N, C, He, Be, W…)
Plasma wall interaction 
Safety issue (T retention, dusts production)
Material modifications (Mixed materials)
Main aim:
Ability to detect by chemical bondings:
- hydrogen isotope in materials
- mixed materials
Context
Erosion/deposition
T up to ≈1000°C
ITER/JET
(Be/W)
1/7

4. Experimental tool: Raman microscopy
(lL=514.5nm)
LASER
focalised by
a microscope
Inelastic scattering
Solid vibrational modes E1 E2
Bending
Stretching, …
Intensity (cnt.)
Raman shift (cm-1)
Sensitive to chemical bonds (Be-D, Be-H, Be-Be, W-O, C-C,…)
Environmental effects (structure, defects, stress,…)
Local probe (surface ≈ 1mm2, depth ≈ 30 nm)
« Fast » technique (1 spectrum in ≈ 1 s to few hours)
2/7

5. JET sample measurements:
Observations in tokamaks: JET mirror samples
JET sample measurements:
- KTH, Stockholm
Few nm deposits with:
Be, C, O,… Mo
3/7

6. JET sample measurements:
Observations in tokamaks: JET mirror samples
JET sample measurements:
- KTH, Stockholm
Few nm deposits with:
Be, C, O,… Mo
MoO3-x
 Mirror (Mo) oxydation
 Trace of C-O (but no aromatic carbon phases)
 Be carbide phases ?
 D related bonds ?
3/7

7. JET sample measurements:
Observations in tokamaks: JET mirror samples
JET sample measurements:
- KTH, Stockholm
C-O
Few nm deposits with:
Be, C, O,…
C=O Mo
MoO3-x
 Mirror (Mo) oxydation
 Trace of C-O (but no aromatic carbon phases)
 Be carbide phases ?
 D related bonds ?
3/7

8. JET sample measurements:
Observations in tokamaks: JET mirror samples
JET sample measurements:
- KTH, Stockholm
C-O
Few nm deposits with:
Be, C, O,…
C=O Mo
Be-C ???
MoO3-x
 Mirror (Mo) oxydation
 Trace of C-O (but no aromatic carbon phases)
 Be carbide phases ? → H retention modification !
 D related bonds ?
3/7

9. Simulation in lab’: Deuterium implantation in Beryllium
Lab’ experiments:
- FZJ, Julich
2 keV D+
Normal incidence
F up to D+.cm-2 Be
4/7

10. Dendrites are made of BeD2 cristal Reservoir of D !
Simulation in lab’: Deuterium implantation in Beryllium
Lab’ experiments:
- FZJ, Julich
2 keV D+
Normal incidence
F up to D+.cm-2 Be
Dendrites are made of BeD2 cristal Reservoir of D !
4/7

11. Simulation in lab’: Beryllium carbide identification
Lab’ experiments:
INOE, Bucharest
TVA deposition method
Quantum calc.:
IRSN+PIIM
(see L. Ferry’s talk)
Codeposits :
Be + C
Wafer
 Comparison with quantum modelling (DFT)
Be2C phase formation
 Coexistence of Be+Be2C+C phases
5/7

12. Simulation in lab’: Beryllium carbide identification
Lab’ experiments:
INOE, Bucharest
TVA deposition method
Codeposits :
Be + C
Wafer
 Comparison with quantum modelling (DFT)
Be2C phase formation
 Coexistence of Be+Be2C+C phases
5/7

13. Tungsten oxide formation and retention modification
Lab’ experiments:
PIIM, Marseille
Thermal growth
Heated under vacuum W
Heating
WO3 W
Different kind of oxides: need to better characterize them !
D-retention in each of these oxides ?
6/7

14. Tungsten oxide formation and retention modification
Lab’ experiments:
PIIM, Marseille
Thermal growth
Heated under vacuum W
Heating
WO3
750°C W
5 mm
Different kind of oxides: need to better characterize them !
D-retention in each of these oxides ?
6/7

15. Tungsten oxide formation and retention modification
Lab’ experiments:
PIIM, Marseille
Thermal growth
Heated under vacuum
And/or exposed to plasmas/ions W
Heating
WO3 W
Irradiation W
5 mm
Different kind of oxides: need to better characterize them !
D-retention in each of these oxides ?
6/7

16. Conclusion: prepare post-mortem analyses in tokamaks
Spectroscopic parameters (line width and position)
7/7

17. Conclusion: prepare post-mortem analyses in tokamaks
Spectroscopic parameters (line width and position)
7/7

18. Conclusion: prepare post-mortem analyses in tokamaks
7/7

19. Conclusion: prepare post-mortem analyses in tokamaks
7/7

20. Quantitative can be possible by comparing with Lab experiments
Conclusion: prepare post-mortem analyses in tokamaks
NTR deposits contain less D than TPL deposits
Able to make statistics on large scale
Quantitative can be possible by comparing with Lab experiments
7/7

21. Collaborators M. I. Rusu, C. Pardanaud,
C. Martin, Y. Addab, H. Hussein, P. Roubin, M. Minissale,
L. Ferry, F. Virot, M. Barrachin , Y. Ferro,
C Porosnicu, P Dinca, M Lungu, C P Lungu,
M. Köppen, T. Dittmar, P. Dollase, M. Oberkofler, Ch. Linsmeier
AMU, Marseille, France
IRSN, Cadarache, France
INOE 2000, Bucharest, Romania
INFLPR, Bucharest, Romania
IPP, Garching, Germany
IEK4, Jülich, Germany