Transcript Diapositive 1

Energy deposition
Radiation-induced
material modifications
Lattice

Electrons

nuclear, elastic
energy deposition
Ionising
energy deposition
Small
linear regime
Strong
non -linear regime
Frenkel-pair creation
linear cascades
Classical radiolysis
Non-linear cascades
High LET effects
Tracks regime
Synergy?
The displacement spectrum
T
1
d σ (E1 ,T)
W(T) =
N
T
dT


D

σ D (E1 ) Td
dT
T1/2
 N  T  d σ (E ,T)
D
1 =
2
Abromeit C. JNM 216 (1994) 78
!
1
Td
σ D (E1 )
Nuclear reactions
Nuclear reactions
elastic
V. M Agramovich and V; V; Kirsanov
Physics of rad effects in crystals R. A. Johnson and A; N Orlov Eds. N-H 1986
The cascades: the mean free path
T>
150
5 keV
100
50
50 keV
0
TRIM
-50
0
50
100
150
200
250
(Å)
Averback R. S. JNM 216 (1994) 49
Cascades sub-cascades
Linear-non linear
150
5 keV
Linear
All the atoms in movement
collide with atoms at rest
dpa makes sense
100
50
50 keV
0
-50
0
50
100
150
Sub-cascades
One dense cascade
200
250
Non-linear
Atoms in movement collide together
collective motion of atoms
local melting
shock-wave generation
Recombinations:
one dpa is not a defect
Low T, low T1/2
z = “resistivity” defect/ “Kinchin and Pease”dpa
0.004
0.003
concentration
dc
=σ D linear regime:1 dpa = 1 defect
dΦ
dc
=σ D (1-V0 c)2
dΦ
dc
=(σ D (1-V0 c) 2 -σ r c)
σr  10 σD
dΦ
Exemple : Cu
sd 140 barns
n0 135 volumes atomiques
sr 4000 barns
0.002
0.001
0.000
0
5E+19
1E+20
fluence
High T
Low T, high T1/2
Radiation-enhanced
diffusion
Transient and stationary
regimes
Influence of:
permanent sinks
flux
T1/2 Td
Averback R. S. JNM 216 (1994) 49
Recombinations:
cascades
NiAl
Au
0.1 ps
0.62 ps
5 ps
17.7 ps
Averback R. S. JNM 216 (1994) 49
0.3 ps
3.2 ps
0.5 ps
1 ps
2 ps
6 ps
11.5 ps
23 ps
PKA 10 keV
Inelastic damage
What happens to the projectile
Stopping power
range
stragglings
What happens to the solid
What happens to: the projectile
: secondary particles:
electrons
recoils
Projectile ion : the atomic processes
proton on hydrogen
proton on aluminium
V p  Ve
Projectile ion: the electronic stopping; high velocity
Bethe
1


Corrections :
•
•
•
•
Relativistic
Density
Deep levels
Effective charge
I=9,2 Z
800
mean ionization potential [eV]
4 Z12e4  2mev12 
dE

 NZ2
ln 
2
dx e
I 
mev

Rn
600
400
Xe
Kr
200
Ar
0
0
20
40
2 e4  

2
4 Zeff
 1  C
  2mev1 

dE
2  ln 


 NZ2
ln






 1  2  Z2
dx e
mev2   I 

1






60
80
100
Z2
Projectile ion: the electronic stopping
pouvoir d'arrêt nucléaire
dE/dx
(MeV / cm )
pouvoir d'arrêt élec tronique
The Bragg peak
10
U
5
Kr
10
10
10
4
Ar
3
U
2
H
10
1
H
0,001
0,01
Ar
0,1
1
énergie (MeV / uma)
1000
C 12.5 MeV/A
600
e
(dE/dx) (keV/µm)
800
400
200
0
0
100
200
300
400 500 600
Parcours (µm)
700
10
Kr
100
Projectile: Swift heavy ions
Secondary particles: electrons
Velocity effect
Projectile: photons electrons
Secondary particles: electrons
Compton
photons  60Co
photoelectric
photons X 250 keV
électrons 3H 5,5 keV
The (dE/dx)e distributions
Bragg peak
of electrons
Fraction of the dose
(dE/dx)e of the
projectile over a
given thickness
(dE/dx)e of the
secondary electrons
(dE/dx)e (keV/µm)
Projectile: low energy heavy ions
Secondary particles: recoils
The recoils
makes
the inelastic
energy deposition
Xe 100keV
Projectile: (100 to 50) keV (dE/dx)n ≈ 2.5 (dE/dx)e
Radiolysis Low LET
Radiolysis is the creation of permanent defects
due to the non-radiative recombination
of an elementary excitation (a hole-electron pair)
The radiolysis yield G
G=
Quantum yield
N (mol)
E i (J)
N
η=
N e-h
in a linear regime: G =
N
 Ei 3 E g 
Ne-h
c (mol/kg)
D(J/kg)
Ei This is the “Kinchin and Pease”
for inelastic damage
3 Eg
The radiolysis yield G
Typical, yields (could be zero)
Organic: a few 10-7 mol/J
100 eV
alkali halides (10-8 to 10-9) mol/J
1 – 10 keV
The yield concept is never use for elastic damage
If one dpa = one defect (z=1)
G=
NA σD
 dE dx  n
For ions (7 10-8 to 1.5 10-7) mol/J
The low LET radiolysis conditions
The available energy, Egap (in fact Ex < Egap)
> the formation energy of the Frenkel pair.
the radiolysis can only occurs in insulators or wide band-gap semiconductors.
The excitation must be localised on one atomic (or molecular) site
Non-radiative transitions, allowing an efficient kinetic energy transfer to an atom,
must prevail over radiative transitions
Could work in
alkali halides
(anions and cations)
alkaline-earth halides
Difficult in
oxides
Frenkel cation
Frenkel anion
Ex
Egap
Low LET radiolysis versus ballistic damage
1) Radiolysis is not universal, not easily predictable
2) Is in essence temperature dependent
3) Spans over a wide time scale
4) Occurs generally on one sub-lattice (anions)
5) Radiolysis occurs occasionally
when it occurs, it is with a good energetic efficiency.
Elastic damage occurs every time
but with a relatively poor energetic efficiency.
Charge-carriers self-trapping
Self trapping of charge carriers results from
a competition between deformation and polarisation of the lattice
STE:
Se et chalcogenides
STE:
BeO-YAG
MgO, Al2O3
STE
Self trapped holes
AgCl
KCl
AgCl
KCl
CaF2
CaF2
c-SiO2
STE Luminescence
STE have several luminescence states
a strong Stokes shift
very variable lifetime: ns to ms
STE-defect conversion
Correlation - anticorrelation
STE luminescence and defect creation
Correlation conversion thermal
STE triplet -> F +H
small S/D
Temporal dynamics
Elastic damage : 25 keV Cu cascade over at 10 ps
only numerical simulations
Radiolysis: fast processes (ps) charge-carrier trapping
conversion from STE highly excited stated
slow processes (µs to ms) from STE triplet states
Also measurements!!
metastable defects
Conversion STE-defects
a-SiO2
Transient defects
c-SiO2
Also in SrTiO3, MgO, Al2O3
Resistant and sensitive materials
Resistant:
Metals, semi-conductors.
crystalline Oxides. c-SiO2 (flux) NaAlSi3O8 :
metastables (SrTiO3, MgO, Al2O3, c-SiO2)
Sensitive:
Alkali halides
Alkaline-earth halides CaF2, MgF2, SrF2 : Gmeta , Gstable very low
KMgF3, BaF1.1B 0.9, AlF3 (flux?), LiYF4: may be
Silver halides AgCl; AgBr
Amorphous solids a-SiO2 , a-As2Se3, a-As2S3, a-Se, a-As
Water and organic mater (bio matter)
Energy deposition
Radiation-induced
material modifications
Lattice

Electrons

nuclear, elastic
energy deposition
Ionising
energy deposition
Small
linear regime
Strong
non -linear regime
Frenkel-pair creation
linear cascades
Classical radiolysis
Non-linear cascades
High LET effects
Tracks regime
Synergy?
“Classical” track formation in insulators
MICA
YIG
LET threshold
Amorphisation
fluctuations
critical size
induced stress
S. Bouffard et al. Phil. Mag. A 81 (2001) 2841
M. Toulemonde, F. Studer Phil. Mag. A 58 (1988) 799
Etching of
the amorphous core
GSI image
Nanotechonology (ITT)
M. Toulemonde et al. J. Appl Phys. 68 (1990) 1545
Less common High LET effects
Vierge
450
400
(11-1)M
4.0E+12
1.0E+13
(111)M
350
Nbe de coups
1.0E+12
ZrO2
1.2E+13
1.6E+13
300
2.4E+13
250
(101)Q
200
150
100
50
0
1600
1650
1700
1750
1800
1850
1900
1950
Canaux
Crystal to crystal transformations can exist
monoclinic-> tetragonal
Two process (incubation fluence)
Unexpected High LET effects
Some metals are sensitive to high LET radiation
High Tc superconductors are sensitive to high LET radiation
(pinning of vortices)
Unexpected High LET effects
Plastic instability of amorphous materials: the hammering effect
1.7
1013
Co75Si15B10
Xe/cm2; 2.8 MeV/A; 50K
Klaumünzer et al. Mat. Res. Proc. 93 (1987) 21
Ion-aligned nanoparticle elongation
sample implanted at 1 · 1017 Co/cm2 at 873 K and irradiated
at (a) 1013, (b) 3 · 1013, (c) 6 · 1013 and (d) 1014 I/cm2.
D'Orleans-C; Stouter-JP; Estournes-C; Grab-JJ; Muller-D;
Guille-JL; Richard-Plouet-M; Cerruti-C; Haas-F
NIM B 216: 372-8 2004
PHYSICAL REVIEW B 67, 220101 (2003)
Fragmentation and grain rotation in NiO single crystals (Klaumuenzer REI-2007)
Polygonisation (UO2, CaF2)
Bibliography
Cargèse
Summer schools
The French summer school
“Materials Under Irradiation”, Giens 1991,
Trans Tech Publications, 1992 (in English)
The USA summer school
“Fundamentals of Radiation Damage”, Urbana in 1993,
J. Nucl. Mat., volume 216 (1994)
The French summer schools
Lalonde les Maures 1999 et 2000, 2007 (PAMIR)
Not published, but printed material (in French)
Bibliography
Classics
Chr. Lehmann,
Interaction of Radiation with Solids
and Elementary Defect Production,
Series on Defects in Crystalline solids,
vol. 10. North-Holland, 1977
N. Nastasi, J. W. Mayer and J. K. Hirvonen,
Ion-Solid Interaction, Fundamentals and Applications
Cambridge Solid State Science Series, 1996
R. A. Johnson and A. N. Orlov Eds
Physics of Radiation Effects in Crystals,
North-Holland, 1986
Specific to radiolysis
N. Itoh and A. M. Stoneham
Material Modification by Electronic Excitation,
Cambridge University Press, 2001
Projectile: electron capture Very very slow HCI
H. Kurtz et al, Phys. Rev. A49 (1994) 4693
proton on
hydrogen
V p  Ve
Bibliography
Never go to the beach without a good book
More specific to radiolysis
N. Itoh and A. M. Stoneham
Material Modification by Electronic Excitation,
Cambridge University Press, 2001
F. Agullo-Lopez, C. R. A. Catlow, P. D. Townsend
Point defects in materials
Academic Press 1988
N. Itoh ed
Defects Processes induced by electronic excitation in insulators
World Scientific 1989
K. S. Song, R. T. Williams
Self-trapped excitons
Springer-Verlag 1993
P. D. Townsend, P. J. Chandler, L. Zhang
Optical effects of ion implantation
Cambridge 1994
0.004
Low T, low T1/2
dc
=σ D linear regime:1 dpa = 1 defect
dΦ
dc
=σ D (1-V0 c)2
dΦ
dc
=(σ D (1-V0 c) 2 -σ r c)
dΦ
concentration
0.003
0.002
Exemple : Cu
sd 140 barns
n0 135 volumes atomiques
sr 4000 barns
0.001
0.000
0
5E+19
1E+20
fluence
8
c  s d
c  (s d (1  V0c )2  s r c )
   F c
   F (s d (1  V0c )2  s r c )
d
 2
  F s d (1  V0
)  s r 
d
F
F ~ 1 µ.cm / % defect
6
d/ d  .cm3/e-)
c  s d (1  V0c )2 
7
5
4
3
2
1
0
0
2
4
6
8
  .cm)
J. Dural et al, J. de Physique 38
(1977) 1007
The (dE/dx)e distributions
Bragg peak
of electrons
Fraction of the dose
(dE/dx)e of the
projectile over a
given thickness
(dE/dx)e of the
secondary electrons
(dE/dx)e (keV/µm)
Low LET radiolysis: organics; water
The primary species

aq.
e

2
*
2
; HO ; HO
Fragmentation of H2O+
Hole migration
dissociation
H3O+
OH
0.3 nm
Fragmentation of H2O*
0.8 nm
O (3P)
H
Up to 60 reactions
Distances empirically
< 10-12 s
10-12 s < blobs and short tracks < 10-7 s
in bulk >10-7 s
Low LET radiolysis: only role of heterogeneity
Rendement d'électrons solvatés
6
G molecules/100 eV
5
4
H 30 MeV/u
3
2
C 30 MeV/u
Kr 65 MeV/u
1
0
-12
10
-11
10
10
-10
-9
10
t (s)
10
-8
10
-7
10
-6
Low LET radiolysis: specific role; multi-ionisation
Double ionisation and superoxide OOH°
Ar
C
H
Gervais-B; Beuve-M; Oliver-GH; Galassi-ME
Radiation-Physics-and-Chemistry.
2006; 75(4): 493-513
Projectile: photons electrons
Secondary particles: electrons
100
énergie photons
Fraction
80
60
Co
lobes (E<100 eV)
60
40
traces courtes
20
lobes 100eV<E<500 eV
0
10
spurs
E<100 eV
blobs
E de 100 à 500 eV
3
Primary electron
Short track
E< 5000 eV
4
5
6
10
10
10
énergie initiale de l'électron (en eV)
Annex track
E> 5000 eV
10
7
Luminescence quenching
1
 1   R1   NR
(T )