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Energy deposition
ElectronsLattice
Per
turb
a tio
n
Strongnon -linear regime
Smalllinear regime Frenkel-pair creation
linear cascades
Non-linear cascades
Classical radiolysis
Radiation-induced material modifications
nuclear, elasticenergy deposition Ionising
energy deposition
Synergy?
High LET effectsTracks regime
The displacement spectrum
1/2
d
D
1
T
1
T
D
N T d σ (E ,T)1 =2 σ (E )
d
T1
DD 1 T
1 d σ (E ,T)W(T) = N T dT
σ (E ) dT
! Nuclear reactions
Nuclear reactions
elastic
Abromeit C. JNM 216 (1994) 78
V. M Agramovich and V; V; KirsanovPhysics of rad effects in crystals R. A. Johnson and A; N Orlov Eds. N-H 1986
The cascades: the mean free path
T >
-50
0
50
100
150
0 50 100 150 200 250
50 keV
5 keV
TRIM
(Å)
Averback R. S. JNM 216 (1994) 49
Linear-non linearCascades sub-cascades
-50
0
50
100
150
0 50 100 150 200 250
50 keV
5 keV
One dense cascade
Sub-cascades
LinearAll the atoms in movementcollide with atoms at rest
dpa makes sense
Non-linearAtoms in movement collide together
collective motion of atoms local melting
shock-wave generation
Recombinations:one dpa is not a defect
D
2D 0
2D 0 r
dc=σ
dΦdc
=σ (1-V c)d
linea
Φdc
=(σ (1-V c) -σ c)d
r regime:1 dpa = 1 de e
Φ
f ct
Low T, low T1/2
r Dσ 10 σ
Low T, high T1/2
1/2 dT T
=
“re
sist
ivit
y” d
efec
t/ “
Kin
chin
and
Pea
se”d
pa
High T
Radiation-enhanced diffusion
Transient and stationaryregimes
Influence of: permanent sinks
flux
Averback R. S. JNM 216 (1994) 49
0.000
0.001
0.002
0.003
0.004
0 5E+19 1E+20fluence
con
cen
trat
ion
Exemple : Cud 140 barnsn0 135 volumes atomiquesr 4000 barns
Recombinations:cascades
0.1 ps 0.3 ps
0.5 ps
2 ps
1 ps
6 ps
Au
NiAl
PKA 10 keV
0.62 ps 3.2 ps
5 ps
17.7 ps
11.5 ps
23 ps
Averback R. S. JNM 216 (1994) 49
Inelastic damage
What happens to the projectile
What happens to the solid
Stopping powerrangestragglings
What happens to: the projectile : secondary particles: electrons
recoils
Projectile ion : the atomic processes
proton on hydrogen
p eV V
proton on aluminium
2 4 21 1
2 21
4 2ln e
ee
Z e m vdE NZdx Im v
Bethe
0
200
400
600
800
0 20 40 60 80 100
mea
n io
niza
tion
pot
enti
al [
eV]
Z2
Ar
Kr
Xe
Rn
I=9,2 Z
Corrections :• Relativistic• Density• Deep levels• Effective charge
4 21 2
22 21
2
21ln
1
4 2lneff e
ee
e m vd CZ
E NZdx m v
Z
I
Projectile ion: the electronic stopping; high velocity
U
U
K r
K r
A r
A r
HH
p o uvo ir d 'a rrê t nuc lé a ire
p o uvo ir d 'a rrê t é le c tro niq ue
1001010 ,10 ,001 0 ,01
é ne rg ie (M e V / um a )
101
105
d E/d x(M e V / c m )
104
103
102
The Bragg peakThe Bragg peak
Projectile ion: the electronic stopping
0
200
400
600
800
1000
0 100 200 300 400 500 600 700
(dE
/dx)
e (keV
/µm
)
Parcours (µm)
C 12.5 MeV/A
Velocity effect
Projectile: Swift heavy ionsSecondary particles: electrons
photons 60Co photons X 250 keV électrons 3H 5,5 keV
Projectile: photons electronsSecondary particles: electrons
Compton photoelectric
The (dE/dx)e distributions
Fra
ctio
n of
the
dose
(dE/dx)e (keV/µm)
Bragg peakof electrons
(dE/dx)e of theprojectile over a given thickness
(dE/dx)e of thesecondary electrons
The recoilsmakes
the inelastic energy deposition
Xe 100keV
Projectile: (100 to 50) keV (dE/dx)n ≈ 2.5 (dE/dx)e
Projectile: low energy heavy ionsSecondary particles: recoils
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
c (mol/kg)in a linear regime: G =
D(J/kg)
e-h i g
N Nη =
N E 3 EQuantum yield
i
N (mol)G =
E (J)
This is the “Kinchin and Pease” for inelastic damage
ie-h
g
EN
3 E
The radiolysis yield G
Organic: a few 10-7 mol/J alkali halides (10-8 to 10-9) mol/J
Typical, yields (could be zero)
The yield concept is never use for elastic damageIf one dpa = one defect (=1)
A D
n
N σG =
dE dxFor ions (7 10-8 to 1.5 10-7) mol/J
100 eV 1 – 10 keV
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
The low LET radiolysis conditions
Frenkel cation Frenkel anion Ex
Egap
Could work inalkali halides(anions and cations)alkaline-earth halides
Difficult in oxides
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.
Low LET radiolysis versus ballistic damage
Charge-carriers self-trapping
STE:Se et chalcogenides
STE:BeO-YAGMgO, Al2O3
Self trapping of charge carriers results from a competition between deformation and polarisation of the lattice
Self trapped holes AgCl
CaF2
KCl
KCl
AgCl
CaF2
c-SiO2
STE
STE Luminescence
STE have several luminescence statesa strong Stokes shift very variable lifetime: ns to ms
STE-defect conversion
Correlation - anticorrelationSTE luminescence and defect creation
Correlation conversion thermalSTE triplet -> F +Hsmall S/D
Temporal dynamics
Elastic damage : 25 keV Cu cascade over at 10 psonly numerical simulations
Radiolysis: fast processes (ps) charge-carrier trappingconversion from STE highly excited stated
slow processes (µs to ms) from STE triplet statesAlso measurements!!metastable defects
Conversion STE-defects
c-SiO2
a-SiO2
Also in SrTiO3, MgO, Al2O3
Transient defects
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 lowKMgF3, BaF1.1B 0.9, AlF3 (flux?), LiYF4: may be
Silver halides AgCl; AgBrAmorphous solids a-SiO2 , a-As2Se3, a-As2S3, a-Se, a-As
Water and organic mater (bio matter)
Energy deposition
ElectronsLattice
Per
turb
a tio
n
Strongnon -linear regime
Smalllinear regime Frenkel-pair creation
linear cascades
Non-linear cascades
Classical radiolysis
Radiation-induced material modifications
nuclear, elasticenergy deposition Ionising
energy deposition
Synergy?
High LET effectsTracks regime
MICAYIG
LET threshold
Amorphisation
Etching of the amorphous core
M. Toulemonde et al. J. Appl Phys. 68 (1990) 1545
GSI image
S. Bouffard et al. Phil. Mag. A 81 (2001) 2841fluctuationscritical size
induced stress
M. Toulemonde, F. Studer Phil. Mag. A 58 (1988) 799
“Classical” track formation in insulators
Nanotechonology (ITT)
0
50
100
150
200
250
300
350
400
450
1600 1650 1700 1750 1800 1850 1900 1950
Canaux
Nbe
de
coup
s
Vierge
1.0E+12
4.0E+12
1.0E+13
1.2E+13
1.6E+13
2.4E+13
(11-1)M(111)M
(101)Q
ZrO2
Crystal to crystal transformations can existmonoclinic-> tetragonalTwo process (incubation fluence)
Less common High LET effects
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
Klaumünzer et al. Mat. Res. Proc. 93 (1987) 21
Co75Si15B10
1.7 1013 Xe/cm2; 2.8 MeV/A; 50K
Plastic instability of amorphous materials: the hammering effect
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-FNIM B 216: 372-8 2004
PHYSICAL REVIEW B 67, 220101 (2003)
Ion-aligned nanoparticle elongation
Fragmentation and grain rotation in NiO single crystals (Klaumuenzer REI-2007)
Polygonisation (UO2, CaF2)
Bibliography
CargèseSummer schoolsThe 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
ClassicsChr. Lehmann, Interaction of Radiation with Solidsand 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 EdsPhysics of Radiation Effects in Crystals,North-Holland, 1986
Specific to radiolysis
N. Itoh and A. M. StonehamMaterial Modification by Electronic Excitation,Cambridge University Press, 2001
H. Kurtz et al, Phys. Rev. A49 (1994) 4693
Projectile: electron capture Very very slow HCI
proton on hydrogen
p eV V
Bibliography
Never go to the beach without a good book
More specific to radiolysis
N. Itoh and A. M. StonehamMaterial Modification by Electronic Excitation,Cambridge University Press, 2001
F. Agullo-Lopez, C. R. A. Catlow, P. D. TownsendPoint defects in materialsAcademic Press 1988
N. Itoh edDefects Processes induced by electronic excitation in insulatorsWorld Scientific 1989
K. S. Song, R. T. WilliamsSelf-trapped excitonsSpringer-Verlag 1993
P. D. Townsend, P. J. Chandler, L. ZhangOptical effects of ion implantation Cambridge 1994
D
2D 0
2D 0 r
dc=σ
dΦdc
=σ (1-V c)d
linea
Φdc
=(σ (1-V c) -σ c)d
r regime:1 dpa = 1 de e
Φ
f ct
Low T, low T1/2
0.000
0.001
0.002
0.003
0.004
0 5E+19 1E+20fluence
con
cen
tra
tion
Exemple : Cud 140 barnsn0 135 volumes atomiquesr 4000 barns
20
20
20
20
(1 )
( (1 ) )
( (1 ) )
(1 )
d
d
d r
F
F d r
F d rF
c
c V c
c V c c
c
V c c
dV
d
0
1
2
3
4
5
6
7
8
0 2 4 6 8 .cm)
d/ d
.cm
3/e
-)
F ~ 1 µ.cm / % defect
J. Dural et al, J. de Physique 38 (1977) 1007
The (dE/dx)e distributions
Fra
ctio
n of
the
dose
(dE/dx)e (keV/µm)
Bragg peakof electrons
(dE/dx)e of theprojectile over a given thickness
(dE/dx)e of thesecondary electrons
Fragmentation of H2O*
Fragmentation of H2O+
Hole migration
H3O+
OH
0.3 nm
dissociationHole migrationHole migration
H3O+
OH
0.3 nm
dissociation
H3O+
OH
0.3 nm
dissociation
0.8 nm
HO (3P)
0.8 nm
HO (3P)
0.8 nm
HO (3P)
The primary species
Distances empirically
*. 2 2; ;aqe HO HO
Low LET radiolysis: organics; water
Up to 60 reactions
< 10-12 s10-12 s < blobs and short tracks < 10-7 s
in bulk >10-7 s
0
1
2
3
4
5
6
10-12 10-11 10-10 10-9 10-8 10-7 10-6
G m
olec
ules
/100
eV
t (s)
H 30 MeV/u
C 30 MeV/u
Kr 65 MeV/u
Rendement d'électrons solvatés
Low LET radiolysis: only role of heterogeneity
Double ionisation and superoxide OOH°
H
ArC
Gervais-B; Beuve-M; Oliver-GH; Galassi-MERadiation-Physics-and-Chemistry. 2006; 75(4): 493-513
Low LET radiolysis: specific role; multi-ionisation
0
20
40
60
80
100
103 104 105 106 107
Fra
ctio
n
énergie initiale de l'électron (en eV)
lobes (E<100 eV)
traces courtes
lobes 100eV<E<500 eV
énergie photons 60Co
Projectile: photons electronsSecondary particles: electrons
E<100 eV
E> 5000 eVShort track
Primary electron
E< 5000 eV
Annex track
blobsE de 100 à 500 eV
spurs
Luminescence quenching
)(111 TNRR