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Evaluation of different sensor materials for the medipix X-ray detectors [Elektronische Ressource] / Michaela Mitschke

115 pages
DoktorgradesEvaluationUnivofhkDierentergSensoonrMaterialsErlangen-N?rnfoErlangungrorgelegtthehaelaMedipixausX-Rah-Alexanderyersit?tbrszurDendesvvhenFakult?tenederErlangenFProf.AlsericDissertationterstatter:genehmigtorsitzendervH?deronAndenDr.PromotionskD.-PhenericFDr.akult?tenZwderterstatter:UnivSmithersit?tderErlangen-N?rnommission:bDr.erg.TErstbaghderProf.mG.?ndlictonheneitbPr?fung:h3.Prof.MaiK.2006VCrystallographicContents.1.IntroA81.2..X-Ra.yyofrs.3.2.1.In..of.X-RaSensorysShoandCollectionElectrons.with.Matter5.3.........r.of.......Crystals...7.2...rt.103.3.2.2.SignalExpGeneration.in..X-RaChargey...............GaAs.6.1.y.....Homogeneit..10.3.The.Medipixandofrs.15.3.1.GeneralProp.erties..Conclusions.afer.Synchrotron.109.37.and.........37.tal.Sharing...........ulation...............5.4............15.3.2.T.ec66hnologyrs.Medipix1.trate.e.Thic.Sensors.......6.2.................73.of.Senso.7.1.GaAs.............ation.the.y.......ry.A.to19994GuideInitial101DistributionundofLaChaerrge5.1CaChargerriersChargeinthe.Senso.r.La.y.er.23.4.1.
Voir plus Voir moins

Doktorgrades
Evaluation
Univ
of
hk
Dierent
erg
Senso
on
r

Materials
Erlangen-N?rn
fo
Erlangung
r
orgelegt
the
haela
Medipix
aus
X-Ra
h-Alexander
y
ersit?t

b
rs
zur
Den
des

v

v
hen

F

akult?ten
e
der
Erlangen
FProf.
Als
eric
Dissertation
terstatter:
genehmigt
orsitzender
v
H?der
on
An
den
Dr.

Promotionsk

D.-P
hen
eric
F
Dr.
akult?ten
Zw
der
terstatter:
Univ
Smith
ersit?t
der
Erlangen-N?rn
ommission:
b
Dr.
erg
.
T
Erstb
ag
h
der
Prof.
m
G.
?ndlic
ton
hen
eitb
Pr?fung:
h
3.
Prof.
Mai
K.
2006
VCrystallographic
Contents
.
1
.
Intro
A

8
1
.
2
.

.
X-Ra
.
y
y

of
rs
.
3
.
2.1
.
In
.

.
of
.
X-Ra
Sensor
ys
Sho
and
Collection
Electrons
.
with
.
Matter
5.3
.
.
.
.
.
.
.
.
.
r
.
of
.
.
.
.
.
.
.
Crystals
.
.
.
7.2
.
.
.
rt
.
103
.

3
.
2.2
.
Signal
Exp
Generation
.
in
.

.
X-Ra
Charge
y
.

.
.
.
.
.
.
.
.
.
.
.
.
.
.
GaAs
.
6.1
.
y
.
.
.
.
.
Homogeneit
.
.
10
.
3
.
The
.
Medipix
and

of
rs
.
15
.
3.1
.
General

Prop
.
erties
.
.
Conclusions
.
afer
.
Synchrotron
.
109
.
37
.
and
.
.
.
.
.
.
.
.
.
37
.
tal
.
Sharing
.
.
.
.
.
.
.
.
.
.
.
ulation
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
5.4
.
.
.
.
.
.
.
.
.
.
.
.
15
.
3.2
.
T
.
ec
66
hnology
rs
.
Medipix1
.
trate
.
e
.
Thic
.
Sensors
.
.
.
.
.
.
.
6.2
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
73
.
of
.
Senso
.
7.1
.
GaAs
.
.
.
.
.
.
.
.
.
.
.
.
.
ation
.
the
.
y
.
.
.
.
.
.
.
ry
.
A
.
to
19
99
4
Guide
Initial
101
Distribution
und
of
La
Cha
er
rge
5.1
Ca
Charge
rriers
Charge
in

the
.
Senso
.
r
.
La
.
y
.
er
.
23
.
4.1
.
The
5.2
Mon
erimen
te

Carlo
Charge
Sim
.
ulation
.
T
.
o
.
ol
.
R
.
OSI
.
.
.
.
.
.
.
.
46
.
Sim
.
of
.
Sharing
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
59
23
Summary
4.2
.
Range
.
and
.
P
.
ath
.
of
.
Photo-Electrons
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
6
.
Senso
.
fo
.
the
.
69
.
Coun
.
and
.

.
La
.
er
.
kness
.
the
24
.
4.3
.
Loss
.
of
.
Spatial
.
Resolution
.
due
.
to
70
Multiple
Sensor

y
Electrons
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
26
.
4.4
.
Summary
.
.
.
.
.
.
.
.
.
.
7
.
Investigations
.

.
GaAs
.
r
.
77
.
Characterisation
.
the
.
Sensors
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
77
.
Observ
.
of
.
inside
.

.
La
.
er
.
.
.
.
.
.
.
.
.
.
.
90
.
Summa
35
and
5
95
T
Sho
ransp
Guide
o
W
rt
Probing
of
B
Cha
rt
rge
to
Ca
Measurements
rriers
Bibliography
in
Zusammenfassung
the

Senso
iii
rivZ
the
Intro
in

v
Dieren
of
t
ersion
X-ra
A
y
threshold.
imaging
with
systems

ha
Medipix
v

e

emerged
and
since
for
the
required
disco
and
v
b
ery
ws
of
A
this
w
radiation
with
in
of
1895
as
b
of
y
harge
W.C.
the
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a
tgen
is

insucien
Photographic
y
lms
e
ha
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v

e
of
b

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tions
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an

only

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ts
ectral
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lik
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e
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applications

sciences.

e.g.
ha
uation
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bump
e

b
ere
een
they
used
a
since
electron
the
[13]
early
h
1960s.
and
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ers
driving
ha
elds
a
for
with
the

dev
[15]
elopmen
b
t
t
of
astronomical
fast
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wn
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single
sciences,

esp
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ecially


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y

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ternal
e
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test-
ted
ing.

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than

prev
h

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is
from

the
sensor
spin-o
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of
the

(at
dev
knesses)
elop
at
ed
energies
for
man
high

energy
and
particle
ound
ph
lik
ysics,
or
b
higher
eing

optimized
ere
for
onded
radiation
and
hardness,

small

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olumes,
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readout
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ariet
lo
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for
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tenance.
neutron
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design

exibilit
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of
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la


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y
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e
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w
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CERN
and
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ere
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w
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ork
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of
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the

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ora-
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tion
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a
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sync

applications.
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pixel
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pixel
designed

the
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[8
are
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photon
osed
ounting
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hnique
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the
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o
a
separate
ter
parts:

a
pixel
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the
la

y
is
er
to
and
in
a
threshold
readout
the

is
hip.

Photons
if
are

absorb
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ed
larger
in
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a
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high
en
resistivit
the
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er
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er,
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t
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material

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ha
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e

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h
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dio
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other
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y

the
high-resolution
absorption
o-electron
of
y
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or
ys
imaging
is
[14

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ybrid
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allo
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great

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onding
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pixel
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sensor
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exist

dieren
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t
with
other
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pixel
photo

de
in
m
h
hannel
ybrid
has
design.
een
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bined
or
the
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readout
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MPEC
for


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to
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e
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as
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rst
efron
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sensors

the
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e
with
of
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energy
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er,
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gain
in
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ev
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ery
w
pixel.
sho
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to
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ork
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the
readout
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[6


andZ
K
et
tro
in

eect
Outline
used
The
length,
main
of
fo
y

la
of
hapter
this
5.2
thesis
from
is

an
bly
understanding
of
of
the
the
The
limitations
2.1.
of
la

sharing
pixel
detailed

Col
There
harges
are

three
hrotron
main
qualit

pro
limiting
imaging
the
high
p
unique

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of
measuremen


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material
y
giv
pixel


ot
?
eect


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oth
esolution
in
of
sharing.
the
Comp
Sensor
of
Material:
lifetime
The

energy
of
of
arious
the
y
absorb

ed
strain
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the
y
in
photon

is
high
transmitted

to
of
the
y

to
material
e
b
scattered
y
7

of
electrons.
of
The


ys
harge


the
are
hapter

exp
along

the
square
path
the
of
detrimen
the

electrons
with
and
kness.
not
ts
at
ulations
a
erimen
single
estigating
p

oin
Char
t.

Dep

ending

on
generated
the
insucien
material
mobilit
and

energy
5.1
,
the
the


for
tra
parameters.
v
oer
elled
ossiblities
b
estigate
y
The
the
and
electrons
the

b
b
b
e
w
a
estigated
few
of
tens

of



th
Medipix
us
with
limiting
qualit
the
industrial
spatial
sensor
resolution.
oers
Moreo
ossibilit
v
e
er,
a
Compton
of
scattering
b
and
the
esp
er.
ecially
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with
absorption
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with
orking
subsequen
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t
the
emission

of
een

the
photons
in
results

in
description
the


in
of
This
m
presen
ultiple
ts

of
electrons,
GaAs
th
ers.
us
ro
further
of

drift
the
the
spatial
tal
resolution
of
through
harge
the

o
the

thic
of
Chapter
m
presen
ultiple
b

sim
harge
and

exp
This
ts
eect
v
is
the
particularly
of
sev
harge
ere
?
for
ge
high-
le
In

,
ound
high
suer
atten

uation

materials,
the
with

1

b
y
-edges
t
inside
and/or
the
y

the
t
harge
sp
Chapter
ectrum.
fo
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on
mean

path
the
length
harge
of


v
photons

dep
Sync
ends

on
man
the
p
material,
to
but
v


b

e

more
y
than
the
some
on
10
assem


Chapter
y
2.1
bump
outlines
onding
the


ere

v
kground
b
for
means
the
ro
sim
king
ulations
e
presen
[17
ted
The
in
noise-free

range
hapter
the
4
readout
that
bined
in
the
v

estigate
y
those
the
eects.

?
as
Char
la
ge
er
Carrier
the
Diusion:
p
The
y
generated
observ


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w

v
diuse
eld
while
an
drifting
y
to
eam
the
inside

sensor

y

Chapter
If
summarises
t

w
ts
o
and
or
the
more
sensors.
pixel
w





y
the
and

in
harge
pro

b
one
w
sp
X-ra
eaks
and
of


is
ge
tro
sharing
in
.
hapter
This
A
limits
of
b
Medipix
oth
is
the
en
spatial

and
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energy

resolution
also
of
ts
the
erimen

and
As

the
Medipix1
diusion
with
width
sensor

y
with
2
theI
−μxI(x) =I e x μ0
Z
Z
Z
Z
atomic
Matter
energy
.
oth
.

.
X-ra
.
use,
.
thic
.
to
.
ely
.
with
3
the
2.1.1
m
P
range
assage
e
of
suitable
X-Ra
regions
ys
represen
through
energies.
Matter
X-Ra
.
atten
.
i.e.
.
y
.
a
.
is
.
X-ra
.
b
.
for
.
higher
.

.
CdT
.
Figure
.
pair
.
absorb
.

.
photo-electric
.
eect
.
tially
.
2.1
3
depth
2.1.2
dep
Photo-electric
and
Eect
b
.
elemen
.
example,
.
enden
.
passing
.
GaAs
.
gure
.
absorption
.
matter,
.
arious
.
A
.
m
.
up
.
b
.
ell,
.
.
.
of
.
lik
.
e
.
uation
.
the
.
eect,
.
a
.
er
.
energy
.

.
Compton
.
pair
4
t
2.1.3
y
Compton
for
Scattering
exp
.
and
.

.
ten
.
p
.
.
.

.
on
.
photon
.

.
n
.
y
.
ectiv
.
and
.
As
.
for
.
energy
.
absorption
.
b
.
300
.
of
.
CdT
.
wn
.
Comparing
.
enden
.
y
.
photons
.
suitable
6
the
2.1.4
materials
In
iden


of
300
Electrons
only
with
y
Matter
30
.
It
.
used
.
as
.
the
.

.
or
.
X-ra
.
energy
.
X-Ra
.
GaAs
.
should
.
hosen
.
higher
.

.
sho
.
e
.
the
8
eect
2.2

Signal
of
Generation
um
in
of

and
X-Ra
The
y
the

equal
.
photo-electric
.
resp
.
eect
.

.
is
.
lo
10
or
2.2.1
the
Num
dominan
b
in
er
energy
of
onen
Created
Electrons
Charge
ys
Carriers
of
.
In
.
ts
.
Con
.

.
enetration
.
rs
.
The
.
uation
.

.
ends
.
b
.
the
.
energy
.
material
.
osition,
.
atomic
.
um
.
er
11
of
2.2.2
resp
Diusion
e
of
ts
Charge
densit
Carriers
.
and
an
Charge
and
Sharing
later
.
the
.
dep
.
t
.
of
.
photon
.
eam
.
a
.
?
.
slab
.
Si,
.
or
11
e
This
sho

in
hapter
2.1.
presen
the
ts
dep
an
t
in
probabilit
tro
for

y
to
in

the
X-ra
energy
y
for

v
The

rst

part
e
of
tied.
this


of
hapter
kness
is
?
an
is
o
suitable
v
X-ra
erview
energies
of
to
the
k
in
V.


of
e
the
for

energies
t
w
X-ra
but
ys
absorption
and
drops
the
tly

F
electrons
the
with
of
the
ys

higher
medium.
,
In
high-
the
materials

e
part
and
of
e
this
b


hapter,
due
the
their
w
atten
orking


t.
of
2.2

ws
X-ra
relativ
y
dominance

of
is
photo-electric
in
Compton
tro
and

pro
2.1
as

function
of
the
X-Ra
n
ys
b
and

Electrons
the
with
er
Matter
photon
2.1.1
.
P
lines
assage
t
of
lo
X-Ra
of
ys

through
for
Matter
and
A
eect
mono
ectiv

Compton
hromatic
and
photon
pro
b
The
eam
eect
of
dominan
in
for
with
w
materials.
F
or
X-ra
ter
energies,
lik
photo-electric

is
Compton
t
is
high-
t
tensit
F
y
ligh
2
elemen
ts
passing
e
through
the
a
eect
slab
dominan
of
already
matter
the
is
y
atten
3
uatedabsorber thickness 300 um
1
Si
GaAs0.9
CdTe
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0 20 40 60 80 100 120
E in keV
E = hν
E =hν
E K
′E
′E = hν−E
L K
or
Si,
ucleus
GaAs
due
and
This
CdT

e
is
as
b
a
er
function
to
of
v
the
energies
photon
As
energy
the
.
the
regime.
subsequen
Ra
the
yleigh
The
scattering
the
is
of
an
shell.

sharp
pro


in
without
transfer
energy
energy
transfer
300
to
(2.1)
the
es
absorb
the
er.
electrons
Ho
surrrounding
w

ev
of
er,

the
the

shells.
of
whenev
the
photon

energy
t
ws
photon
for
is
of

photo-electric
hanged.
probabilit
This
for
scattered
slab
radiation

is
the
detri-
negligible
men
?
tal
electron
to
in
the
a
qualit
ejection
y
lea
of
ionized
X-ra

y
shell
images.
relled
P
an
air
or
pro
leading

of
is
X-ra
p
the
ossible
Auger
only
of
if
is
the
dierence
energy
energies
of
ectiv
the
photo-electric


t
the
photon

is
ab
ab
the
o
an
v
2.4
e
atten
1.024
photo-electric
Me
er.
V
at
and
and
therefore

not

further
absorption

y
here.
highest
2.1.2
electrons
Photo-electric
the
Eect
-shell.
The
the
absorption
energy
of
to
a
n
photon
is
of
the
energy
m
Figure
of
4
ejected

is
y
a
b
eam
y
photon
the
bind
b
The
ound
of
electrons
photo-electron
of
v
an
an
atom
atom.
and
v
the
in
subsequen
electron
t
is
emission
tly
of
with
an
from
electron
upp
is
shell

the
the
medium,
photo-electric
to
eect
emission
(see

also

gure
ys
2.3(a)).
to
The
ejection
n
an
ucleus
electron.
tak
energy
es
the
a
photon

equal
momen
the
tum
of
and
binding
a
of
photo-electron
resp
from
e
the
The
atomic

shell

is
tly
emitted.
er
This
energy
is
the
only
t
p
rises
ossible
o
if
e
the
binding
photon
of
energy
atomic
X-Ra
Figure

sho
2
the
Absorption
uation
is
to
larger
absorption
of
silv
-edge
The

steps
A
the
appro
-edges

e
than
are
the
visible.
smallest
Born
binding
ximation
energy
b
2.1:
used
for
non-relativistic
bind
to
of
the
the

shell
[20
electrons.
The
Fraction of absorbed Intensityhν
Z
τ σ
κ
7
2 2 2√ 8πr m cee5Φ ≈ 4α 2Z
3 hν
− −
e e
hv
hv’
photo-electric
and
[18
the
eect
atomic
as
n
Figure
um

b
the
er
and
In
the
of
Electrons
the
pair
absorb
photon
er.
the
The
function
lines
pro
represen
Compton
t
regions
the
Plot
lo
with

(a)
of
X-Ra
equal
pro

(

)
for

the
photo

of
of
a
Compton

Figure
pair
Sc
eect
eect
eect,
Compton
of
tering.
dominance
energy
of
)
2.2:
resp
Matter
ectiv
(2.2)
ely
and
the
Photo-electric
Compton
ys
eect
and
photo-electric
(b)
(
scattering
2.1
2.3:
illustrations

the
of
)
photo-electric
and
and
Compton
scat-
eect
5
(attenuation due to photo−electric absorption (Ag)
4
10
L−edges
3
10
2
10 K−edge
1
10
0
10
0 1 2
10 10 10
E in keV
α
Z
me
2
ere 24πǫ m ce0
c
5Z
−7/2(hν)
′ν
ν
′ν =
1+γ(1−cosθ)
to
tten

A
Compton
2.4:
of
Figure
means
uation

materials
(2.3)

6
scattering.

electron
y
as
X-Ra
the
sp
gure
eed

of
2.1.3
ligh
photon
t
shell
Close
energy
to
the
the
v
edges

the
Figure
ab
The
o
atomic
v

e
therefore
equation
preferred
2.2
since
needs
is
to
Scattering
b
of
e
an
m
outer
ultiplied

b
the
y
high
a
energy

the

ximation
to
whic

the
date
e
the
tially

illustrates
in
pro
the
n

photon

t
(see
silv
[20]
er
for
2.2),
details).
high-Z
In
are
general
as
the
material

their


of
higher.
the
Compton
photo-electric
The
eect
scattering

a
with
on
the
electron
atomic
the
n
atomic
um
is
b
Compton
er
If
(
photon

is
2

radius
the
binding
and
of

electrons,
with
free
the
appro
energy
is
(
alid

h
due
that
to
electrons
mass
b
electron

photo-electric
essen
absorption
free.
er
2.3(b)
).
a
The
scattering
b

electron
frequency
um
is
of
the
scattered
dominan
is:
t
for
absorption

eect
ne
for
with:
X-ra
[19
ys
(see
photo-electric
eect
)
2
attenuation (cm /g)