修士論文 位置分解能とエネルギー分解能に優れた ピクセル型CdTe ...

CdTe
ISAS/JAXA
oonuki@astro.isas.jaxa.jp
2005 1

ii
X
(CdTe) CdTe
CdZnTe NaI
CdTe/CdZnTe Si
5 mm 100 keV
()
2 5 mm CdTe/CdZnTe
662 keV FWHM 20 keV (3%)
X 500 µm
1056 CdTe 60 keV
0.9 keV (FWHM) CdTe

iii
1 3
2 CdTe/CdZnTe 7
2.1 CdTe/CdZnTe . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2 Shockley-Ramo . . . . . . . . . . . . . . . . . . . 7
2.3 . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
2.4 . . . . . . . . . . . . . . . . . . . . . . 11
2.5 . . . . . . . . . . . . . . . . . . . . . . . 14
3 CdTe 15
3.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.2 . . . . . . . . . . . . . . . . . 18
3.2.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
3.2.2 µτ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.2.3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
3.4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
3.5 . . . . . . . . . . . . . . . . . 27
3.6 . . . . . . . . . . . . 28
4 X 31
4.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.2 X . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.2.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
4.2.2 CdTe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
4.2.3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
4.2.4 LSI . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
4.2.5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
4.3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
4.3.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
4.3.2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
4.3.3 . . . . . . . . . . . . . . . . . . . . . . . . . 38
4.3.4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
4.4 . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
4.4.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
4.4.2 HV . . . . . . . . . . . . . . . . . . . . . . . 42
4.4.3 . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
4.5 . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
4.6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
4.7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
4.8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54

iv
5 55
A 5mm 8 × 8 CdTe 57
A.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
A.1.1 8 × 8 CdTe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
A.1.2 VA32TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
A.1.3 VA32TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
A.2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

v
1.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2 . . . . . . . . . . . . . . . . . . . . . . 8
2.3 CdTe . . . . . . . . . . . . . . . . . . . . . . . 9
2.4 CdTe . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.5 . . . . . . . . . . . . . . . . . . . . . . . 11
2.6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
2.7 . . . . . . . . . . . . . . . . . . . . . . . 13
2.8 . . . . . . . . . . . . . . . . . . 13
2.9 / (W/L ) . . . 13
2.10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.2 . . . . . . . . . . . 17
3.3 . . . . . . . . . . . . . . . . . . . . . . . 17
3.4 . . . . . . . . . . . . . . . . . . . . . 18
3.5 µτ . . . . . . . . . . . . . . . . . . 19
3.6 µτ . . . . . . . . . . . . . . . . 19
3.7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
3.8 −20 ˚C 137 Cs 133 Ba . . . . . . . . . . . . . . . . . . . 21
3.9 −20 ˚C 137 Cs . . . . . . . 22
3.10 . . . . . . . . . . . . . . . 23
3.11 662 keV . . . . . . . . . . . . . . . . . . . . . . . 24
3.12 137 Cs . . . . . . . . . . . . . . . . . . . . . . . . . . 25
3.13 2 . . . . . . . . . . . . . . . . . . . . . . 26
3.14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
3.15 (C.I.E.) . . . . . . . . . . . . . . . . 28
3.16 W/L . . . . . . . . 29
3.17 W/L . . . . . . . . . . . . . . . 29
4.1 CdTe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
4.2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
4.3 22 × 44 CdTe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
4.4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
4.5 . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
4.6 ASIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
4.7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
4.8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
4.9 −20 ˚C−50 ˚C 241 Am . . . . . . . . . . . . . . . 39
4.10 −50˚C 57 Co . . . . . . . . . . . . . . . . . . . 40

vi
4.11 . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
4.12 . . . . . . . . . . 43
4.13 . 43
4.14 . . . . . . . . . . . 44
4.15
. . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
4.16
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
4.17 . . . . 46
4.18 241 Am . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
4.19 60 keV (FWHM) . . . . . . . . . . . 49
4.20 60 keV 2 . . . . . . . . . . . . . . . . . . . 49
4.21 60keV . . . . . . . . . . . . . . . . . . . . . 49
4.22 60 keV . . . . . . . . . . . . . . . . . . . . . . . . . 50
4.23 60 keV . . . . . . . . . . . . . . . . . . 50
4.24 60 keV () () . . . . . . . 50
4.25 60 keV 2 . . . . . . . . 51
4.26 60 keV . . . . . . 51
4.27 1 1 . . . . . . . . . 52
4.28 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
4.29 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
A.1 8 × 8 CdTe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
A.2 8 × 8 CdTe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
A.3 8 × 8 CdTe I-V I-T . . . . . . . . . . . . . . . . . . . . . . . . 58
A.4 CdTe . . . . . 59
A.5 VA32TA . . . . . . . . . . . . . . . . . . . . . 61
A.6 57 Co . . . . . . . . . . . . . . . . . . . . . . 62
A.7 57 Co . . . . . . . . . . . . . . . . . . 62
A.8 −40 ˚C 57 Co . . . . . . . . . . . . . . . . . . . 63
A.9 −40 ˚C 57 Co . . . . . . . . . . . . . . . . . . . . . . . 63

1
1.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
4.1 Caltech ASIC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
4.2 Cd Te X . . . . . . . . . . . . . . . . . . . . . . . . . 41
4.3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42

3
1
X
X
2010 NeXT
X 12
X
Astro-E2 X (2005 ) 1 - 2
10 keV MeV X
X
NaI
10 eV
662 keV 6 %
1mm
X Si Ge
eV
100 µm
Si X
Ge
0.67 eV
NeXT X
X
(CdTe) CdTe 10 %
(CdZnTe) 34II-VI
(Z Cd =48, Z T e =52) ( 1.1) 1.1 NaI
THM CdTe
2627 1.5 eV
ADCRORAD Traveling
Heater Method (THM) p CdTe
7 cm 5678
CdZnTe 1.6 eV 10 10 Ω · cm
eV products High Pressure Bridgman
(HPB) CdZnTe 9CdZnTe HPB
41011
CdTe CdZnTe (µ) (τ)

4 1
1.1: NIST12
ɛ (µτ) e (µτ) h
Z [ g/cm 3 ] [ Ωcm ] [ eV ] [ eV ] [ cm 2 /V ] [ cm 2 /V ]
CdTe 48/52 5.85 ∼ 1 ×10 9 1.4 4.43 ∼ 2 × 10 −3 ∼ 1 × 10 −4
CdZnTe 48/30/52 5.81 ∼ 3 ×10 10 1.6 4.6 ∼ 1 × 10 −3 ∼ 3 × 10 −5
Si 14 2.33 1 ×10 3 1.12 3.61 0.42 0.72
Ge 32 5.33 1 ×10 2 0.72 2.98 0.22 0.84
ɛ :
µτ :
1.1:

()
100 keV
5 mm
Luke
13
(
)
21
2
CdTe/CdZnTe 3 5mm CdTe
4
100 keV X 0.5 – 1.0 mm CdTe/CdZnTe X
114100 keV 1 keV(FWHM)
CdTe/CdZnTe 5 CdTe
500 µm
5

7
2
CdTe/CdZnTe
2.1 CdTe/CdZnTe
X
CdTe/CdZnTe
2.2 Shockley-Ramo
X
ɛ 1.1
E
S :
∮
Q = ɛE · dS (2.1)
S
ɛ ()
() Shockley-Ramo
(Weighting Potential) (Weighting Field)
1516
∇ 2 φ = ρ ɛ
(2.2)
1. φ 1
2. 0
3. ρ = 0
3 2.2

8 2 CdTe/CdZnTe
γ
e e
e
h h
h
φ 0 (Weighting Potential)
e-
h
electron
component
hole
component
z = Z
Cathode
Anode
Cathode:
Common. Electrd.
Anode:
Pixel
2.1:
2.2:
1
Shockley-Ramo i Q
i = dQ = qv · E(x) (2.3)
dt
Q = −q · ∆φ(x) (2.4)
q v E(x) φ(x) x
(Weighting Field) (Weighting Potential) 2
Q q
∆φ
Shockley-Ramo
Frisch grid
131719

2.3. 9
electron
component
total
efficiency
η
hole
component
Cathode:
Common. Electrd.
Anode:
Pixel
2.3: CdTe
2×2mm 2 0.5mm
30V0.001[cm 2 V −1 ]µτ h 0.0001[cm 2 V −1 ] Hecht
2.3
CdTe CdZnTe (µ) (τ)
2.4
Q =
∫ xend
x init
q(x)E(x) · dx (2.5)
q(x) x
z = Z
( )
|z − Z|
q(z) = ±ne 0 exp − (2.6)
λ
n e 0 λ
(µ [cm 2 /V −1 s −1 ]) (τ[s])
(E [V cm −1 ])
λ e,h = (µτ) e,h E (2.7)
2.1
E = −1/L (2.8)
L
2.2
2.6 2.5
Q e (Z) = ne 0
L
Q h (Z) = − ne 0
L
∫ zfinal
z
∫
init
zfinal
z init
(
exp − z − Z )
dz
λ e
(
exp − Z − z ) (2.9)
dz
λ h

10 2 CdTe/CdZnTe
2.9
η(Charge Induction Efficiency)
η(Z) = Q = λ ( (
e
1 − exp − L − Z ))
+ λ (
h
1 − exp
(− Z ))
(2.10)
ne 0 L
λ e L
λ h
Hecht 20Hecht
(η) (µτE) CdTe/CdZnTe
(µ) (τ) Z
2.3 0.5 mm CdTe 30 V
() ( 2.4) X
( 2.5)
CdTe 10 9−10 Ω · cm
0.5 mm 100 V
100 keV
5 mm
2.4: CdTe 241 Am 60 keV
× 2 mm 2 0.5 mm
20 ˚C 30 V

2.4. 11
0.5mm thick
η
2mm thick
5mm thick
2.5:
0.5 mm2 mm5 mm 1600 V/cmµτ e 0.001 cm 2 /V
µτ h 0.0001 cm 2 /V Hecht
2.4
212219
2.6
W L
(W ≤ L) a 25W
2.6
1
1. z = L φ(x, y, L) = φ L (x, y) 1
0
2. z = L φ(x, y, z) = 0
3. ρ = 0
φ(x, y, z) = X(x)Y (y)Z(z) (2.11)
1 x,y
y φ(x, z) = X(x)Z(z)
coplanar 23

12 2 CdTe/CdZnTe
y
Cathode:
Common Electrode
Anode:
Pixel Electrodes
γ
a
e e
e
h h
h
W
z
x
L
2.6:
φ(x, y, z) =
∞∑
n,m=1
A m,n sin(α n x) sin(β m y) sinh(γ n,m z) (2.12)
α n = nπ a , β m = mπ
a , γ n,m = √ α 2 n + β 2 m
A m,n 1
4
A n,m =
a 2 π 2 sinh γ n,m L f m f n (2.13)
( mπ(a + W )
f m = cos
− mπ(a − W ) )
( nπ(a + W )
, f n = cos
− nπ(a − W ) )
2a
2a
2a
2a
W L (W/L ) 0.4 2.7
2.12 nm
n = m = 500
n m
2.7 2.8 4
2.9
W L (W/L )
( W/L=inifinity)
W/L

2.4. 13
d = 0.7 (W/2)
d = W
φ 0 (Weighting Potential)
Pixel
d = 0 d = 1.3 (W/2)
d = 0
d = 0.7 (W/2)
d = 1.3 (W/2)
d = W
Cathode:
Common. Electrd.
Anode:
Pixel
2.7:
W/L 0.4
2.8:
φ 0 (Weighting Potential)
W/L = infinity.
W/L = 1
W/L = 0.4
W/L = 0.2
W/L = 0.1
Cathode:
Common. Electrd.
Anode:
Pixel
2.9: (L)
(W)

14 2 CdTe/CdZnTe
2.5
CdTe/CdZnTe 100keV
(Sigle Polarity Charge Sensing Technique)
Luke 1324 2.10
( A B)
( A)
A B
(φ A − φ B ) 0
5mm CdZnTe 122keV 4keV(FWHM)
1718
Barrett 21
()
W/L 2.9
5mm 2.2 mm CdTe 122 keV
6 keV(FWHM) 221925
µ τ
3 5 mm
4
γ
C
e e
e
h h
h
Q
A
Q
φa
B
φb
φa − φb
2.10:
φ a − φ b

15
3
CdTe
5 mm CdTe
137 Cs 662 keV
20 keV(3 %)
3.1
CdTe/CdZnTe
µ τ
µτ µτ
28
N
µτ
Hecht (2.10)
z = Z
zi = (Z/L) · N 2.12 2.4
η =
N∑
i=zi
(
exp − i − zi )
(φ[i + 1] − φ[i]) +
λ e
1∑
i=zi
(
exp − zi − i )
(φ[i] − φ[i − 1]) (3.1)
λ h
3.1 2.10 3.1
(∆z = (L/N)) ∆t
∆t = ∆z
µE
2.10 3.1
3.1
THM CdTe µ
(3.2)

16 3 CdTe
Input W, L.
Loop through z from 0 to L
Calculate Weightng Potential: φ(z)
Input E, (µτ)e, (µτ)h, µe, µh
Parameters and contents.
W : pixel size
L : thickness of the detector
φ(z) : weighting potential at depth z
E : strength of electric field
(µτ)e : product of electron
(µτ)h : product of hole
µe : mobility of electron
µh : mobility of hole
Loop through z from 0 to L
Calculate Induced Charge:
Qc(t) and Qp(t)
at time t.
Output.
Qc(t) : induced charge on common elctrd.
for each depth.
Qp(t) : induced charge on pixel elctrd.
for each depth.
Output Time Profile of
Induced Charge: Qc(t) & Qp(t)
for each depth.
3.1:
τ
41027
µτ 0.0025
cm 2 /V 0.0001 cm 2 /V (µ) 1400 cm 2 /V·s 75 cm 2 /V·s
1633 V 1000 V
4 × 4 CdTe
3.2
(z=0)
3.3 µs
3.3

3.1. 17
z = 0
z = 2.5 mm
z = 1.25 mm
z = 3.75 mm
z = 4.5 mm
z = 3.75 mm
z = 4.5 mm
z = 2.5 mm
z = 1.25 mm
z = 0
3.2: () ()
electron
component
total
efficiency
electron
component
total efficiency
hole
component
hole
component
Cathode:
Common. Electrd.
Anode:
Pixel
Cathode:
Common. Electrd.
Anode:
Pixel
3.3: () ()

18 3 CdTe
collecting time for Pixel:
0.5 µs
2 µs
10 µs
HV = 1000V
(µτ)e = 0.0025
(µτ)h = 0.0001
collecting time:
Common : 0.5µs
3.4:
2
3.2
3.2.1
5 mm
µs
4 × 4 CdTe 2 µs
3.2
0.5 µs2 µs10 µs 3.4
0.5 µs
0.5 µs 2 µs

3.2. 19
HV = 1000V
(µτ)h = 0.0001
(µτ)e = 0.005
(µτ)e = 0.0025
(µτ)e = 0.001
(µτ)e = 0.0005
collecting time:
Common : 0.5µs
Pixel : 2.0µs
HV = 1000V
(µτ)e = 0.0025
(µτ)h = 0.0001
(µτ)h = 0.0005
(µτ)h = 0.00001
(µτ)h = 0
collecting time:
Common : 0.5µs
Pixel : 2.0µs
3.5: µτ
µτ
3.6: µτ
3.2.2 µτ
µτ e (λ)
3.5 (µτ) e
(µτ) h
3.6 (µτ) h
3.2.3
(µτE) E (µτ) e,h
(µτ) e,h
3.7
2000 V x
1000 V

20 3 CdTe
2000V
1000V
500V
250V
(µτ)h = 0.0001
(µτ)h = 0.0025
collecting time:
Common : 0.5µs
Pixel : 2.0µs
3.7:
x
3.3
µτ e µτ h
µτ e,h
3.8
−20 ˚C1000 V 0.5 µs
2.0 µs 137 Cs 133 Ba 662 keV
356 keV303 keV µτ e
0.0025 cm 2 /Vµτ h 0.0001 cm 2 /V
16 ( 3.9)
1000V

3.3. 21
3.8: −20˚C 137 Cs 133 Ba 137 Cs 662 keV 133 Ba 356 keV
303 keV 1000 Vµτ e
0.0025 cm 2 /Vµτ h 0.0001 cm 2 /V 0.5 µs 2 µs

22 3 CdTe
3.9: 500V() 250V() −20˚C 137 Cs
3.8

3.4. 23
3.4
x
662 keV 3.8
137 Cs 50 keV
3.10 662 keV
662 keV ( 3.11) 3.12
21.2 keV
100 – 200 keV 662 keV
(S com ) (S pixel )
(S com /S pixel ) 0.4 ( 3.12)
74 %
3.10: 50 keV
662 keV

24 3 CdTe
3.11: 662 keV () ()
662 keV 662 keV

3.4. 25
3.12: () ()
S com /S pixel >0.4
0.4

26 3 CdTe
2
31
S pixel =
S pixel
1 − exp(−P 1 S com /S pixel ) − P 2 S com /S pixel
(3.3)
S pixel S com P 1 P 2
2
3.13 2 ( 3.8) x
P 1 11.25P 2 0.025
3.12 S com /S pixel
3.13: 2

3.5. 27
3.5
2
CdTe/CdZnTe
1517343
3.3
3.14()
3.3 3.14()
3.14: ()

28 3 CdTe
3.6
x
x
3.15 5 mm
3.16 5 mm CdTe ()
2 % ()
W/L 5 mm
W/L 0.4
3.17 2 mm
W/L 0.15 300 µm
2000 V/cmµτ e 0.0025 cm 2 /V µτ h 0.0001 cm 2 /V
0.5 µs 2 µs
W/L = 0.2
W/L = 0.3
W/L = 0.4
W/L = 0.8
3.15: (C.I.E.)

3.6. 29
3.16: 5 mm CdTe W/L
2 %
3.17:

31
4
X
4.1
NeXT X (HXI) 250 µm 1 keV
1
200 µm
X
200 µm 1024 1021
2 mm CdTe
VA32TA 60 keV 1.6 keV(FWHM)
35NeXT-HXI
500 µm CdTe
X
(Caltech) CdZnTe
1.3 × 2.5 cm 500µm 2 LSI( ASIC)
CdTe
4.2 X
4.2.1
ASIC CdTe (4.1)
CdTe 2 ASIC
X 4.2(a)
CdTe ASIC12bit ADC(ADC12062)
ASIC FPGA(Actel A54SX72A)
( MISC 1 ) (14.7456 MHz) 3 128kB SRAM (IDT71027)
4.2(b)
ASIC ADC MISC
RS-422 PC
1. : +5.0 V+2.5 V
2. : +5.0 V+0.5 V
1 Minimal Instruction Set Computer

32 4 X
3. : +0.5 – 2.5 V
4. : +0.1 – 0.5 V
5. : ±10 V +5.0 V
4.2.2 CdTe
CdTe 4.3 CdTe
Pt 2.5 × 1.5 cm 2 0.5 mm
448 µm
50 µm 24 × 44 1056
4.2.3
CdTe
ASIC
CdTe (Au)
(In) (125 ˚C ) (20 g/pixel)
3 25 µm
35 – 50 µm 1
2 – 5 µm CdTe
In ASIC
4.1:

4.2. X 33
stud
bump
CdTe
ASIC
ADC
MISC FPGA
CdTe
ASIC
ADC
CLK
3x128kB SRAM
CLK
MISC
SRAM
Level Shifters
PC
Level Shifter
(a)
(b)
4.2: (a) (b)CdTe
ASICADCFPGA (MISC FPGA)SRAM
DETAIL
DETAIL
4.3: 22 × 44 CdTe 1.29× 2.36 cm 2 0.5 mm
498 µm 448 µm
4.2.4 LSI
4.2.4.1
CdTe ASIC(Caltech ASIC)
(Caltech) VLSI 3637Caltech ASIC
High Energy Focusing Telescope (HEFT) Constellation-X
X 4.1 ASIC
ASIC
4.2.4.2
Caltech ASIC

34 4 X
pixel 498 µm
chip 1.3 × 2.5 cm 2
24 × 48
50 µW/pixel ( 50 mW/chip)
2 %(5.5 %)
FWHM: 300 eV (@ 0 pF)(10 %)
4.1: Caltech ASIC
4.4 – 4.5
100 ns 30 µs 16
1µs
1 µs
8 µs ASIC
ADC
4.6 ASIC
DSP
4.2.4.3
Caltech ASIC (Charge Sharing)
ASIC
8 9
() 18 2
1 18
× 16 288 ADC A/D 12bit ADC
0.5KBytes
4.2.5
Caltech ASIC
1.
1.0 %
2 2
10 3 5

4.2. X 35
+5V
signal
input
40fF
CSA
0.5pF
shaping
amp.
disc.
trigger out
test pulse
input
10fF
1pF
0.5pF
to ADC
16 capacitors / pixel
readout busses
(1 / pixel row)
readout
amp
4.4: ASIC CSA
s(t)
s(t)
s(t)
t
t
t
CSA
i(t)
shaping
amp.
disc.
trigger
MUX
s(t)
t
4.5: CSA
16

36 4 X
4.6: ASIC ASIC 16 A/D
2. 9 16 µs
ADC
3. ASIC
4.6 6 ADC
6
5 keV
4.
5.
4.3
4.3.1
HV ASIC ASIC
1ch(row=11, col=22) ON/OFF

4.3. 37
6
4.3.2
ASIC
HV OFF
0.1 – 0.3 V MISC
MISC ON/OFF
20˚C −20˚C 10 × 8
0.1 V CdTe 27 keV 4.7 20˚C
856 ± 46 eV (79 e − ) −20˚C 650 ± 39 eV
(60 e − ) ASIC
CdTe ASIC
CdTe
ASIC 4.7
CdTe
7
400 eV ENC 37 e − Caltech
4.7: 20˚C −20˚C
CdTe ()
37 e−

38 4 X
4.3.3
CdTe 10 9 cm ·Ω
ASIC
4.4 CSA
−20˚C−50˚C KEITHLEY237
4.8 100 V −20 ˚C
150nA −50˚C 3.3 nA
−20˚C 100 pA/pixel −50˚C
3 pA/pixel ASIC
100 pA/pixel −20 ˚C 100 V −50 ˚C 300 V
4.8:
4.3.4
HV
4.9 −20
˚C −50˚C
100 V −20˚C −50˚C 10˚C −50˚C
14 keV 60 keV 0.67 keV
0.89 keV
CdTe (Charge Induction Efficiency:C.I.E.)
CdTe (µ) (τ) ( µτ )
4.9 ()
µτ

4.3. 39
4.9: −20 ˚C−50 ˚C 241 Am

40 4 X
−50˚C 57 Co HV
4.10 40 V100 V300 V
40 V 122 keV
300 V
122 keV
C.I.E.
122 keV
300 V 1.47 keV
14 keV 40 V
0.61 keV CdTe
µτ
4.10: −50˚C 57 Co
40 V100 V300 V
40 V 14 keV 0.61 keV(FWHM)
122 keV 300 V 1.47 keV(FWHM)

4.4. 41
X [keV] CdTe [µm]
Cd K α 23.13 128
Cd K β 26.11 180
Te K α 27.37 64
Te K β 31.00 88
4.2: Cd Te X
4.4
250 µm
500 µm
4.4.1
4.12
−50˚C 57 Co
4.11
2 57 Co 122 keV 14 keV
y=0
4.12
5 keV
Cd Te K (fluorescence yield) 80 %
X
4.2 Cd Te X
500 µm X
4.13
97 keV 23 keV 97 keV
X 99 keV(=122 keV − 23 keV
) 95 keV(=122 keV − 27keV) 23 keV
Cd Te X

42 4 X
4.11:
4.4.2 HV
X
4.10 40 V,100 V,300 V 200 V
2
40 V 10660 (53.3%) 7732 ( 38.7%) 1203 ( 6.02%) 405 ( 2.03%)
100 V 12534 ( 62.7%) 6559 ( 32.8%) 639 ( 3.20%) 265 ( 1.32%)
200 V 13183 ( 65.9%) 6023 ( 30.1%) 575 ( 2.88%) 219 ( 1.10%)
300 V 13225 ( 66.1%) 5964 ( 29.8%) 598 ( 2.99%) 173 ( 0.865%)
4.3: −50 ˚C 57 Co
20000 4.3
5 keV
4.14 2 2 20000
40 V 47 %
200 V
66 %2 33%
4.4.3
Geant4
0.5 mm 25 × 15 mm 2 CdTe 40 cm
57 Co CdTe

4.4. 43
4.12: () ()122keV
4.13: ()
()

44 4 X
4.14:
50610
42217(83.4 %)2 8258(16 %)3
134(0.3 %)4 1 4.15 4.16
122 keV X
2 122 keV
X
16.6 %

4.4. 45
4.15:
4.16:
() ()

46 4 X
4.17:

4.5. 47
4.5
500 µm
µτ
µτ µτ
428
241 Am 40 cm
−50˚C 300 V
2.8 % 4.1 36 4.18 7 × 7
60 keV
1.0 keV(FWHM) 4.19
1.04 keV 0.10 keV 4.20
ADC 4.21 0.82 %
327
60 keV
4.22 45 keV 65 keV
8.9 % 1.1 %
327
60 keV () (
) 4.23 60 keV
4.24 60 keV
µτ
(DAQ)
4.26 ()
45 keV 65 keV
2.1 % 1.3 %

48 4 X
4.18: 241 Am 7 × 7 () ()

4.5. 49
4.19: 60 keV (FWHM)
1.04 keV 0.10 keV
4.20: 60 keV 2
4.21: 60 keV
σ=0.82 %

50 4 X
9500
9000
8500
total counts
8000
7500
7000
6500
6000
5500
5000
2500 3000 3500 4000 4500
60 keV peak counts
4.22: 60 keV
8.9 %
4.23: 60 keV
4.24: 60 keV () ()

4.5. 51
4.25: 60 keV 2
4.26: 60 keV
2.1 %

52 4 X
4.6
CdTe CdZnTe 3
Pt CdTe
26
−50˚C 100V
241 Am 4.27
60keV
20keV −20˚C
4.27: −50˚C100 V 1
4.7
500 µm 4.28
4.29(a) 70 mm 0.8 mm
241 Am 57 Co 80 V
4.29(b)(c) 4.29(b) 241 Am 13 – 26 keV
4.29(c) 57 Co 122 keV
500 µm
100 keV

4.7. 53
Source
40cm
Mask
8mm
CdTe
hold stage
detector box
4.28: CdTe
(a) mask photo
(b) 13 — 26 keV
(c) 105 — 130 keV
4.29: (a) (b)(c)
(b) 13 – 26 keV 241 Am (c) 105 – 130 keV
57 Co

54 4 X
4.8
CdTe 2 ASICIn/Au 500 µm
−50 ˚C 14 keV
60 keV 0.67 keV 0.89 keV (FWHM)
40
%
0.82 %
1056 ch 1.04 keV 60 keV
8.9 % CdTe
DAQ
2.1%
1 40 ms 25 Hz
20 ms 50 Hz MISC FPGA
FPGA
1 mm CdTe
(W/L ) 0.4
4

55
5
CdTe/CdZnTe
4 × 4 CdTe -20˚C 1000V
662keV 20keV
µτ
X CdTe 1056
500µm 14keV
0.61keV
1mm

57
A
5mm 8 × 8 CdTe
A.1
LSIVA32TA 5mm CdTe
CdTe
A.1
CdTe (Fanout
Board) ASIC VA32TA 2 FEC
ASIC
A.1: 8 × 8 CdTe 8×8CdTe
(Fanout Board) (FEC) ASIC:VA32TA
A.1.1
8 × 8 CdTe
CdTe A.2 Pt
8 × 8 64 2 mm
50 µm 1 mm
(I-V) I-T A.3
I-T −20 ˚C
−20 ˚C
1000 V 30 nA

58 A 5mm 8 × 8 CdTe
A.2: 8 × 8 CdTe
A.3: 8 × 8 CdTe I-V I-T

A.1. 59
A.1.2
VA32TA
CdTe VA32TA A.4
() CdTe In/Au
VA32TA
5 Fanout
A.4: CdTe
HV
A.1.3
VA32TA
VA32TA IDEAS ASIC
VA32TA 0.35 µm CMOS
32 ASIC
(DSSD) CdTe 8 × 8 CdTe
35 20 MRad
38
VA32TA 35 VA32TA A.5
VA32TA VA TA VA µs
(slow shaper)VA
TA 300 nsec (fast shaper)
OR
+1.5 V−2.0 V+1.5 V−2.0 V
500 µA
A.5 VA32TA TA delay
delay slow amp

60 A 5mm 8 × 8 CdTe
2 µs VA32TA
32
A.2
CdTe VA32TA VA-DAQ
VA32TA FEC
64ch A/D
1. ()
2.
3. ()
ADC 60 ch (10 keV )
4.
57 Co A.6 −20 ˚C
1000 V VA32TA 2 µs
(FWHM) A.8 −40 ˚C 57 Co
A.9 6.0 keV(FWHM)

A.2. 61
Input
Buffer
S/H
Semigaussian
fast shaper
+
fixed width
CSA
Semigaussian
slow shaper
other 31 channels
.............
Multiplexer
Level-sensitive
Discriminator
other 31 channels
.............
Wired OR
VA
Analog
OUT
Threshold
TA
Trigger
OUT
slow shaper
threshold level
fast shaper
ta
hold_b
shift_in_b
clock_b
.........
shift_out_b
analog out
ch0 ch1 ch2 ch3
.........
ch30 ch31
A.5: VA32TA () ()VA32TA TA
delay VA

62 A 5mm 8 × 8 CdTe
A.6: 57 Co −20 ˚C1000 V
A.7: 57 Co

A.2. 63
A.8: −40 ˚C 57 Co 1000 V
A.9: −40 ˚C 57 Co 1000 V

65
2
241 Am
CdTe
1

67
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