Transcript Status of Strip Detectors

Upgrade Silicon Strip Detectors (SSD)
Hartmut F.-W. Sadrozinski
SCIPP, UC Santa Cruz
Status
Pre-Rad Testing
Post-rad Testing
Protons
Neutrons
Gammas
Preparation for Modules/Staves
Work shared by UCSC, BNL, SUNY, NYU, KEK, Tsukuba, Liverpool,
Cambridge, Lancaster, Ljubljana
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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SSD Development for ATLAS Upgrade Tracker
KEK
Tsukuba
Liverpool
Lancaster
Glasgow
Sheffield
Cambridge
Share expertise and cost within the ATLAS groups
Leverage rad-hard experience with p-type SSD
(RD50, KEK)
Sensor fabrication with the only viable large-volume
and high-quality manufacturer (HPK)
Produce proto-type test structures
(radiation damage, isolation, ..)
Produce full-size sensors to support module/stave
program (stereo, bonding, gluing, thermal
management, ..)
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
QML
Freiburg
MPI
Ljubljana
Prague
Barcelona
Valencia
Santa Cruz
BNL
PTI
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ATLAS07
Purpose
–
–
Full square for Modules/Stave
Use in 2008
Delivery target
–
–
–
Pre-series Feb. 2008
2nd Pre-series Sep. 2008
Production Dec 2008
Wafer
–
–
150 mm p-FZ(100)
320 µm thick
n-strip isolation
–
–
–
Individual p-stop
P-spray
P-spray + p-stop
Stereo
–
–
–
40 mrad
Integrated in half area
Dead area: 2 mm
Strip segments
–
–
4 for SS (but still true for 4%
limit?)
LS: segments wire-bonded
•
Strip segments
–
–
4 for SS (but still true for 4% limit?)
LS: segments wire-bonded
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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Status of ATLAS07
• After testing of pre-series:
– ATLAS07M - with modified masks
• Edges of the bias ring of the stereo strips
• Zone4 PTP structures: 4 types
• Zone2 mistake corrected
– Fabrication in process
• 2nd Pre-series
• Delivery: Mid Sep.
• Study of p-spray dose by HPK
• Order of "Al-metal" dummy sensors
• Limited number of “mechanical samples”
Aug. 12, 2008
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
ATLAS07 p-type mini-SSD
•
•
•
•
•
6-inch (150 mm) wafer
Maximum size sensor (~10 cm x ~10 cm)
Prototyping simultaneously both short and long
strips
Prototyping simultaneously both axial and
stereo strips
R&D 24 Test structures (“Zones”)
– Candidate isolation structures
– "Punch-thru Protection" structures
– Wide/Narrow metal effect
– Wide/Narrow pitch effect
– P-spray vs. P-stop vs. combined
3 Isolation schemes on wafers with and without p-spray
Wafers 1-17 with p-spray, 20 – 30 no p-spray
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
26 Monitor Diodes
4mm x 4 mm
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ATLAS07 Specification
Wafer size
Thickness
Orientation
Type
Ingot
Resistivity
Outer dimension
Sensitive implant edge dimension
Strip segments
Strip segement length (approximate)
Strip implant
Strip pitch (round of 0.5 µm)
Strip implant Width
Strip bias resistor
Strip bias resistnace (Rb)
Strip readout coupling
Strip readout metal
Strip readout metal width
Strip AC coupling capacitance
Strip isolation
Strip isolation method
Gap between strip segments
Microdischarge onset voltage
Maximum operation voltage (*)
Leakage current
Radiation tolerance
ATLAS07
150 mm
320 µm
<100>
P
FZ
>2 kΩcm
97.54x97.54 mm2
95.58x95.58 mm2
4
23.82 mm
N
74.5 µm
16 µm
Polysilicon
1.5+/-0.5 MΩ
AC
Pure Aluminium
20 µm
>20 pF/cm
>10xRb at 200 V
Narrow-common p-stop
<160µm (rail)
<70µm (no rail)
>200V and <2% bad strips
<500 V
600V
<200 µA at 500 V
9x1014 1-MeV neq/cm2
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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ATLAS07 Order: 132 Wafers
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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ATLAS07 Pre-Series
Verify Masks
Verify Specifications
Chose Isolation schemes?
Initial Verification of Radiation Hardness
Start Module/ Stave construction
Wafer
Isolation
Number of wafers
p-stop
6
Miniatures
No structure (PTP)
p-spray (NS-PTP)
p-spray (No PTP)
p-spray (NC PTP)
Individual
Narrow common
Narrow C (PTP)
Narrow Metal
Wide pitch
72
6
18
24
12
6
6
72
FZ1
p-spray
+p-stop
9
p-spray
only
0
108
0
9
0
0
0
27
36
18
9
9
108
0
0
0
Total
15
180
6
9
0
0
45
60
30
15
15
180
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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Pre-rad Breakdown Voltage
Breakdown V (from IV) - comparing zones
1200
1000
V
800
Specs
>600V
600
Baseline
(common narrow p-stop)
Shows good behavior
400
200
BUT: no punch-through protection
0
Zone 4 has punch-through.
Zone 3 with p-spray is acceptable
Zone1, pspray
Zone3, pspray+pstop
Zone3, pstop
Zone4, pspray+pstop
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
Zone4, pstop
Zone5, pspray+pstop
Zone5, pstop
9
Pre-rad Isolation: Interstrip Resistance
Interstrip current
600
y = -312x + 223.49
R int = 2* DV2/Di1
1
10
75
100
500
1000
Linear (1)
Interstrip Resistance:
“no Bias Dependence”
100’s of GW
less for Zone 1 & 5?
i1 [pA]
400
300
200
100
0
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
V2 [V]
Pre-rad Rint ATLAS07
1000
Bias resistor current
1000
y = 1.51E+03x + 2.91E-01
800
100
i2 [pA]
400
200
-0.6
-0.4
-0.2
0
-200 0
0.2
0.4
0.6
Z1
Z1
Z3
Z3
Z4
Z4
Z5
Z6
Rint [Gohm]
600
10
-400
-600
p-spray
p-spray2
p-spray
p-stop
p-spray
p-stop
p-spray
p-spray
W02-BZ1-P7
-800
-1000
V2 [V]
1
0
100
200
300
400
500
Vbias
600
RBias = 1.22 MW
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700
800
900
10
1000
Pre-rad Isolation: Interstrip Capacitance
2.5
)Z3, p-spray (1MHz
)Z3, p-spray (2MHz
)Z1, p-spray (1MHz
)Z1, p-spray (2MHz
2
Cint [pF]
1.5
1
0.5
0
0
100
200
300
400
Bias [-V]
500
600
700
Interstrip capacitance to next neighbor pair (total ~30% higher):
Close to 1 pF/cm.
Same value for p-spray with and without implants
“No” bias dependence for Zone 1 and Zone 3
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Pre-rad Full-size Sensors (p-spray) : i-V
1.E-03
Leakage Current [A]
1.E-04
1.E-05
1.E-06
1.E-07
W14
W15
W16
W20
W21
W22
1.E-08
1.E-09
0
100
200
300
400
500
Bias [-V]
600
700
800
900
Average current before breakdown i(400V) = 0.83 uA = 8 nA/cm^2
Average breakdown: 530V
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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Full wafer (W9) strip test
• All four segments (of
all wafers) probed
• found less faulty
channels than
indicated by HPK (?)
• Testing (& retesting)
15360 channels takes
quite some time
(Brad Hommels, Cambridge)
SUNY Story Brook is working on this
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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i-V post KEK Protons & Ljubljana Neutrons
W13-BZ4-P4
Neutron 1E15
W26-BZ5-P11
Proton 1.32E15
1
1
0.1
0
200
400
600
800
1000
1200
0.1
200
400
600
800
1000
1200
0.01
0.01
0.001
0.001
0.0001
Current
0.0001
Current
0
1E-05
Irradiated
Unirradiated
1E-06
1E-05
1E-06
Irradiated
Unirradiated
1E-07
1E-07
1E-08
1E-08
1E-09
1E-09
1E-10
1E-11
1E-10
Voltage
Voltage
Post-rad no breakdown, in contrast to pre-rad
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Charge Collection KEK Proton Irradiation
W27-BZ3-P3 1.32e15 neq Proton
3
600
2.5
Med Q [fC]
2
400
1.5
300
1
200
MedQ
ToT @ 1fC
0.5
0
0
200
400
600
800
1000
100
0
1200
Bias [-V]
Collected Charge up to ~ 1000V
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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ToT @ 1fC [ns]
500
Efficiency post KEK Proton Irradiation
W27-BZ3-P3 1.32e15 neq Proton
1
0.9
0.8
Eff @ 1fC
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0
200
400
600
800
1000
1200
Bias [-V]
Efficiency @ 1fC Threshold saturates at ~ 600V
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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Charge Collection post KEK Proton Irradiation:
Affolder et al (Liverpool) ,
Compares well will Micron p and n irradiations
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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Surface: Gamma Irradiation at BNL:
Gamma Irradiation (1 Mrad, biased + 0.5V on Al) at BNL:
check Isolation, Interstrip Capacitance, MD
p-stop, zone 3
W26-BZ3-P13
p-stop, zone 4
W29-BZ4-P4
p-spray, zone1
W02-BZ1-P7
p-spray, zone3
W06-BZ3-P6
p-spray, zone4
W06-BZ4-P22
All Al readout traces are bonded out together
During irradiation bias the metal strips to +0.5 V
wrt to bias ring. Bias back plane to 200V.
RT annealing for about 10 days.
Take i-V with the Al either “grounded” or
“floating”
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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i-V post Gamma Irradiation
W26-BZ3-P13 1 Mrad Gamma Irradiated IV
5.E-06
3-17 pre-rad no bond
Leakage Current (A)
4.E-06
4-8 pre-rad bonded grounded
4-10 pre-rad bonded floating
6-24 floating
3.E-06
6-24 grounded
7-2 grounded
2.E-06
7-7 grounded
8.6 20 deg nitro flow floating
1.E-06
0.E+00
0
200
400
600
Bias Voltage (V)
800
1000
1200
Breakdown Behavior not fully understood
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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i-V post Gamma Irradiation:
W06-BZ4-P22 1 MRad Gamma Irradiated IV
Leakage Current (A)
5.E-06
4.E-06
3.E-06
3-12 pre-rad no bonding
4-8 pre-rad bonded strips grounded
4-10 pre-rad bonded floating strips
6-24 floating
2.E-06
6-24 grounded
1.E-06
7-2 grounded
0.E+00
7-2 floating
8-10 floating with nitro taken by hand
0
200
400
600
Bias Voltage (V)
800
1000
1200
N2 flow prevents breakdown
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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Isolation post Gamma Irradiation
Rint W06-BZ4-P22 P-spray
1.E+06
Rint (MOhm)
1.E+05
1.E+04
Pre-rad
1 MRad
1.E+03
1 Mrad N2 Flow!
1.E+02
1.E+01
0
100
200
300
400
Vbias
Interstrip Resistance much reduced, ok ?
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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Gamma Irradiation / Glue tests on-going
Observations after Irradiation with gamma’s and gluing to surface:
Breakdown voltage much reduced ( to 100-200V)
Improvement observed after cleaning and/or flushing with N2 gas
Short term annealing (~10 min @ 60 deg) does not help
Things to test:
origin of breakdown
effect of passivation
effect of guard rings
effect of accumulated surface charge
Comparison with other manufacturers helps
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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Summary ATLAS07
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n-in-p p-type microstrip sensors have been fabricated in p-FZ and p-MCZ wafers,
for several years by now at HPK.
Latest submission, ATLAS07, within the ATLAS R&D collaboration of
"Development of non-inverting Silicon strip detectors for the ATLAS ID upgrade"
Number of isolation structures are being investigated in mini-SSD test structures
A full size microstrip sensor has been prototyped for module/stave work.
Pre-series of ~9 wafers with many test structures received
Total of 132 wafers contracted, 2 different FZ wafer types
Full testing by HPK
Modification of masks required after first pre-series
HPK will investigate optimization of p-spray
Proton irradiations, 70 MeV, 800 MeV, 24GeV, neutron irradiations (1 MeV) and
gamma irradiation have been performed on the test structures
Good charge collection and low noise after hadron irradiations to 1e15
confirmed by several groups: bulk as expected
Apparent sensitivity to moisture can be overcome with N2 flow, more testing
needed
Program to investigate top-side gluing in full swing.
Concentrate on surface properties
US ATLAS Upgrade Strip Meeting, Hartmut F.-W. Sadrozinski, SCIPP
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