Status of the Micro Vertex Detector M. Deveaux, Goethe University Frankfurt for the CBM-MVD...
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Transcript of Status of the Micro Vertex Detector M. Deveaux, Goethe University Frankfurt for the CBM-MVD...
Status of the Micro Vertex Detector
M. Deveaux, Goethe University Frankfurt for the CBM-MVD collaboration
The CBM-MVD
M. Deveaux 2
CB
M
We are here
How will it look
M. Deveaux 3
Magnet Silicon Tracking System
DAQcards
Vacuum vessel
MVD - planes
4M. Deveaux,
Open charm reconstruction: Concept
Primary Beam: 25 AGeV Au Ions (up to 109/s)
Primaryvertex Secondary
vertex
Short lived particle D0 (ct = ~ 120 µm)
Detector 1Detector2Target
(Gold)
z
Reconstruction concept for open charm
Central Au + Au collision (25 AGeV)
• A good time resolution to distinguish the individual collisions (few 10 µs)
• Very good radiation tolerance (>1013 neq/cm²)
Reconstructing open charm requires: • Excellent secondary vertex resolution (~ 50 µm)=> Excellent spatial resolution (~5 µm)=> Very low material budget (few 0.1 % X0)=> Eventually: Detectors in vacuum
5
Status of the sensors (last meeting 2011)
M. Deveaux
CBMSIS300
MAPS*(2003)
MAPS* (2011)
MIMOSA-26
(2010)
Single point res. ~ 5 µm 1.5 µm 1 µm 4 µm
Material budget < 0.3% X0 ~ 0.1% X0 ~ 0.05% X0 ~ 0.05% X0
Rad. hard. non-io. >1013 neq 1012 neq/cm² 1x1013 neq 1013 neq
Rad. hard. io > 3 Mrad 200 krad > 1 Mrad > 500 krad
Time resolution < 30 µs ~ 1 ms ~ 25 µs 110 µs
Optimized for one parameter Current compromise
Monolithic Active Pixel Sensors(MAPS, also CMOS-Sensors)
• Invented by industry (digital camera)• Modified for charged particle detection
since 1999 by IPHC Strasbourg • Also foreseen for ILC, STAR, ALICE…
=> Sharing of R&D costs.
A word on simulation
6M. Deveaux
MVD and STS
integration
Global design: How many MVD stations?
M. Deveaux 7
5 cm
Targ
et
MV
D 1
MV
D 2
ST
S 1
ST
S 2
ST
S 3
Vacuumwindow
Tracking, artist view
Global design: How many MVD stations?
M. Deveaux 8
5 cm
Targ
et
MV
D 1
MV
D 2
ST
S 1
ST
S 2
ST
S 3
Vacuumwindow
Tracking, artist view
Global design: How many MVD stations?
M. Deveaux 9
5 cm
Targ
et
MV
D 1
MV
D 2
ST
S 1
ST
S 2
ST
S 3
Vacuumwindow
Tracking, artist view
Global design: How many MVD stations?
M. Deveaux 10
5 cm
Targ
et
MV
D 1
MV
D 2
ST
S 1
ST
S 2
ST
S 3
Vacuumwindow
Tracking, artist view
Global design: How many MVD stations?
M. Deveaux 11
5 cm
Targ
et
MV
D 1
MV
D 2
ST
S 1
ST
S 2
ST
S 3
Vacuumwindow
Tracking, artist view
Global design: How many MVD stations?
M. Deveaux 12
5 cm
Targ
et
MV
D 1
MV
D 2
ST
S 1
ST
S 2
ST
S 3
Vacuumwindow
Tracking, artist view
L1 “MVD track finding efficiency” vs. MVD design
13
MV
D tr
ack
findi
ng e
ffici
ency
[%]
2 MVD stations
3 MVD stations
4 MVD stations
5 10None pile up
100% = primary tracks, geo-metrically accepted by MVD,> 4 hits in STS
90
50
Tracking efficiency = 83% for standard MVD, drops to <55% at pile up 10
Tracking efficiency is substantially improved by additional stations
Impact for 4th station to be studied in detail
M. Deveaux
C. T
rageser
Background rejection capabilities of the MVD
14
0
50
None 5 10
acce
pted
BG
-tra
cks
/ eve
nt
Bad reconstruction
Some bad hits
Good track finding
Not accepted
Cuts:p >1 GeVpt>0.3 GeVLong (>4 in STS)IP<600µmIP/sIP>6
M. Deveaux
More than 2 MVD stations are needed for BG rejectionExpect good sensitivity for open charm with >3 stations
C. T
rageser
Sensor R&D
M. Deveaux 15
for (Int_t Mimosa=1; true; Mimosa++) {
Build_Next_Prototype (Mimosa);Test_Prototype (Mimosa);Enjoy_Spectacular_Progress_Of(Mimosa);
ImproveDesign(Mimosa);}
0 5 10 15 20 25 30 35 401011
1012
1013
1014
1015
MIMOSA-9
MIMOSA-9
MIMOSA-15 (2006)MIMOSA-18 (2008)
Uncertainty range
Radia
tion tole
rance
[n
eq/c
m²]
Pixel pitch [µm]
Long standing believes vs. technological progress
16
A small pixel pitch is needed to reach the radiation tolerance needed for CBM
CBM goal
M. Deveaux
17M. Deveaux
Sensor R&D: The operation principle
Reset+3.3V+3.3V
Output
SiO2 SiO2 SiO2
N++ N++N+ P+
P-
P+
15µm50µm
18
Sensor R&D: Tolerance to non-ionising radiation
+3.3VOutput
SiO2 SiO2
N++
N+SiO2 SiO2
P++ P++ P++
GND GND
+3.3V
19
Sensor R&D: Tolerance to non-ionising radiation
+3.3VOutput
SiO2 SiO2
N++
N+SiO2 SiO2
P++ P++ P++
GND GND
+3.3V
Key observation: Signal amplitude is reduced by bulk damage
20
Sensor R&D: Tolerance to non-ionising radiation
+3.3VOutput
SiO2 SiO2
N++
N+SiO2 SiO2
P++ P++ P++
GND GND
+3.3V
Electric field increases the radiation hardness of the sensorDraw back: Need CMOS-processes with low doping epitaxial layer
E
Long standing believes vs. technological progress
21
A small pixel pitch is needed to reach the radiation tolerance needed for CBM
MIMOSA-32:20x40µm² pixel99.5%0 5 10 15 20 25 30 35 40
1011
1012
1013
1014
1015
MIMOSA-9
MIMOSA-9
MIMOSA-15 (2006)MIMOSA-18 (2008)
MIM
OSA-18 AHR (2011)*
Sensor based on high-resistivity EPI layer Sensor based on low-resistivity EPI layer Uncertainty range
Ra
dia
tion
to
lera
nce
[n
eq/c
m²]
Pixel pitch [µm]* Cooled down to -35°C
D. Doering et al. – Mimosa18 AHR
CBM goal
M. Deveaux
22
Status of the sensors (last meeting 2011)
M. Deveaux
CBMSIS300
MAPS*(2003)
MAPS* (2011)
MIMOSA-26
Binary, 0
Single point res. ~ 5 µm 1.5 µm 1 µm 4 µm
Material budget < 0.3% X0 ~ 0.1% X0 ~ 0.05% X0 ~ 0.05% X0
Rad. hard. non-io. >1013 neq 1012 neq/cm² >1x1013 neq >1013 neq
Rad. hard. io > 3 Mrad 200 krad > 1 Mrad > 500 krad
Time resolution < 30 µs ~ 1 ms ~ 25 µs 110 µs
Optimized for one parameter Current compromise
Monolithic Active Pixel Sensors(MAPS, also CMOS-Sensors)
• Invented by industry (digital camera)• Modified for charged particle detection
since 1999 by IPHC Strasbourg • Also foreseen for ILC, STAR, ALICE…
=> Sharing of R&D costs.
23
Update on sensor R&D
M. Deveaux
CBMSIS300
MAPS*(2003)
MAPS* (2013)
MIMOSA-26
Binary, 0
Single point res. ~ 5 µm 1.5 µm 1 µm 4 µm
Material budget < 0.3% X0 ~ 0.1% X0 ~ 0.05% X0 ~ 0.05% X0
Rad. hard. non-io. >1013 neq 1012 neq/cm² >3x1014 neq >1013 neq
Rad. hard. io > 3 Mrad 200 krad > 1 Mrad > 500 krad
Time resolution < 30 µs ~ 1 ms ~ 25 µs 110 µs
Optimized for one parameter Current compromise
Monolithic Active Pixel Sensors(MAPS, also CMOS-Sensors)
• Invented by industry (digital camera)• Modified for charged particle detection
since 1999 by IPHC Strasbourg • Also foreseen for ILC, STAR, ALICE…
=> Sharing of R&D costs.
Challenge: Find MAPS-compatible 0.18µm CMOS process
• 32 mm² surface
Radiation tolerance of MAPS
24
So far - Radiation tolerance limited by:
• Leakage current – noise• Conduction channels between transistors (?)
DONE
First prototype: MIMOSA-32
• 32 different kinds of pixels• 32 µs readout time
33 mm²
Known solution: • Use 0.18 µm CMOS instead of 0.35µm CMOS
M. Deveaux
Long standing believes vs. technological progress
25
A small pixel pitch is needed to reach the radiation tolerance needed for CBM
MIMOSA-32:20x40µm² pixel99.5%0 5 10 15 20 25 30 35 40
1011
1012
1013
1014
1015
MIMOSA-9
MIMOSA-9
MIMOSA-15 (2006)MIMOSA-18 (2008)
MIM
OSA-18 AHR (2011)*
Sensor based on high-resistivity EPI layer Sensor based on low-resistivity EPI layer Uncertainty range
Ra
dia
tion
to
lera
nce
[n
eq/c
m²]
Pixel pitch [µm]* Cooled down to -35°C
CBM goal
Mimosa-32, 20x40µm² pitch(Beam test @ SPS by IPHC, preliminary)
99.5% detection efficiencyAfter 1013 neq/cm² + 1 MRad !
M. Deveaux
Long standing believes vs. technological progress
26
MIMOSA-32:20x40µm² pixel99.5%0 5 10 15 20 25 30 35 40
1011
1012
1013
1014
1015
MIMOSA-9
MIMOSA-9
MIMOSA-15 (2006)MIMOSA-18 (2008)
MIM
OSA-18 AHR (2011)*
Sensor based on high-resistivity EPI layer Sensor based on low-resistivity EPI layer Uncertainty range
Ra
dia
tion
to
lera
nce
[n
eq/c
m²]
Pixel pitch [µm]* Cooled down to -35°C
CBM goal
Mimosa-32, 20x40µm² pitch(Beam test @ SPS by IPHC, preliminary)
99.5% detection efficiencyAfter 1013 neq/cm² + 1 MRad !
A small pixel pitch is needed to reach the radiation tolerance needed for CBM
M. Deveaux
Why is this important?
27
Pixel with pedestal correction
~1000 discriminators
On - chip cluster-finding processor
Output: Cluster information(zero suppressed)
50 µ
s/frame
25 µ
s/frame
12 µ
s/frame
~2000
20x20µm² 20x40µm²
Requires 0.18µm CMOSTest chip submitted
M. Deveaux
Why is this important
28
Pixel with pedestal correction
~1000 discriminators
On - chip cluster-finding processor
Output: Cluster information(zero suppressed)
50 µ
s/frame
25 µ
s/frame
12 µ
s/frame
~2000
20x20µm² 20x40µm²
Requires 0.18µm CMOSTest chip submitted
M. Deveaux
MAPS are too slow for CBM
Why is this important
29
There is a clear strategy for reaching the readout speed neededfor CBM
Pixel with pedestal correction
~1000 discriminators
On - chip cluster-finding processor
Output: Cluster information(zero suppressed)
50 µ
s/frame
25 µ
s/frame
12 µ
s/frame
~2000
20x20µm² 20x40µm²
Requires 0.18µm CMOSTest chip submitted
M. Deveaux
30
Update on sensor R&D
M. Deveaux
CBMSIS300
MAPS*(2003)
MAPS* (2013)
MIMOSA-26
Binary, 0
Single point res. ~ 5 µm 1.5 µm 1 µm 4 µm
Material budget < 0.3% X0 ~ 0.1% X0 ~ 0.05% X0 ~ 0.05% X0
Rad. hard. non-io. >1013 neq 1012 neq/cm² >3x1014 neq >1013 neq
Rad. hard. io > 3 Mrad 200 krad > 1 Mrad > 500 krad
Time resolution < 30 µs ~ 1 ms ~ 25 µs 110 µs
Optimized for one parameter Current compromise
Monolithic Active Pixel Sensors(MAPS, also CMOS-Sensors)
• Invented by industry (digital camera)• Modified for charged particle detection
since 1999 by IPHC Strasbourg • Also foreseen for ILC, STAR, ALICE…
=> Sharing of R&D costs.
MIMOSA-32 and ionizing radiation
M. Deveaux 31
0 1 2 3 4 5 6 7 8 9 100369
1215182124273033
EN
C [e]
Ionizing radiation dose [Mrad]
0.35µm 0.18µm
Noi
seSensor irradiated with X-rays @ CERN
Noise increases much slower (as expected)Higher initial noise (not expected)
D. D
oering
32
Sensor R&D: Tolerance to non-ionising radiation
+3.3VOutput
SiO2 SiO2
N++
N+SiO2 SiO2
P++ P++ P++
GND GND
+3.3V
Study noise with varied size of transistor gate
Comparison with 0.18µm vs. AMS 0.35
M. Deveaux 33
0 10 20 30 40 50 60 70 80 90 1001
10
100
Ent
ries
Noise [e]
Mi18AHR A2 Mi32ter P2 Std. Mi32ter P5 Tiny SF
Dennis Doering
D. D
oerin
g
0.35 µm, big 0.18µm, small
0.18µm, tiny
Going into details
34
0 10 20 30 40 50 60 70 80 90 1001
10
100
Ent
ries
Noise [e]
Mi18AHR A2 Mi32ter P2 Std. Mi32ter P5 Tiny SF
Dennis Doering
M. W
inter et al.
Random Telegraph Signal
35
M. W
inter et al.
RTS, illustration
Sensors see difference between two samples
Side peaks due to change of state.
Problem understood, => Need bigger gates
36
So what?
M. Deveaux
CBMSIS300
MAPS*(2003)
MAPS* (2013)
MIMOSA-26
Binary, 0
Single point res. ~ 5 µm 1.5 µm 1 µm 4 µm
Material budget < 0.3% X0 ~ 0.1% X0 ~ 0.05% X0 ~ 0.05% X0
Rad. hard. non-io. >1013 neq 1012 neq/cm² >3x1014 neq >1013 neq
Rad. hard. io > 3 Mrad 200 krad > 1 Mrad > 500 krad
Time resolution < 30 µs ~ 1 ms ~ 25 µs 110 µs
Optimized for one parameter Current compromise
Mimosa-32, 20x20µm² pitch(Beam test @ SPS by IPHC, preliminary)
99.5% det. efficiency (S/N ~30)After 3 MRad at +15°C!
37M. Deveaux
So what?
CBMSIS300
MAPS*(2003)
MAPS* (2013)
MIMOSA-26
Binary, 0
Single point res. ~ 5 µm 1.5 µm 1 µm 4 µm
Material budget < 0.3% X0 ~ 0.1% X0 ~ 0.05% X0 ~ 0.05% X0
Rad. hard. non-io. >1013 neq 1012 neq/cm² >3x1014 neq >1013 neq
Rad. hard. io > 3 Mrad 200 krad > 3 Mrad > 500 krad
Time resolution < 30 µs ~ 1 ms ~ 25 µs 110 µs
Optimized for one parameter Current compromise
Mimosa-32, 20x20µm² pitch(Beam test @ SPS by IPHC, preliminary)
99.5% det. efficiency (S/N ~30)After 3 MRad at +15°C!
Next steps in the R&D
38
Pixel with pedestal correction
~1000 discriminators
On - chip cluster-finding processor
Output: Cluster information(zero suppressed)
Prototype MIMOSA-22THRsubmitted
Already excellent butGet rid of RTS4 prototypes submitted
Prototype SUZE - 2submitted
First prototypes in 0.18µm CMOS show spectacular results.Full engineering run (11 CBM relevant prototypes) submitted.More to come => Stay tuned.
M. Deveaux
How to integrate the sensors?
M. Deveaux, CBM Collaboration Meeting, Kolkata, 24-28. Sept 2012 39
MIMOSA-26 (600 kPixel, 104 frames/s, zero suppression) Thinned to 50µm, at IKF Frankfurt
See next talk (M. Koziel)
Summary
40
Sensors for MVD (since 2010)
• Radiation tolerance (non-io.) was improved by factor 10• Radiation tolerance (io) was improved by factor > 3• All sensor requirements for CBM are individually demonstrated• Still room for improvement in 0.18µm process
• Ongoing effort to combine all functionalities
Simulation
• MVD needs 3 or 4 stations for good performance
Prototype and integration: Very promising (see next talk)
M. Deveaux, CBM Collaboration Meeting, Kolcata, 24-28. Sept 2012 41The prototype DAQ at night
PICSEL Group IPHC, Strasbourg (sensor R&D + test)Thanks to: S. Amar-Youcef, B. Milanovic, Q. Li (Prototype firmware and analysis) M. Koziel, T.Tischler (mechanical integration)B. Neumann (JTAG slow control), M. Wiebusch (analog electronics)C. Trageser (simulation)C. Schrader (DAQ concept and coordination, now with BOSCH),