Download - SIPMs: Italy Team Report
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SIPMs: Italy Team Report
SiPMs development at FBK-irst started in 2005 as collaboration with INFN(*) for: - tracking with sci-fi; - PET; - TOF; - calorimetry; - muon counters.(*) Pisa, Bari, Bologna, Messina, Perugia, Roma, Trento,Trieste, Udine
INFN
Aldo Penzo, INFN-TriesteHCAL Working group, CMS Upgrade Workshop
FNAL, 19 Nov 2008
Trieste
Ljublijana
Legnaro
Trento Udine
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Summary of multiple contributions
• http://www.ts.infn.it/eventi/TPDPPC_2008/
• Valter Bonvicini - The INFN R&D FACTOR • Claudio Piemonte - Development of SiPMs at FBK-irst • Arjan Heering - Requirements of SiPMs for CMS HCAL upgrades • Adam Para - Photodectors for dual readout calorimetry:
characterization and testing of SiPMT's • Aldo Penzo - Calorimetry R&D in FACTOR• Dalla Torre - Single photon detectors for Cherenkov Imaging • Valter Bonvicini - Preliminary results on SiPM irradiation tests• Giovanni Pauletta - SiPM characterization and applications; past
and future test activities at FNAL
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FACTOR Project
• Within FBK/irst - INFN agreement, a (3-year) project (FACTOR) aims at establishing SiPMs as choice devices for (dual) readout of (compensating) hadron calorimeters.
• FBK-IRST has long-standing collaboration with INFN in the fields of:
– Radiation-hard Si detectors (for SLHC)– use of oxigen-rich substrates:
• DOFZ substrates• Cz/MCz substrates (Magnetic Czochralski)• Epitaxial substrates
– use of p-type substrates
– Integration of Si detectors and (front-end) circuits on the same substrate
– 3D detectors
[Walter Bonvicini et al.: Messina, Roma, Trieste, Udine + FBK/irst]
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ITC-IRST (Trento)ITC (Now Fondazione Bruno Kessler ) – IRST is a public research and technology Institute, working since 1994 on the development and on the production od semiconductor devices for research and applications. It has a fully equipped Microfabrication Laboratory in which silicon devices are built.
- Ion Implanter- Furnaces- Litho (Mask Aligner )- Dry&Wet Etching- Sputtering &Evaporator- On line inspection- Dicing
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Activity of SRD group
Development and production of Si radiation detectors.
Expertise covers the main aspects of the development:
TCAD simulationCAD design
Fabrication Device testing
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Previous/current products
• Double-sided strip detectors:– Area:7.5x4.2cm2 – Orthogonal or inclined strips on 2 sides– DC- or AC-coupled– 700 + 800 “in spec” devices fabricated for AMS
and ALICE (2002-2005)
• Pixel detectors: – MEDIPIX (thick 1.5mm), 170x170/55x55 m2
– ALICE (200m) 400x50 m2
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3D Si Detectors
See S. Parker et al., NIM A395 (1997)
Short distance electrodes n e p: low depletion voltage short charge collection distance
column type ncolumn type p
Wafer surface
Substrate type n
extremely fast and radiation resistant
Ionising track
electroelectro
nsns
hole
hole ss
(carriers generated along the track are collected almost simoultaneously)
Electrodes are columns penetrating into the bulk
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3D Si Detector Project
FBK-irst and INFN-Trieste (L. Bosisio et al.)
• Collaboration for tests:– Ljubljana– UC Santa Cruz – INFN-Genova (ATLAS Pixel) – CERN (ALICE Pixel)
• Applications of this technology in other devices:– ‘throughout holes” transfer signals to back face (ex.SiPM) – planar detectors with “active edge’ (ex. imaging X-rays)
n+ diffusion
contact
metal
oxidehole
SEM pictures of 3D devices
Col. depth 180mCol. width 10m
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SiPM IRST technology
• Substrate: p-type epitaxial• 2) Very thin n+ layer • 3) Polysilicon quenching resistance• 4) Anti-reflective coating optimized for ~420nm
13
14
15
16
17
18
19
20
0 0.2 0.4 0.6 0.8 1 1.2 1.4
depth (um)
Do
pin
g c
on
c. (
10
^)
[1/c
m^
3]
0E+00
1E+05
2E+05
3E+05
4E+05
5E+05
6E+05
7E+05
E f
ield
(V
/cm
)
Doping
Field
n+ pShallow-Junction SiPM
p+ subst.
epi
n+
Drift regionHigh field region
p
guard region
[C. Piemonte:“A new Silicon Photomultiplier structure for blue light detection” NIMA 568 (2006) 224-232]
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Configuration on Si wafer
First production run (2005) • square SiPMs with area: - 1x1mm2,2x2mm2
- 3x3mm2, 4x4mm2
- circular SiPMs- linear arrays of SiPMs: - 1x8, 1x16, 1x32- 4x4 matrix of SiPMs
Main blockWaferSecond production run
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Characteristics of FBK-irst SiPMs
Fill factor: 40x40m2 => ~ 40% 50x50m2 => ~ 50% 100x100m2 => ~ 76%
1x1mm2 2x2mm2 3x3mm2 (3600 cells) 4x4mm2 (6400 cells)
Geometries:
Circular: diameter 1.2mm diameter 2.8mm
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Tests performed at FBKTests performed at FBK
• I-V measurement
– fast test to verify functionality and uniformity of the properties
• Functional characterization in dark
– for a complete characterization of the output signal and noise properties (signal shape, gain, dark count, optical cross-talk, after-pulse)
• Photo-detection efficiency
C. Piemonte et al. “Characterization of the first prototypes of SiPM fabricated at ITC-irst” IEEE TNS, February 2007
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Leakage current: mainly due to surface generation at the micro-diode periphery
Static characteristic (I-V)Static characteristic (I-V)
Matrix 4x4 1-9
1.E-11
1.E-10
1.E-09
1.E-08
1.E-07
1.E-06
1.E-05
0 5 10 15 20 25 30 35Vrev [V]
I [A
]
SiPM4 - W12
Breakdown voltage
Breakdown current: determined by dark events
Very useful fast test. Gives info about:- Device functionality- Breakdown voltage- (Dark rate)x(Gain) uniformity- Quenching resistance (from forward I-V)
Reverse I-V
Performed on several thousands ofdevices at wafer level
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Dark signals are exactly equal to photo-generated signals functional measurements in dark give a complete picture of the SiPM functioning
Signal properties – NO amplifierSignal properties – NO amplifier
0.E+00
1.E-03
2.E-03
3.E-03
4.E-03
5.E-03
6.E-03
7.E-03
0.0E+00 1.0E-07 2.0E-07 3.0E-07 4.0E-07
Time (s)
Am
pli
tud
e (V
)
Thanks to the large gain it is possible to connect the SiPM directly to the scope
VBIAS
SiPM
50
DigitalScope
SiPM: 1x1mm2
Cell: 50x50m2
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15
0
100
200
300
400
500
600
700
800
0 20 40 60 80 100 120Charge (a.u.)
Co
un
ts
0.0E+00
5.0E+05
1.0E+06
1.5E+06
2.0E+06
2.5E+06
3.0E+06
3.5E+06
31 32 33 34 35 36
Bias voltage (V)
Ga
in
Pulse gen.
Laser
Pulse area= charge
histogram collection
SiPM
~ns
1p.e. 23
4
pedestal.
Excellent cell uniformity
Lineargain
Signal properties – NO amplifierSignal properties – NO amplifier
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s = singled = double pulsesa = after-pulse
VBIAS
SiPM
50
DigitalScope
Pulses at the scope.
Av100x
Signal properties – with amplifierSignal properties – with amplifier
A voltage amplifier allows an easier characterization,but attention must be paid when determining the gain
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Microcell functionality measurementsMicrocell functionality measurements
measurements with RWTH, Aachen and Josef Stefan , Ljublijana
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Pencil LED scan
Measurement of the microcells with 5m
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Uniformity map
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4x4mm2
0.01
0.10
1.00
10.00
-1.0E-08 5.0E-08 1.1E-07 1.7E-07 2.3E-07Time (s)
Am
plit
ud
e (
a.u
.)
1mm2
T = -15C
T = -25C
Signal shape
1mm2 SiPM
0.E+00
1.E+06
2.E+06
3.E+06
4.E+06
5.E+06
6.E+06
7.E+06
28 29 30 31 32 33
Voltage (V)
Da
rk c
ou
nt (
Hz)
16 x Dark Count of 1mm2 SiPM
-15C -25C
0.E+00
1.E+06
2.E+06
3.E+06
28 29 30 31 32 33
Voltage (V)
Ga
in
-15C
-25CGain
Dark count
4x4mm2 SiPM - 50x50m2 cell
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4x4mm2 SiPM - 50x50m2 cell
Same conclusions as for the previous device:
• Excellent cell response uniformity over the entire device (6400 cells) Width of peaks dominated by electronic noise
-5.E-10 2.E-09 4.E-09 6.E-09 8.E-09
Charge (V ns)
28.6V
29.2V
29.6V
12 3
4
5
1
2
34 5 6
12
3
4 5 6 7
8
T=-25C Vbd=27.6VCharge spectra when illuminating the device with short light pulses
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1.0E+02
1.0E+03
1.0E+04
1.0E+05
1.0E+06
-0.70 -0.60 -0.50 -0.40 -0.30 -0.20 -0.10 0.00
Threshold (V)
Cou
nts
DC 28DC 28.5DC 29DC 29.5DC 30DC 30.5DC 31DC 32DC 33
• Each of the above curves represents the dark count rate as a function of the counting discriminator threshold.
• Different curves correspond to different bias voltages. Dark counts were also measured as a function of temperature.
Dark counts vs discrim. threshold
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Photo-detection efficiency
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30
40
50
60
70
80
90
100
300 400 500 600 700 800Wavelength (nm)
QE
(%
)
0V
-2V
Simul
Simul ARC
0.00E+00
2.00E+00
4.00E+00
6.00E+00
8.00E+00
1.00E+01
1.20E+01
1.40E+01
1.60E+01
350 400 450 500 550 600 650 700 750 800
Wavelength (nm)
PD
E (
%)
36V
36.5V
37V
37.5V
38V
V=2V
2.5V
3.5V
3V
4V
QE vs Wavelength
long : low PDE becauselow QE
short : low PDE becauseavalanche triggered byholes
Measured on a diode
Reduced bysmall epi thickness
Reduced by ARC
Area efficiency ~ 20%
PDE=QE*Pt*Ae
QE=quantum eff.Pt=avalanche prob.Ae=area eff.
PD
E
350 400 450 500 550 600 650 700 750 800
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Comparison of PDE
• From Arjan in Trieste, 3 June 2008
PDE at ~3 volt overvoltage
-5
0
5
10
15
20
25
30
35
300 350 400 450 500 550 600 650 700 750 800
Wavelength
(%)
FBK 5(Ti,34 V)
FBK 11(AU,35 V)
Ham (3x3mm,70V)
CPTA (2.1x2.1mm 36V)
CPTA (3x3mm 22V)
HB,HE,HO
HF
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Activities at Trieste-Udine• The FACTOR collaboration is interested in the development of the
device and in its optimization for application to:
• Present application interests:– Calorimetry with fiber-based optical readout– Large – area scintillator – based muon counters– Scintillating fiber – based tracking– future space experiments for detection of UHECR– FEL studies and instrumentation– future large – area, ground – based x-ray telescopes
• Action Plan:– comparative studies for detailed understanding of device characteristics– Application tests– Optimization of properties as a function of application
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First year FACTOR • 2007: mainly dedicated to device characterization and test:
• Comparison of SiPM characteristics produced by different manufacturers;• Measurements of SiPM characteristics as a function of T;• Irradiation of the devices and study of radiation damage effects;• Tests with SiPMs coupled to wls fibers for scintillator read-out.• Energy and time resolution measurements;• Study of optimal packaging, electronics placement, etc.• At the moment, we are performing tests on SiPMs from 3 different• sources:• Forimtech (MRS):
– 1 mm2 in TO18 - P 560 nm - 556 µcells 43x43 µm2• Photonique (MRS):
– “GR sensitive” - 1 mm2 in TO18 - 556 µcells ~ 43x43 µm2– “Blue sensitive” - 1 mm2 in TO18 - 556 µcells ~ 43x43 µm2– “Blue sensitive” - 4.4 mm2 on PCB - 1748 µcells ~ 50x50 µm2– “Blue enhanced” – 9 mm2 in TO5 – 8100 µcells ~ 33x33 µm2
• IRST (polysilicon), 1 mm2 - P 420 nm (devices from 2nd and 3rd batch)– 625 µcells, 40x40 µm2
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Fast Amplifier• Amplifier used for fast
characterization of SiPMs:• Agilent ABA-52563 3.5 GHz RFIC
Amplifier• (economic, compact, internally
50-Ω matched, gain ~ 20 dB)
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Amplifier Characterization
• Temperature dependence:• Measurements performed with
the DUT in a climatic chamber (with humidity control)
• The amplifier was outside the chamber, connected via a special 18 GHz ft 50 cable.
• Timing characteristics can be studied
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Test Setup at INFN Lab
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Present Tasks • SiPM Development
– Comparative device characterization (ISRT, Hamamatsu, Formitech)
– Development (in collaboration with IRST)– Optimization of packaging & (fast!) preamplification
• Irradiation studies (so far on 24 SiPM's) – FBK-irst, Hamamatsu Photonique, Formitech– X-rays @ INFN Legnaro Labs (50 – 500 krad)– neutrons @ IJS reactor, Ljubljana (~4.8 x 101 0 n/cm 2 )
• Application Studies– Large area muon counters (FNAL)– Calorimetry with optical readout (FNAL/CERN/Frascati)– Scintillator-based fine-grained hodoscopes (CERN)
• Preliminary study of Scint. Strips viewed by IRST SiPM at the FNAL test beam (prototype of muon detector/tail catcher for ILC)
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Test at Frascati
Electron beam with a Cherenkov calorimeter counting multiplicity
6 cm
6 cm
2.5 cm
Scint. TileSiPM
WLS fiber
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Test beam at CERN
• Test beam at CERN (May/June 2008) with the MICE experiment: 8 extruded scintillator bars (1.5x1.9x19 cm3) with wls fibers, read out by SiPMs (IRST and Hamamatsu), all other bars of the MICE calorimeter read out by MAPMT.
• An ad hoc mechanical receptacle was realized to couple and align the fibers with the SiPMs and test them in a 2 GeV positron beam
• Frontend electronics: VA64TAP3.1 +LS64 by Gamma Medica-IDEAS; trigger signals sampled by an Altera with a 320 MHz clock
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Mice detector
• A small fraction of the prototype fibers are readout with SiPM. The SiPM receptacle is visible to the right
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The SiPM response
• Correlation MAPMT vs SiPM amplitude
Pulse-height plot of the SiPM obtained selecting good events on the MAPM side
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Radiation studies• Systematic campaign this year: study resistance to radiation
effects of SiPMs produced by different manufacturers– Objective: study both surface and bulk damage in the devices– Types of radiation used: X-rays (up to 50 keV) and neutrons– Measurement strategy: I-V characterization, dark count and gain
before and after irradiations, annealing studies– 24 devices from FBK-irst, Photonique (CPTA) and Hamamatsu
irradiated so far; further irradiations are foreseen in the next weeks
• X-rays: INFN National Laboratories of Legnaro (LNL), X-ray tube (W target), Vmax = 50 kV, dose rate measured with calibrated Si p-i-n diodes
• Neutrons: Nuclear Reactor of the Institute Josef Stefan of Ljubljana (Slo), max power ~ 250 kW, very high fluence achievable
X-rays @ INFN Legnaro Labs (50, 100 and 150 krad); X-rays @ INFN Legnaro Labs (300 and 500 krad); neutrons @ IJS reactor, Ljubljana (fluence ~ 4.8 x 1010 n/cm-2);
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Irradiation studies (so far on 24 SiPM's) – X-rays @ INFN Legnaro Labs (50 – 500 krad)– neutrons @ IJS reactor, Ljubljana (~4.8 x 1010 n/cm2)– (spectrum ?)
– Very preliminarly:
– With 300 krad X-rays, HPK DC increase by 20 – 25– FBK by 4 - 5 – With 500 krad, HPK by 36-40, FBK by 6 - 8
– With 4.8 x 1010 n/cm2, HPK DC increase by 45-60, FBK by 15 - 20 . (See next page)
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Other measurements and estimates
See: T. Matsumura (June 29, 2007) International Workshop on new photon-detectors (PD07)(Kobe University)
Neutron ≈ Proton
Proton ≈ 100 x X-ray
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Triga 3 reactor JSL
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Magnetic field resistance
• “Investigation of a Solid-state Photodetector”, NIM A 545:727-737 (2005).
• “Effects of a strong magnetic field on LED, extruded scintillator and MRS photodiode”, NIM A553: 438-447 (2005)
• (Vishnu V. Zutshi)
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SiPM for HF?• PMT fake signals in HF: show-stopper?
• SiPM useful but:
• Radiation hard?
• Small dimensions?
• Dinamic range?
• Consider matrix of 4x4 mm2 FBK SiPM– To cover 2.4 cm diameter PMT window
~130 GeV
up to few TeV!
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SiPM matrix…
…if 1 SiPM costs ≤10$ …
… not out of question?