=Paper=
{{Paper
|id=Vol-2507/418-422-paper-77
|storemode=property
|title=Radiation Damage Studies of Silicon Photomultipliers in Neutrons Field of IBR-2
|pdfUrl=https://ceur-ws.org/Vol-2507/418-422-paper-77.pdf
|volume=Vol-2507
|authors=Sergey Afanasiev,Yuriy Ershov,Igor Golutvin,Nikolay Gorbunov, Alexandr Malakhov,Vitaliy Smirnov,Nikolay Zamyatin,Evgeny Sukhov,Valentin Ustinov
}}
==Radiation Damage Studies of Silicon Photomultipliers in Neutrons Field of IBR-2==
https://ceur-ws.org/Vol-2507/418-422-paper-77.pdf
Proceedings of the 27th International Symposium Nuclear Electronics and Computing (NEC’2019)
Budva, Becici, Montenegro, September 30 – October 4, 2019
RADIATION DAMAGE STUDIES OF SILICON
PHOTOMULTIPLIERS IN NEUTRONS FIELD OF IBR-2
S.V. Afanasiev1,2, Yu.V. Ershov1, I.A. Golutvin1, N.V. Gorbunov1,2,
A.I. Malakhov1,2, V.A. Smirnov1,2, N.I. Zamyatin1 , E.V. Sukhov1,
V.V. Ustinov1,2
1
Joint Institute for Nuclear Research, Dubna, 141980, Russia
2
Dubna State University, Dubna, 141980, Russia
E-mail: a afanasev@lhe.jinr.ru, b suhov@junr.ru, c ustinov@jinr.ru
The report is devoted to the study of radiation resistance of silicon photomultipliers (SiPM) produced
by HAMAMATSU. SiPM was irradiated in neutron fluxes of the JINR IBR-2 reactor. The tested
SiPM received fluence from 1012 up to 2x1014 of neutrons/cm2. Irradiated detectors were investigated
using a radioactive source and laser flashes at a temperature of -30oC. The measurements showed that
the SiPM remain fully functional as photon detectors up to neutron fluence 2x1014 despite a significant
increase in noise.
Keywords: CMS, SiPMs, radiation hardness.
Sergey Afanasiev, Yuriy Ershov, Igor Golutvin, Nikolay Gorbunov, Alexandr Malakhov, Vitaliy
Smirnov, Nikolay Zamyatin, Evgeny Sukhov, Valentin Ustinov
Copyright © 2019 for this paper by its authors.
Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).
418
Proceedings of the 27th International Symposium Nuclear Electronics and Computing (NEC’2019)
Budva, Becici, Montenegro, September 30 – October 4, 2019
Introduction
A future replacement of the HE calorimeter for scintillator section of the CMS HL-LHC
endcap calorimeters during the LS3 period presupposes the installation of the photo detectors (SiPM)
directly on the scintillation tiles [1]. The radiation exposure of the calorimeter was estimated up to the
integral luminosity of 3000 fb-1 at HL-LHC. There were defined areas of the detector with different
levels of irradiation. A necessary condition for the modernization of the spectrometer is to ensure the
operability of active detector elements.
Silicon photomultipliers (SiPM) are a new type of photodetectors. They consist of miniature
diodes operating in streamer mode (APD). The detector has a high sensitivity and is able to register
individual photons On the one hand, SiPM is characterized by a low supply voltage and insensitivity
to the magnetic field, and on the other, by a high dependence of the gain on temperature and the
destruction of the detector structure in the strong radiation fields typical for modern spectrometers.
The work is devoted to the study of radiation effects on SiPM structures.
Irradiation of SiPMs with neutrons
JINR group performs the investigation of some SiPM properties after irradiating them with
neutrons at the IBR-2 reactor. The main goal of the work is to estimate the upper limit of neutron
irradiation, which will lead to the impossibility of further use of SiPM in the central region of the
scintillation part of CMS calorimeters cooled to -30 °C. The main criterion for the operation of SiPM
is the possibility of recording by a photo detector MIP signals above the noise level.
Irradiation of 21 SiPM photo detectors with fast neutrons was carried out in two runs at IBR-2
[2]. The first run was held in November 2016 and the second one - in March 2017. Three types of
Hamamatsu SiPM devices were used for irradiation with dimensions of 10, 15 and 25 μm cells: MPPC
S12571-010C [3], MPPC S12571-015C [3], MPPC S13360-1325CS [3]. Each SiPM has an
identification number which was used for the subsequent reference (Table 1).
Table 1. Identification numbers for the used SiPMs
MPPC S12571-010C 403, 404, 412, 413, 414, 415, 416
MPPC S12571-015C 184, 185, 188, 189, 190, 191, 192
MPPC S13360-1325CS 10327, 10328, 10355, 10356, 10357, 10358, 10359.
Three photo detectors, one of each type, were combined in a set. There were seven sets in tota.
SiPMs of each set received the same neutron radiation. The sets were irradiated in the range of fluence
values 1.7 × 1012 ÷ 2.1 × 1014 neutrons/cm2. Table 2 shows the magnitudes of neutron fluence and the
date of irradiation for each set of photo detectors.
Table 2. Magnitudes of neutron fluence and date of irradiation for each set of photodetectors
Set # Set composition Ф, neutrons/cm2 Date of irradiation
1 412, 188, 10355 1,7×1012 03.2017
2 413, 189, 10356 5,3×1012 03.2017
3 403, 184, 10328 5,4×1012 11.2016
4 414, 190, 10357 1,7×1013 03.2017
5 415, 191, 10358 5,18×1013 03.2017
6 416, 192, 10359 8,14×1013 03.2017
7 404, 185, 10327 2,1×1014 11.2016
The magnitude of neutron fluence was measured by two methods:
The first method was standard and used at IBR-2. The technique was based on
measuring the induced activity of Nickel wires irradiated together with the samples.
The second method was based on the measurement of the quantity of defects in two
silicon semiconductor detectors located near each set of SiPM devices.
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Proceedings of the 27th International Symposium Nuclear Electronics and Computing (NEC’2019)
Budva, Becici, Montenegro, September 30 – October 4, 2019
Measurement of main parameters of the SiPM
All photodetectors passed test procedures to measure the main parameters after irradiation and
to compare them with parameters defined in factory specifications. Table 3 presents the main
parameters of the investigated devices.
Table 3. The main parameters of SiPM before and after irradiation
S12571-010С, area - 1mm2, 10 000 of 10 μm cells
Before irradiation (spec. HPK), After irradiation,
-2 SiPM at +25° Measurement at -22°
Ф, cm
number Fdark, kHz, Vbr,V Vbr,V σnoise, pixels Fdark, kHz
Vop,V M (gain)
(0,5pix) (noise) (dI/dU/I) Vov=3V Vov=3V
1,7×1012 412 69,86 1,35×105 111 63.265 63.205 3.74 6530
5,3×1012 413 69,88 1,36×105 110 63.31 63.46 7.56 9080
5,4×1012 403 69,81 1,34×105 124 63.25 63.4 7.0 9040
1,7×1013 414 69,9 1,35×105 115 63.41 63.46 9.6 9985
5,18×1013 415 69,87 1,35×105 113 63.78 64.13 11.8 10530
8,14×1013 416 69,89 1,35×105 108 63.91 64.06 12.8 10610
2,1×1014 404 69,82 1,34×105 119 65.71 66.28 15.5 10710
S12571-015С, area - 1mm2, 4 489 of 15 μm cells
Before irradiation (spec. HPK), After irradiation,
-2 SiPM at +25° Measurement at -22°
Ф, сm
number Fdark, kHz, Vbr,V Vbr,V σnoise, pixels Fdark, kHz
Vop,V M (gain)
(0,5pix) (noise) (dI/dU/I) Vov=3V Vov=3V
1,7×1012 188 67,96 2,3×105 98,7 62.11 62.06 5.63 8040
5,3×1012 189 68,05 2,29×105 118 62.05 62.3 8.92 8640
5,4×1012 184 67,99 2,30×105 109 62.11 62.13 8.78 8517
1,7×1013 190 68,08 2,32×105 111 62.31 62.5 12.3 8749
5,18×1013 191 68,07 2,29×105 107 62.51 62.86 12.5 8840
8,14×1013 192 68,11 2,29×105 125 62.96 63.3 13.1 8798
2,1×1014 185 68,02 2,31×105 111 64.51 64.89 12.3 8989
S13360-1325СS, area - 1,69 mm2, 2 668 of 25 μm cells
Before irradiation,
After irradiation
+25°C and Vop = Vbr + 5V,
-22°C
SiPM
Ф, сm-2
number σnoise,
Vbr,V Vbr,V
Id, uA, Vbr, V pixels
(noise) (dI/dU/I)
Vov=3V
1,7×1012 10355 0,029 53,72 49.41 49.35 5.85
5,3×1012 10356 0,018 52,95 49.48 49.51 -
5,4×1012 10328 0,019 52,53 49.2 49.13 8.87
1,7×1013 10357 0,028 53,13 49.61 49.8 8.84
5,18×1013 10358 0,017 51,87 49.85 50.25 8.85
8,14×1013 10359 0,016 51,94 49.85 50.0 8.8
2,1×1014 10327 0,016 51,83 49.91 50.0 8.64
The parameters of unirradiated SiPMs were taken from the Hamamatsu data sheets. All the
values were specified for + 25 °C. For S12571-010C and S12571-015C amplification (M), operating
voltage (Vop) and dark noise frequency (Fdark) at the threshold of 0.5 pixels are given. The
breakdown voltage (Vbr) was not specified. The data sheet of S13360-1325SS specified the typical
dark current as 70 kHz and the typical gain as 7.0×105. There was indicated the breakdown voltage
(Vbr) and current of the detector (Id) for each device in the present paper.
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Proceedings of the 27th International Symposium Nuclear Electronics and Computing (NEC’2019)
Budva, Becici, Montenegro, September 30 – October 4, 2019
Measurement the signal to noise ratio for SiPMs
All SiPM photo detectors were examined before and after irradiation. For the measurement we
used a setup shown in Figure 1. The signal in the scintillator was excited by two sources:
The first one was a 90Sr radioactive source.
The second one is a laser whose signal was as from a particle with a minimum
ionizing capability (MIP).
The SiPM response was measured at room temperature and at -30 °C.
The results of measurements of SiPMs irradiated to a value of 5.38 × 10 12 neutrons/cm2 are
shown in Figure 2 for the light signal excited by a radioactive source. The results of laser
measurements of the same SiPM devices are shown in Figure 3. For a cooled photo detector the MIP
signal is almost 12 times higher than the noise level.
The results of measurements of SiPM devices irradiated to 2.09 × 1014 neutrons/cm2 for both
sources of light are shown in Figure 4. A photo detector was cooled up to -32 °C. Measurements at
room temperature were not carried out because the noise level from the photo detector was too high.
A registration of the MIP signal for SiPMs irradiated to 2.09 × 1014 neutrons/cm2 becomes
problematic due to a high noise level even at -32 °C. The signal-to-noise ratio is at the level of ~ 1.
Figure 1. Setup used for measurement of SiPM response
90Sr Test
Signal
T=+25 OC
S/N=1.08
Noise
Signal
T=-32OC
S/N=10
Noise
Figure 2. Results of measurements of SiPMs irradiated to a value of 5.38 × 1012 neutrons/cm2 using
90
Sr as source of light
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Proceedings of the 27th International Symposium Nuclear Electronics and Computing (NEC’2019)
Budva, Becici, Montenegro, September 30 – October 4, 2019
Laser Test
Signal ~14p.e.
T=+25 OC
S/N=1.8
Noise
Signal ~14p.e.
T=-32OC
S/N=11.8
Noise
Figure 3. Results of laser measurements of SiPMs irradiated to a value of 5.38×1012 neutrons/cm2
Figure 4. The results of measurements of SiPM devices irradiated to 2.09 × 1014 neutrons/cm2 for both
sources of light at -32 °С
Conclusion
JINR study shows that up to irradiation levels of ~ 5.4 × 1012 neutrons / cm2, the above-mentioned
Hamamatsu photodetectors will ensure the recording of signals from MIP particles in case of SiPM-
on-tile readout in the scintillator section of the CMS HL-LHC endcap calorimeters.
References
[1] J. Mans and P. de Barbaro. The baseline readout of the scintillator section of the CMS HL-LHC
Endcap Calorimeter // CMS DN-17-010.
[2] IBR-2 Reactor Parameters. Available at: http://flnph.jinr.ru/en/facilities/ibr-2/parameters
(accessed 19.11.2019)
[3] MPPC. Available at: http://www.hamamatsu.com/ (accessed 19.11.2019)
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