SiPMs for solar neutrino detector? J. Kaspar, 6/10/14 1 SiPM is - - PowerPoint PPT Presentation

SLIDE 1

SiPMs for solar neutrino detector?

• J. Kaspar, 6/10/14

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SLIDE 2

SiPM is

• take a photo-diode
• reverse-bias it above breakdown voltage


(Geiger mode avalanche photo diode)

• add quenching resistor
• repeat many thousand times

2

VAPD

full depletion

photodiode APD

Geiger Mode

APD

SLIDE 3

Huge variety of products

Hamamatsu
 KETEK
 SensL
 Philips
 ST Microelectronics 1x1 – 26 x 26 mm 10 – 200 um pixels

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SLIDE 4

Theory of operation

• each pixel is an independent detector
• when pixel fires, it delivers charge (~1e6 electrons)


(regardless how many photons hit the pixel)

• then the pixel is dead for ~100 nsec (recovery time)
• ~1000 times more pixels on the device than photons

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SLIDE 5

Advantages

• fast like PMT, compact, cheap
• runs in magnetic fields, is non-magnetic
• high photo detection efficiency
• low voltage (typ. 40 or 70 V, diode orientation)
• much lower radioactivity than PMT

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SLIDE 6

Disadvantages

• temperature dependence


photo-effect (sec. order, cryo)
 probability electron triggers avalanche discharge
 gain (charge delivered by a pixel when it fires)
 breakdown voltage


• > temperature monitoring

• > in situ calibration


(0,1,2 ph comb, or laser)

• batteries not included


no standard pre-amplifier (think PMT without a base)

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• 1

2 3 4 5 6 7 8 9

Frequency (number of events) Number of detected photons

(M=1.25 × 106) 3000 2500 2000 1500 1000 500

SLIDE 7

Cryo compatible

• photon absorption length depends on temperature
• easy down to 100 K (SiPMs like that)
• modified runs well in LXe, LAr


anti-reflective coating (UV eff), cryo comp package
 K.Sato NIM A 732, 2013 (427–430)

• charge carrier freeze-out < 50 K

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SLIDE 8

Historical artifacts

• cross-talk -> optical trenches
• after-pulsing -> Si wafer purity
• high dark rate -> Si wafer purity
• slow pulses, pulse dependent on temperature ->


metal (Ni) based quenching resistor

• high cost -> now much cheaper than PMT

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SLIDE 9

cross-talk

• real photons emitted


during avalanche discharge

• problem for stat properties of pulses


e.g. mean over sigma squared proxy
 for number of pixels fired

• optical trenches

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SLIDE 10

after-pulsing

• incomplete discharge
• part trapped
• delayed release

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SLIDE 11

metal quench resistor

pulse decay time:
 R (quench resistor) *
 C (diode) poly-crystalline Si (old) Ni based (new)

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SLIDE 12

examples of use

• Cerenkov telescopes (CTA)


single photons, shaping, clipping,
 pole-zero correction

• hadron calorimeters


~1000 photons
 Cerenkov, fast scint, or both

• positron emission tomography


TOF

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SLIDE 13

pre-amplifier

batteries not included (like a PMT without a base) 3 possible designs:

• voltage amplifier with a shunt resistor


pulse shapes ~40 nsec

• discrete trans-impedance amplifier


pulse shapes ~10 – 20 nsec

• integrated trans-imp. amplifier


pulse shapes ~5 nsec

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SLIDE 14

g-2 example

• anomalous dipole moment

• f muon
• segmented lead fluoride


calorimeter (Cerenkov)

• readout by SiPMs


25 – 4000 photons
 per event

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SLIDE 15

SiPM board design goals

• energy scale (gain) stability


comes from pulse amplitude
 0.1 % (short time stability)

• timing resolution, time scale accuracy


comes from the leading edge
 ~30 ps (different crystals), ~50 ps (pile-up)

• pulse width


leaked energy vs. direct hit, lost muon
 SiPM board should preserve light profile

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SLIDE 16

Monolithic design

S12642-0404PA-50
 16 channel array
 12x12 mm2 (active) area
 50 µm pixels
 Ni-based quench. resistor
 through silicon vias


• ptical trenches


high purity Si wafer 25 – 4000 photons

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SLIDE 17

LMH6881 fully differential op-amp
 variable gain (6–26dB), SPI
 thermal coupling to crystal AC coupled output
 2 MMCX connectors feeding
 twinax cable 2x THS3202 dual op-amp
 each sums 4 SiPM channels THS3201 at unity gain
 sums four 4-sums

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SLIDE 18

Knobs to turn

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1 1 2 2 3 3 4 4 5 5 A A B B C C

Date: 12 mar 2014 KiCad E.D.A. Rev: Size: A4 Id: 1/1 Title: File: SiPM 4 Ch Test Board Mk 9.sch Sheet: / PGA CS- CLK SDI PGA SDO

+5V

1 2 D4 S12572-025 1 2 D3 S12572-025 1 2 D2 S12572-025 1 2

C14 0.01u

1 2

C12 0.01u

R7

49.9

R2

49.9

+5V

1 2

C16 0.1u

1 2

C20 0.1u

R10

1.0K

R9

3.0K

1 2

C8 1u

+5V

1 2

C9 0.01u

1 2

C6 0.01u

1 2

C4 0.01u

1 2

C7 0.01u

1 2

C15 0.1u

R6

49.9

1 2

C11 0p

1 2

C13 0.1u

R4

49.9

+5V

• 5V

1 2

C1 100p

1 2

C2 0.1u

1 2

C3 6.8u

1 2

C19 6.8u

1 2

C18 0.1u

R8

49.9

1 2

C17 100p

R1

4.99

R5

2

R3

24.9

1 2

C5 1u

1 2

C10 0.01u

1 2 D1 S12572-025

+

• SOT23-5

Vout 1 Vs- 2 +In 3

• In

4 Vs+ 5

U1 THS3201

OCM 2

D1

3

D0

4

SPI

5 GND 6 GND 7 INMS 8 INMD 9 INPD 10 Vcc 20 INPS 11 OUT- 21 GND 12 OUT+ 22 GND 13 Vcc 23 Vcc 24

D2

15 GND 25

D3

16 SD 17 Vcc 19

U2 LMH6881 R12

270

PGA SDO

TDMS_Data_2+

1

TDMS_Data_2_Shield

2

TDMS_Data_2-

3

TDMS_Data_1+

4

TDMS_Data_1_Shield

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TDMS_Data_1-

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TDMS_Data_0+

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TDMS_Data_0_Shield

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TDMS_Data_0-

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TDMS_Clock+

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TDMS_Clock_Shield

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TDMS_Clock_-

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CEC

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NC

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DDC_Clock

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DDC_Data

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Ground

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+5V_Power

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Hot_Plug_Det

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P1 HDMI Bias Bias Return Bias Bias Return R11 Zero ohms to connect shield, Open for shield connected to Bias supply only. Out + Out - Out + Out -

+5V

CLK SDI PGA SDO PGA CS-

• 5V

SiPM anode to ground SiPM anode to virtual ground

SLIDE 19

Pulse shape

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intrinsic pulse
 (no pole zero correction) response to 2.5 nsec LED jitter from the pulse gen

10 ns

SLIDE 20

High rate capable

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~5 MHz laser shots
 2000 photons per shot jitter from the pulse gen

SLIDE 21

pileup resolution

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SLIDE 22

pileup resolution

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SLIDE 23

Summary

Geiger mode avalanche photodiodes Advantages:

• fast, compact, cheap, low-voltage devices, high detection efficiency
• much lower radioactivity than PMT
• cryo friendly

Disadvantages and Challenges

• requires custom readout board
• gain is sensitive to temperature; must control environment

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