Difference between revisions of "Test Setup for SiPMs"
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* Pulse Generator: [http://www.testequipmentdepot.com/usedequipment/hewlettpackard/signalgenerators/8116a.htm HP 8116A] (GPIB) | * Pulse Generator: [http://www.testequipmentdepot.com/usedequipment/hewlettpackard/signalgenerators/8116a.htm HP 8116A] (GPIB) | ||
* Picoamp Meter: [http://www.teknetelectronics.com/Search.asp?p_ID=11201&pDo=DETAIL Keithley 485] (GPIB) | * Picoamp Meter: [http://www.teknetelectronics.com/Search.asp?p_ID=11201&pDo=DETAIL Keithley 485] (GPIB) | ||
+ | |||
+ | ==== Gain ==== | ||
+ | |||
+ | # Measure ADC spectrum w. or w./o light source | ||
+ | # Measure distance between peaks, calculate the corresponding charge and then gain | ||
+ | |||
+ | ==== Photo Detection Efficiency (PDE) ==== | ||
+ | |||
+ | * Continuous method (DC mode): overestimated due to cross-talk and after pulsing | ||
+ | # Measure draw current with calibrated light input | ||
+ | # Divide current by gain and photon flux to get "PDE" | ||
+ | |||
+ | * Pulse mode | ||
+ | # Measure ADC spectrum triggered by calibrated pulse light source | ||
+ | # Fit the spectrum by the function derived [http://argus.phys.uregina.ca/cgi-bin/private/DocDB/ShowDocument?docid=1553 here] to extract detected number of photons and cross-talk/after pulsing | ||
+ | # Divide the detected number of photons by input to get PDE | ||
+ | |||
+ | ==== Cross-Talk/After Pulsing ==== | ||
+ | |||
+ | * Cross-Talk and After Pulsing are sometimes mixed, in this context they are defined base on the timing: | ||
+ | # '''Cross-Talk''' means fast secondary signals which happen almost simultaneously with the primary signal which are likely due to the secondary photon generated by the primary signal leaked to adjacent pixels. | ||
+ | # '''After Pulsing''' means slow secondary signals which happen after the primary signal which are likely due to the delayed release of trapped electrons. | ||
+ | |||
+ | * Threshold method | ||
+ | # Pure measurement with dark noise | ||
+ | # This method is mainly sensitive to Cross-Talk. | ||
+ | # Set threshold of counter at 0.5, 1.5 and 2.5 photon electrons, compare the rates at different rates to extract Cross-Talk. | ||
+ | # Formalism to extract cross-talk is still needed to be derived, effect of pile up and after pulsing needed to be taken into account. | ||
+ | |||
+ | * ADC method | ||
+ | # Same method as '''pulse mode''' discussed in the PDE measurement | ||
+ | |||
+ | * Flash method | ||
+ | # Use Oscilloscope or Flash ADC to record the time spectrum with very weak but instantaneous light input (laser for example), | ||
+ | # By comparing the shape of the time spectrum from the single photon events with all events to extract after pulsing | ||
+ | # Such a method was discussed in [http://www.jlab.org/Hall-D/software/wiki/index.php/SiPM_Radiation_Hardness_Test#Study_with_Very_Small_Signal_Input SiPM radiation test] | ||
==== | ==== |
Revision as of 13:09, 23 December 2010
Contents
Test of First Article of Hamamatsu SiPMs
Time Line
- Mid Feb.2012: 10-20pcs partial shipment of first article units
- Mid Mar.2012: Delivery remainder first article units (60-70pcs)
- End Apr.2012: First article approval
- End Jul.2012: 1st delivery 500pcs
- End Aug.2012: 2nd delivery 500pcs
- End Sept.2012: 3rd delivery 120pcs
Test Items and Instruments Needed
General Devices
- Central Machine: Windows XP computer with LabVIEW 2009 installed (USB)
- VME controller: Wiener VM-USB (USB to VME)
- QDC: CAEN V792 (VME)
- Oscilloscope: Unknown
- Temperature sensor: Unknown
- Low voltage power supply: multiple output
- Bias voltage power supply: B&K 1787B (RS232)
- Pulse Generator: HP 8116A (GPIB)
- Picoamp Meter: Keithley 485 (GPIB)
Gain
- Measure ADC spectrum w. or w./o light source
- Measure distance between peaks, calculate the corresponding charge and then gain
Photo Detection Efficiency (PDE)
- Continuous method (DC mode): overestimated due to cross-talk and after pulsing
- Measure draw current with calibrated light input
- Divide current by gain and photon flux to get "PDE"
- Pulse mode
- Measure ADC spectrum triggered by calibrated pulse light source
- Fit the spectrum by the function derived here to extract detected number of photons and cross-talk/after pulsing
- Divide the detected number of photons by input to get PDE
Cross-Talk/After Pulsing
- Cross-Talk and After Pulsing are sometimes mixed, in this context they are defined base on the timing:
- Cross-Talk means fast secondary signals which happen almost simultaneously with the primary signal which are likely due to the secondary photon generated by the primary signal leaked to adjacent pixels.
- After Pulsing means slow secondary signals which happen after the primary signal which are likely due to the delayed release of trapped electrons.
- Threshold method
- Pure measurement with dark noise
- This method is mainly sensitive to Cross-Talk.
- Set threshold of counter at 0.5, 1.5 and 2.5 photon electrons, compare the rates at different rates to extract Cross-Talk.
- Formalism to extract cross-talk is still needed to be derived, effect of pile up and after pulsing needed to be taken into account.
- ADC method
- Same method as pulse mode discussed in the PDE measurement
- Flash method
- Use Oscilloscope or Flash ADC to record the time spectrum with very weak but instantaneous light input (laser for example),
- By comparing the shape of the time spectrum from the single photon events with all events to extract after pulsing
- Such a method was discussed in SiPM radiation test