There are no common standards for testing the reliability of SiPMs. However, SensL have taken advantage of the fact that their devices are manufactured using CMOS processes and applied industry standard test flows designed for ICs.
Using the Joint Electron Device Engineering Council (JEDEC) standard JESD22-A108D “Temperature, bias and operating life” SensL have tested multiple wafer production and package assembly batches to produce the most comprehensive SiPM reliability assessment available.
This publication details CMOS foundry fabrication, reliability stress assessment, and packaged sensor test results obtained during qualification of the SensL B-Series silicon photomultiplier (SiPM). The same procedures have been applied to the C-Series SiPMs and all subsequent Series.
SiPM sensors with active-area dimensions of 1, 3, and 6mm were fabricated and tested to provide a comprehensive review of SiPM performance highlighted by fast output rise times of 300ps and photon detection efficiency of greater than 41%, combined with low afterpulsing and crosstalk.
Measurements important for medical imaging positron emission tomography systems that rely on time-of-flight detectors were completed. Results with LSYO:Ce scintillation crystals of 3 × 3 × 20 mm³ demonstrated a 225 ±2ps coincidence resolving time (CRT), and the fast output is shown to allow for simultaneous acquisition of CRT and energy resolution.
The wafer level test results from ~150,000 3mm SiPM are shown to demonstrate a mean breakdown voltage value of 24.69 V with a standard deviation of 0.073 V. The SiPM output optical uniformity is shown to be ±10% at a single supply voltage of 29.5V.
Finally, the reliability stress assessment is detailed and shown to have been completed with all SiPM passing. This is the first qualification and reliability stress assessment program run to industry standards that has been reported on SiPM’s.
|SiPM high volume production, performance and reliability assessment|