There are no common standards for testing the reliability of SiPMs. However, KETEK have taken advantage of the fact that their WB-Series SiPMs are manufactured using CMOS processes and applied industry standard test flows designed for ICs.
The tests were carried out at the Electronic Packaging and Sensor Laboratory of the University of Applied Sciences, Munich, under Prof. Dr. Gregor Feiertag.
The reliability tests were performed according to the qualification plan defined by KETEK. Standard conditions for the use of the devices were assumed when the test schedule was defined so additional testing may be necessary if the devices are used under special conditions.
MSL1 classification and pre-conditioning was performed before all tests with devices being classified as "good" if a diode test proved electrical connection between BGA and chip. Optical inspection was carried out after each diode test.
- Pre-conditioning / MSL classification to J-STD-020
- Temperature Cycling to JESD22-A104
- High Humidity High Temperature Storage to JESD22-A101
- High Temperature Storage to JESD22-A103
- Combined Test: Temp. Cycling, High Humidity High Temp.Storage & High Temp.Storage
- Electro Static Discharge
Mechanical Stability was also tested. Devices were soldered to PCBs using the soldering temperature profile, footprint and solder paste specified in the PM33-WB-series datasheet. The shear force and pulling force needed to disassemble the devices was measured.
- Mean shear force after soldering: 40.5 N; standard deviation: 2.5 N
- Mean pulling force after soldering: 34.7 N; standard deviation: 4.3 N
After reliability testing was completed 24 devices were tested for spectroscopic performance (DCR, CTP, PDE@406nm) to verify that there was no change in the performance of the silicon chip itself.
|KETEK SiPM high volume surface mount package qualification report|