Improved Signal to Noise Ratio Across the Spectral Range for CMOS Silicon Photomultipliers

We report on a CMOS silicon photomultiplier (SiPM) with 9x18 microcells fabricated in a 0.5 mu m 2-poly 3-metal standard CMOS process. The microcells use perimeter gated single photon avalanche diodes (PGSPADs) to vary the SiPM device signal to noise ratio by modulating the electric field around the junction of the PGSPADs. Experimental measurements show that the SNR can be improved over a range of 1 to 1000 tuning the perimeter gate voltage and excess bias voltage. The technique allows for SNR optimization and tuning dependent on the application.