An interdigital SiPM with coincidence measurement for rejection of dark noise

Dark noise caused by thermally generated carriers in avalanche region is one of the main obstacles for photon detection with silicon photomultiplier (SiPM), especially in low light level detection. Coincidence measurement is an effective method for reducing the dark noise. This manuscript investigates a specially designed interdigital SiPM with coincidence measurement based on a digital oscilloscope, which can realize remarkable suppression of the dark noise and measure the weak light precisely. Employing the presented SiPM and the coincidence method, the dark pulse rate of SiPM was reduced to 1.69% of the results without coincidence method; the pulses area distribution for low light level detection was improved with high resolution and the spectrum obeys Poisson distribution. The reduction of dark noise was quite in agreement with the coincidence theory calculation.