Silicon Photomultipliers With 8-Mu M Thick Substrate For Enhancing Photo-Sensitivity In The 900-Nm Range And Reducing Afterpulse And Delayed Crosstalk

Light detection and ranging (LiDAR) systems are potential candidates as sensing systems for autonomous driving. Light sensor performance is highly related to the distance measuring capabilities of the LiDAR system. Silicon photomultipliers (SiPM) have attracted attention because of their capability for detecting even single photons of light [1]. To increase the utilization efficiency of incident light, we thinned the SiPM substrate for light reflectance in the structure to a thickness of 8 mu m. This improved photon detection efficiency (PDE) to 1.6 times that of a 700- mu m device at an exceeding voltage of 4.0 V above the avalanche breakdown voltage. By reducing diffusion carriers from the substrate, time- lagged signals such as afterpulse or delayed crosstalk were suppressed to 60 %.