Low Dark Count Geiger Mode Avalanche Photodiodes Fabricated in Conventional CMOS Technologies

Avalanche photodiodes operated in the Geiger mode present very high intrinsic gain and fast time response, which make the sensor an ideal option for those applications in which detectors with high sensitivity and velocity are required. Moreover they are compatible with conventional CMOS technologies, allowing sensor and front-end electronics integration within the pixel cell. Despite these excellent qualities, the photodiode suffers from high intrinsic noise, which degrades the performance of the detector and increases the memory area to store the total amount of information generated. In this work, a new front-end circuit that allows low reverse bias overvoltage sensor operation to reduce the noise in Geiger mode avalanche photodiode pixel detectors is presented. The proposed front-end circuit also enables to operate the sensor in the gated acquisition mode to further reduce the noise. Experimental characterization of the fabricated pixel with the conventional HV-AMS 0.35 μm technology is also presented in this article.