Low Dark Count Single-Photon Avalanche Diode Structure Compatible With Standard Nanometer Scale CMOS Technology

A single-photon avalanche diode structure implemented in a 130-nm imaging process is reported. The device employs a p-well anode, rather than the commonly adopted p+, and a novel guard ring compatible with recent scaling trends in standard nanometer scale complementary metal-oxide-semiconductor technologies. The 50-mum ² active area device exhibits a dark count rate of 25 Hz at 20 ^degC and a photon detection efficiency peak of 28% at 500 nm.