Monolithic CMOS detector module for photon counting and picosecond timing

A monolithic optoelectronic module for counting and timing single optical photons has been designed and fabricated in CMOS technology. It integrates a single-photon avalanche diode (SPAD) of 12 μm-diameter with a complete active-quenching and active-reset circuit. The detector operates in Geiger-mode biased above breakdown level, with overvoltage adjustable up to 20 V. The on-chip electronics detects the rise of the current triggered by a photogenerated carrier, then swiftly quenches the avalanche by controlling the SPAD bias voltage, and finally resets the detector after a hold-off time (adjustable from 0 to 350 ns). In a chip of 700 μm×1,000 μm, the overall performance is comparable or better than that of macroscopic modules available from leading industries.