A silicon photomultiplier with >30% detection efficiency from 450–750nm and 11.6μm pitch NMOS-only pixel with 21.6% fill factor in 130nm CMOS

A 16×16 Silicon Photomultiplier (SiPM) is reported in a 130nm CMOS imaging technology with a photon detection probability of >;30% from 450-750nm. The SiPM demonstrates a 21.6% fill factor with an 11.6μm pitch and 8μm diameter SinglePhoton Avalanche Diodes (SPADs). This is achieved using a new SPAD structure with integrated resistor and capacitor. NMOS-only pixel electronics are used to improve fill factor and to implement an addressable array of SPADs that are isolated from the array and column load. A 1T DRAM in each pixel is implemented to inhibit the output of high dark count rate (DCR) SPADs. The SiPM also achieves: a median DCR of ≈200Hz at 1.2V excess bias; low after pulsing; and a SPAD timing jitter of ≈95ps at 654nm with a column delay of ≈100-200ps.