A Near-Infrared Enhanced Silicon Single-Photon Avalanche Diode With a Spherically Uniform Electric Field Peak

A near-infrared (NIR) enhanced silicon single-photon avalanche diode (SPAD) fabricated in a customized $0.13~\mu \text{m}$ CMOS technology is presented. The SPAD has depleted absorption volume of approximately notation="LaTeX">$15\,\,\mu \text{m}\,\,\times 15\,\,\mu 18\,\,\mu . Electrons generated the region are efficiently transported by drift to central active with diameter notation="LaTeX">$2~\mu At operating voltage, contains spherically uniform field peak, enabling multiplication electrons originating from all corners device. advantages architecture include high NIR photon detection efficiency (PDE), drift-based transport, low afterpulsing, and compatibility an integrated readout. front-side illuminated device characterized. PDE 13% at wavelength 905 nm, afterpulsing probability < 0.1% for dead time 13 ns, median dark count rate (DCR) 840 Hz room temperature. shows promising performance time-of-flight applications that benefit NIR-sensitive arrays.