A wide spectral range Single-Photon Avalanche Diode implemented in 65nm standard CMOS Technology

This paper presents a wide spectral range Single-Photon Avalanche Diode (SPAD) implemented in 65nm standard CMOS (Complementary Metal Oxide Semiconductor) Technology. The wide wavelength sensitivity is achieved using the p-type substrate layer instead of using a different well implanted inside the substrate. The higher electron impact ionization coefficient in compare with the hole impact ionization coefficient results in an increase in the photon detection probability (PDP) in the larger wavelengths. Low PDP in compare with the older technologies is predictable according to the higher doping profiles of the modern deep-submicron technologies. Both the optical emission from the active region and spectral response detection is measured and analyzed in this paper.