Simulation and Measurement Framework for Bridging QE and PDP in UV–VIS FSI SPADs

Abstract - This work presents a simulation and measurement methodology for modeling the Photon Detection Probability (PDP) of Front-Side Illuminated (FSI) CMOS Single-Photon Avalanche Diodes (SPADs) across the ultraviolet visible (UV–VIS) range, achieving over 40% PDP between 
375 nm and 465 nm with 2 V of excess bias above avalanche breakdown. Accurate PDP predictions across temperatures, voltages, and process variations have been achieved by combining modeled absorption profiles, measured quantum efficiency, and avalanche breakdown simulations without relying on fitting parameters.