Inverse doping profile extraction as an enabling tool for accurate SPAD modeling

Abstract

Physical models are key tools for developing new SPADs structures. However, as most SPADs characteristics strongly depends on the electric field, a precise knowledge of the doping profile is required. Unfortunately, common profiling techniques are not accurate enough. To cope with this problem, we developed an inverse approach which resorts to the combined use of electrical simulations and capacitance-voltage measurements. We applied the technique to multiple SPADs and we used the extracted profile to calculate their breakdown voltages. Simulated results closely matching the experimental outcomes provide us a strong validation of the proposed extraction technique.