Modeling and simulation of CMOS APS

This work studies the importance of the peripheral collection in the overall photoresponse in deep sub-micron CMOS 3T active pixel sensors (APS), focusing on the contribution of the bottom surface of the depletion region. We analyze a semi-analytical expression, inspired by previous works, that models the photoresponse of a set of fabricated pixels with octagonal photodiodes that could be easily extended to different geometries. Device simulation results are used to study the behaviour of these structures with the purpose of using computer aided design (CAD) tools for the next technological nodes research.