Compact Modeling of Charge Transfer in Pinned Photodiodes for CMOS Image Sensors

Raffaele Capoccia, Assim Boukhayma, Farzan Jazaeri, Christian Enz
2019 IEEE Transactions on Electron Devices  
In this paper, we propose a physics-based compact model of the pinned photodiode (PPD) combined with the transfer gate. A set of analytical expressions is derived for the 2-D electrostatic profile, the PPD capacitance, and the charge transfer current. The proposed model relies on the thermionic emission current mechanism, the barrier modulation, and the full-depletion approximation to obtain the charge transfer current. The proposed physics-based model is fully validated with technology
more » ... technology computer-aided design simulations, i.e., stationary and optoelectrical simulations. The development of such a compact model for PPD represents an essential step toward the design, simulation, and optimization of PPD-based pixels in CMOS image sensors. Index Terms-Charge transfer, CMOS image sensors (CISs), compact modeling, pinned photodiode (PPD).
doi:10.1109/ted.2018.2875946 fatcat:5yobpk6z4zhq3igvtvjsljv4b4