A comprehensive CMOS APS crosstalk study: photoresponse model, technology, and design trends

In this paper the lateral photoresponse and crosstalk (CTK) in complementary metal-oxide-semiconductor (CMOS) photodiodes is investigated by means of a unique sub-micron scanning system (S-cube system) and numerical device simulation. An improved semi-analytical model developed for photoresponse estimation of a photodiode-based CMOS active pixel sensor reveals the photosignal and the CTK dependence on the pixels geometrical shape and arrangement within the array. The trends that promise to increase CMOS image sensor performance are presented and design tradeoffs intended to optimize the photoresponse and minimize CTK are discussed.