An analytical, aperture, and two-layer carrier diffusion MTF and quantum efficiency model for solid-state image sensors

Abstract

A two-dimensional analytical model is formulated for calculating the pixel response, modulation transfer function (MTF), and quantum efficiency of front-side illuminated, solid-state image sensors. Included in this unified model are the effects of lateral diffusion of charge carriers within a two-layer substrate and less than full pixel sampling apertures. The results of this model are compared to those of a numerical, three-dimensional Monte Carlo algorithm and to the analytical results reported by Blouke and Robinson. We find good agreement between the quantum efficiency and MTF calculated by the present model and by the three-dimensional Monte Carlo method. However, we find higher quantum efficiency and lower MTF than the previously reported analytical two-layer model. The unified aspect of the present model correctly combines the effects of sampling aperture and lateral diffusion.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>