Three-dimensional excess carrier distribution in semiconductor imaging arrays

The distribution of excess carriers in the three dimensions of a semiconductor in closely packed sensing arrays is analytically derived using a novel three-dimensional simulation. In addition to the introduction of lateral transport, the results show significant deviation from the distribution obtained out of the one-dimensional model, both in magnitude and gradients. Thus, the net flow of carriers is drastically different than previously predicted. The technical implications of the exact three-dimensional distribution on quantum efficiency and crosstalk is visualized. The effects of physical parameters such as absorption coefficient, diffusion length, array geometry, and detector structure are thoroughly investigated.