Particle-induced spatial dark current fluctuations in focal plane arrays

An analytic calculation which describes the pixel-to-pixel variation in the particle-induced dark current distribution of a focal plane array is developed. The most important contributions to the dark current variance are shown to be the variations in the number of primary interactions, the energies of the primary recoils produced, and the charge emission from radiation-induced defects due to that electric field distribution. Microdosimetry theory provides a general approach for calculating the dark current variance for any incident particle for which the moments of the recoil spectrum are known and is shown to predict the dark current response successfully for neutrons and protons