Multiscale Modeling of Radiation Events in Infrared Photodetectors

Sivananthan Laboratories, Inc. (Sivananthan Labs) will create a multiscale model capable of predicting the immediate and long-term effects of radiation events in operating and dormant infrared (IR) photodetector devices. Although extensible to any IR gap semiconductor and device architecture, the model will initially be developed for and applied to mid-wavelength IR (MWIR) and long-wavelength IR (LWIR) photodetectors composed of Ga-free Type-II superlattice (T2SL) materials with the nBn device architecture. The multiscale model starts with atomistic, Newtonian simulations of radiation events to predict the distribution and scale of radiation-induced crystal defects. First principles, quantum mechanical calculations predict the electronic states created by these extended defect clusters, including their influences on carrier lifetime and generated dark currents. These electronic effects are then included into a model of the device to calculate the new performance, based on the location of the radiation event. A library of events is compiled to support stochastic modeling of accumulated damage and device degradation. Simulation of performance recovery solutions, such as on-orbit annealing, and consideration of secondary radiation effects can be supported. Approved for Public Release | 22-MDA-11215 (27 Jul 22)