Radiation Hardened MWIR

Space-based imaging applications for mid-wave infrared (MWIR) focal plane arrays (FPAs) require minimal performance degradation over the lifetime of their mission. The two distinct damage mechanisms in this operational environment are ionization damage and displacement damage. The ionization damage results in generation of electron-hole pairs that can become trapped and manifest as surface currents, while the physical damage generates vacancies in the crystal lattice where electron-hole recombination can occur shortening the minority carrier recombination lifetime.  The minority carrier lifetime is a key performance parameter as it affects the dark current and quantum efficiency (QE) of the detector. In this Phase II program, Attollo Engineering is proposing to leverage its commercial MWIR FPA and perform a comprehensive characterization of the radiation tolerance of the strained-layer superlattice-based MWIR photodetectors and improve the design based on that characterization to develop a radiation hardened MWIR camera that can be used in future space missions. To accomplish this goal, we will fabricate FPAs and single element detectors (SEDs) devices based on our existing detector design and explore new designs to improve radiation tolerance. We will build on our successful radiation testing experience in the Phase I program that we irradiated our standard SED and FPA devices and we will deliver 3 FPAs to the Navy customer for further testing.