Passivation Innovations for Large Format Reduced Pixel pitch strained layer superlattice Focal Plane Array Imagers Operating in the Long

The proposed Phase II effort will focus on the fabrication and testing of high performance 640x512 long wavelength infrared (LWIR) type-II strained layer superlattice detector arrays. The effort will start with the modeling of devices and arrays, followed by improving the understanding of bulk defects to enhance carrier lifetimes. Passivation studies will continue based on the Phase I foundation, with an emphasis on stacked passivation layers with enhanced robustness. Molecular beam epitaxial growth and fabrication of nBn structures with low dark currents and high operating temperatures will be undertaken. The dry etching of small features appropriate for short pixel pitches (15 µm) will be carried out to study etch uniformity and surface morphologies, which will be of great benefit to the realization of high performance, large format arrays. The fabricated arrays will hybridized to read out integrated circuits suitable for 15 µm pixel pitches and LWIR detectors. The focal plane arrays will be tested and characterized in-house and by our collaborator L3-Com.