INAS Detectors for Infrared Astronomy

We propose InAs as a superior alternative to mercury cadmium telluride (MCT) for NASA#39;s astronomy applications in the visible to extended shortwave infrared (eSWIR) spectral band: 0.7 - 2.5 microns. A key performance parameter, the dark current density, can be achieved by cooling the InAs 20K more than MCT with 2.3 micron cutoff. In return, the InAs will extend spectral coverage to 3.0 microns and offer higher yield, lower cost, and greater availability due to the leveraging of mature group III-V growth/process equipment. In Phase I, we demonstrated an InAs focal plane array (FPA) with spectral response from 450 nm to 3000 nm, quantum efficiency ~ 70% in this wide band, and a low dark current that dropped exponentially with cooling. In Phase II, we will further improve material quality, expand array format to 1Kx1K, and deliver a megapixel camera to NASA for evaluation for astronomy.