Advanced MWIR/LWIR Multi-Spectral Detectors

Hyperspectral imaging arrays offer far more data and the ability to discriminate objects being observed. Continued difficulties with applying HgCdTe materials, especially for LWIR, present an opportunity for the development of alternate materials. One such candidate for MWIR/LWIR photodetectors are InAsSb alloys and short period Type-II superlattices based on InAs/GaInSb. This superlattice structure has the ability to tune the cutoff wavelengths during device fabrication and yet be amenable to the creation of multi-spectral serially-positioned pixels. One of the issues this Phase I program will address is the intermixing of Arsenic and Antimony at the superlattice interfaces, which can hamper LWIR operation. Improved superlattice growth will be achieved through the application of newly developed MBE apparatus.