Hybrid infrared imaging arrays

Infrared focal planes in intrinsic semiconductors offer advantages over extrinsic semiconductors in both operating temperature and quantum efficiency. Current research on hybrid focal planes is directed toward devices in which detection occurs in an intrinsic narrow energy bandgap semiconductor, and signal processing is accomplished in a silicon multiplexer which is electrically interfaced to the detector array. Two principal hybrid device designs are being developed to sense the incident photon flux: frontside and backside illuminated configurations. These hybrid designs and the approaches using III-V, IV-VI and II-VI alloy systems are described. Furthermore, the devices which incorporate self spectral filtering and detector-multiplexer interface circuits will be described. The operation of existing focal planes and the key technical problems associated with the attainment of practical, high performance hybrid focal planes will be discussed.