InAs/GaSb Superlattice Infrared Detectors

Fraunhofer IAF develops type-II superlattice (T2SL) infrared (IR) detectors for the mid- (3‑5 µm, MWIR), long-wavelength (8-12 µm, LWIR) and very long-wavelength (>12 µm, VLWIR) regimes. The highly flexible T2SL detector technology allows covering of a wide range of applications from high-operating temperature (HOT) single element IR detectors, e.g., for laser-based sensing systems, to cooled focal plane array (FPA) detectors for high-performance imaging cameras. The freedom of design inherent to InAs/GaSb T2SLs is used to realize novel device types based on heterojunction concepts to suppress several dark current components. In the LWIR, our first heterojunction-based FPAs with a spatial resolution of 640x512 pixels on a 15 µm pixel pitch already reach a noise equivalent temperature difference (NETD) below 30 mK with F/2-optics against a 300 K background. The present talk will summarize the results achieved so far and give an overview of the ongoing development T2SL detector technology work at Fraunhofer IAF.