The requirement for cooling below room temperature to limit thermal generation processes is the major drawback of infrared (IR) photon detectors. In order to obtain background limited performance (BLIP), the devices for the 3–5 μm spectral region are typically operating at T <200 K, while those for the 8–12 μm at 77 K. The current effort to produce near room temperature photon detectors (higher operating temperature conditions, HOT) are being concentrated on the interband cascade photodetectors (ICIP). That effort is mostly seen for longwave infrared (LWIR) devices operating at HOT conditions where the optimum absorber may be thicker compared to the carriers’ diffusion length, limiting the photogenerated carriers collection what leads to the decreasing of the quantum efficiency (QE) and the ultimate performance cannot be achieved in practice. The ICIP architecture allows to circumvent that issue. In addition to avoid the limitation imposed by the reduced diffusion length, the intersubband (IS) quantum cascade photodetectors (QCPs) were introduced in the early 2000s based on quantum-well infrared photodetectors (QWIPs) and quantum cascade lasers (QCLs). Those cascade detectors proved to be operating at low temperatures ~ 100 K. In this paper we present the current status of the ICIPs based on type-II superlattices (T2SLs) InAs/InAsSb n- and p-type doped active layers intended to be operating within LWIR range and HOT conditions - 210 K reached by thermoelectric coolers and room temperature. Immersed detector reached detectivity, D*~3×108 cmHz1/2/W at 300 K and wavelength, λ=10 μm.
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