XBn and cascade infrared detectors for mid-wave range and HOT conditions

Unlike thermal detectors, infrared photon detectors normally operate at cryogenic temperatures to suppress the noise coming from mechanisms associated with the inherited capability of the narrow band gap materials. The potential applications of the infrared detectors require systems with low cost, size, weight, power consumption and what is the most important, high operating temperature condition. The very first attempts to reach high operating temperature conditions were concentrated on photoconductors and photoelectromagnetic detectors. Next, non-equilibrium detector design with Auger suppression and optical immersion were introduced. Currently, a new approach related to barrier structures and interband cascade infrared devices has been successfully put into practice. Among the high operating temperature materials the following should be enumerated: HgCdTe, InAsSb, and type-II InAs/GaSb superlattices. The paper presents recent strategies: barrier and cascade structures to increase performance at high operation temperature conditions.