Mid-wavelength infrared high operating temperature pBn photodetectors based on type-II InAs/InAsSb superlattice

A high operating temperature mid-wavelength infrared pBn photodetector based on the type-II InAs/InAsSb superlattice on a GaSb substrate has been demonstrated. At 150 K, the photodetector exhibits a peak responsivity of 1.48 A/W, corresponding to a quantum efficiency of 47% at -50 mV applied bias under front-side illumination, with a 50% cutoff wavelength of 4.4 mu m. With an R x A of 12 783 omega cm(2) and a dark current density of 1.16 x 10(-5) A/cm(2) under -50 mV applied bias, the photodetector exhibits a specific detectivity of 7.1 x 10(11) cm Hz(1/2)/W. At 300 K, the photodetector exhibits a dark current density of 0.44 A/cm(2) and a quantum efficiency of 39%, resulting in a specific detectivity of 2.5 x 10(9) cm Hz(1/2)/W.