Demonstration of type-II superlattice MWIR minority carrier unipolar imager for high operation temperature application.

ABSTRACT

An InAs/GaSb type-II superlattice-based mid-wavelength infrared (MWIR) 320×256 unipolar focal plane array (FPA) using pMp architecture exhibited excellent infrared image from 81 to 150 K and ∼98% operability, which illustrated the possibility for high operation temperature application. At 150 K and -50 mV operation bias, the 27 µm pixels exhibited dark current density to be 1.2×10(-5) A/cm(2), with 50% cutoff wavelength of 4.9 µm, quantum efficiency of 67% at peak responsivity (4.6 µm), and specific detectivity of 1.2×10(12) Jones. At 90 K and below, the 27 µm pixels exhibited system limited dark current density, which is below 1×10(-9) A/cm(2), and specific detectivity of 1.5×10(14) Jones. From 81 to 100 K, the FPA showed ∼11 mK NEDT by using F/2.3 optics and a 9.69 ms integration time.