Demonstration of MOCVD-Grown Long-Wavelength Infrared InAs/GaSb Superlattice Focal Plane Array

High-performance InAs/GaSb type-II superlattice infrared detectors and focal plane arrays (FPAs) are normally grown by molecular beam epitaxy (MBE). In this work, we demonstrate the flrst long-wavelength infrared InAs/GaSb superlattice FPA grown by metalorganic chemical vapor deposition (MOCVD) with clear image. High-quality superlattice material was obtained evidenced by sharp X-ray diffraction peaks and atomic flat surface. Electrical and optical measurements performed on single element detectors showed a 50% cut-off wavelength of similar to 10.1 mu m, a dark current density of 2.5 x10(-5) A/cm(2), a peak responsivity of 0.88 A/W and a peak detectivity of 1.7 x 10(11) cm.Hz(1/2)/W at 80 K. A 320 x 256 FPA with 30 mu m pixel pitch was then fabricated. With an integration time of 1.9 ms and an applied bias of -0.1 V, the FPA shows an average operability of 96.96%, a non-uniformity of 4.97%, a noise equivalent temperature difference of 51.1 mK and a peak detectivity of 2.3 x 10(10) cm.Hz(1/2)/W at 80 K without thinning down the substrate.