InAs/InAsSb Type-II Superlattice Mid-Wavelength Infrared Focal Plane Array With Significantly Higher Operating Temperature Than InSb

• Main Authors: David Z. Ting, Sir B. Rafol, Sam A. Keo, Jean Nguyen, Arezou Khoshakhlagh, Alexander Soibel, Linda Hoglund, Anita M. Fisher, Edward M. Luong, Jason M. Mumolo, John K. Liu, Sarath D. Gunapala
• Format: Article
• Language: English
• Published: IEEE 2018-01-01
• Series: IEEE Photonics Journal
• Subjects: Infrared detector; photodetector; type-II superlattice; InAs/InAsSb; heterostructure; unipolar barrier
• Online Access: https://ieeexplore.ieee.org/document/8528821/
• ISSN: 1943-0655

We report focal plane array (FPA) results on a mid-wavelength InAs/InAsSb type-II strained layer superlattice (T2SLS) unipolar barrier infrared detector with a cutoff wavelength of 5.4 μm. For 300 K background in the 3-5-μm band, f/2 aperture, an FPA operating at 150 K exhibits a mean noise equivalent differential temperature (NEDT) of 18.5 mK, and an NEDT operability of 99.7%. The NEΔT distribution has a width of 8 mK, with no noticeable distribution tail, indicating excellent uniformity. The mean noise-equivalent irradiance is 9.1 × 10¹¹ photons/sec-cm². The mean quantum efficiency is 49.1% without antireflection coating, and the mean specific detectivity (D^*) is 2.53 × 10¹¹ cm-Hz^½/W. Benefitting from an absorber material with a much longer Shockley-Read-Hall minority carrier lifetime, and a device architecture that suppresses generation-recombination and surface-leakage dark current, the InAs/InAsSb T2SLS barrier infrared detector FPA has demonstrated a significantly higher operating temperature than the mid-wavelength infrared market-leading InSb.