High Operating Temperature Midwave Infrared InAs/GaSb Superlattice Photodetectors on (111) GaSb Substrates

We report on the detailed radiometric characterization of midwave infrared (MWIR) (100% cutoff wavelength, i.e., λ
_100%
, was 5.6 μm at 295 K) InAs/GaSb type-II strained layer superlattice (T2SL) detectors grown on the GaSb (111) substrate. At 295 K and 4 μm, a dark current density J
d
of 0.53 A/cm
²
(at -50 mV) and specific detectivity D* = 8.5 × 10
⁹
Jones (at 0 V) were demonstrated, which are superior values to the state-of-the-art MWIR T2SL detectors with the same (p-i-n) design grown on conventional GaSb (100) substrates.