Impact of proton radiation on dark current of InAs/GaSb type-2 superlattice longwave infrared photodetector

In this communication, we present the electrical characterizations of InAs/GaSb type-2 superlattice (T2SL) long wavelength infrared (LWIR) barrier photodetectors under proton radiation. The set of irradiated LWIR detectors exhibited a 50% cut-off wavelength from 11 to 13 µm at 80 K and a p-type absorbing zone thickness from 1.5 to 5.5 µm. The irradiations were performed with 60 MeV protons and fluences up to 8x10
¹¹
H
⁺
/cm
²
. Dark current measurements were done before and after each irradiation step. We observed an increase of the dark current with increasing the displacement damage doses and such degradation of electrical performance depends neither on the cut-off wavelength nor on the thickness of the absorbing zone or on the number of T2SL periods.