Fabrication and Characterization of InAs/GaSb type-II Superlattice Long-Wavelength Infrared Detectors Aiming High Temperature Sensitivity

Noise equivalent temperature difference (NETD) is an important figure of merit for infrared detectors. Lower NETD means that the detector can realize smaller temperature resolution and longer range recognition. In this work, we investigate the device performance, especially the NETD characteristics of a long-wavelength infrared (LWIR) photodetector based on InAs/GaSb type-II superlattice (T2SL). To achieve mK-level temperature-sensitivity, the effect of detector's intrinsic and extrinsic factors on NETD performance has been discussed. Through a series of efforts, a NETD value of 7 mK was realized for a T2SL detector with a 100% cutoff wavelength of 11.4 μm at 77 K.