Research Progress of InAs/GaSb Type-Ⅱ Superlattice Long-wave Infrared Detector

In this study, the research progress of long-wave infrared detectors based on InAs/GaSb type-Ⅱ superlattices (T2SLs) is systematically reported. The advantages and disadvantages of various device structures based on GaSb and InAs substrates are compared and analyzed from the perspective of substrate, material growth, and device performance. The results show that the structure of the device with InAs as the substrate, InAs/InAs_1-xSb_x as the absorber material, and PB₁IB₂N type is a relatively optimized design. Combining the multilayer structure design of ZnS and Ge, a heavy doping buffer layer, and the inductively coupled plasma (ICP) dry etching process, the 50% cutoff wavelength of the device can achieve 12 μm, the quantum efficiency (QE) can be increased to more than 65%, and the dark current density can be reduced to 1×10^-5 A/cm². Finally, the future development trend of InAs/GaSb T2SLs long-wave infrared detectors is summarized.