Minority carrier lifetime in mid-wavelength interband cascade infrared photodetectors

Abstract

A simple and effective electrical method is developed to extract the thermal generation rate and minority carrier lifetime in type-II (T2) InAs/GaSb/Al(In)Sb superlattices (SLs) by taking advantage of the features of interband cascade infrared photodetectors (ICIPs). This method is more generally applicable, considers the parasitic shunt and series resistances found in practical devices, and can account for various transport mechanisms including Auger and Shockley-Read-Hall processes. The investigated ICIPs have cutoff wavelengths in the close vicinity of 4.3 μm at 300 K. The carrier lifetimes in these ICIPs at high temperatures (200–340 K) were extracted and found in the range of 8.5–167 ns, with values correlated with the material quality. The temperature dependence of the extracted carrier lifetime exhibited different characteristics from previously reported behavior obtained using other methods for T2SL detectors, especially at high temperatures.