Recent trends in 8-14 µm type-II superlattice infrared detectors

Type-II superlattices (T2SLs) hold enormous potential for next-generation, 8 – 14μm long-wavelength infrared (LWIR) detectors for use at high operating temperature (HOT). The inherit flexibility of the material system has enabled the incorporation of unipolar barriers to eliminate generation-recombination currents and enhance device performance. In addition to suppressed Auger recombination and tunneling currents, this has led to sustained research interest in this material system over the past several decades. For these reasons they are theoretically predicted to outperform the current state-of-the-art Mercury Cadmium Telluride (MCT) detectors. This review provides an overview of LWIR T2SL detectors and highlights some recent developments towards HOT applications. Recent studies on the minority carrier lifetime and diffusion length of T2SLs are examined to appraise the extent to which they limit the performance of HOT LWIR T2SL detectors. Strategies for mitigating these limitations are also explicated.