Normal incidence, long-wave infrared InAs/In/sub 0.15/Ga/sub 0.85/As dots-in-well detectors grown by molecular beam epitaxy

In the past few years, there has been active research on studying the performance characteristics of quantum dot infrared detectors (QDIPs) for mid-wave infrared (MWIR, 3-5 /spl mu/m) and long-wave infrared (LWIR, 8-12 /spl mu/m) applications ranging from night vision cameras and battle recognition systems to chemical spectroscopy and remote sensing. Present day photon detectors in this wavelength range need to be cooled to liquid nitrogen temperature or below to reduce the deleterious effects arising due to the large thermionic emission. Quantum dot detectors have already demonstrated normal incidence MWIR operation at temperatures as high as 150K/sup 1/ and the reported results in the literature from several groups show significant promise for this technology/sup 2/. Nevertheless the responsivity and specific detectivity of QDIPs is significantly lower than those observed in mercury cadmium telluride (MCT) detectors.