Progress on the development of interband cascade photodetectors

Abstract

The InAs/GaSb type-II superlattice (T2-SL) based interband cascade (IC) photodetectors are emerging as a promising candidate for high performance infrared (IR) detectors, particularly for high operating temperature applications. In this paper, we present our latest progress on the development of high performance IC photodetectors in both mid-and longwave-IR. Our results show significant improvement in both the electrical and optical performance for the IC detectors. The mid-IR detectors show zero-bias operation, with external quantum efficiency as high as 11%. The dark current is 1.75 nA/cm 2 at 120 K and -10mV, which shows over 5 times improvement over our previous best results. The Johnson-limited D* of the mid-IR detector is around 1.20×10 11 Jones at 200 K, showing more than 10 times improvement over a wide temperature range. These mid-IR IC detectors have obtained background limited operation up to 210 K. Progress in longwave-IR IC detectors is also presented, which also demonstrates excellent electrical performance.