Search

Identifying interfacial properties and discussing optical properties of antimony‐based type II superlattices are the key factors for developing high performance of infrared optoelectronic devices. Herein, the multi‐epitaxy‐layered structure of a mid‐wavelength‐responsive infrared detector with an InAs/InAsSb superlattice as an active area layer is grown and investigated. High‐resolution X‐ray diffraction, high‐resolution transmission electron microscopy, and the geometric phase analysis indicate epitaxial layers of high crystalline quality and small lattice mismatches. The electric field results obtained by differential phase contrast scanning transmission electron microscopy further confirm the sharp interface states and good periodic structure of the as‐grown samples. The photoluminescence spectrum shows that the photoluminescence signal center is 5.4 μm at 75 K, even at 320 K, the sample still maintains a photoluminescence signal of 6.2 μm. [ABSTRACT FROM AUTHOR]

Infrared optoelectronic devices based on type‐II superlattice structures of III–V semiconductor materials have progressed significantly during the past decades. Exploring and further expanding the material space is of great significance for the development of infrared applications. Herein, a superlattice structure based on InAs(Sb)/InxGa1−xAsySb1−y grown using a fractional monolayer alloy process to control the superlattice composition and structure is presented. High‐order satellite peaks with a narrow full width at half maximum (31 arcs) in the X‐ray diffraction patterns indicate the good crystal quality of the superlattices. Transmission electron microscopy (TEM) with energy‐dispersive spectroscopy (EDS) analysis validate the fractional monolayer alloy growth method. Photoluminescence measurements and k·p model calculations reveal the superior optical properties of the superlattice (sevenfold higher intensity than that of InAs/GaSb). In addition, the flexible control over the superlattice structure afforded by the method allows miniband engineering to cover the mid‐wavelength and long‐wavelength infrared regions. This work highlights the great potential of InAs(Sb)/InxGa1−xAsySb1−y superlattices in infrared optoelectronic devices. [ABSTRACT FROM AUTHOR]