Optical transitions in long-wavelength light-emitting diode heterostructures based on InAsSb

Subject of study. An n-InAs/InAs1-ySby/ p-InAsSbP light-emitting diode heterostructure with an indium antimonide molar fraction (y = 0.15) for a long-wavelength (over 4 mu m) region of the mid-infrared range and epitaxial n+-InAs/InAs1-ySby films (y = 0-0.16) is studied. Aim of study. The aim is to determine the nature of optical transitions in long-wavelength InAsSb-based light-emitting diode heterostructures aimed at extension of the range of their operation to the spectral region of wavelengths over 4 mu m as well as to decrease the temperature dependence of the wavelength of the heterostructures. Method. The heterostructures under study were grown by metal-organic vapor phase epitaxy, and the light-emitting diode chip was formed by standard photolithography and chemical etching. The optical properties of the resulting structures were studied by photo- and electroluminescence methods, the chemical composition of the films was studied by energy-dispersive X-ray spectroscopy on a scanning electron microscope, and the structural properties of the films were studied by X-ray diffractometry. Main results. It is shown that the structural and optical properties of InAs1-ySby epitaxial films are mainly determined by the indium antimonide content in the ternary solid solution. A significant effect of radiative transitions involving interface states at the "film-substrate" heterointerface, as well as indirect recombination transitions at a step-like type II InAsSb/InAsSbP heterojunction in the n-InAs/InAs0.85Sb0.15/ p-InAsSbP light-emitting diode heterostructure at temperatures below 150 K on the optical properties of the structures is demonstrated. It is shown that switching of the main channel of the radiative recombination of structures makes it possible to reduce the influence of temperature on their wavelength. Practical significance. The revealed effect of switching the main channel of radiative recombination with temperature determines the prospects for the manufacture of temperature-stable light-emitting diodes for the mid-infrared range. (c) 2023 Optica Publishing Group