Structural and optical properties of InAs/InAsSb superlattices grown by metal organic chemical vapor deposition for mid-wavelength infrared photodetectors

InAs/InAsSb superlattices were grown on (001) GaSb substrates by metal organic chemical vapor deposition for potential applications as mid-infrared optoelectronic devices. X-ray diffraction, transmission electron microscopy, photoluminescence emission and spectral photoconductivity were used to characterize the grown structures. Generally, photoluminescence emission measurements of InAs/InAsSb superlattices were performed over the temperature range from 11 K to 300 K. The Varshni and Bose-Einstein parameters were determined. Low-temperature photoluminescence measurements showed peaks at 3-5 mu m, while photoconductance results showed strong spectral response up to room temperature, when the photoresponse onset was extended to 5.5 mu m. The photoluminescence emission band covers the CO2 absorption peak making it suitable for application in CO2 detection. (C) 2016 Elsevier B.V. All rights reserved.