Development of indium arsenide/indium gallium antimonide superlattices for infrared detection

The development of an InAs/InGaSb superlattice is presented starting with the growth of single layers of InAs and GaSb. The growth of these compounds, in the presence of background of group V elements, was studied and optimized with help of reflection high energy electron diffraction (RHEED). The cross incorporation and the quality of the crystals were analyzed with secondary-ion mass spectroscopy (SIMS) and x-ray diffraction (XRD). The growth surfaces were evaluated with Auger electron spectroscopy (AES) and x-ray photoelectron spectroscopy. The single layer InAs/InGaSb heterostructures and their interfaces were examined with XPS and x-ray reflectivity measurements and shown to be atomically abrupt. The InAs/InGaSb band offset was determined to be 0.7 (eV). The superlattices quality was analyzed with XRD and transmission electron microscopy (TEM). The optical absorption in the infrared region was obtained through Fourier transform infrared spectroscopy.