Effect of growth technological conditions on the heterointerface thickness in the InAs/GaSb strained-layer superlattices grown by MOCVD

Abstract

Abstract In this article, we investigated the effect of technological growth parameters by metal-organic chemical vapor deposition (MOCVD) method on the thickness of the transition layers, which affect the value of tensile strain in the structure, in the InAs/GaSb superlattice. We consider that the thickness of transition layers depends on the roughness of the growth surface and the technological conditions of growing single layers in the superlattice. At the first stage, we have determined the optimal annealing parameters for the minimization of the substrate roughness as T = 650 °C and t = 8 min, with a minimum value of 1.1 nm. At the second stage, studies were carried out on the effect of the sequence of elements and the delay time of reagent supply during the growth of InAs and GaSb layers on the quality of heterointerface. The stress analysis of the obtained structures was performed by reflectance anisotropy spectroscopy. It was shown that a superlattice becomes less tense with the increase in the number of pairs of alternating layers.