X-ray diffuse scattering by microdefects in nonstoichiometric InSb single crystals

InSb single crystals with different antimony contents (50, 51, and 52 at. %, respectively) grown from melts have been studied by the X-ray diffuse-scattering method. Different amounts of large and small microdefects with opposite strength signs were observed in the crystals of all the compositions depending on their nonstoichiometry. It is assumed that large microdefects are formed in the one-phase region at high temperatures, whereas smaller microdefects are formed due to the decomposition of solid solutions. The density of small microdefects is minimal for a crystal whose composition is close to stoichiometric.