Defect structure of high-resistance CdTe:Cl single crystals and MoOx/CdTe:Cl/MoOx heterostructures according to the data of high-resolution X-ray diffractometry

Abstract

Clorine doped CdTe single crystals (CdTe:Cl) were grown by the traveling heater method. MoO x /CdTe:Cl/MoO x films were deposited using the reactive magnetron sputtering technique. The defect structure of the obtained single crystals and heterostructures was investigated using high-resolution X-ray diffractometry. The optimized models of dislocation systems in the CdTe:Cl single crystals were constructed based on the Thompson tetrahedron. The distribution of the intensity of diffracted X-rays as a function of reciprocal space coordinates and rocking curves was analyzed using the kinematic theory of X-ray scattering in real crystals. The experimental and theoretically predicted values of the helical dislocation densities in the CdTe:Cl and MoO x /CdTe:Cl crystals with perfect and mosaic structures were compared. Two-fold increase in the dislocation concentration in the MoO x /CdTe:Cl heterostructures as a result of compression deformations of the CdTe:Cl crystal lattice was found. The ~0.1 μm thick transition deformed layer at the boundary between the MoO x film and CdTe:Cl single crystal significantly affects the electrical and spectroscopic properties of the obtained systems as the materials for γ-radiation detection.