We demonstrate unambiguously that the well-known defect-related Y luminescence band at 1.476 eV in CdTe originates from the polar Te(g) glide dislocation segments. Crystallographically defined glide dislocation arrangements produced by local plastic deformation on (iii)Te surfaces using Vickers microindentation were characterized by temperature-dependent cathodoluminescence (CL) microscopy as well as CL and PL spectroscopy. The identification of the Te(g) dislocation was obtained by determining the surface polarity applying X-ray ddfraction and subsequently revealing the volume glide geometry observed by CL imaging after stepwise depth-etching of the ii it sample surface. From the spectral and recombination-kinetic properties of the dislocation-bound Y luminescence the model of radiative decay of dislocation-related excitons is supported. Particularly, we may conclude that they are bound to energy levels in the fundamental gap localized at the 90°Te(g) partial dislocations 1.

The distributions of polar dislocations appearing in surface and volume deformation zones of indentations on 111Cd, " 1 " 1 " 1Te and 110 surfaces of CdTe bulk crystals are studied. Distinct CL contrast properties proved in CdTe for A(g)-and B(g)-type dislocations are utilised to recognise Cd(g) and Te(g) dislocation segments in the deformation-induced defect configurations. The microscopic spatial glide geometries as caused by indenting the low-indexed surfaces are theoretically developed within the framework of an advanced h110i glide prism model. Comprehensive results gained by means of depth-resolved CL microscopy fully confirm the concept of 3D glide prism formation. The experimental findings give evidence for a coexistence of Cd(g) and Te(g) dislocations in tangential as well as tetrahedral deformation zones. From that, correlated propagation of polar dislocation segments during plastic flow has to be concluded.

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