J. Phys. III France
Volume 7, Numéro 7, July 1997
Page(s) 1505 - 1514
DOI: 10.1051/jp3:1997203
J. Phys. III France 7 (1997) 1505-1514

Localization of Y Luminescence at Glide Dislocations in Cadmium Telluride

S. Hildebrandt, H. Uniewski, J. Schreiber and H.S. Leipner

Martin-Luther-Universität, Fachbereich Physik, Friedemann-Bach-Platz 6, 06108 Halle (Saale), Germany

(Received 3 October 1996, revised 23 December 1996 accepted 17 March 1997)

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 ( $\overline{1}\,\overline{1}\,\overline{1}$)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 diffraction and subsequently revealing the volume glide geometry observed by CL imaging after stepwise depth-etching of the ( $\overline{1}\,\overline{1}\,\overline{1}$) 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.

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