Among different II-VI compounds, cadmium telluride attracts much attention owing to a wide spectrum of its technological applications. Irradiation of CdTe with high-absorbed laser pulses may be effectively used to alter parameters of a thin sub-surface layer of the crystal while the characteristics of the bulk remain unchanged. However, correct interpretation of laser irradiation effects is complicated by generation, redistribution and interaction of different types of defects and impurity-defect complexes. These processes are not fully understood up to now.
In this contribution, results on laser irradiation of CdTe:Cl crystals are reported. The samples were irradiated with a single pulse of a ruby laser at power densities of 2.0 - 3.0 J/cm².
Selective etching of the irradiated samples revealed a huge increase in dislocation density (up to 10⁸ cm^-2) in the sub-surface layer with sharp edge between this layer and the bulk. Measurements of photoluminescence (PL) spectra also showed substantial changes in the PL properties of the irradiated samples. First of all, intensities of the so-called W line (around 1.586 eV) connected with excitons localized at the A-centers and the 1.4 eV band are significantly enhanced because of an increase in A-centers concentration. Appearance of new PL lines is assigned to generation of shallow defects whose nature is discussed. Influence of subsequent thermal annealing of the irradiated samples are explored as well.

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/1826 must be provided.

1. Hydrogen passivation of electrically active defects in CdTe created by the bromine-methanol etching
2. (Cd,Hg)Te Defect Structure and its Magnetoresistive Properties, Modified by Pulse Laser Irradiation