Gamma-radiation effect on donor and acceptor states in CdTe and CdTe:Cl

• Published in: Journal of alloys and compounds 2004-05, Vol.371 (1-2), p.142-145
• Main Authors: Krylyuk, S.G, Korbutyak, D.V, Kryuchenko, Yu.V, Kupchak, I.M, Vakhnyak, N.D
• Format: Article
• Language: English
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electron-phonon interactions; Exact sciences and technology; Ii-vi semiconductors; Impurities in semiconductors; Luminescence; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Photoluminescence; Physics; Semiconductors
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2003.06.015

The evolution of photoluminescence (PL) spectra with increasing γ-irradiation dose was monitored for undoped and Cl-doped CdTe crystals. The emission intensities and the Huang-Rhys factors for different PL lines were determined as a function of the exposure dose. In irradiated CdTe:Cl, an irradiation-induced enhancement of the electron-phonon coupling for the A-center PL was attributed to decreasing concentration of the donor–acceptor pairs responsible for this band. Gamma-irradiation of undoped CdTe at a dose larger than 10kGy resulted in quenching of the A-center PL at 1.4eV, the donor–acceptor line in the edge luminescence at 1.55eV, as well as emission of the donor-bound excitons. Observed peculiarities are explained by a decrease of concentration of isolated donors, presumably through the creation of complexes with intrinsic defects generated by γ-rays.