Electron Paramagnetic Resonance and Photoluminescence Studies of Impurities in CdTe

摘要

CdTe single crystals from different sources have been examined to detect the presence of impurities which may be detrimental to applications in the fabrication of infrared detectors. Distinctive EPR signals from various donor impurities, including substitutional paramagnetic Fe, were found in several samples. A photoluminescence transition at 1.1 eV was also seen in these crystals and the amplitudes of the photoluminescence signals and the Fe EPR signals are strongly correlated. Elemental analysis of the samples indicates that EPR and PL are able to detect Fe concentrations of less than 0.1 ppm. Keywords: Electron paramagnetic resonance, Impurities in compound semiconductors, Defects in compound semiconductors, Iron, Cadmium tellurides. (MJM)