Doping induced structural changes in CuInS2 thin films and the effects on optical and electrical properties

The systematical study of the admixture of small amounts of group‐II elements (<1 at%) with Raman and photoluminescence spectroscopy reveal an increase in the Raman response of the cation‐anion vibration modes accompanied with the generation of a new broad emission band at 1.35 eV in the PL spectra of the chalcopyrite system Cu–In–S. Intensity dependent PL measurements indicate that this emission band is strongly influenced by a high degree of compensation in contrast to the commonly found donor‐acceptor pair recombination in undoped CuInS2 samples. From temperature dependent conductivity measurements an increased concentration of acceptors and donors in doped CuInS2 thin films is found. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)