Investigation of Lead Iodide for X-Ray Detection

• Antragsteller: Privatdozent Dr. Andreas Nikolaus Danilewsky
• Fachliche Zuordnung: Physikalische Chemie von Festkörpern und Oberflächen, Materialcharakterisierung
• Förderung: Förderung von 2008 bis 2011
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 60659482

This application in the field of applied materials science continues the successful collaboration between the Institute of Chemical Technology in Prague and Institute of Photonics and Electronics (IPE, Academy of Sciences of the Czech Republic) and the Crystallography, Institute of Geosciences, University of Freiburg, Germany. The major aim of the actual project renewal remains unchanged: the synthesis, refinement, and growth of single crystals of PbI2 and the optimisation of electronic properties in view of X-ray detectors operating at higher temperatures up to 130°C. The modification of electro-optical properties will be studied in dependence of adding dopants like Ag, Au, Ge, Sn, Zn etc., respectively. To find the correlations between growth procedure, type and concentration of admixtures, and the detector relevant physical properties an extensive characterisation is essential with respect to the materials stoichiometry, purity, polytypes, crystal defects, as well as lifetime and mobility of charge carriers. In addition to the Bridgman-Stockbarger method, where the seeding behaviour is difficult, for the first time the Czochralski technique was successfully applied to grow PbI2 from PbI2 seeds. The new and very promising feature is the growth of crystals along a defined direction like [1120], i. e. parallel to the (0001) layers, allowing an improved preparation of crystal slices for characterisation. This approach is supposed to be persued intensely.

• DFG-Verfahren: Sachbeihilfen
• Internationaler Bezug: Tschechische Republik
• Beteiligte Personen: Professor Dr. Arne Cröll; Dr. Jaroslav Maixner; Dr. Marie Matuchová