S. Brunner1, W. Puff1, B. Logar1, P. Mascher2, A. G. Balogh3, H. Baumann4
1 Institute fuer Kernphysik, Technische Universitaet Graz, Petersgasse 16, Graz, Austria,
2 Centre for Electrophotonic Materials and Devices, Department of Engineering Physics, McMaster University, Hamilton, Ont. L8S 4L7, Canada,
3 FB Materialwissenschaft, Technische Hochschule Darmstadt, Darmstadt, Deutschland,
4 Institut fuer Kernphysik, J.W. Goethe Universitaet Frankfurt am Main, Deutschland
In this contribution, we present a study aimed at investigated basic properties of radiation induced defects in ZnO and ZnS. Positron annihilation experiments (both lifetime and Doppler-broadening measurements) were performed on polycrystalline samples. For ZnO it was found that both electron and proton irradiation caused significant changes in the positron annihilation characteristics and several annealing stages were observed, related to the annealing of variously sized vacancy complexes. The lifetime in defected, proton irradiated polycrystalline ZnS samples, grown by chemical vapor deposition, indicates the formation of large defect complexes. The annealing of proton irradiated ZnS in air at temperatures between 650ºC and 750ºC leads to significant oxidation and transformation into ZnO.