Structural characterization of H plasma-doped ZnO single crystals by positron annihilation spectroscopies
Structural characterization of H plasma-doped ZnO single crystals by positron annihilation spectroscopies
Anwand, W.; Brauer, G.; Cowan, T. E.; Grambole, D.; Skorupa, W.; Cizek, J.; Kuriplach, J.; Prochazka, I.; Egger, W.; Sperr, P.
Abstract
Nominally undoped, hydrothermally grown ZnO single crystals have been investigated after doping in remote H plasma. Characterizations have been made by positron annihilation (slow positron implantation spectroscopy, lifetime, coincidence Doppler broadening), temperature-dependent Hall and photoluminescence measurements. The H content before and after the doping has been determined using nuclear reaction analysis. In addition, changes of the polished surface of the crystals have been monitored by atomic force microscopy.
H plasma doping produced a metallic conducting near-surface layer. It is discussed if this is due to an increased H and zinc incorporation into pre-existing zinc vacancy H complexes, as this also could explain the occurrence of a second positron lifetime component in the volume of the crystals, from which a bulk positron lifetime of (153 +/- 2) ps for ZnO is derived in very good agreement with previous experiments and theoretical calculations.
Keywords: zinc oxide; point defects; positron annihilation; H; nuclear reaction analysis; H plasma; atomic force microscopy; Hall effect; photoluminescence
Beteiligte Forschungsanlagen
- P-ELBE
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Physica Status Solidi (A) 207(2010), 2415-2425
DOI: 10.1002/pssa.200925609
Cited 11 times in Scopus
Permalink: https://www.hzdr.de/publications/Publ-12970