Berlin 2008 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 9: ZnO: Preparation and characterization I
HL 9.13: Vortrag
Montag, 25. Februar 2008, 18:15–18:30, EW 201
Chemical nature of N incorporated into ZnO during epitaxial film growth — •Patrick Hoffmann, Christian Pettenkofer, and Stefan Andres — Hahn-Meitner-Institut, Glienicker Straße 100, 14109 Berlin
ZnO is a wide band gap semiconductor (gap=3.4eV) which is unintentionally n doped by nature. In the last years it has been shown that ZnO can be p doped by incorporation of nitrogen. Nevertheless, some puzzling results suggest that just incorporation of nitrogen not simply leads to p doped ZnO. Investigations have shown that nitrogen can replace oxygen (NO, p doping), but can also be incorporated as molecular N2 ([N2]O, n doping), and can be bonded to oxygen. Therefore, this investigation concentrates on the chemical nature of the incorporated nitrogen during ZnO growth. The ZnO films are grown by metal-organic MBE (MOMBE) on sapphire substrate (r plane), while nitrogen is supplied by an ion source. Additionally, a mass filter between the ion source and the sample gives the opportunity to minimise the influence of the neutrals (e.g. N2), and to select certain ions and ion fractions (e.g. N2+, N+). The obtained films were investigated by means of XPS and NEXAFS. A comparison of the differently prepared films will be given.