Regensburg 2013 – wissenschaftliches Programm
MM 15.57: Poster
Montag, 11. März 2013, 18:00–20:00, Poster E
Resonant Photoemission at the O1s threshold to characterize In2O3 single crystals — •Jörg Haeberle1, Matthias Richter1, Dieter Schmeißer1, Zbigniew Galazka2, and Christoph Janowitz3 — 1BTU Cottbus, Applied Physics, Konrad-Wachsmann-Allee 17, 03046 Cottbus, Germany — 2Leibniz-Insitut für Kristallzüchtung, Max-Born-Straße 2, 12489 Berlin, Germany — 3Humboldt-Universität zu Berlin, Institut für Physik, Newtonstraße 15, 12489 Berlin Germany
We report on spectroscopic investigations on In2O3 single crystals. We focus on the detailed analysis of the O1s resonance profile by resonant photoelectron spectroscopy (resPES). From these we analyze the electronic structure and assign the O2p- and In5sp-state to build the valence band and the conduction band in different contributions, respectively. This is deduced from constant final statespectra on the O-KLL-Auger along the O K-edge and In M4,5-edge and a comparison to the corresponding X-ray absorption spectroscopy data. We also identify several types of defects. A broad band of oxygen derived defects is identified in the valence band and extends throughout the gap. Small polarons are attributed to cause an anti-resonance in the constant initial states around the O1s threshold. In addition, an Auger decay separated by the O-KLL is present at O-K resonance and indicates the existence of localized charge transfer states which involves In5sp states. Finally, we are able to distinguish two different oxygen species from the resPES data. One corresponds to theintrinsic In2O3 structure and the other is a non-corresponding species.