Regensburg 2007 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 46: Poster 2
HL 46.31: Poster
Donnerstag, 29. März 2007, 15:00–17:30, Poster A
Observation of InN(0001) surface and bulk properties during oxidation — •C. Friedrich1, T. Schenk1, M. Drago1, W. Braun2, W. Richter1,4, N. Esser1,3, P. Vogt1, and M. Kneissl1 — 1TU Berlin, Institute of Solid State Physics, Hardenbergstr. 36, 10623 Berlin, Germany — 2BESSY GmbH, Albert-Einstein-Str. 15, 12489 Berlin, Germany — 3ISAS Berlin, Albert-Einstein-Str. 9, 12489 Berlin, Germany — 4Universita Tor Vergata, Via della Ricera Scientifica 1, 00133 Rome, Italy
The determination of the InN electronic bandgap is still not completely solved but is most likely related to quality and purity of the investigated material. The incorporation of oxygen in sputtered InN films was already reported, but the influence on the crystal, optical and electronic properties remains unclear. Here we present a soft x-ray photoemission (SXPS) study of the surface and bulk deoxidation of MOVPE grown InN(0001)/sapphire through thermal annealing. SXPS reveals composition and binding configuration within the surface layers which gives rise to clear C1s and O1s core-level contributions. Thermal annealing at 300°C is sufficient to remove most of these components. Only a stable O1s oxide contribution could not be removed even at 460°C. These results are compared to ellipsometric measurements in different gaseous environments. We could identify surface oxidation occurring in humid ambient below 150°C as well as bulk oxidation around 450°C in dry air. These two different oxidation effects are in good agreement with the SXPS measurements. These results can be used for the optimization of InN surface morphology.