Regensburg 2010 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 34: Poster I: III-V Semiconductors
HL 34.29: Poster
Dienstag, 23. März 2010, 18:30–20:30, Poster D2
Morphology and atomic structure of InGaN(0001) surfaces — •Amelie Biermann1, Christian Friedrich1, Veit Hoffmann2, Norbert Esser3,1, Michael Kneissl1, and Patrick Vogt1 — 1TU Berlin, Institute of Solid State Physics EW6-1, Hardenbergstr. 36, 10623 Berlin, Germany — 2Ferdinand-Braun-Institut f. Hoechstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin, Germany — 3ISAS-Berlin, Albert-Einstein Str. 9, 12489 Berlin, Germany
Group III-nitrides offer a broad application spectrum in optoelectronic devices. Although the fabrication of high-quality devices requires the control of nanometer thick layers, there is only limited knowledge about the atomic structure of the surface. Here we present a study on the morphology and atomic structure of (0001) InxGa1−xN surfaces grown by MOVPE. Samples are prepared under UHV conditions by thermal annealing between 600∘C and 800∘C to achieve clean, decontaminated surfaces. Additionally thermally cracked ammonia and nitrogen plasma are used as nitrogen sources in order to vary surface stoichiometries and to prevent nitrogen depletion of the crystal. The chemical composition of the surface during preparation is determined by Auger Electron Spectroscopy. Clean (0001) InxGa1−xN surfaces were prepared at 760∘C revealing no surface carbon and low residual oxygen compounds. Depending on the surface preparation, surface structures showing different surface symmetries such as (1×1), (1+1/6) or (2×2) were obtained as determined by LEED. The chemical composition remains similar for all structures. In order to get further information STM measurements of the atomic structure are presented.