AVS 46th International Symposium
    Surface Science Division Tuesday Sessions
       Session SS-TuP

Paper SS-TuP14
Surface Core Level Shift on GaN(0001) Surface

Tuesday, October 26, 1999, 5:30 pm, Room 4C

Session: Poster Session
Presenter: Y. Yang, Montana State University
Authors: Y. Yang, Montana State University
S.H. Xu, Montana State University
H. Cruguel, Montana State University
G.J. Lapeyre, Montana State University
H.J. Ho, TopoMetrix Co.
Correspondent: Click to Email
Synchrotron radiation photoelectron spectroscopy (SRPES) has been employed to investigate the electronic structure of clean wurzite GaN(0001) surface. The Ga 3d, N 1s and valence band emissions are measured by recording the energy distribution curves (EDC). A surface-shifted core level component is observed in the Ga 3d emission. It is located at 0.6 eV higher binding energy than the bulk component. The surface component is sensitive to atomic H adsorption. Experiment with deposition of ultra-thin Mg layer strongly support that it is attributed to the first layer Ga atoms. On the same sample, the surface core level shift of N 1s is identified at 1.0 eV lower binding energy side of the bulk component. The origin of the observed surface core level shifts will be discussed. Atomic-force-microscopy (AFM) image with line profiles are also acquired to determine the surface morphology.