Abstract
Surface and interface structures of an ultrathin silicon nitride film grown epitaxially on the Si(111) surface are investigated by core-level and valence-band photoelectron spectroscopy using synchrotron radiation. The Si photoelectron spectra reveal a characteristic series of components for the Si species not only in stoichiometric but also in the intermediate nitridation states with one or three nitrogen nearest neighbors. The Si core-level shifts for the and components are determined to be 0.64, 2.21, and 2.74 eV, respectively. In sharp contrast to the well-known case, no trace of the species is observed, indicating an atomically abrupt and defect-free interface in accordance with a recent interface model of In addition, the origin of the characteristic N spectra and a strong surface-state emission observed in the valence-band spectra are discussed.
- Received 8 July 2002
DOI:https://doi.org/10.1103/PhysRevB.67.035304
©2003 American Physical Society