Growth and surface structure analysis of a new SiON single layer on SiC(0001)

A new silicon oxynitride layer was formed on a 6H-SiC(0001) surface by a nitrogen oxide treatment. The atomic structure of this single layer on the SiC(0001) substrate was determined by means of low-energy electron diffraction (LEED) analysis. The surface layer has a ( 3 × 3 ) R30° periodicity. Its LEED I(E) spectra are different from those of the previously reported silicon oxynitride layer which has a Si4O5N3 composition [Phys. Rev. Lett. 98 (2007) 136105]. The best-fit structure has a single layer of Si2ON3 composition terminated by O bridges. The Si–N layer of the determined structure has the same structure as that in the Si4O5N3 surface. The obtained Si2O3 structure would be useful for preparing an ideal SiC–insulator interfaces with a low interfacial density of states.