SURFACE MICROANALYSIS WITH A VARIABLE INFORMATION DEPTH STUDY OF SILICON-OXIDE ON SILICON

We investigate the property of variable information depth of Core-Electron-Energy Loss Spectroscopy (CEELS) in the reflection mode and of Auger Electron Spectroscopy (AES) in order to analyse non-destructively thin silicon oxide films on silicon. In CEELS in the reflection mode the information depth can be varied simply by varying the primary beam energy E(o). The obtained variation ranges from 0 to 50 angstrom. In Auger Electron Spectroscopy the variation of the information depth is significant only if the energy E(o) is varied in the range E(ijk) < E(o) < 2E(ijk) (E(ijk) = energy of the Auger electrons). In this paper we report measurements with a variable information depth on thin silicon oxide films grown on silicon by thermal oxidation. The possibilities and limits of the two techniques in this application will be discussed.