LOCAL-STRUCTURE OF DIAMOND FILMS - AUGER AND EELFS INVESTIGATION

A series of diamond films deposited on Si(100) wafers by chemical vapo ur deposition (CVD) from methane/hydrogen mixtures has been analyzed u sing different electron spectroscopies. Auger electron spectra allowed evaluation of the filled density of states of the films in terms of p i and sigma valence bands. They have been correlated to the graphite c ontent of diamond films by comparison with the Auger spectrum taken fr om a sample of highly oriented pyrolitic graphite (HOPG). The pi and sigma features detected in the K-edge electron energy loss spectra ha ve been used to evaluate the sp(2)/sp(3) ratio. The extended energy lo ss fine structure (EELFS) spectra provide information on the local str uctural order of the deposits. The Fourier transforms of the EELFS ind icate a sizable decrease of the interplanar distances of the carbon at oms in diamond films compared to the HOPG sample.