Determination of the sp3/sp2 ratio of a-C:H by XPS and XAES

X-ray photoelectron spectroscopy and X-ray excited Auger electron spectroscopy were used to determine some of the properties of diamond like amorphous carbon films deposited using saddle field glow discharge of methane. By applying the chemical shift technique and curve fitting technique to the Cls peak in the X-ray photoelectron spectrum of the film, we were able to determine the sp(3)/sp(2) bonding ratio of the films. The ratio from this method was in agreement (+/-1%) with that calculated from the X-ray excited Auger electron spectrum of the same film. The method was also applied to a-C:N films doped with different impurities (boron and phosphorus) in amounts varying from 1% to 20%. We found that the sp(3)/sp(2) ratio of the film was dependent on the deposition parameters and on types of impurities and their concentrations. (C) 1999 Published by Elsevier Science B.V. All rights reserved.