Experimental determination of the energy dependence of electron inelastic mean free path in silicon oxide and silicon nitride

The energy dependence of the electron inelastic mean free path, λ(E), in silicon oxide and silicon nitride is experimentally determined via Auger electron spectroscopy according to Auger signal attenuation with varying film thickness. Silicon-oxide- and silicon-nitride films are formed on different metal substrates by means of plasma-enhanced chemical vapor deposition. Analysis of the results and their comparison with theoretical data indicate that, in the chosen material, variations in the electron mean free path versus their energy are estimated more reliably by means of experiments than through the use of universal theoretical curves. It appears that the results obtained in this work can help in the more accurate determination of the width and location of interfaces in multilayer structures.