Thin SolidFilms, 109 (1983) 159-167 zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIH PREPARATION AND CHARACTERIZATION zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJI 159 ON THE USE OF THE AUGER TECHNIQUE FOR QUANTITATIVE ANALYSIS OF OVERLAYERS ROSSELLA M EM EO, FRANC0 CICCACCI, CARLO MARIANI AND STEFANO OSSICINI Dipartimento di Fisica, Universitd della Calabria, 87036 Arcavacata zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPON di Rende. Cosenra (Italy) (Received M arch 8,1983; accepted June 6,1983) Within a simple model we discuss here the results of a calculation which contributes to the reliability of the use of the Auger technique as a quantitative tool. We consider the adsorption of foreign species on a substrate for three different cases: the submonolayer region, uniform thin film growth and island formation. We show that in all the cases it is possible to find a relation involving the peak-to-peak height ratios of the adsorbate and substrate Auger lines that gives the following information about the system: absolute coverage, thickness of the film and characteristics of the island growth respectively for the above cases. For the submonolayer region, only one Auger spectrum is necessary to evaluate the coverage. In the other cases it is also possible to establish whether the growth proceeds layer by layer or by island formation. 1. INTRODUCTION Auger electron spectroscopy has found wide application in surface analysis’*‘. The first derivative of the signal (the conventional Auger spectrum) is routinely used in laboratories as a standard method to check the cleanliness of solid surfaces and to identify possible surface contaminants. It also provides a tool to monitor the adsorption of foreign species and overlayer growth on a substrate3. Qualitative analysis can be easily accomplished by comparing the experimental spectra with the standard published tables that give the relationship between Auger electron energies and atomic numbers. In general this procedure results in rapid and unambiguous interpretation of the spectra. For bulk alloys the use of the peak- to-peak height measurement from the first derivative Auger spectra yields quite accurate values for the concentration, provided that the sensitivity factor character- istic of each element is taken into account. In other cases, e.g. an overlayer grown on a substrate, the situation is complicated by the presence of a concentration gradient in the uppermost layers and, except for particular cases, there is not a standard method to relate the intensity of the Auger peaks to the surface concentration. This is indeed the common situation in the study of chemisorption, interface formation and thin film deposition. Our work is an attempt to overcome these difficulties. For this reason we 004~6090/83/%3.00 0 Elsevier Sequoia/Printed in The Netherlands