Depth information in Auger electron spectroscopy

Two different methods giving non destructive depth information in Auger Electron Spectroscopy (AES) are described, (i) The first one is based on the Auger ratio PB (ratio of the Auger peak to the background at the same energy). In the case of a binary alloy XY, and as soon as the Auger electron mean free paths of the two elements are sufficiently different, it is possible to obtain a depth information by plotting (PB)x versus (PB)y (ii) The second one is more general and uses the ratio of the Auger tail height (T) to the Auger peak height (P). This ratio (TP) is independent of the concentration of the element. It is only dependent on its depth distribution. Both methods are applied to the experimental example of a silver deposit on a Si(111) surface.