Quantification of Ag/Ni Auger electron spectroscopy depth profiles upon preferential sputtering with non-stationary roughness

The measured Auger electron spectroscopy (AES) depth profiles of the as-deposited Ag/Ni multilayers demonstrate a strong preferential sputtering effect. In the framework of the Mixing-Roughness-Information depth (MRI) model, the influence of preferential sputtering on the “measured” depth profile is quantitatively evaluated. The mass conservation upon AES preferential sputtering is verified and applied to obtain the true layer thickness from the measured depth profiling data (i.e. intensity or composition as a function of sputtering time). Meanwhile the influences of preferential sputtering and non-stationary roughness effects on the depth resolution are also quantitatively evaluated. Based on the developed model, the measured AES depth profiles of the Ag/Ni multilayers as-deposited and annealed at different temperatures are fitted and the interdiffusion coefficients are obtained accordingly.