Preferential sputtering in quantitative sputter depth profiling of multi-element thin films

Abstract Preferential sputtering plays an important role in the quantification of measured depth profiles. The distortion of the measured depth profile as compared to the original one has to be evaluated upon preferential sputtering in depth profiling. In the framework of the mixing-roughness-information depth (MRI) model, the influences of preferential sputtering on the depth profile of multi-element thin films are quantitatively evaluated as demonstrated for a layered structure of three elements with different sputtering rates and subsequent interfaces as A/BC/A. Moreover, the mass conservation upon Auger electron spectroscopy/X-ray photoelectron spectroscopy depth profiling of multi-element structure is discussed with respect to the preferential effect. Finally, as an example, the measured glow discharge optical emission spectroscope depth profiling data of 60x(3.0 nm Mo/0.3 nm B4C/3.7 nm Si)/Si(111) multilayer structure are quantitatively evaluated using the extended MRI model.