A round robin characterisation of the thickness and composition of thin to ultra-thin AlNO films

A round robin characterisation of the thickness and composition of thin to ultra-thin AlNO films was organised. Thirteen participant groups used various ion beam analysis (IBA) techniques to determine quantitatively the thickness, areal density and concentration of aluminium, nitrogen and oxygen in films with thicknesses ranging nominally from 1 to 100 nm. Most of the ratios reported are not statistically different from the reference values, and only very seldom are large deviations observed. It was not possible to identify a given technique or a group of techniques as being more reliable for analysing the ultra-thin samples. Unexpected deviations in some results reflect a need for further measurements of fundamental quantities, namely cross-sections and stopping powers in energy ranges useful for IBA. Furthermore, precise measurements of beam fluence and detector solid angle would lead to improvements in the accuracy of some of the quantities reported, particularly areal densities.