Temperature-assisted high-energy-per-atom argon cluster SIMS of layered hybrid nanomaterials

Abstract

Time of Flight Secondary Ion Mass Spectrometry is a powerful technique for the characterization of various materials. Depth profiling in the dual beam mode enables the acquisition of information about the three-dimensional composition of a sample. In this context, the selection of the most appropriate sputter conditions is of critical importance in order to ensure the reliability of the results obtained. Despite advancements, challenges persist in finding a suitable sputter source to perform depth profiling on hybrid nanomaterials (based on the mixing of pure organic and inorganic compounds), primarily due to the different sputtering conditions required for the inorganic and the organic components. In this work, we present an approach that employs a high-energy-per-atom argon cluster sputter source to perform depth profiling of a model hybrid sample consisting of molybdenum oxide and N,N′-Di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine. The findings demonstrated that decreasing the cluster size while maintaining a high kinetic energy of the beam allowed to increase the sputtering yield for the inorganic moiety, while preserving the molecular information of the organic counterpart. Moreover, we demonstrated that damage accumulation and ion beam mixing processes can be successfully attenuated by decreasing the sample temperature during depth profiling.