Thin film analysis by low-energy ion scattering by use of TRBS simulations

Low energy ion scattering (LEIS) spectra of thin film structures are analyzed by Monte-Carlo simulations using the TRBS code. Although originally developed for the analysis of Rutherford backscattering (RBS) spectra, the TRBS code can be used to obtain valid simulations of LEIS data, which take place at energies several orders of magnitude lower than in RBS, when the appropriate adjustments are made. Experimental results from a set of Al2O3/HfO2 thin film stacks are shown, and their analysis by means of TRBS simulations is demonstrated. The authors show that the simulations yield valuable insights, especially in the case of ultrathin films <1 nm, where traditional evaluation methods using empirical models can be misleading.