A new empirical model of the 2-dimensional ionisation probability ϕ(ρr, ρz) described by an analytical function

Abstract For quantitative electron probe microanalysis matrix effects have to be considered. Conventional matrix correction procedures in use today assume a homogeneous composition for the bulk sample (known as ZAF correction) or heterogeneity only in depth for thin films ( ϕ ( ρz ) models). But when heterogeneity is expected in lateral directions, only Monte Carlo and deterministic simulations could be used for accurate matrix correction. These simulations are computationally expensive and slow. In this work, we introduce a novel analytical model for the multi-dimensional ionisation probability distribution ϕ ( ρr, ρz ) for a material bombarded with electrons, which could be used for fast matrix correction as an alternative to simulations. By fitting the model onto ionisation probability distributions generated by Monte Carlo simulations, we show that our model can adequately describe the simulated distributions.