Channeling maps for Si ions in Si: Assessing the binary collision approximation

Abstract Simulations based on the binary collision approximation (BCA) are in principle less accurate than molecular dynamics (MD) simulations. In this work, we present a comprehensive comparison between BCA and MD for Si ions impinging on a (0 0 1)-Si surface by comparing “channeling maps”, i.e., projected ranges of the ions as a function of incidence direction in a representative part of the angular space. We find quantitative differences to develop as the energy decreases below ∼ 100 eV, but find qualitative agreement down to ∼ 10 eV. Moreover, the quality of the BCA channeling maps depends on the implementation of the BCA, which is explained in terms of double-hits and missed collisions.