Search results for "Binary collision approximation"

Low-energy primary knock on atom damage distributions near MeV proton beams focused to nanometre dimensions

2007

Abstract In this preliminary study, the spatial extent of the defects introduced in Si by a normally incident 1 MeV H + nanobeam was investigated using a hybrid approach. First, the standard SRIM code was employed to calculate the angular and energy distributions of Primary Knock-on Atoms (PKA) using the Binary Collision Approximation (BCA). The long mean free path and the kinematics of scattering in a screened Coulomb potential resulted in an anisotropic PKA distribution that was mainly directed perpendicular to the primary ion trajectories. The PKA energy E dependence was close to 1/ E n with 1.5  n The results revealed that the low energy PKA’s resulted in localised damaged regions with …