A study of the relationship between spatial and angular coordinates of axially channeled MeV protons

Monte Carlo channeling simulations for 3 MeV protons which are transmitted close to the [011] axis of a silicon layer up to 200 nm thick are presented. The emergent angular intensity at different incident tilt angles and layer thicknesses is related to the spatial distribution of the channeled protons across the [011] unit cell. The transition between a channeling regime where the angular intensity distribution is dominated by 'rainbow' channeling, and a regime which is characterised by a 'doughnut' distribution is studied for different tilt angles. (C) 1999 Elsevier Science B.V. All rights reserved