Interaction of protons with a relief surface at comparable sizes of microroughnesses and mean projective path in a material

A method of statistic test on computer has been employed to study the reflection of protons with initial energy E0=1000 eV from a copper target with a one-dimensional regular relief on the surface for the case of comparable values of a mean projective path of ions in the material (Rp=120 A) and the height of equilateral ridges forming the relief h=100 A. The incidence angle of protons on the target θ0 and the inclination angle of the ridge faces φb varied from 0 to 89 deg. It is found that at incidence angles θ0 > ∼ 55 deg starting from a certain value of φb the probability of the protons reflection is practically independent of the geometry of the roughnesses. In this case the RN values for the relief surface coincide with the values of the reflection coefficient for even surface with the density linearly increasing in the surface layer of thikness h from zero to the density of a massive sample, i.e. varying according to the law preset by a change of an averaged density of relief surface