Study of the critical angle of channeling of active metal ions through thin aluminum films

The spatial distributions of ions (K$^+$, Na$^+$) passed through thin polycrystalline and single-crystalline Al films with the thickness from 180 to 600 $\mathring{\mathrm{A}}$ and critical channeling angles have been studied. The ion energies have been varied within the range $E_0$ = 10–30 keV. It has been shown that an increase in the energy of the primary ion beam leads to a decrease in the width of the maxima of the angular distribution, which is associated with a decrease in the critical channeling angle $\psi_{cr}$. It has been found that the value $\psi_{cr}$ does not exceed 4–50 for axial channeling and 9–100 for planar channeling.