Electronic stopping powers derived from range measurements for ions at low velocity

Abstract

Electronic stopping cross sections for 19F + in Pb 1− x Sn x Te and 19F +, 40Ar +, 75As +, 79Br + and 132Xe + in silicon were obtained by range measurements. Depth profiles of F in Pb 1− x Sn x and Si were measured by 19F(p, αγ) 16O resonance nuclear reaction and those of Ar, As, Br and Xe were determined by RBS. In order to obtain the true range distribution from the measured NRA excitation curves or RBS spectra, a deconvolution program was developed using a reference function, the Edgeworth distribution function, and parameter optimization process. By forcing a fit between the experimentally determined projected range and that calculated with the range statistics program the total stopping power was obtained. After subtracting the nuclear stopping power the electronic stopping power was derived. The electronic stopping power can be described by a four-parameter formula.