Ranges ofN+15ions in ten metals measured by (p, αγ) resonance broadening

Abstract

Concentration distributions of ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}_{}^{+}{}_{}{}^{}$ ions implanted in Al, Ti, Ni, Cu, Zn, Mo, Ag, Ta, W, and Au substrates have been measured in the energy range of 20-100 keV by means of the broadening of the $E_p=429\mathrm{}$ keV resonance yield curve from the ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}(p, \alpha \gamma ){}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ reaction. The implanted-atom concentration was always less than 0.1%. The proton stopping powers needed in the derivation of the ranges were determined experimentally. Proton energy straggling was included in the ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$ range analysis. In comparing the distribution predictions of the Lindhard-Scharff-Schiøtt (LSS) theory with the experimental results the fraction of ${}_{}{}^{15}{}_{}{}^{}\mathrm{N}$ reflections was taken into account with the Monte Carlo calculations. The consistency between theoretical and experimental range values is within 20% limits. Except for the Al and Ti cases, the mean ranges in these polycrystalline targets were found to be larger than those predicted by the LSS theory as being valid for amorphous targets. The merits of the method used, the effects of possíble diffusion, and relevance of the range values to Doppler-shift attenuation measurements are discussed.