QUANTIFICATION OF BERYLLIUM IN THIN-FILMS USING PROTON BACKSCATTERING

The strong resonance in the H-1-Be-9 backscattering cross section near H-1 laboratory energy 2525 keV has been used to determine Be-9 areal densities in thin films with accuracies of about 6%. We report measure d cross sections (for a 170.5-degrees laboratory backscattering angle) for H-1 on Be-9 for H-1 energies from 2400 to 2700 keV. The areal den sities of the self-supporting Be foils used for the H-1-Be-9 measureme nts were determined from He-4-Be-9 backscattering measurements. We als o report measured cross sections for 170.5-degrees backscattering of H e-4 by Be-9 for He-4 laboratory energies of 500 to 4200 keV. Results o f channeling measurements in epitaxial Be films on crystalline substra tes are also discussed.