COMPLEMENTARY SCATTERED AND RECOILED ION DATA FROM TOF-E HEAVY-ION ELASTIC RECOIL DETECTION ANALYSIS

The advantage of Time of Flight and Energy (ToF-E) Heavy Ion Elastic R ecoil Detection Analysis (HIERDA) over Rutherford Backscattering (RBS) analysis is its mass and energy dispersive capabilities. RES cannot s eparate signals from very heavy elements; the limitation is a result o f physical principles of the two-body collision process. The mass reso lution of ToF-E HIERDA deteriorates for very heavy elements; the limit ation is related to the poor energy resolution of Si detectors for hea vy ions. Very high ion energies improve the energy resolution and cons equently the mass resolution of HIERDA, but significantly lower the cr oss section. Usually the energy spectra from ToF-E HIERDA data are use d to extract depth profiles. In this work, the benefits of using the t ime spectra of both the recoiled and the scattered ions are discussed. The advantages are: (i) improved depth resolution by using the time s pectra, and (ii) although the energy of very heavy recoils decreases w ith increasing mass, the energies of scattered ions increase. Time and energy projections of spectra, which have overlapping signals provide complementary data for analysis. (C) 1998 Elsevier Science B.V.