Ion-implanted ~(32)S targets for astrophysics studies

摘要

The fabrication of isotopically pure 10.4 μg/cm~2 targets of ~(32)S by the implantation of 60-100 keV negative ions into a 61 μg/cm~2 pure ~(12)C thin foil is described. The process has been accomplished in rather shorter times than has been achieved previously by implanting the as-prepared carbon foil while still mounted on the underlying glass slide, thereby allowing for the use of much larger beam current intensities. The target has been assayed for absolute composition as a function of depth using Rutherford backscattering spec-trometry and excellent agreement between the measured and nominal ~(32)S fluences was observed. The implanted targets exhibit excellent stability with regard to subsequent 34.5 MeV proton beam irradiation.