Production and characterization of thin, self-supporting Si foils for use as targets in radioactive beam experiments

摘要

Development of thin, self-supporting silicon foils (both natural and isotopically-enriched) for use as targets in reaction studies with radioactive beams is detailed. Foils with a thickness of ~220 μg/cm~2 were produced using vapor deposition and were floated onto aluminum frames with 10-15 mm diameter holes. During their production, the foil thickness was measured using a quartz crystal monitor. Subsequently, the foil thickness was characterized by a particle energy loss measurements and Rutherford backscattering (RBS). These measurements demonstrated that the thickness could be determined to within a 0.5% uncertainty. The elemental purity of the foils was assessed using RBS and X-ray photoelectron spectroscopy. This analysis demonstrated that the foils have 87%-90% silicon abundance.