Development of a pulsed, variable-energy positron beam for atomic scale defect studies

• Main Authors: Codding, C.L (Author), Greaves, R.G (Author), Jones, A.C.L (Author), Selim, F.A (Author)
• Format: Article
• Language: English
• Published: American Institute of Physics Inc. 2022
• Subjects: Atomic-scale defects; Defect study; Defects; Depth dependents; Electrons; Energy; Films; Metal dielectrics; Metal semiconductors; Nondestructive characterization; Nondestructive examination; Particle beams; Positron annihilation; Positron annihilation spectroscopy; Positron-beams; Pulsed positron beams; Single-atoms
• Online Access: View Fulltext in Publisher
• ISBN: 00346748 (ISSN)
• DOI: 10.1063/5.0077750

Positron annihilation spectroscopy provides a sensitive means of non-destructive characterization of materials, capable of probing single atom vacancies in solids with 10-7 sensitivity. We detail here the development of a magnetically guided, variable energy, pulsed positron beam designed to conduct depth-dependent defect studies in metals, semiconductors, and dielectrics, which will be the first of its kind in the United States. The design of the target stage provides capabilities for measurements during in situ annealing up to 800 °C and incorporates a new approach to minimize the background due to energetic backscattered positrons. The developed beam at Bowling Green State University provides a powerful tool for characterization of thin films, devices, and ion irradiated materials. © 2022 Author(s).