Vacancy related defect profiles in MeV cluster-ion irradiated silicon

• Published in: Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms Beam interactions with materials and atoms, 1995, Vol.106 (1), p.233-236
• Main Authors: Hallén, A., Håkansson, P., Keskitalo, N., Olsson, J., Brunelle, A., Della-Negra, S., Le Beyec, Y.
• Format: Article
• Language: English
• Subjects: Atomic and Molecular Clusters; Physics
• ISSN: 0168-583X; 1872-9584; 1872-9584; 0168-583X
• DOI: 10.1016/0168-583X(95)00709-1

Silicon samples have been irradiated with cluster ions, 16.2 MeV Au 4 and 23 MeV C 60, from the Orsay tandem accelerator in France. After the irradiation, Schottky diodes are formed and the samples are studied with deep level transient spectroscopy. Majority carrier spectra of bombarded n-type silicon are dominated by the single charge state of the divacancy ( E C − E T = 0.42 eV). Measured depth distributions of the divacancy suggest that the peak of elastic energy deposition appears at the same depth for Au 4 ions as for monoatomic gold ions with one fourth of the energy. For C 60 clusters the measured peak is closer to the surface than the peak of the vacancy distribution calculated with TRIM. Comparison with vacancy distributions also shows that the deep tail of the divacancy defect distribution is extended to greater depths. The interpretation is that divacancies are created not only by direct collisions, but also by diffusion and pairing of two single vacancies.