https://doi.org/10.1140/epjd/e2014-40811-6
Regular Article
Strong perturbation effects in heavy ion induced electronic sputtering of lithium fluoride
1 Centre de Recherche sur les Ions, les Matériaux et la Photonique (CEA-CNRS-ENSICAEN-Université de Caen-Basse Normandie UCBN), CIMAP-CIRIL-GANIL, BP 5133, Boulevard Henri Becquerel, 14070 Caen Cedex 05, France
2 Physics Department, Universidade Federal de Santa Catarina, 88000 Florianópolis, Brazil
3 Physics Department, Pontifícia Universidade Católica do Rio de Janeiro PUC, Rua Marquês de São Vicente 225, Gávea, 22453-900 Rio de Janeiro, Brazil
a
e-mail: rothard@ganil.fr
Received: 18 December 2013
Received in final form: 11 April 2014
Published online: 3 July 2014
Electronic sputtering of lithium fluoride by swift heavy ions was studied as a function of electronic energy loss (dE/dx)e. The single crystal targets were irradiated with swift heavy ion beams (166ZP692; 46EP/MP (MeV/u) 611). This allowed varying the deposited energy by a factor of 20 (1.86dE/dx (keV/nm) 632). The sputtered secondary ions were measured from well controlled LiF targets without surface contaminations, by means of the time-of-flight technique (TOF-SIMS). The mass spectrum reveals an important contribution of clusters (over single ions), which increases with (dE/dx)e. Another observation for the strongest perturbation at high dE/dx (>8 keV/nm) is that the secondary ion yields saturate: Y(dE/dx) = constant. In contrast, at lower dE/dx (<8 keV/nm) for weaker perturbation, the yield Y scales with (dE/dx)2. This quadratic increase would rather point towards a thermal evaporation-like mechanism leading to electronic sputtering, however, the origin of the yield saturation remains an open finding.
Key words: Clusters and Nanostructures
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2014
