Titolo | Thermal behavior of indium nanoclusters in ion-implanted silica |
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Tipo di pubblicazione | Articolo su Rivista peer-reviewed |
Anno di Pubblicazione | 2004 |
Autori | Tagliente, M.A., Mattei G., Tapfer Leander, M. Antisari Vittori, and Mazzoldi P. |
Rivista | Physical Review B - Condensed Matter and Materials Physics |
Volume | 70 |
Paginazione | 075418-1-075418-8 |
ISSN | 01631829 |
Parole chiave | article, cooling, heating, Indium, ion, mathematical analysis, Melting point, particle size, precipitation, pressure, Silicon Dioxide, temperature related phenomena, thermodynamics, Transmission electron microscopy, X ray diffraction |
Abstract | Fused silica substrates were implanted with 2 × 1017 In2+/cm2 ions at 320 keV. Indium crystalline nanoclusters with an average size of about 15-20 nm were found in the as-implanted samples. The thermal behavior of the nanoclusters was studied by performing heating-cooling cycles in vacuum and by using in-situ techniques based on glancing-incidence x-ray diffraction and transmission electron microscopy. The precipitates showed both superheating and supercooling. Moreover, no evidence of clusters growth or reorientation during the thermal cycle was found. A detailed study of the heating sequence showed that the melting temperature of the Indium precipitates depended on their size, i.e., the smallest particles melt first and at a temperature which is about 7 K below the bulk melting point, while the largest ones were superheated until about 13 K above it. Moreover, a remarkable stability of the In cluster well above their melting temperature (up to about 980 K) was evidenced by in-situ transmission electron microscopy analysis. From a thermodynamic point of view, the experimental results were explained by considering two effects acting on the clusters: the thermodynamic size effect and the pressure of the silica matrix. |
Note | cited By 18 |
URL | https://www.scopus.com/inward/record.uri?eid=2-s2.0-19544380894&doi=10.1103%2fPhysRevB.70.075418&partnerID=40&md5=499e3a74ea1ca581f6c0266218c229e4 |
DOI | 10.1103/PhysRevB.70.075418 |
Citation Key | Tagliente2004 |