Eur. Phys. J. B 46, 457-461 (2005)
https://doi.org/10.1140/epjb/e2005-00274-4

Si/SiO core shell clusters probed by Raman spectroscopy

¹ Dipartimento di Fisica e Astronomia, Università di Catania; MATIS - Istituto Nazionale di Fisica della Materia, Via Santa Sofia 64, 95123 Catania, Italy
² Dipartimento di Scienze Chimiche, Università di Catania; MATIS - Istituto Nazionale di Fisica della Materia, Viale Andrea Doria 6, 95123 Catania, Italy
³ IMM, Consiglio Nazionale delle Ricerche, Catania, Italy
⁴ Elettra, Sincrotrone Trieste, Trieste, Italy

Corresponding author: ^a Giuseppe.Faraci@ct.infn.it

Received: 23 February 2005
Revised: 23 May 2005
Published online: 7 September 2005

Abstract

Using a pulsed microplasma source, clusters were produced through the ablation of a Si cathode and successive supersonic expansion. The Si cluster beam was deposited onto different substrates and the partial oxidation of the cluster surface avoided the growth of large agglomerates, preserving their nanocrystalline morphology. Micro-Raman spectroscopy was used for an accurate size diagnosis of the deposited nanoparticles. The size of the Si dots ranges between 2 and about 15 nm. The Si dots appear to have a Si oxide shell, as confirmed also by structural and compositional analysis through transmission electron microscopy and atomic force microscopy. Double Raman peaks were attributed to small Si agglomerates having a thin substoichiometric Si-O interface.