Characterization of deposited Si-clusters by studying their chemical reactivity

Deposited Si-monomers and Si-tetramers on HOPG and amorphous carbon surfaces are studied using XPS. Simonomers on amorphous carbon show identical structures to those of the Si carbides and/or silicon oxides. In contrast, deposited Si-tetramers are inert towards carbide and oxide formation. Chemical properties of deposited Si-tetramers are identical to those of the free Si-tetramer clusters in the gas phase, implying that the deposited Si-tetramers should experience only minor changes from their original geometric and electronic structures of the free Si-tetramer clusters. We demonstrate that investigations on chemical activities of deposited magic clusters are useful to figure out, if the original cluster structures remain uncharged or not upon deposition. (C) 2004 Elsevier B.V. All rights reserved.