Structural Evolution of Gas-Phase Coinage Metal Clusters in Thiolate Self-Assembled Monolayers on Au

• Published in: Journal of physical chemistry. C 2012-10, Vol.116 (42), p.22602-22607
• Main Authors: Costelle, Leila, Räisänen, Minna T, Joyce, Jennifer T, Silien, Christophe, Johansson, Leena-Sisko, Campbell, Joseph M, Räisänen, Jyrki
• Format: Article
• Language: English
• Subjects: Applied sciences; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Electronics; Exact sciences and technology; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Materials science; Methods of nanofabrication; Molecular electronics, nanoelectronics; Physics; Self-assembly; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp307148p

Metallization of organic surfaces is important especially for applications in molecular electronics. It can be realized by different means, one promising albeit less studied method being gas-phase deposition of metal clusters. Here, we report on the interactions of gas-phase Cu, Ag, and Au clusters with n-dodecanethiolate self-assembled monolayers (SAMs) on Au substrate. The morphology and composition of the deposited clusters and their impact on the interface structure of the SAM/Au substrate were investigated using scanning tunneling microscopy. The chemical and physical interactions between the clusters and thiolates were characterized using X-ray photoelectron spectroscopy. The Au clusters are found to penetrate through the monolayer as a whole and partially retain their spherical geometry, whereas atom-by-atom diffusion and/or defect-mediated penetration are proposed for the Cu and Ag clusters.