AFM studies of metallic and organic nanosized structures ion beam sputtered onto functionalised surfaces

Abstract

The growth of submonolayer metallic or molecular nanostructures via ion beam sputtering onto reconstructed semiconductor surfaces followed by in situ scanning probe imaging of the formed nanostructures provides an interesting basis for future development of new molecular multifunctional nanoarchitectured materials for various applications. The observed growth modes, structure and topology of pentacene, which is one of the most important candidates in the field of organic thin film electronic molecules, and Au metallic nanostructures deposited in the submonolayer regime onto reconstructed InP (0 0 1) surface, are discussed. During the initial stages of growth, a uniaxial diffusion channel dominates, and long pentacene molecular chains self-organise parallel to the [110] crystallographic direction on the InP surface. The study is performed by in situ non-contact atomic force microscopy (AFM) investigations with atomic resolution. It is shown that self-assembling of molecular structures onto flat terraces is dependent on the flatness and orientation of the terraces reconstructed onto the semiconductor surface. Moreover, it is possible to create functional molecular nanoarchitectures by nanomanipulation of single molecules with the AFM tip. This procedure may have large impact for technological applications such as organic thin film transistors and molecular nanowires.