ELECTRONICS OF MOLECULAR NANOCLUSTERS

Abstract

The molecular nanoclusters proved to be very promising objects for applications in electronics not only because they have absolutely identical chemical structure and allow for bottom to top approach in constructing new electronic devices, but also for the possibility to design and create great variety of such clusters with specific properties. The formation and deposition of mixed Langmuir monolayers composed of inert amphiphile molecular matrix and guest ligand-stabilized metal-core nanoclusters are described. This approach allowed to obtain the ordered stable reproducible planar monolayer and multilayer nanocluster nanostructures on solid substrates. The use of novel polymeric Langmuir monolayers formed by amphiphilic polyelectrolytes and nanoclusters resulted in fabrication of ultimately thin monomolecular nanoscale-ordered stable planar polymeric nanocomposite films. The morphology and electron transport in fabricated nanostructures were studied experimentally using AFM and STM. The effects of single electron tunneling at room temperature through molecular cluster object containing finite number of localized states were theoretically investigated taking into account electron–electron Coulomb interaction. It is shown that tunnel current-bias voltage characteristic of such tunnel junction is characterized by a number of staircase steps equal to the number of cluster's eigenlevels, however the fronts of each steps are asymptotically linear with finite inclination. The analytically obtained current–voltage characteristics are in agreement with experimental results for electron tunneling through molecular nanoclusters at room temperatures.