Hole mobility in organic ultrathin film field-effect transistors is studied as a function of the coverage. For layered sexithienyl films, the charge carrier mobility rapidly increases with increasing coverage and saturates at a coverage of about two monolayers. This shows that the first two molecular layers next to the dielectric interface dominate the charge transport. A quantitative analysis of spatial correlations shows that the second layer is crucial, as it provides efficient percolation pathways for carriers generated in both the first and the second layers. The upper layers do not actively contribute either because their domains are smaller than the ones in the second layer or because the carrier density is negligible.

Dewetting is a spontaneous phenomenon where a thin film on a surface ruptures into an ensemble of separated objects, like droplets, stripes, and pillars. Spatial correlations with characteristic distance and object size emerge spontaneously across the whole dewetted area, leading to regular motifs with long-range order. Characteristic length scales depend on film thickness, which is a convenient and robust technological parameter. Dewetting is therefore an attractive paradigm for organizing a material into structures of well-defined micro- or nanometre-size, precisely positioned on a surface, thus avoiding lithographical processes. This tutorial review introduces the reader to the physical–chemical basis of dewetting, shows how the dewetting process can be applied to different functional materials with relevance in technological applications, and highlights the possible strategies to control the length scales of the dewetting process.

Novel strategies forinformation storage technology rely upon multistable systems that can be controllably switched between different configurations of comparable free energy. Multistability is present in many molecular and supramolecular systems through a variety of properties (conformations, redox and spin states, shape and dimensionality) that can be influenced by external stimuli. In the solid state, however, it is difficult to amplify the effects of molecular switching to higher length scales in order to relay the response to the outside world