Characterisation of organic thin films by atomic force microscopy - Application of force vs. Distance analysis and other modes

Many important technologies depend on applications of organic thin films. The properties of surfaces and interfaces of film/substrate structures are of particular importance. It is becoming apparent that the atomic force microscope (AFM) has much to offer, especially when in situ non-destructive characterization is required. The ability of AFM to provide high resolution topographical images is well-developed. Recent studies have shown that force vs. distance (F-d) analysis can map at high spatial resolution mechanical properties of organic films, as well as those of the substrate. The same mode will also provide quantitative information about adhesive interactions. A formalism has been developed, based on a series combination of linearly compliant elements, from which film thickness and elastic moduli can be inferred from the detailed structure of F-d curves. The methodology is illustrated for the native lipid layer on wool fibre and for the multilayer structure of magnetic tapes.