Design and Potential Applications of Stochastically Nanostructured Metal Films

Due to their unique morphology, stochastically nanostructured metal films can exhibit a broad range of unusual physical, chemical, and quantum mechanical properties. Physically, structures can vary from fields of spherical aggregates to reefs of coral-like branching structures that form through diffusion limited aggregation.  Such nanostructured thin metal films may be condensed on a cooled substrate from thermally evaporated metals in the presence of a buffer gas. The simplicity and low costs of this preparation technique are particularly appealing from the point of view of ultimate scalability.  Our immediate objective is to determine the effects of varying metallic composition, temperature, pressure, and gas species on properties of the film. Films will be  characterized using SEM, transport measurements, and various optical and chemical probes. Measured properties will guide the search for novel applications. Potential applications include the identification of individual molecules through surface enhanced Raman spectroscopy, higher infrared absorptivity for single photon detectors, and the developments of solid catalysts with higher surface area to mass ratios. The disordered structure of the films may also result in novel low-temperature quantum transport properties. Our ultimate goal is to correlate depositional parameters with structure, and structure with properties, in order to enable the design of nanostructured thin metal films suitable for various applications in science and industry.