LabAdviser/314/Microscopy 314-307/SEM/Nova/Transmission Kikuchi diffraction: Difference between revisions
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This happens because thin films are kinetically frozen unstable structures as a consequence of their formation far from equilibrium. Since the driving force for dewetting is the minimization of the total energy of the free surfaces of the film and substrate and of the film-substrate interface, the total free energy associated with the interfaces of a film is reduced if the film agglomerates to form islands. Solid-state dewetting occurs at temperatures well below the melting temperature of the film, so that the material remains in the solid state throughout the process. Since the rate of dewetting is higher in thinner films, the temperature at which dewetting occurs decreases with decreasing film thickness. | This happens because thin films are kinetically frozen unstable structures as a consequence of their formation far from equilibrium. Since the driving force for dewetting is the minimization of the total energy of the free surfaces of the film and substrate and of the film-substrate interface, the total free energy associated with the interfaces of a film is reduced if the film agglomerates to form islands. Solid-state dewetting occurs at temperatures well below the melting temperature of the film, so that the material remains in the solid state throughout the process. Since the rate of dewetting is higher in thinner films, the temperature at which dewetting occurs decreases with decreasing film thickness. | ||
== | == Nanostructure evolution during heating == | ||
A preliminary investigation of the Au �lm at room temperature revealed a | |||
bimodal nanostructure, with the presence of small grains with size in the | |||
range of 30 nm and large grains with size in the 150 nm range. The latter | |||
ones showed a strong [111] out-of-plane texture (Fig. 3.11) . | |||