title: Dealloying of platinum-aluminum thin films: dynamics of pattern formation.
abstract: The application of focused ion beam (FIB) nanotomography and Rutherford backscattering spectroscopy (RBS) to dealloyed platinum-aluminum thin films allows for an in-depth analysis of the dominating physical mechanisms of nanoporosity formation during the dealloying process. The porosity formation due to the dissolution of the less noble aluminum in the alloy is treated as result of a reaction-diffusion system. The RBS and FIB analysis yields that the porosity evolution has to be regarded as superposition of two independent processes, a linearly propagating diffusion front with a uniform speed and a slower dissolution process in regions which have already been passed by the diffusion front. The experimentally observed front evolution is captured by the Fisher-Kolmogorov-Petrovskii-Piskounov (FKPP). The slower dissolution is represented by a zero-order rate law which causes a gradual porosity in the thin film.
authors.affiliation: Nonmetallic Inorganic Materials, ETH Zurich, Zurich, Switzerland. henning.galinski@mat.ethz.ch
authors.forename: Henning
authors.initials: H
authors.lastname: Galinski
authors.forename: Thomas
authors.initials: T
authors.lastname: Ryll
authors.forename: Lukas
authors.initials: L
authors.lastname: Schlagenhauf
authors.forename: Felix
authors.initials: F
authors.lastname: Rechberger
authors.forename: Sun
authors.initials: S
authors.lastname: Ying
authors.forename: Ludwig J
authors.initials: LJ
authors.lastname: Gauckler
authors.forename: Flavio C F
authors.initials: FC
authors.lastname: Mornaghini
authors.forename: Yasmina
authors.initials: Y
authors.lastname: Ries
authors.forename: Ralph
authors.initials: R
authors.lastname: Spolenak
authors.forename: Max
authors.initials: M
authors.lastname: Döbeli