In this project we will utilize an integrated ALD+PVD platform available in the PI’s lab, the SC-1 (SwissCluster-1,), which is the only lab-scale system of its kind in the U.S. capable of combining these two deposition methods without the need to ever break vacuum or move substrates during deposition. We will design a nanolaminate architecture where nanocrystalline Al and Ti alloys (deposited using physical vapor deposition (PVD)) are intercalated between stable interfaces of Å-thick atomic layer deposition (ALD) layers. Such an arrangement has a number of distinctive features for adapting to LEO environments. For example, while metals with nanocrystalline grain sizes are known to have exceptionally high strengths, their stability is uncertain, since grain growth can be triggered by small temperature increases with drastic consequences for their properties. In our innovative solution, the metal layer is confined into nanocrystalline PVD thin films. We’ll exploit ALD to bound these metal sublayers using barrier layers that are made of few atomic layers of oxides, in order to prevent grain coarsening. Additionally, we will tune the architecture to contain interfaces (both between as well as within individual layers) with controlled sink efficiencies, thus designing a coating material in which nearly all radiation-induced defects are annihilated.
