Tailoring Fast Directional Mass Transport of Nano-Confined Ag-Cu Alloys upon Heating: Effect of the AlN Barrier Thickness.

This study addresses the phase stability and atomic mobility of Ag-Cu nano-alloys confined by AlN in a nanomultilayered configuration during thermal treatment. To this end, nanomultilayers (NMLs) with a fixed Ag-Cu nanolayer thickness of 8 nm and a AlN barrier nanolayer with variable thickness of 4, 8, or 10 nm were deposited by magnetron sputtering on sapphire substrates and subsequently isothermally annealed for 5 or 20 min in air in the range of 200-500 °C. The microstructure of the as-deposited and heat-treated NMLs was analyzed by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and energy dispersive spectroscopy.

Modeling of Interface and Internal Disorder Applied to XRD Analysis of Ag-Based Nano-Multilayers.

Multilayered structures are a promising route to tailor electronic, magnetic, optical, and/or mechanical properties and durability of functional materials. Sputter deposition at room temperature, being an out-of-equilibrium process, introduces structural defects and confers to these nanosystems an intrinsic thermodynamical instability. As-deposited materials exhibit a large amount of internal atomic displacements within each constituent block as well as severe interface roughness between different layers.