3D structure evolution using metastable atomic layer deposition based on planar silver templates
in: Applied Surface Science (2020)
This work investigates the influence of different process parameters on the evolution of complex 3D silica/silver structures using metastable atomic layer deposition (MS-ALD). MSALD is a recently developed method for the fabrication of 3D structures based on selfassembly side reactions accompanying the cyclic formation and decomposition of metastable Ag oxide in which silver (Ag) nanoparticles serve as templates. In this work, planar Ag films are used as templates instead of Ag nanoparticles, with the influence of diverse process parameters being analyzed in detail. We found that the initial thickness of the Ag film has a significant effect on the resulting structures, leading to a variety of different structures from small pillar-like structures to complex nanowire architectures. We also found that – the MSALD process being characterized by a substrate-enhanced growth behavior where the growth per cycle gradually decreases with a growing number of cycles –, even at the very high number of 900 cycles, we still work in the transient regime. Nevertheless, MS-ALD might be promising deposition technique for energy harvesting or catalytic applications due to the possibility to achieve high surface-to-volume ratios and of using large scale-depositable planar silver films.