Direct fabrication of integrated 3D epitaxial functional transition metal oxide nanostructures using extremely small hollow nanopillar nano-imprint metal masks

A novel nanofabrication technique is developed for functional oxides. Combining nano-imprint lithography, sidewall-etching and sidewall-deposition processes enables us to prepare Mo hollow nanopillar masks with 100 and 60 nm window sizes, which is smaller than the original nano-imprint mold size of 250 nm. Using this Mo nanomask, extremely small epitaxial ferromagnetic oxide (Fe(2.5)Mn(0.5)O(4)) nanostructures can be directly grown on sapphire substrates at the deposition temperature of 350 °C in a pulsed laser deposition (PLD) process.

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