Solid State Conversion: Microstructuring of Crystalline Al₂O₃ (Sapphire) by Annealing of Patterned Aluminium Films

Abstract:

Surface structuring on the nano/micro level is important for a huge range of areas. A critical bottle neck for many industrial applications is upscaling; that is to say it must be possible to do the structuring in a comparatively simple and inexpensive manner. However, this is a challenge for many industrially important materials, including sapphire. A few years ago, solid state conversion was introduced as a relatively simply nanoscale structuring method for sapphire. Here we show that the method, by careful choice of parameters, can be extended to work also on the micron scale. We show that a microstructured aluminium film deposited on a Al₂O₃ (0001) surface is converted into a crystalline Al₂O₃ surface, when thermally annealed in air, using optimized parameters.

• Periodical: Key Engineering Materials (Volume 875)
• Pages: 29-34
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.875.29
• Online since: February 2021
• Authors: Naureen Akhtar*, Simen Hjellvik Askeland, Bodil Holst
• Keywords: Annealing, Nanostructures, Sapphire, Surface Modification

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