In our recent paper @NanoResearch (Springer Nature), we report about the use of atomic layer deposition (ALD) to grow Co thin films, with thickness from several tens down to few nanometers on top of a granular topological insulator (TI) Sb₂Te₃ film. The Co growth occurs along the [00l] direction following the underlying rhombohedric structure of Sb₂Te₃, while it crystallizes in the cubic phase along the [111] direction when deposited on Pt. With this work, we demonstrate that in case of deposition of crystalline materials, the ALD surface selectivity and conformality can be extended to the definition of local epitaxy, where in-plane ordering of the crystal structure and mosaicity of the developed crystallized grains are dictated by the underlying substrate. A highly sharp and chemically-pure Co/Sb₂Te₃ interface is evidenced, which is promising for the application of this growth process for spintronics.

You can now publicly surf&share the full-text view-only version of our paper here.
 

This research has been done in the framework of the "MP1402-Hooking together the European research in atomic layer deposition (HERALD)" COST action, and the Horizon 2020 project SKYTOP “Skyrmion-Topological Insulator and Weyl Semimetal Technology” (FETPROACT-2018-01, n. 824123).