Wafer scale compatibility and maturity of the proposed pre-treatment can enable fast adoption for the fabrication of graphene-based devices on large-diameter wafer scale. We demonstrate that the FDTS self-assembled monolayer (SAM) significantly improves nucleation of HfO 2 on graphene. We adapt an established process used for surface energy modification in the fabrication of micro-electro-mechanical systems (MEMS) structures and their cavities 19. In this work we investigate a pre-treatment of graphene with perfluorodecyltrichlorosilane (FDTS) prior to HfO 2 deposition on blanket Silicon 8 inch wafers as well as on pre-structured TiN films. These approaches significantly improve nucleation in ALD and CVD processes, however, they increase process complexity and are often not compatible with Si technology standards. Different seeding layers improving nucleation were investigated including low- k polymers 13, 14, thin metal films 15, 16, substrate induced seeding 17 or a pre-treatment with NF 3 18. The direct growth of dielectrics on graphene was reported with several methods such as chemical vapour deposition (CVD) 9, plasma-enhanced CVD 10 and atomic layer deposition (ALD) 11, but the deposition of conformal insulating layers usually requires formation of a seed layer due to the lack of dangling bonds on a defect-free surface of graphene 12. For these envisioned applications including field-effect transistors 2, 3, 4, graphene base transistors 5, 6, 7 and optoelectronic devices 8 thin conformal dielectric and semiconductor layers have to be grown on graphene. Due to its unique properties graphene is a potential material for use in next-generation micro- and nanoelectronics 1.
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