Vitaly Babenko1 Ruizhi Wang1 Ye Fan1 Vlad-Petru Veigang-Radulescu1 Oliver Burton1 Jack Alexander-Webber1 Robert Weatherup2 Stephan Hofmann1

1, Cambridge University, Cambridge, , United Kingdom
2, Diamond Light Source, The University of Manchester, Didcot, Oxfordshire, United Kingdom

Utilisation of hexagonal boron nitride (h-BN) in applications requires further advancements in the production, processing, integration methods and also their cost reduction. We focus here on catalytic chemical vapour deposition (CVD) and discuss two very different catalysts for monolayer h-BN growth, iron and platinum, examples of a high and low precursor solubility transition metals. For Fe, we systematically explore the role of bulk dissolved species, and find that a simple pre-growth step enables us to tailor a scalable CVD process to give mm-sized h-BN domains,[1] among the largest reported to date. For Pt, we developed sequential step growth to enable independent control of h-BN nucleation and domain expansion to also give large (> 0.5 mm) h-BN domains and continuous films.[2] We show that targeted h-BN transfer methods are required for the different catalysts or even tweaked to the processing of the catalyst, whereby we develop a moisture oxidation and acid release method for the iron and a dry peeling approach for platinum. The utilisation of h-BN with graphene is demonstrated as an encapsulating layer for integration with common ALD dielectrics and in FET devices.[1] Additionally, we demonstrate the use of monolayer CVD h-BN as an active material for room temperature single photon emission.[3], [4]

[1] Babenko et al, submitted (2019).
[2] Wang et al. ACS Nano 13, 2114 (2019).
[3] Comtet, J. et al., Nano Lett. 19, 4, 2516 (2019)
[4] Stern, H. L. et al. ACS Nano 13, 4538 (2019).