The deposition of dielectric materials on graphene is one of the bottlenecks for unlocking the potential of graphene in electronic applications. In this paper we demonstrate the plasma enhanced atomic layer deposition of 10 nm thin high quality Al2O3 on graphene using a monolayer of hBN as protection layer. Raman spectroscopy was performed to analyze possible structural changes of the graphene lattice caused by the plasma deposition. The results show that a monolayer of hBN in combination with an optimized deposition process can effectively protect graphene from damage, while significant damage was observed without an hBN layer. Electrical characterization of double gated graphene field effect devices confirms that the graphene did not degrade during the plasma deposition of Al2O3. The leakage current densities were consistently below 1 nA/mm for electric fields across the insulators of up to 8 MV/cm, with irreversible breakdown happening above. Such breakdown electric fields are typical for Al2O3 and can be seen as an indicator for high quality dielectric films.
@article{arxiv.2208.11601,
title = {Plasma-enhanced atomic layer deposition of Al$_2$O$_3$ on graphene using monolayer hBN as interfacial layer},
author = {Barbara Canto and Martin Otto and Michael J. Powell and Vitaliy Babenko and Aileen O Mahony and Harm Knoops and Ravi S. Sundaram and Stephan Hofmann and Max C. Lemme and Daniel Neumaier},
journal= {arXiv preprint arXiv:2208.11601},
year = {2022}
}