Deposition of High-QualityHfO2on Graphene and the Effect of Remote Oxide Phonon Scattering

Abstract

We demonstrate atomic layer deposition of high-quality dielectric ${\mathrm{HfO}}_{2}$ films on graphene and determine the magnitude of remote oxide surface phonon scattering in dual-oxide structures. The carrier mobility in these ${\mathrm{HfO}}_{2}$-covered graphene samples reaches $20\text{ }000\text{ }\text{ }{\mathrm{cm}}^{2}/\mathrm{V}\text{ }\mathrm{s}$ at low temperature. Distinct contributions to the resistivity from surface optical phonons in the ${\mathrm{SiO}}_{2}$ substrate and the ${\mathrm{HfO}}_{2}$ overlayer are isolated. At 300 K, surface phonon modes of the ${\mathrm{HfO}}_{2}$ film centered at 54 meV limit the mobility to approximately $20\text{ }000\text{ }\text{ }{\mathrm{cm}}^{2}/\mathrm{V}\text{ }\mathrm{s}$.