Growth and Performance of Yttrium Oxide as an Ideal High-kappa Gate Dielectric for Carbon-Based Electronics

High-quality yttrium oxide (Y2O3) is investigated as an ideal high-kappa gate dielectric for carbon-based electronics through a simple and cheap process. Utilizing the excellent wetting behavior of yttrium on sp(2) carbon framework, ultrathin (about few nm) and uniform Y2O3 layers have been directly grown on the surfaces of carbon nanotube (CNT) and graphene without using noncovalent functionalization layers or introducing large structural distortion and damage. A top-gate CNT field-effect transistor (FET) adopting 5 nm Y2O3 layer as its top-gate dielectric shows excellent device characteristics, including an ideal subthreshold swing of 60 mV/decade (up to the theoretical limit of an ideal PET at room temperature). The high electrical quality Y2O3 dielectric layer has also been integrated into a graphene FET as its top-gate dielectric with a capacitance of up to 1200 nF/cm(2), showing an improvement on the gate efficiency and on state transconductance of over 100 Limes when compared with that of its back-gate counterpart.