Quantum Materials - 18

Abstract

For the development of solid-state molecular machinery, a direct focused He+ beam machining is presented to fabricate solid-state nano-disk [1-3] (Fig. 1(a)) at the surface of a graphene multilayer micro-flake deposited on an Au/Ti/sapphire surface [2,3]. At irradiation doses larger than 5×1017 ions/cm2 and with a beam size well below 1 nm, graphene disks down to 20 nm in diameter have been machined with for nano-disk down to 30 nm in diameter, a central hole for preparing the positioning of a rotation axle (Fig. 1(b)). The local heat generated by this irradiation is inducing a partial graphene amorphization, melting, and deformation, leading to a complete graphene nano-disk vaporization at doses larger than 5×1018 ions/cm2 [3]. A dry transfer printing technique followed by a graphene surface cleaning was used to transfer the nano-disks from its initial surface to a fresh and clean surface [3] (Fig. 1(c)). Atomic force microscope was recorded to follow the vaporization as a function of the He+ dose to confirm the graphene solid-state nano-disk fabrication limit to about 20 nm with this process. Ultra-high vacuum scanning tunneling microscope was used to characterize the change in the electronic state by the local irradiation.