Enhanced electrical transport through wrinkles in turbostratic graphene films

TL;DR

This study investigates how wrinkles in large-area turbostratic graphene films significantly enhance local electrical conductivity, suggesting potential for improved nano-electronic device performance through controlled wrinkle engineering.

Contribution

It provides the first detailed local electrical property measurements of wrinkled turbostratic graphene, revealing that wrinkles greatly increase electrical transport.

Findings

Electrical current is several orders of magnitude higher on wrinkles.

Wrinkles can be engineered to improve electronic device performance.

Enhanced conductivity is localized at the wrinkles.

Abstract

Formation of wrinkles is a common phenomenon in the large area growth of two dimensional layered materials on metallic substrates. Wrinkles can significantly affect the working of 2D materials based large scale electronic devices and therefore, it is of utmost importance to investigate local electrical properties of such wrinkled/folded structures on 2D materials. Here, we report local conductivity measurements by conducting atomic force microscopy (CAFM) and surface potential mapping by Kelvin Probe Force microscopy (KPFM) on large area wrinkled turbostratic graphene films grown on nickel foils. We show that the electrical transport current is several orders of magnitude higher on the wrinkles than that on the flat regions of the graphene films. Therefore, our results suggest that controlled engineering of such wrinkles on graphene may facilitate development of superior graphene-based nano-electronic devices where transport of high current through narrow channels are desired.