Future Trends in Microelectronics

2.9

Structure and Electron Transport in Irradiated Monolayer Graphene

I. Shlimak, A.V. Butenko, E. Zion, V. Richter, Yu. Kaganovskii, L. Wolfson, A. Sharoni, A. Haran, D. Naveh, E. Kogan and M. Kaveh

Department of Physics and Faculty of Engineering, Jack and Pearl Institute of Advanced Technology, Bar Ilan University, 52900 Ramat Gan, Israel

1 Introduction

Disordered graphene has attracted the attention of many researchers.^1–3 Mainly, this is due to the possibility of obtaining a high-resistance state of graphene films, which is of interest for application in electronics. Experimentally, the disorder is achieved in various ways: by oxidation,⁴ hydrogenation,⁵ chemical doping,⁶ and irradiation by different ions with different energies.^7–11 In this chapter, we discuss ion bombardment as a way of gradually inducing disorder in monolayer graphene.

2 Samples

The initial specimens were purchased from the Graphenea company, who grew monolayer graphene by chemical vapor deposition (CVD) on a copper catalyst and used a wet transfer process to move it to a 300 nm SiO₂/Si substrate. The typical specimen size was 5 × 5 mm. Graphene films of such a large area are not monocrystalline but rather polycrystalline with an average microcrystal size of up to 10 µm.

On one of these specimens, gold electrical contacts were deposited directly on the graphene surface through a metallic mask (reference sample 0). On the other 5 × 5 mm specimens, many small devices of 200 × 200 µm area were prepared ...