Preparation of few-layer graphene by annealing Ni film with low carbon content deposited by direct current magnetron sputtering

• Published in: Vacuum 2024-09, Vol.227, p.113421, Article 113421
• Main Authors: Chen, Sen, Li, Zheng, Gao, Yuan, Zhang, Haibao, Liu, Bowen, Ying, Minju, Liu, Zhongwei
• Format: Article
• Language: English
• Subjects: C:Ni film; Graphene; Rapid thermal annealing; Reactive direct current magnetron sputtering
• ISSN: 0042-207X; 1879-2715
• DOI: 10.1016/j.vacuum.2024.113421

In this study, few-layer graphene was directly fabricated on a SiO2/Si substrate through the rapid thermal annealing of Ni films with low carbon content (C:Ni) deposited by reactivedirect current magnetron sputtering (DCMS). XPS, XRD and TEM results confirmed that carbon atoms were doped into the Ni lattice and there are no carbon clusters embedded in the films. The study investigated various parameters and factors affecting graphene preparation, including the carbon content in the Ni film, the thickness of the Ni film, the annealing temperature, the heating rate, and other relevant factors. Raman spectroscopy revealed that few-layer graphene occurs on the surface of the C:Ni film, with I2D/IG ratio greater than 1 and ID/IG less than 0.2, indicating the excellent quality of the graphene. Raman mapping images confirmed that the monolayer graphene covered approximately 90 % of the 10 × 10 μm2 area on the surface. Furthermore, it was observed that the low carbon content of the Ni film facilitated the preparation of few-layer graphene. High temperatures were found to enhance carbon diffusion, which has a great impact on the layer number and quality of graphene. The synthesis of graphene can be attributed to metal-induced crystallization and carbon diffusion mechanisms. The experimental findings are expected to greatly advance the synthesis of graphene and broaden its potential applications in various fields. Monolayer graphene can be prepared directly on SiO2/Si substrates by annealing nickel films with low carbon content. The number of graphene layers is determined by the carbon content in the nickel film and the preparation parameters. [Display omitted]