High quality epitaxial graphene on 4H-SiC by face-to-face growth in ultra-high vacuum

Zebardastan, Negar; Bradford, Jonathan; Lipton-Duffin, Josh; MacLeod, Jennifer; Ostrikov, Kostya (Ken); Tomellini, Massimo; Motta, Nunzio

Abstract

Epitaxial graphene on SiC is the most promising substrate for the next generation 2D electronics, due to the possibility to fabricate 2D heterostructures directly on it, opening the door to the use of all technological processes developed for silicon electronics. To obtain a suitable material for large scale applications, it is essential to achieve perfect control of size, quality, growth rate and thickness. Here we show that this control on epitaxial graphene can be achieved by exploiting the face-to-face annealing of SiC in ultra-high vacuum. With this method, Si atoms trapped in the narrow space between two SiC wafers at high temperatures contribute to the reduction of the Si sublimation rate, allowing to achieve smooth and virtually defect free single graphene layers. We analyse the products obtained on both on-axis and off-axis 4H-SiC substrates in a wide range of temperatures (1300 °C-1500 °C), determining the growth law with the help of x-ray photoelectron spectroscopy (XPS). Our epitaxial graphene on SiC has terrace widths up to 10 μm (on-axis) and 500 nm (off-axis) as demonstrated by atomic force microscopy and scanning tunnelling microscopy, while XPS and Raman spectroscopy confirm high purity and crystalline quality.

Citation

Zebardastan, N., Bradford, J., Lipton-Duffin, J., MacLeod, J., Ostrikov, K. (., Tomellini, M., & Motta, N. (2023). High quality epitaxial graphene on 4H-SiC by face-to-face growth in ultra-high vacuum. Nanotechnology, 34(10), Article 105601. https://doi.org/10.1088/1361-6528/aca8b2

• Journal Article Type: Article
• Acceptance Date: Dec 5, 2022
• Online Publication Date: Dec 23, 2022
• Publication Date: Mar 5, 2023
• Deposit Date: Jan 9, 2023
• Publicly Available Date: Dec 24, 2023
• Journal: Nanotechnology
• Print ISSN: 0957-4484
• Electronic ISSN: 1361-6528
• Publisher: IOP Publishing
• Peer Reviewed: Peer Reviewed
• Volume: 34
• Issue: 10
• Article Number: 105601
• DOI: https://doi.org/10.1088/1361-6528/aca8b2
• Keywords: epitaxial graphene, face to face growth, thermal decomposition, ultra-high vacuum, silicon sublimation, SiC
• Public URL: https://nottingham-repository.worktribe.com/output/15924349
• Publisher URL: https://iopscience.iop.org/article/10.1088/1361-6528/aca8b2
• Additional Information: This is the Accepted Manuscript version of an article accepted for publication in Nanotechnology. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The Version of Record is available online at https://iopscience.iop.org/article/10.1088/1361-6528/aca8b2