Anisotropic etching of 2D layered materials

Abstract

Two-dimensional (2D) layered materials with unique physicochemical properties, such as graphene, transition metal dichalcogenides, and hexagonal boron nitride, have shown considerable potential in the electrical and electronics industries as well as society. To realize the practical applications of 2D materials, the size, shape, and edge structures must be refined. Etching is a critical processing step in the semiconducting industry and its potential as an efficient approach for fabricating diverse nanostructures of 2D materials has been demonstrated, broadening their applications in the field of nanoelectronics. In this paper, we present an overview of recent advances in anisotropic etching of various 2D materials. Anisotropic etching and the associated mechanisms are discussed in context of the synthesis, processing, and characterization of 2D materials. An overview of the applications of anisotropic etched 2D materials is provided. Finally, the challenges and future opportunities for anisotropic etching of 2D materials are discussed.

Keywords

2D materials / Anisotropic etching / Nanostructures / Graphene / MoS₂

Declaration of Competing Interest

Yue Hong is an editor for ChemPhysMater and was not involved in the editorial review or the decision to publish this article. All authors declare that there are no competing interests.

CRediT authorship contribution statement

Yuge Zhang: Writing - original draft, Investigation, Formal analysis. Qian Liu: Writing - original draft, Investigation, Formal analysis. Deliang Zhang: Writing - review & editing, Formal analysis. Yue Hong: Writing - review & editing, Formal analysis. Qiang Li: Writing - review & editing, Supervision, Funding acquisition, Conceptualization.

Acknowledgements

This work was financially supported by the Natural Science Foundation of Shandong Province (No. ZR2023MB028), the Grant for Taishan Scholar Advantage Characteristic Discipline of Shandong Province, the Start-up Grant for QiLu Young Scholars of Shandong University.

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