Polymer-Free Transfer Platform for the Fabrication of Graphene Liquid Cells.

Session

Poster Session Three

Authors

Mr Sam Sullivan-allsop (1), Dr Wendong Wang (1), Dr Nick Clark (1), Dr Rongsheng Cai (1), Dr Alex Summerfield (1), Mr Qizhen Li (1), Dr Mingwei Zhou (1), Prof Andrey Kretinin (1), Prof Roman Gorbachev (1), Prof Sarah Haigh (1)

Affiliations

1. University of Manchester

Keywords

Polymer-Free

Graphene Liquid Cells

Scanning Transmission Electron Microscopy

Abstract text

Graphene liquid cells are traditionally fabricated with polymer transfer layers but these unavoidably introduce hydrocarbon contamination which is challenging to remove. Here we present our method for the fabrication of ultra clean engineered graphene liquid cells (GLCs) with controlled liquid volumes, through the application of our novel polymer-free 2D heterostructure assembly process using flexible SiNx cantilevers. The design of the cantilevers includes an array of lithographically etched 3 µm holes in the SiNx membrane. The GLC structure involves encapsulating hBN – which has lithographically etched cavities containing the liquid samples – between the two few-layer graphene (FLG) windows. The GLC is fabricated by picking up 2D crystals sequentially to cover a hole in the cantilever. The end of the cantilever can then be detached by fracture along a perforated edge and mounted upon a silicon chip for loading in the TEM. Through our cantilever based GLC fabrication process we have shown the clean and facile fabrication of heterostructure stack-based GLCs, using a ‘peel on and peel off’ technique with our cantilevers. High angle annular dark field scanning transmission electron microscopy (HAADF STEM) imaging of the sample reveals atomic resolution imaging of specimens in the liquid cell.