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Layered Graphene Growth Directly on Sapphire Substrates for Applications.

ABSTRACT: Layer-by-layer graphene growth is demonstrated by repeating CVD growth cycles directly on sapphire substrates. Improved field-effect mobility values are observed for the bottom-gate transistors fabricated by using the bilayer graphene channel, which indicates an improved crystallinity is obtained after the second CVD growth cycle. Despite the poor wettability of copper on graphene surfaces, graphene may act as a thin and effective diffusion barrier for copper atoms. The low resistivity values of thin copper films deposited on thin monolayer MoS₂/monolayer graphene heterostructures have demonstrated its potential to replace current thick liner/barrier stacks in back-end interconnects. The unique van der Waals epitaxy growth mode will be helpful for both homo- and heteroepitaxy on 2D material surfaces.

SUBMITTER: Chang CJ

PROVIDER: S-EPMC9026027 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Layered Graphene Growth Directly on Sapphire Substrates for Applications.

Chang Che-Jia CJ Tsai Po-Cheng PC Su Wei-Ya WY Huang Chun-Yuan CY Lee Po-Tsung PT Lin Shih-Yen SY

ACS omega 20220404 15

Layer-by-layer graphene growth is demonstrated by repeating CVD growth cycles directly on sapphire substrates. Improved field-effect mobility values are observed for the bottom-gate transistors fabricated by using the bilayer graphene channel, which indicates an improved crystallinity is obtained after the second CVD growth cycle. Despite the poor wettability of copper on graphene surfaces, graphene may act as a thin and effective diffusion barrier for copper atoms. The low resistivity values of ...[more]

PMID: 35474834

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