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. 2021 Jul 28;14(12):4894–4900. doi: 10.1007/s12274-021-3670-y

Field-effect at electrical contacts to two-dimensional materials

Yao Guo 1,✉, Yan Sun 1, Alvin Tang 2, Ching-Hua Wang 2, Yanqing Zhao 1, Mengmeng Bai 1, Shuting Xu 1, Zheqi Xu 1, Tao Tang 3, Sheng Wang 4, Chenguang Qiu 4, Kang Xu 5, Xubiao Peng 1, Junfeng Han 1, Eric Pop 2, Yang Chai 5,✉
PMCID: PMC8316888  PMID: 34336143

Abstract

The inferior electrical contact to two-dimensional (2D) materials is a critical challenge for their application in post-silicon very large-scale integrated circuits. Electrical contacts were generally related to their resistive effect, quantified as contact resistance. With a systematic investigation, this work demonstrates a capacitive metal-insulator-semiconductor (MIS) field-effect at the electrical contacts to 2D materials: The field-effect depletes or accumulates charge carriers, redistributes the voltage potential, and gives rise to abnormal current saturation and nonlinearity. On one hand, the current saturation hinders the devices’ driving ability, which can be eliminated with carefully engineered contact configurations. On the other hand, by introducing the nonlinearity to monolithic analog artificial neural network circuits, the circuits’ perception ability can be significantly enhanced, as evidenced using a coronavirus disease 2019 (COVID-19) critical illness prediction model. This work provides a comprehension of the field-effect at the electrical contacts to 2D materials, which is fundamental to the design, simulation, and fabrication of electronics based on 2D materials. graphic file with name 12274_2021_3670_Fig1_HTML.jpg

Electronic Supplementary Material

Supplementary material (results of the simulation and SEM) is available in the online version of this article at 10.1007/s12274-021-3670-y.

Keywords: field-effect, electrical contact, two-dimensional materials, nonlinearity, in-memory-computing

Electronic Supplementary Material

12274_2021_3670_MOESM1_ESM.pdf (4.4MB, pdf)

Field-effect at electrical contacts to two-dimensional materials

Acknowledgements

We thank Prof. H.-S. Philip Wong from Stanford University and Analysis & Testing Center, Beijing Institute of Technology for the support of this work. We thank Prof. Zhiyong Zhang and Prof. Qing Chen from Peking University for useful discussion. Yao Guo thanks Dr. I-Ting Wang for the valuable suggestions. This work was supported the National Natural Science Foundation of China (No.11804024).

Contributor Information

Yao Guo, Email: yaoguo@bit.edu.cn.

Yang Chai, Email: ychai@polyu.edu.hk.

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Supplementary Materials

12274_2021_3670_MOESM1_ESM.pdf (4.4MB, pdf)

Field-effect at electrical contacts to two-dimensional materials

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