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Heterojunction tunnel triodes based on two-dimensional metal selenide and three-dimensional silicon


Low power consumption in the static and dynamic modes of operation is a key requirement in the development of modern electronics. Tunnel field-effect transistors with direct band-to-band charge tunnelling and steep-subthreshold-slope transfer characteristics offer one potential solution. However, silicon and III–V heterojunction-based tunnel field-effect transistors suffer from low on-current densities and on/off current ratios at sub-60 mV decade–1 operation. Tunnel field-effect transistors based on two-dimensional materials can offer improved electrostatic control and potentially higher on-current densities and on/off ratios. Here we report gate-tunable heterojunction tunnel triodes that are based on van der Waals heterostructures formed from two-dimensional metal selenide and three-dimensional silicon. These triodes exhibit subthreshold slopes as low as 6.4 mV decade–1 and average subthreshold slopes of 34.0 mV decade–1 over four decades of drain current. The devices have a current on/off ratio of approximately 106 and an on-state current density of 0.3 µA µm–1 at a drain bias of –1 V.

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Fig. 1: Structure and characterization of 2D/3D heterojunction tunnel triode.
Fig. 2: Room-temperature electrical characteristics of InSe/Si 2D/3D HJ-TTs.
Fig. 3: Room-temperature electrical characteristics of InSe/Si 2D/3D HJ-TTs, control 2D InSe MOSFETs and TCAD-simulated devices.
Fig. 4: Temperature-dependent electrical characteristics of InSe/Si 2D/3D HJ-TTs.
Fig. 5: Performance comparison of InSe/Si 2D/3D HJ-TTs with reported sub-thermionic homo- and heterojunction TFETs and NC-FETs.

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Data availability

The data that support the conclusions of this study are available from the corresponding authors upon reasonable request. Source data are provided with this paper.

Code availability

Any codes used in this study are available from the corresponding authors upon request.


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D.J. and J.M. acknowledge primary support for this work by the Air Force Office of Scientific Research (AFOSR) FA9550-21-1-0035. D.J. also acknowledges partial support from the Intel Rising Star Award and the University Research Foundation (URF) at Penn. D.J. also acknowledges partial support from the University of Pennsylvania Materials Research Science and Engineering Center (MRSEC) (DMR-1720530) in addition to the usage of MRSEC-supported facilities. The sample fabrication, assembly and characterization were carried out at the Singh Center for Nanotechnology at the University of Pennsylvania, which is supported by the National Science Foundation (NSF) National Nanotechnology Coordinated Infrastructure Program grant NNCI-1542153. A.V.D. and S.K. acknowledge the support of Material Genome Initiative funding allocated to NIST. H.Z. acknowledges support from the US Department of Commerce, National Institute of Standards and Technology, under the financial assistance awards 70NANB19H138. T.B. and N.G. acknowledge support from the AFOSR under award no. FA9550-19RYCOR050.

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Authors and Affiliations



D.J. and J.M. conceived the idea/concept. D.J. directed the collaboration and execution. J.M. fabricated all the devices with assistance from B.S. and measured them with the assistance of X.L. Simulations were done by C.L., J.W., Y.G. and W.H. Electron microscopy and cross-sectional cutting of the devices was performed by H.Z. InSe crystals were grown by S.K. A.V.D. supervised the crystal synthesis, Hall measurements and electron microscopy. N.G. and T.B. performed the photoemission spectroscopy measurements. J.M., C.L. and D.J. co-wrote the manuscript with contributions from all the authors. Certain commercial equipment, instruments or materials are identified in this paper to specify the experimental procedure adequately. Such identification is not intended to imply recommendation or endorsement by the National Institute of Standards and Technology, nor is it intended to imply that the materials or equipment identified are necessarily the best available for the purpose.

Corresponding authors

Correspondence to Jinshui Miao or Deep Jariwala.

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D.J. and J.M. have filed an invention disclosure based on this work. The other authors declare no competing interests.

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Nature Electronics thanks Vincent Tung and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Disclaimer: Certain commercial equipment, instruments, or materials are identified in this paper to specify the experimental procedure adequately. Such identification is not intended to imply recommendation or endorsement by the National Institute of Standards and Technology, nor is it intended to imply that the materials or equipment identified are necessarily the best available for the purpose.

Supplementary information

Supplementary Information

Supplementary Figs. 1–15, Sections 1–4 and Tables 1 and 2.

Source data

Source Data Fig. 2

Room-temperature electrical characteristics and band diagrams of InSe/p++Si 2D/3D HJ-TTs.

Source Data Fig. 3

Room-temperature electrical characteristics of InSe/Si 2D/3D HJ-TTs, control 2D InSe MOSFETs and TCAD-simulated devices.

Source Data Fig. 4

Temperature-dependent electrical characteristics of InSe/Si 2D/3D HJ-TTs.

Source Data Fig. 5

Performance comparison of the InSe/Si 2D/3D HJ-TTs with reported sub-thermionic homo- and heterojunction TFETs and NC-FETs.

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Miao, J., Leblanc, C., Wang, J. et al. Heterojunction tunnel triodes based on two-dimensional metal selenide and three-dimensional silicon. Nat Electron 5, 744–751 (2022).

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