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Complementary carbon nanotube metal–oxide–semiconductor field-effect transistors with localized solid-state extension doping


Low-dimensional semiconductors such as one-dimensional carbon nanotubes could be used to shrink the gate length of metal–oxide–semiconductor field-effect transistors (MOSFETs) below the limits of silicon-based transistors. However, the development of industry-compatible doping strategies and polarity-control methods for such systems is challenging. Here we report top-gate complementary carbon nanotube MOSFETs in which localized conformal solid-state extension doping is used to set the device polarity and achieve performance matching. The channel of the transistors remains undoped, providing complementary metal–oxide–semiconductor-compatible n- and p-MOSFET threshold voltages of +0.29 V and −0.25 V, respectively. The foundry-compatible fabrication process implements localized charge transfer in the extensions from either defect levels in silicon nitride (SiNx) for n-type devices or an electrostatic dipole at the SiNx/aluminium oxide (Al2O3) interface for p-type devices. We observe SiNx donor defect densities approaching 5 × 1019 cm−3, which could sustain carbon nanotube carrier densities of 0.4 nm−1 in the extensions of scaled nanotube devices. Our technique is potentially applicable to other advanced field-effect transistor channel materials, including two-dimensional semiconductors.

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Fig. 1: CNT device architecture comparison.
Fig. 2: Top-gate complementary CNT MOSFETs with the devices’ polarity set by localized conformal solid-state extension doping.
Fig. 3: Device layout, capacitance-voltage characteristics, channel-carrier mobility and density.
Fig. 4: Development of solid-state extension doping.
Fig. 5: Modelling of solid-state extension doping.

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Data availability

The data that support the findings of this study are available from the corresponding author upon reasonable request.


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We acknowledge the use of facilities and instrumentation supported by the National Science Foundation through the University of California San Diego Materials Research Science and Engineering Center DMR-2011924.

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Authors and Affiliations



Z.Z. and M.P. contributed equally. Z.Z. conducted the device fabrication and measurement. M.P. developed the impedance and doping models, device layout and data analysis. G.P., W.E.S., N.S. and T-E.L. contributed to device fabrication, and S.N. supported impedance measurements. S.-K.S. and G.D. contributed to device modelling. T.-A.C. provided the CNT substrates. S.L.L., V.D.-H.H. and C.-F.H. provided TEM analysis. I.R., A.C.K., P.B. and H.-S.P.W. guided the project. Z.Z. and M.P. prepared the paper draft, and all the authors commented on the final version.

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Correspondence to Matthias Passlack.

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Zhang, Z., Passlack, M., Pitner, G. et al. Complementary carbon nanotube metal–oxide–semiconductor field-effect transistors with localized solid-state extension doping. Nat Electron 6, 999–1008 (2023).

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