Tunneling Field-Effect Transistors in Two-Dimensional Materials

Tunneling field-effect transistors (TFETs) exploit quantum mechanical band-to-band tunnelling to overcome the thermionic limit on subthreshold swing, promising orders-of-magnitude reductions in power dissipation compared with conventional MOSFETs. Two-dimensional (2D) materials such as transition metal dichalcogenides, phosphorene and other layered semiconductors are ideal TFET channels owing to their atomically thin bodies, absence of dangling bonds at surfaces and highly tunable band-alignment in van der Waals heterostructures. By carefully engineering channel composition, contact materials and interlayer interfaces, researchers have demonstrated steep subthreshold slopes well below 60 mV decade⁻¹, high ON-currents at low supply voltages and suppressed off-state leakage. Integration of TFETs in neuromorphic hardware, digital logic and hybrid hybrid CMOS/TFET platforms has further underlined their practical potential. Ongoing work focuses on optimising material quality, interface engineering and novel device architectures to realise scalable, energy-efficient electronics for applications in low-power computing, sensing and the Internet of Things.

Research from Nature Portfolio

Recent studies have showcased two-dimensional TFETs in energy-efficient neuromorphic hardware. Novel digital circuits built from transition metal dichalcogenide (TMD)-based tunnel FETs achieved leaky-integrate-fire and Hebbian learning functions at supply voltages below 0.5 V, delivering two orders of magnitude improvement in energy per operation relative to leading silicon FinFET platforms. Another advance employed an atomic threshold-switching element intimately integrated with a MoS₂ channel to induce internal voltage amplification, achieving subthreshold swings as low as 4.5 mV decade⁻¹ over five decades of current while maintaining ultralow leakage. Foundational work on vertical WS₂/SnS₂ van der Waals heterostructures demonstrated pristine 2D–2D interfaces and favourable broken-gap alignment, yielding high ON-state currents, negative differential resistance and sub-60 mV decade⁻¹ slopes at room temperature. These efforts underline the importance of tight interface control and hybrid device integration in realising sub-thermionic switching.

Tunneling Field-Effect Transistors in Two-Dimensional Materials publication trend

The graph below shows the total number of articles in tunneling field-effect transistors in two-dimensional materials across all publications each year (not limited to Nature Index journals).

Technical terms

Tunneling Field-Effect Transistor (TFET): A transistor in which current flows by quantum mechanical band-to-band tunnelling, enabling subthreshold swings below the thermionic limit of 60 mV decade⁻¹.

Two-Dimensional Materials: Atomically thin crystals with strong in-plane bonding and weak out-of-plane van der Waals interactions, offering pristine surfaces and tunable electronic properties.

Subthreshold Swing (SS): The gate-voltage change required to increase the drain current by one decade in the subthreshold region; lower SS indicates steeper switching and lower power consumption.

Van der Waals Heterostructure: A stack of different 2D materials held together by van der Waals forces, allowing clean interfaces and customisable band alignments without lattice matching constraints.

Band-to-Band Tunnelling (BTBT): Quantum tunnelling of carriers directly from the valence band of the source to the conduction band of the channel, the fundamental switching mechanism in TFETs.

References

1. An ultra energy-efficient hardware platform for neuromorphic computing enabled by 2D-TMD tunnel-FETs. Nature Communications (2024).
2. Atomic threshold-switching enabled MoS2 transistors towards ultralow-power electronics. Nature Communications (2020).
3. Vertical WS2/SnS2 van der Waals Heterostructure for Tunneling Transistors. Scientific Reports (2018).
4. High-throughput approach to explore cold metals for electronic and thermoelectric devices. npj Computational Materials (2024).
5. WSe2/SnSe2 vdW heterojunction Tunnel FET with subthermionic characteristic and MOSFET co-integrated on same WSe2 flake. npj 2D Materials and Applications (2020).
6. 2D materials-based nanoscale tunneling field effect transistors: current developments and future prospects. npj 2D Materials and Applications (2022).