As semiconductor devices continue shrinking toward the sub-3 nm (especially 1-nm) technology nodes, conventional silicon transistors are increasingly limited by severe short-channel effects and degraded gate electrostatic control. Two-dimensional (2D) semiconductors, with atomically thin channels and excellent electrostatic, are considered promising candidates for future ultra-scaled electronic devices. However, one of the biggest challenges in sub-3 nm 2D MOSFETs is the long-standing trade-off between high driving current and strong gate controllability.
To address this issue, researchers from Chongqing Sanxia University of Science and Technology proposed a constituent-layer-selective doping (LSD) strategy for type-II ZnO/GaN van der Waals heterostructure MOSFETs. Their work demonstrates that the strategy can simultaneously improve carrier injection capability and electrostatic gate control through a current confinement mechanism.
Using first-principles quantum transport simulations, the researchers systematically investigated sub-3 nm double-gate ZnO/GaN MOSFETs. The ZnO/GaN heterostructure naturally exhibits type-II band alignment, where the conduction-band minimum is mainly localized in the ZnO layer while the valence-band maximum resides in the GaN layer. This intrinsic spatial separation provides an ideal platform for implementing layer-selective carrier modulation. In the proposed LSD configuration, only the ZnO layer in the source and drain regions is n-type doped, while the GaN layer remains intrinsic. In contrast, conventional fully doped devices introduce dopants into both ZnO and GaN layers.
The simulations revealed that the LSD strategy effectively confines electron transport within the ZnO layer and suppresses parasitic carrier accumulation in the GaN layer. As a result, the device exhibits reduced channel capacitance, suppressed drain-induced barrier lowering (DIBL), and significantly enhanced electrostatic gate control. Remarkably, even at the ultimate gate length of 1 nm, the proposed LSD-ZnO/GaN MOSFET achieved high on-state currents of 1493 μA/μm for high-performance applications and 392 μA/μm for low-power applications, while maintaining a low subthreshold swing of 78 mV/dec. These results outperform many previously reported 2D MOSFETs operating at comparable technology nodes.
“Traditional ultra-scaled MOSFETs usually face a trade-off between strong carrier injection and effective gate control,” said Prof. Lei Hu, the sole corresponding author of the study. “Our layer-selective doping strategy provides a feasible pathway to overcome this limitation by utilizing current confinement within the transport layer.”
The researchers further showed that the LSD concept is transferable to other type-II van der Waals heterostructures, like common MoS 2 /WSe 2 and MoS 2 /MoSSe systems, suggesting broad applicability for future ultra-scaled transistor design.
“Our work not only demonstrates the potential of ZnO/GaN heterostructures for sub-3 nm electronics, but also provides a general design strategy for next-generation post-Moore nanoelectronic devices,” Hu added.
The team expects the proposed strategy to inspire further research into ultra-scaled 2D transistors.
DOI: 10.26599/NR.2026.94908827
The full research article is available at:
https://www.sciopen.com/article/10.26599/NR.2026.94908827
Research Group Introduction
The research group led by Prof. Lei Hu focuses on theoretical simulations of low-dimensional semiconductor and 2D MOSFETs. Prof. Lei Hu has published more than 30 SCI papers as first or corresponding author, with a total of 56 SCI-indexed publications and an h-index of 21. The group welcomes academic exchanges and long-term collaborations with researchers and institutions worldwide in the fields of two-dimensional materials and MOSFETs.
Google Scholar: https://scholar.google.com/citations?user=BgYlZ7cAAAAJ&hl=zh-CN
About Nano Research
Nano Research is a peer-reviewed, open access, international and interdisciplinary research journal, sponsored by Tsinghua University and the Chinese Chemical Society, published by Tsinghua University Press on the platform SciOpen. It publishes original high-quality research and significant review articles on all aspects of nanoscience and nanotechnology, ranging from basic aspects of the science of nanoscale materials to practical applications of such materials. After 18 years of development, it has become one of the most influential academic journals in the nano field. Nano Research has published more than 1,000 papers every year from 2022, with its cumulative count surpassing 8,000 articles. In 2025 InCites Journal Citation Reports, its 2025 IF is 9.4 (8.3, 5 years), and it continues to be the Q1 area among the four subject classifications. Nano Research Award, established by Nano Research together with TUP and Springer Nature in 2013, and Nano Research Young Innovators (NR45) Awards, established by Nano Research in 2018, have become international academic awards with global influence.
Nano Research
Theoretically Breaking the 1-nm limit: Layer-selective doping enables high-performance 2D transistors with enhanced gate control
31-Jul-2026