Wafer-scale high-κ HfO2 dielectric films with sub-5-Å equivalent oxide thickness for 2D MoS2 transistors
Year: 2026
Type: article
Abstract: High-κ gate dielectrics are indispensable in modern transistor technology and play a pivotal role in efficient capacitive gating and suppression of leakage currents. However, the realization of industry-compatible high-κ gate dielectrics at a sub-5-Å equivalent oxide thickness (EOT) remains challenging. Here we report the realization of 1.3-nm thick hafnium oxide (HfO2) dielectrics via an industry-compatible multiple oxidation atomic layer deposition process at 200 °C. A low EOT down to 2.5 Å is demonstrated for 1.3-nm thick HfO2 dielectrics on metal gates with a low leakage current of 10−6 A/cm2 and a robust breakdown electric field of ~22.3 MV/cm. Remarkably, such low EOT high-κ/metal gates can be directly implanted into emerging two-dimensional (2D) transistors and low-power logic circuits on 8-inch wafer scale to showcase their potentials. The as-fabricated molybdenum disulfide (MoS2) transistors exhibit a large on-state current density of 260 µA/µm at source-drain bias of 0.5 V, a high on/off ratio of 108, an average subthreshold slope (SS) of 75 mV/dec, and small capacitance equivalent thickness (CET) values of 0.34 nm for gate-first transistors and 0.50 nm for gate-last transistors. Our ultra-scaled dielectrics hold significant promise for advanced semiconductor fabrication processes towards the angstrom era. The integration of high-κ dielectrics with low equivalent oxide thickness (EOT) is crucial for the development of 2D transistors. Here, the authors report the low-temperature fabrication of wafer-scale HfO2 dielectric films with sub-5-Å EOT and their application for the realization of high-performance 2D MoS2 transistors and circuits.
Source: Nature Communications
Institutions: Hong Kong Polytechnic University, Songshan Lake Materials Laboratory, City University of Hong Kong, Chinese Academy of Sciences, Institute of Physics, University of Chinese Academy of Sciences, University of Cambridge, University of Electronic Science and Technology of China, Max Planck Institute for the Structure and Dynamics of Matter
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $6,990
OpenAlex ID: W7125017805
