Vanadium-Doped Hafnium Oxide: A High-Endurance Ferroelectric Thin Film with Demonstrated Negative Capacitance

This study proposes and validates a novel CMOS-compatible ferroelectric thin-film insulator made of vanadium-doped hafnium oxide (V:HfO2) by using an optimized atomic layer deposition (ALD) process. Comparative electrical performance analysis of metal–ferroelectric–metal capacitors with varying V-doping concentrations, along with advanced material characterizations, confirmed the ferroelectric behavior and reliability of V:HfO2. With remnant polarization (Pr) values up to 20 μC/cm2, a coercive field (Ec) of 1.5 MV/cm, excellent endurance (>1011 cycles without failure, extrapolated to 1012 cycles), projected 10-year nonvolatile retention (>100 days measured), and large grain sizes of ∼180 nm, V:HfO2 emerges as a promising robust candidate for nonvolatile memory and neuromorphic applications. Importantly, negative capacitance (NC) effects were observed and analyzed in V:HfO2 through pulsed measurements, demonstrating its potential for NC applications. Finally, this novel ferroelectric shows potential as a gating insulator for future 3-terminal vanadium dioxide Mott-insulator devices and sensors, achieved through an all-ALD process.