Ferroelectricity in atomic-scale titanium dioxide dielectric films
Summary
Ferroelectricity at atomic-scale thickness would have important applications in next-generation electronics. Here, we report that a ferroelectric phase can be stabilized in titanium dioxide (TiO2) films, a commonly known dielectric that is widely used in semiconductor technologies, by reducing thickness to <3 nanometers. Importantly, this ferroelectricity persists down to 1-nanometer thickness, approximately twice the unit-cell dimension. This thickness-dependent dielectric-to-ferroelectri
Content
# Ferroelectricity in atomic-scale titanium dioxide dielectric films
*Published: 2026 Apr 16*
Ferroelectricity at atomic-scale thickness would have important applications in
next-generation electronics. Here, we report that a ferroelectric phase can be
stabilized in titanium dioxide (TiO2) films, a commonly known dielectric that is
widely used in semiconductor technologies, by reducing thickness to <3
nanometers. Importantly, this ferroelectricity persists down to 1-nanometer
thickness, approximately twice the unit-cell dimension. This thickness-dependent
dielectric-to-ferroelectric phase transition demonstrates that an otherwise
centrosymmetric, nonferroic fluorite-structure oxide can undergo structural
inversion-symmetry breaking and exhibit voltage-switchable polarization. Atomic
layer deposition-based low-temperature (<400°C) synthesis and the stability of
this ferroelectricity on both silicon (Si) and amorphous surfaces [such as
amorphous silicon dioxide (SiO2) and amorphous carbon films] demonstrate the
feasibility of integration with a large variety of materials.
DOI: 10.1126/science.aec9417