1. Emergent ferroelectricity in subnanometer binary oxide films on silicon
- Author
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Cheema, Suraj S, Shanker, Nirmaan, Hsu, Shang-Lin, Rho, Yoonsoo, Hsu, Cheng-Hsiang, Stoica, Vladimir A, Zhang, Zhan, Freeland, John W, Shafer, Padraic, Grigoropoulos, Costas P, Ciston, Jim, and Salahuddin, Sayeef
- Subjects
Macromolecular and Materials Chemistry ,Chemical Sciences ,Engineering ,Physical Sciences ,Materials Engineering ,Affordable and Clean Energy ,General Science & Technology - Abstract
The critical size limit of voltage-switchable electric dipoles has extensive implications for energy-efficient electronics, underlying the importance of ferroelectric order stabilized at reduced dimensionality. We report on the thickness-dependent antiferroelectric-to-ferroelectric phase transition in zirconium dioxide (ZrO2) thin films on silicon. The emergent ferroelectricity and hysteretic polarization switching in ultrathin ZrO2, conventionally a paraelectric material, notably persists down to a film thickness of 5 angstroms, the fluorite-structure unit-cell size. This approach to exploit three-dimensional centrosymmetric materials deposited down to the two-dimensional thickness limit, particularly within this model fluorite-structure system that possesses unconventional ferroelectric size effects, offers substantial promise for electronics, demonstrated by proof-of-principle atomic-scale nonvolatile ferroelectric memory on silicon. Additionally, it is also indicative of hidden electronic phenomena that are achievable across a wide class of simple binary materials.
- Published
- 2022