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Impact of La Concentration on Ferroelectricity of La-Doped HfO₂ Epitaxial Thin Films.

ABSTRACT: Epitaxial thin films of HfO₂ doped with La have been grown on SrTiO₃(001) and Si(001), and the impact of the La concentration on the stabilization of the ferroelectric phase has been determined. Films with 2-5 at. % La doping present the least amount of paraelectric monoclinic and cubic phases and exhibit the highest polarization, having a remanent polarization above 20 μC/cm². The dopant concentration results in an important effect on the coercive field, which is reduced with increasing La content. Combined high polarization, high retention, and high endurance of at least 10¹⁰ cycles is obtained in 5 at. % La-doped films.

SUBMITTER: Song T

PROVIDER: S-EPMC8613842 | biostudies-literature | 2021 Nov

REPOSITORIES: biostudies-literature

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Impact of La Concentration on Ferroelectricity of La-Doped HfO2 Epitaxial Thin Films.

Song Tingfeng T Tan Huan H Bachelet Romain R Saint-Girons Guillaume G Fina Ignasi I Sánchez Florencio F

ACS applied electronic materials 20211019 11

Epitaxial thin films of HfO2 doped with La have been grown on SrTiO3(001) and Si(001), and the impact of the La concentration on the stabilization of the ferroelectric phase has been determined. Films with 2-5 at. % La doping present the least amount of paraelectric monoclinic and cubic phases and exhibit the highest polarization, having a remanent polarization above 20 μC/cm2. The dopant concentration results in an important effect on the coercive field, which i ...[more]

PMID: 34841249

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