Kinetically stabilized ferroelectricity in bulk single-crystalline HfO2:Y
Document Type
Article
Publication Date
6-1-2021
Abstract
HfO2, a simple binary oxide, exhibits ultra-scalable ferroelectricity integrable into silicon technology. This material has a polymorphic nature, with the polar orthorhombic (Pbc21) form in ultrathin films regarded as the plausible cause of ferroelectricity but thought not to be attainable in bulk crystals. Here, using a state-of-the-art laser-diode-heated floating zone technique, we report the Pbc21 phase and ferroelectricity in bulk single-crystalline HfO2:Y as well as the presence of the antipolar Pbca phase at different Y concentrations. Neutron diffraction and atomic imaging demonstrate (anti)polar crystallographic signatures and abundant 90°/180° ferroelectric domains in addition to switchable polarization with negligible wake-up effects. Density-functional-theory calculations indicate that the yttrium doping and rapid cooling are the key factors for stabilization of the desired phase in bulk. Our observations provide insights into the polymorphic nature and phase control of HfO2, remove the upper size limit for ferroelectricity and suggest directions towards next-generation ferroelectric devices.
Identifier
85099844540 (Scopus)
Publication Title
Nature Materials
External Full Text Location
https://doi.org/10.1038/s41563-020-00897-x
e-ISSN
14764660
ISSN
14761122
PubMed ID
33495629
First Page
826
Last Page
832
Issue
6
Volume
20
Grant
N00014-17-1-2770
Fund Ref
Office of Naval Research
Recommended Citation
Xu, Xianghan; Huang, Fei Ting; Qi, Yubo; Singh, Sobhit; Rabe, Karin M.; Obeysekera, Dimuthu; Yang, Junjie; Chu, Ming Wen; and Cheong, Sang Wook, "Kinetically stabilized ferroelectricity in bulk single-crystalline HfO2:Y" (2021). Faculty Publications. 4081.
https://digitalcommons.njit.edu/fac_pubs/4081