Abstract
Ferroelectricity in binary oxides including hafnia and zirconia has riveted the attention of the scientific community due to the highly unconventional physical mechanisms and the potential for the integration of these materials into semiconductor workflows. Over the last decade, it has been argued that behaviours such as wake-up phenomena and an extreme sensitivity to electrode and processing conditions suggest that ferroelectricity in these materials is strongly influenced by other factors, including electrochemical boundary conditions and strain. Here we argue that the properties of these materials emerge due to the interplay between the bulk competition between ferroelectric and structural instabilities, similar to that in classical antiferroelectrics, coupled with non-local screening mediated by the finite density of states at surfaces and internal interfaces. Via the decoupling of electrochemical and electrostatic controls, realized via environmental and ultra-high vacuum piezoresponse force microscopy, we show that these materials demonstrate a rich spectrum of ferroic behaviours including partial-pressure-induced and temperature-induced transitions between ferroelectric and antiferroelectric behaviours. These behaviours are consistent with an antiferroionic model and suggest strategies for hafnia-based device optimization.
Original language | English |
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Pages (from-to) | 1144-1151 |
Number of pages | 8 |
Journal | Nature Materials |
Volume | 22 |
Issue number | 9 |
DOIs | |
State | Published - Sep 2023 |
Funding
This effort (K.P.K., Y.L., S.S.F., S.T.J., T.M., J.F.I., S.C., E.C.D. and S.V.K.) was supported as part of the Center for 3D Ferroelectric Microelectronics (3DFeM), an Energy Frontier Research Center funded by the US Department of Energy, Office of Science, Basic Energy Sciences under award number DE-SC0021118. The scanning probe microscopy research was performed and partially supported at Oak Ridge National Laboratory’s Center for Nanophase Materials Sciences, a US Department of Energy, Office of Science User Facility. S.T.J. acknowledges support from the US National Science Foundation’s Graduate Research Fellowship Program via grant number DGE-1842490. A.N.M. received funding from the National Academy of Sciences of Ukraine (grant N 4.8/23-II, ‘Innovative materials and systems with magnetic and/or electrodipole ordering for the needs of using spintronics and nanoelectronics in strategically important issues of new technology’, fund 1230) and was also supported by the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement no. 778070. Some authors (S.C. and E.C.D.) acknowledge the use of the Materials Characterization Facility at Carnegie Mellon University, supported by MCF-677785.
Funders | Funder number |
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center for 3D Ferroelectric Microelectronics | |
Oak Ridge National Laboratory | |
National Science Foundation | DGE-1842490 |
U.S. Department of Energy | |
Office of Science | |
Basic Energy Sciences | DE-SC0021118 |
Horizon 2020 Framework Programme | |
H2020 Marie Skłodowska-Curie Actions | 778070 |
National Academy of Sciences of Ukraine | N 4.8/23-II |