Piezoelectricity in hafnia

Sangita Dutta; Pratyush Buragohain; Sebastjan Glinsek; Claudia Richter; Hugo Aramberri; Haidong Lu; Uwe Schroeder; Emmanuel Defay; Alexei Gruverman; Jorge Íñiguez

doi:10.1038/s41467-021-27480-5

Piezoelectricity in hafnia

Nat Commun. 2021 Dec 15;12(1):7301. doi: 10.1038/s41467-021-27480-5.

Authors

Sangita Dutta^{1

2}, Pratyush Buragohain³, Sebastjan Glinsek⁴, Claudia Richter⁵, Hugo Aramberri⁴, Haidong Lu³, Uwe Schroeder⁵, Emmanuel Defay⁴, Alexei Gruverman⁶, Jorge Íñiguez^{7

8}

Affiliations

¹ Materials Research and Technology Department, Luxembourg Institute of Science and Technology, 5 avenue des Hauts-Fourneaux, L-4362, Esch/Alzette, Luxembourg. sangita.dutta@list.lu.
² Department of Physics and Materials Science, University of Luxembourg, 41 Rue du Brill, Belvaux, L-4422, Luxembourg. sangita.dutta@list.lu.
³ Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE, 68588-0299, USA.
⁴ Materials Research and Technology Department, Luxembourg Institute of Science and Technology, 5 avenue des Hauts-Fourneaux, L-4362, Esch/Alzette, Luxembourg.
⁵ NaMLab gGmbH, Noethnitzer Strasse 64 a, 01187, Dresden, Germany.
⁶ Department of Physics and Astronomy, University of Nebraska-Lincoln, Lincoln, NE, 68588-0299, USA. agruverman2@unl.edu.
⁷ Materials Research and Technology Department, Luxembourg Institute of Science and Technology, 5 avenue des Hauts-Fourneaux, L-4362, Esch/Alzette, Luxembourg. jorge.iniguez@list.lu.
⁸ Department of Physics and Materials Science, University of Luxembourg, 41 Rue du Brill, Belvaux, L-4422, Luxembourg. jorge.iniguez@list.lu.

Abstract

Because of its compatibility with semiconductor-based technologies, hafnia (HfO₂) is today's most promising ferroelectric material for applications in electronics. Yet, knowledge on the ferroic and electromechanical response properties of this all-important compound is still lacking. Interestingly, HfO₂ has recently been predicted to display a negative longitudinal piezoelectric effect, which sets it apart from classic ferroelectrics (e.g., perovskite oxides like PbTiO₃) and is reminiscent of the behavior of some organic compounds. The present work corroborates this behavior, by first-principles calculations and an experimental investigation of HfO₂ thin films using piezoresponse force microscopy. Further, the simulations show how the chemical coordination of the active oxygen atoms is responsible for the negative longitudinal piezoelectric effect. Building on these insights, it is predicted that, by controlling the environment of such active oxygens (e.g., by means of an epitaxial strain), it is possible to change the sign of the piezoelectric response of the material.