Magnetic tunnel junctions based on ferroelectric Hf0.5Zr0.5O2 tunnel barriers

Yingfen Wei; Sylvia Matzen; Guillaume Agnus; Mart Salverda; Pavan Nukala; Thomas Maroutian; Qihong Chen; Jianting Ye; Philippe Lecoeur; Beatriz Noheda

doi:10.1103/physrevapplied.12.031001

arXiv · 1902.08021

Magnetic tunnel junctions based on ferroelectric Hf0.5Zr0.5O2 tunnel barriers

Yingfen Wei·Sylvia Matzen·Guillaume Agnus·Mart Salverda·Pavan Nukala·Thomas Maroutian·Qihong Chen·Jianting Ye·Philippe Lecoeur·Beatriz Noheda

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Abstract

A ferroelectric tunnel barrier in between two ferromagnetic electrodes (multiferroic tunnel junction, MFTJ), is one of the most promising concepts for future microelectronic devices. In parallel, Hafnia based ferroelectrics are showing great potential for device miniaturization down to the nanoscale. Here we utilize ferroelectric Hf0.5Zr0.5O2 (HZO) with thickness of only 2 nm, epitaxially grown on La0.7Sr0.3MnO3 (LSMO) ferromagnetic electrodes, as a large band-gap insulating barrier integrated in MFTJs with cobalt top electrodes. As previously reported for other MFTJs with similar electrodes, the tunneling magnetoresistance (TMR) can be tuned and its sign can even be reversed by the bias voltage across the junction. We demonstrate four non-volatile resistance states generated by magnetic and electric field switching with high reproducibility in this system.

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Yingfen Wei, Sylvia Matzen, Guillaume Agnus, Mart Salverda, Pavan Nukala, Thomas Maroutian, Qihong Chen, Jianting Ye, Philippe Lecoeur, Beatriz Noheda. 2019-02-08. Magnetic tunnel junctions based on ferroelectric Hf0.5Zr0.5O2 tunnel barriers. https://doi.org/10.1103/physrevapplied.12.031001

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