Stabilizing Schottky-to-Ohmic Switching in HfO2-Based Ferroelectric Films via Electrode DesignShow others and affiliations
2025 (English)In: Advanced Science, E-ISSN 2198-3844, Vol. 12, no 8, article id 2409566Article in journal (Refereed) Published
Abstract [en]
The discovery of ferroelectric phases in HfO2-based films has reignited interest in ferroelectrics and their application in resistive switching (RS) devices. This study investigates the pivotal role of electrodes in facilitating the Schottky-to-Ohmic transition (SOT) observed in devices consisting of ultrathin epitaxial ferroelectric Hf0.93Y0.07O2 (YHO) films deposited on La0.67Sr0.33MnO3-buffered Nb-doped SrTiO3 (NbSTO|LSMO) with Ti|Au top electrodes. These findings indicate combined filamentary RS and ferroelectric switching occurs in devices with designed electrodes, having an ON/OFF ratio of over 100 during about 105 cycles. Transport measurements of modified device stacks show no change in SOT when the ferroelectric YHO layer is replaced with an equivalent hafnia-based layer, Hf0.5Zr0.5O2 (HZO). However, incomplete SOT is observed for variations in the top electrode thickness or material, as well as LSMO electrode thickness. This underscores the importance of employing oxygen-reactive electrodes and a bottom electrode with reduced conductivity to stabilize SOT. These findings provide valuable insights for enhancing the performance of ferroelectric RS devices through integration with filamentary RS mechanism.
Place, publisher, year, edition, pages
Wiley , 2025. Vol. 12, no 8, article id 2409566
Keywords [en]
electrochemistry, ferroelectricity, hafnia, interfaces, resistive switching
National Category
Condensed Matter Physics Atom and Molecular Physics and Optics
Identifiers
URN: urn:nbn:se:kth:diva-385272DOI: 10.1002/advs.202409566ISI: 001392887100001PubMedID: 39789844Scopus ID: 2-s2.0-85214390639OAI: oai:DiVA.org:kth-385272DiVA, id: diva2:2086126
Note
QC 20260713
2026-07-132026-07-132026-07-13Bibliographically approved