Operando observation of reversible oxygen migration and phase transitions in ferroelectric devices

التفاصيل البيبلوغرافية
العنوان: Operando observation of reversible oxygen migration and phase transitions in ferroelectric devices
المؤلفون: Nukala, Pavan, Ahmadi, Majid, Wei, Yingfen, de Graaf, Sytze, Matzen, Sylvia, Zandbergen, Henny W., Kooi, Bart, Noheda, Beatriz
سنة النشر: 2020
المجموعة: Condensed Matter
مصطلحات موضوعية: Condensed Matter - Materials Science
الوصف: Unconventional ferroelectricity, robust at reduced nanoscale sizes, exhibited by hafnia-based thin-films presents tremendous opportunities in nanoelectronics. However, the exact nature of polarization switching remains controversial. Here, we investigate epitaxial Hf0.5Zr0.5O2 (HZO) capacitors, interfaced with oxygen conducting metals (La0.67Sr0.33MnO3, LSMO) as electrodes, using atomic resolution electron microscopy while in situ electrical biasing. By direct oxygen imaging, we observe reversible oxygen vacancy migration from the bottom to the top electrode through HZO and reveal associated reversible structural phase transitions in the epitaxial LSMO and HZO layers. We follow the phase transition pathways at the atomic scale and identify that these mechanisms are at play both in tunnel junctions and ferroelectric capacitors switched with sub-millisecond pulses. Our results unmistakably demonstrate that oxygen voltammetry and polarization switching are intertwined in these materials.
Comment: 29 pages (including supplementary), 4 main figures, 6 supplementary figures
نوع الوثيقة: Working Paper
DOI: 10.1017/S1431927621003640
URL الوصول: http://arxiv.org/abs/2010.10849
رقم الأكسشن: edsarx.2010.10849
قاعدة البيانات: arXiv
الوصف
DOI:10.1017/S1431927621003640