Toward Nonvolatile Spin-Orbit Devices: Deposition of Ferroelectric Hafnia on Monolayer Graphene/Co/HM Stacks

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Suzanne Lancaster - , NaMLab - Nanoelectronic materials laboratory gGmbH (Author)
  • Iciar Arnay - , Madrid Institute for Advanced Studies in Nanoscience (Author)
  • Ruben Guerrero - , Madrid Institute for Advanced Studies in Nanoscience (Author)
  • Adrian Gudín - , Madrid Institute for Advanced Studies in Nanoscience (Author)
  • Alejandra Guedeja-Marrón - , Complutense University (Author)
  • Jose Manuel Diez - , Universidad Autónoma de Madrid (Author)
  • Jan Gärtner - , NaMLab - Nanoelectronic materials laboratory gGmbH (Author)
  • Alberto Anadón - , Madrid Institute for Advanced Studies in Nanoscience (Author)
  • Maria Varela - , Complutense University (Author)
  • Julio Camarero - , Universidad Autónoma de Madrid (Author)
  • Thomas Mikolajick - , Chair of Nanoelectronics, NaMLab - Nanoelectronic materials laboratory gGmbH (Author)
  • Paolo Perna - , Madrid Institute for Advanced Studies in Nanoscience (Author)
  • Stefan Slesazeck - , NaMLab - Nanoelectronic materials laboratory gGmbH (Author)

Abstract

While technologically challenging, the integration of ferroelectric thin films with graphene spintronics potentially allows the realization of highly efficient, electrically tunable, nonvolatile memories through control of the interfacial spin-orbit driven interaction occurring at graphene/Co interfaces deposited on heavy metal supports. Here, the integration of ferroelectric Hf0.5Zr0.5O2 on graphene/Co/heavy metal epitaxial stacks is investigated via the implementation of several nucleation methods in atomic layer deposition. By employing in situ Al2O3 as a nucleation layer sandwiched between Hf0.5Zr0.5O2 and graphene, the Hf0.5Zr0.5O2 demonstrates a remanent polarization (2Pr) of 19.2 μC/cm2. Using an ex situ, naturally oxidized sputtered Ta layer for nucleation, we could control 2Pr via the interlayer thickness, reaching maximum values of 28 μC/cm2 with low coercive fields. Magnetic hysteresis measurements taken before and after atomic layer deposition show strong perpendicular magnetic anisotropy, with minimal deviations in the magnetization reversal pathways due to the Hf0.5Zr0.5O2 deposition process, thus pointing to a good preservation of the magnetic stack including single-layer graphene. X-ray diffraction measurements further confirm that the high-quality interfaces demonstrated in the stack remain unperturbed by the ferroelectric deposition and anneal. The proposed graphene-based ferroelectric/magnetic structures offer the strong advantages of ferroelectricity and ferromagnetism at room temperature, enabling the development of novel magneto-electric and nonvolatile in-memory spin-orbit logic architectures with low power switching.

Details

Original languageEnglish
Pages (from-to)16963-16974
Number of pages12
JournalACS Applied Materials and Interfaces
Volume15
Issue number13
Publication statusPublished - 5 Apr 2023
Peer-reviewedYes

External IDs

PubMed 36951382
WOS 000959587400001
ORCID /0000-0003-3814-0378/work/142256355

Keywords

DFG Classification of Subject Areas according to Review Boards

Subject groups, research areas, subject areas according to Destatis

Keywords

  • atomic layer deposition, ferroelectric hafnia, nonvolatile devices, perpendicular magnetic anisotropy, spin−orbit devices, Ferroelectric hafnia, Spin-orbit devices, Nonvolatile devices, Atomic layer deposition, Perpendicular magnetic anisotropy