From Growth Surface to Device Interface: Preserving Metallic Fe under Monolayer Hexagonal Boron Nitride

Sabina Caneva, Marie Blandine Martin, Lorenzo D'Arsié, Adrianus I. Aria, Hikmet Sezen, Matteo Amati, Luca Gregoratti, Hisashi Sugime, Santiago Esconjauregui, John Robertson, Stephan Hofmann, Robert S. Weatherup

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

We investigate the interfacial chemistry between Fe catalyst foils and monolayer hexagonal boron nitride (h-BN) following chemical vapor deposition and during subsequent atmospheric exposure, using scanning electron microscopy, X-ray photoemission spectroscopy, and scanning photoelectron microscopy. We show that regions of the Fe surface covered by h-BN remain in a metallic state during exposure to moist air for ∼40 h at room temperature. This protection is attributed to the strong interfacial interaction between h-BN and Fe, which prevents the rapid intercalation of oxidizing species. Local Fe oxidation is observed on bare Fe regions and close to defects in the h-BN film (e.g., domain boundaries, wrinkles, and edges), which over the longer-term provide pathways for slow bulk oxidation of Fe. We further confirm that the interface between h-BN and metallic Fe can be recovered by vacuum annealing at ∼600 °C, although this is accompanied by the creation of defects within the h-BN film. We discuss the importance of these findings in the context of integrated manufacturing and transfer-free device integration of h-BN, particularly for technologically important applications where h-BN has potential as a tunnel barrier such as magnetic tunnel junctions.

Original languageEnglish
Pages (from-to)29973-29981
Number of pages9
JournalACS Applied Materials and Interfaces
Volume9
Issue number35
DOIs
Publication statusPublished - 2017 Sep 6
Externally publishedYes

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Keywords

  • chemical vapor deposition (CVD)
  • hexagonal boron nitride (h-BN)
  • interfacial chemistry
  • iron (Fe)
  • X-ray photoelectron spectroscopy (XPS)

ASJC Scopus subject areas

  • Materials Science(all)

Cite this

Caneva, S., Martin, M. B., D'Arsié, L., Aria, A. I., Sezen, H., Amati, M., Gregoratti, L., Sugime, H., Esconjauregui, S., Robertson, J., Hofmann, S., & Weatherup, R. S. (2017). From Growth Surface to Device Interface: Preserving Metallic Fe under Monolayer Hexagonal Boron Nitride. ACS Applied Materials and Interfaces, 9(35), 29973-29981. https://doi.org/10.1021/acsami.7b08717