title: Sub-nanometer atomic layer deposition for spintronics in magnetic tunnel junctions based on graphene spin-filtering membranes.
abstract: We report on the successful integration of low-cost, conformal, and versatile atomic layer deposited (ALD) dielectric in Ni–Al2O3–Co magnetic tunnel junctions (MTJs) where the Ni is coated with a spin-filtering graphene membrane. The ALD tunnel barriers, as thin as 0.6 nm, are grown layer-by-layer in a simple, low-vacuum, ozone-based process, which yields high-quality electron-transport barriers as revealed by tunneling characterization. Even under these relaxed conditions, including air exposure of the interfaces, a significant tunnel magnetoresistance is measured highlighting the robustness of the process. The spin-filtering effect of graphene is enhanced, leading to an almost fully inversed spin polarization for the Ni electrode of −42%. This unlocks the potential of ALD for spintronics with conformal, layer-by-layer control of tunnel barriers in magnetic tunnel junctions toward low-cost fabrication and down-scaling of tunnel resistances.
authors.forename: Marie-Blandine
authors.initials: MB
authors.lastname: Martin
authors.forename: Bruno
authors.initials: B
authors.lastname: Dlubak
authors.forename: Robert S
authors.initials: RS
authors.lastname: Weatherup
authors.forename: Heejun
authors.initials: H
authors.lastname: Yang
authors.forename: Cyrile
authors.initials: C
authors.lastname: Deranlot
authors.forename: Karim
authors.initials: K
authors.lastname: Bouzehouane
authors.forename: Frédéric
authors.initials: F
authors.lastname: Petroff
authors.forename: Abdelmadjid
authors.initials: A
authors.lastname: Anane
authors.forename: Stephan
authors.initials: S
authors.lastname: Hofmann
authors.forename: John
authors.initials: J
authors.lastname: Robertson
authors.forename: Albert
authors.initials: A
authors.lastname: Fert
authors.forename: Pierre
authors.initials: P
authors.lastname: Seneor