Creation of room temperature half-metallic magnetic tunnel junction having a spinel crystal structure

2014 Fiscal Year Final Research Report

• Project/Area Number: 25790039
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Applied materials
• Research Institution: Tohoku University
• Principal Investigator: NIIZEKI Tomohiko 東北大学, 原子分子材料科学高等研究機構, 助教 (40567749)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: スピネル / マグネタイト / 強磁性トンネル接合 / ハーフメタル

Outline of Final Research Achievements

Towards the creation of room temperature half-metal ferromagnetic tunnel junction using Magnetite (Fe3O4) which is the spinel-type oxide material and is expected to be half-metallic from the theoretical calculation as the electrodes and a transition metal oxide having the same spinel structure as a barrier, we established the elemental technologies. First, we have succeeded in producing a very flat substrate by heat treatment of the MgO substrate. Then performed a selection of the barrier layer. Although CoCr2O4 which was originally planned was found to be ineligible , MgTi2O4 was found to be excellent as a barrier material in terms of surface morphology as well as crystallinity. Furthermore, Fe3O4 as electrodes and CoFe2O4 as the magnetic pinning layer have been successfully selectively grown with high accuracy just by the control of the oxygen flow rate, respectively.

Free Research Field

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