[19a-E216-1~12] 10.1 Emerging materials in spintronics and magnetics (including fabrication and charactrization methodologies)

▲ [19a-E216-1] Electron tunneling through perpendicularly magnetized cobalt ferrite films grown on metallic TiN layers

〇Masaaki Tanaka¹, Katsuyoshi Naruse¹, Kosuke Nomura¹, Kodai Kutsukake¹, Takaya Okuno², Syuta Honda³, Teruo Ono², Ko Mibu¹ (1.Nagoya Inst. Tech., 2.Kyoto Univ., 3.Kansai Univ.)

Keywords:Spin filtering, Magnetic insulator

Magnetic insulator CoFe2O4 (CFO) films grown along the [001] direction with in-plane tensile strain have large perpendicular magnetic anisotropy (PMA) In this study, we investigated PMA and electron tunneling characteristics of CFO films on nonmagnetic metal layers. CFO films with different Co compositions were grown on MgO (001) substrates with metallic TiN buffer layers using pulsed laser deposition technique. Magnetization measurement indicated that PMA of CFO was realized with decreasing Co compositions. We have succeeded in fabricating perpendicularly magnetized CFO films on nonmagnetic metal TiN films. The tunneling property was investigated for Au/Cr/CFO/TiN and CoFe/MgO/CFO/TiN tunnel junctions with the junction diameter of 10 μm. The voltage-current curves of the tunnel junctions show typical tunneling characters. The perpendicularly magnetized CFO films applicable for the spin-filtering devices were thus realized on nonmagnetic metals.