Magnetic tunnel junctions based on partially-oxidized-iron electrodes

摘要

Partially-oxidized-iron(Fe-O)-based magnetic tunnel junctions with large magnetoresistance have been fabricated. The compositions, and the structural and transport properties of the two Fe-O electrodes are characterized. The top Fe-O layer containing 25%-28% oxygen shows a metallic characteristic with fine grain structure. No crystalline iron oxides axe detected in the layer. The bottom Fe-O layer whose surface was oxidized during the oxidation process of the Al layer reveals the formation of alpha-Fe2O3 at the surface. The alpha-Fe2O3(104) is likely to be epitaxially grown on the Fe(110) plane. The layer shows a nonmetallic transport feature with negative temperature coefficient of resistance. [References: 20]