スピンバルブライクトンネル接合における下地電極層の磁気抵抗への影響  [in Japanese] Effects of Under-Electrode Layers on Mgnetoresistance in Spin-Valve-Like Tunnel Junctions  [in Japanese]

The relation between the under-electrode layers of spin-valve-like tunneling junctions and the tunneling magnetoresistive effect was investigated. Al, Cu, and Pt, which all have low resistivity, were selected for the electrode layer. The roughness of the oxidized Al surface with an Al electrode layder of more than 10nm thickness increased drastically. In all junctions with Al layers thicker than 30nm, the tunneling magnetoresistive effect was not observed. On the other hand, junctions with a Cu electrode exhibited an MR ratio of over 10%, ever for Cu thickness of up to 80 nm. The MR ratio decreased with increasing roughness of the oxidized Al surface, irrespective of the electrode materials.