A study of surface roughness issues in magnetic tunnel junctions

This research focuses on the spin-dependent tunneling phenomenon in magnetic tunnel junction. Based on the free electron model, it is found that the tunneling magnetoresistance and the exchange coupling are greatly modified by introducing the interface roughness into the basic Ferromagnet/Insulator/Ferromagnet structure. Experimentally, the surface roughness of the Ni80Fe20 bottom electrode is controlled by applying an rf substrate bias during the deposition. Magnetic tunnel junction elements are fabricated by using shadow mask technique. Experimental results show that the barrier properties and the performance of the magnetic tunnel junction elements depend on the microstructure of tunnel barrier.

Author dc:creator

• HU JIANGFENG

• magnetic tunnel junction; magnetic thin films; multilayer structure; surface roughness; tunneling magnetoresistance; interlayer exchange coupling