Title :
Effect of seed layer on the magnetoresistance characteristics in a-CoNbZr-based spin valves
Author :
Cho, Hae Seok ; Ueda, Fumiomi ; Hou, Chunhong ; Fujiwara, Hideo
Author_Institution :
Center for Mater. for Inf. Technol., Alabama Univ., Tuscaloosa, AL, USA
fDate :
7/1/1998 12:00:00 AM
Abstract :
We have investigated an amorphous-based spin valve structure of NiO(40 nm)/Co(2)/Cu(t)/Co(1.2)/CoNbZr(20) for the application of magnetic random access memory. The spin valves were prepared on Si(100) by sputtering, and characterized by XRD, VSM, AFM/MFM, and 4-point probe. To improve GMR characteristics by controlling the interfacial structures of the Co/Cu/Co trilayer, we employed NiFe as a seed layer for NiO and achieved a GMR ratio of 10.7%. The spin valves with the seed layer exhibited lower ferromagnetic coupling between the pinned and free layers, lower pinning fields, and higher coercivities of the pinned layer than the spin valves without a seed layer. These phenomena were discussed mainly in terms of interfacial microstructural change as well as Neel´s orange peel model
Keywords :
X-ray diffraction; amorphous magnetic materials; atomic force microscopy; cobalt alloys; coercive force; giant magnetoresistance; interface structure; magnetic film stores; magnetic force microscopy; magnetic multilayers; magnetoresistive devices; niobium alloys; random-access storage; sputtered coatings; zirconium alloys; 4-point probe; AFM; MFM; Neel´s orange peel model; NiO-Co-Cu-Co-CoNbZr; Si; Si(100) substrate; VSM; XRD; coercivity; ferromagnetic coupling; giant magnetoresistance; interfacial structures; magnetic random access memory; pinning fields; seed layer; spin valves; sputtering; Amorphous magnetic materials; Degradation; Giant magnetoresistance; Magnetic materials; Probes; Random access memory; Soft magnetic materials; Spin valves; Sputtering; X-ray scattering;
Journal_Title :
Magnetics, IEEE Transactions on
