Title :
Effect of Au underlayers on GMR properties of NiFe/Cu/CoFe sandwiches
Author :
Wang, D. ; Daughton, J.M. ; Smith, C.H. ; Chen, E.Y.
Author_Institution :
Nonvolatile Electron. Inc., Eden Prairie, MN, USA
fDate :
9/1/1996 12:00:00 AM
Abstract :
We have developed a new structure that has a GMR sandwich and one or two Au layers at the outer boundaries (Au/NiFe/Cu/CoFe/Au). This structure is designed to employ a specular reflection of conduction electrons from the Au layers. The potential advantages of this structure compared to multilayer films are low saturation field, high sheet resistance and the ability to use scissoring fields from a current for patterned narrow line structures, while maintaining a high GMR. All layers were deposited using rf diode sputtering. Coercivity difference between the two magnetic layers is used to realize the antiparallel alignments of the magnetizations of NiFe and CoFe layers. Comparing with similar structures without Au layers, the new structure has a GMR increase of 35% after discounting the shunting effect of the Au underlayers. Single layer Au films as thin as 40 Å have been made with a large specularity parameter when deposited on Bi2O3 and after annealing
Keywords :
annealing; cobalt alloys; copper; ferromagnetic materials; giant magnetoresistance; gold; iron alloys; magnetic multilayers; magnetisation; nickel alloys; sputter deposition; 40 A; Au underlayers; Au-NiFe-Cu-CoFe-Au; Au/NiFe/Cu/CoFe/Au structure; Bi2O3; GMR properties; GMR sandwich; NiFe/Cu/CoFe sandwiches; annealing; antiparallel alignments; coercivity; conduction electrons; high sheet resistance; large specularity parameter; low saturation field; magnetization; patterned narrow line structures; rf diode sputtering; scissoring fields; shunting effect; specular reflection; Coercive force; Diodes; Electrons; Gold; Magnetic films; Magnetic multilayers; Optical films; Reflection; Saturation magnetization; Sputtering;
Journal_Title :
Magnetics, IEEE Transactions on
