Field sensitivity in spin-valve sandwiches with antiferromagnetic NiO films

Author

Lee, S.S. ; Hwang, D.G. ; Park, C.M. ; Lee, K.A. ; Kim, M.Y. ; Rhee, J.R.

Author_Institution

Dept. of Phys., Sangji Univ., Wonju, South Korea

Volume

32

Issue

5

fYear

1996

fDate

9/1/1996 12:00:00 AM

Firstpage

3416

Lastpage

3418

Abstract

We have investigated the MR ratios and the field sensitivities in Ni₈₁Fe₁₅/Cu/Ni₈₁Fe₁₉ spin-valve sandwiches grown on antiferromagnetic NiO films as a function of the NiO thickness and the uniaxial deposition field. The MR ratio has a maximum value of 4.5% at 420 Å of NiO and 180 Oe of uniaxial deposition field, and a field sensitivity of 0.6%/Oe. In order to obtain a higher MR ratio and field sensitivity, we have studied the effects of adding a Co layer between the interfaces of NiFe and Cu and also the effects of a NiO film on top or at bottom on the spin-valve sandwiches. The MR sandwiches with the Co layer increases to 8.2%, however, the sensitivity decreases to 0.37%/Oe due to the high coercivity of Co. The Co inserted structure with the NiO film on top has a low MR ratio of 5.7% and a high sensitivity of 5.8%/Oe. The thermal stability of the sandwiches with the NiO film on top is superior to that of the NiO film at bottom

Keywords

antiferromagnetic materials; copper; iron alloys; magnetic multilayers; magnetic thin films; magnetoresistance; nickel alloys; nickel compounds; Co layer; Ni₈₁Fe₁₅-Cu-Ni₈₁Fe₁₉; Ni₈₁Fe₁₅/Cu/Ni₈₁Fe₁₉ spin-valve sandwich; NiO; antiferromagnetic NiO film; coercivity; field sensitivity; magnetoresistance ratio; thermal stability; uniaxial deposition field; Antiferromagnetic materials; Coercive force; Glass; Magnetic field measurement; Magnetic films; Magnetoresistance; Physics; Sputtering; Thermal resistance; Thermal stability;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.538642

Filename

538642