Effects of Annealing on the Microstructure and Giant Magnetoresistance of Co-Cu-Based Spin Valves

Published

March 1, 2001

Author(s)

M A. Mangan, G Spanos, Robert McMichael, P J. Chen, William F. Egelhoff Jr.

Abstract

The effect of annealing on the microstructure and giant magnetoresistive properties of NiO/Co/Cu/Co bottom spin valves is investigated using the conventional and high-resolution transmission electron microscopy. The value of giant Magnetoresistance (GMR) of these spin valves is observed to decrease from 12.2 % to 2.7 % after annealing for 30 min at 335 degrees C. This decrease is attributed to an inrease in the roughness of the Co and Cu layers. In annealed specimens, grain boundary grooving is also observed in the antiferromagnetic NiO Pinning layer at the NiO/Co interface, and the location of these grooves correlate with waviness in the Co/Cu interfaces. An increase in the Neel orange-peel coupling between the ferromagnetic Co layers, resulting from the increased roughness of the Co/Cu interfaces, accompanies the degradation of the GMR.

Citation

Metallurgical and Materials Transactions A-Physical Metallurgy and Materials Science

Volume

32

Issue

No. 3

Pub Type

Journals

Keywords

annealing, giant magnetoresistance (GMR), interface, microstructure, spin valves

Citation

Mangan, M. , Spanos, G. , McMichael, R. , Chen, P. and Egelhoff Jr., W. (2001), Effects of Annealing on the Microstructure and Giant Magnetoresistance of Co-Cu-Based Spin Valves, Metallurgical and Materials Transactions A-Physical Metallurgy and Materials Science (Accessed October 20, 2025)