The annealing effect on GMR properties of PtMn-based spin valve

Abstract

The second annealing effect on GMR properties has been investigated for postdeposition-annealed PtMn spin valve. A sudden change in MR ratio, exchange bias field and inter-layer coupling field occurred at about 325degreesC. This annealing temperature is close to the blocking temperature for the PtMn spin valve indicating 310degreesC. It is considered that the FCT structure of PtMn layer can promote Mn diffusion through the grain boundary, leading to a sudden decrease in magnetic properties. Therefore, PtMn layer as an anti ferromagnetic material may not be suitable for the advanced head material. (C) 2002 Elsevier Science B.V, All rights reserved.