Browse Prior Art Database

MULTILAYERED FREE LAYER TO IMPROVE SOFT MAGNETIC PROPERTIES

IP.com Disclosure Number: IPCOM000014064D
Original Publication Date: 2000-Apr-01
Included in the Prior Art Database: 2003-Jun-19
Document File: 1 page(s) / 39K

Publishing Venue

IBM

Abstract

A new freelayer structure is described which provides improved easy axis coercivity, anisotropy field, and hard axis coercivity for spin valve applications. The new structure has a NiFe interlayer between the oxide seedlayer and the CoFe/NiFe/CoFe/Cu structure. The full spin valve structure is NiMnO seed/NiFe/CoFe/NiFe/CoFe/Cu/CoFe/NiMn/Ta. Experiments have shown that the CoFe/NiFe/CoFe freelayer structure provides improved thermal stability on oxide seeded spin valve structures. However, the addition of the CoFe layer increases the Hc, Hch, and Hk of the spin valve structures. The present method of inserting a thin NiFe layer at the oxide interface lowers the Hc, Hch and Hk of the freelayer structure. The addition of the NiFe interlayer does not degrade the dR/R and other properties of the spin valve structure. The Hc,Hch, and Hk of the freelayer structure as a function of the NiFe interlayer thickness is shown in a figure below. PROPERTIES OF NiMnO/ NiFe /CoFe/NiFe/CoFe/Cu STRUCTURE 25

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 1

MULTILAYERED FREE LAYER TO IMPROVE SOFT MAGNETIC PROPERTIES

A new freelayer structure is described which provides improved easy axis
coercivity, anisotropy field, and hard axis coercivity for spin valve
applications. The new structure has a NiFe interlayer between the oxide
seedlayer and the CoFe/NiFe/CoFe/Cu structure. The full spin valve structure
is NiMnO seed/NiFe/CoFe/NiFe/CoFe/Cu/CoFe/NiMn/Ta.

Experiments have shown that the CoFe/NiFe/CoFe freelayer structure provides
improved thermal stability on oxide seeded spin valve structures. However,
the addition of the CoFe layer increases the Hc, Hch, and Hk of the spin valve
structures. The present method of inserting a thin NiFe layer at the oxide
interface lowers the Hc, Hch and Hk of the freelayer structure. The addition
of the NiFe interlayer does not degrade the dR/R and other properties of the
spin valve structure. The Hc,Hch, and Hk of the freelayer structure as a
function of the NiFe interlayer thickness is shown in a figure below.

PROPERTIES OF NiMnO/ NiFe /CoFe/NiFe/CoFe/Cu STRUCTURE

25

20

15

10

5

0

Total Free Layer =~60A As deposited state

Hc (Oe.) Hc h (Oe.) Hk (Oe.)

0 2 4 6 810

NiFe Thickness (A)

1

[This page contains 3 pictures or other non-text objects]