CN-122029976-A - Magneto-resistance effect element and magnetic memory

Abstract

A magneto-resistance effect element comprises a substrate, a foundation layer provided on the substrate, and a laminated portion provided on the foundation layer, wherein the laminated portion comprises a magnetization free layer, a reference layer, and a nonmagnetic layer provided between the magnetization free layer and the reference layer. The base layer includes 2 or more metal nitride layers, and a metal oxynitride layer provided between a first metal nitride layer and a second metal nitride layer among the 2 or more metal nitride layers.

Inventors

• TANG ZHENYAO
• SASAKI TOMOO

Assignees

• TDK株式会社

Dates

Publication Date

20260512

Application Date

20230929

Claims (10)

1. 1. A magneto-resistance effect element is provided with: A substrate; A base layer disposed on the substrate A lamination portion provided on the underlayer, the lamination portion including a magnetization free layer, a reference layer, and a nonmagnetic layer provided between the magnetization free layer and the reference layer, The base layer is provided with 2 or more metal nitride layers, and a metal oxynitride layer provided between a first metal nitride layer and a second metal nitride layer among the 2 or more metal nitride layers.
2. 2. The magnetoresistance effect element according to claim 1, wherein a metal constituting the first metal nitride layer is different from a metal constituting the second metal nitride layer.
3. 3. The magnetoresistance effect element according to claim 2, wherein the magnetoresistance effect element further comprises a metal layer provided between the foundation layer and the lamination portion.
4. 4. The magnetoresistance effect element according to claim 3, wherein the reference layer comprises a first ferromagnetic layer, a second ferromagnetic layer, and a nonmagnetic interposed layer disposed between the first ferromagnetic layer and the second ferromagnetic layer so as to exchange-couple the first ferromagnetic layer and the second ferromagnetic layer.
5. 5. The magnetoresistance effect element according to claim 4, wherein the first metal nitride layer is provided on the substrate side of the metal oxynitride layer, the second metal nitride layer is provided on the laminated portion side of the metal oxynitride layer, and the first metal nitride layer is thickest in the underlayer.
6. 6. The magnetoresistance effect element according to claim 4, wherein the underlayer further comprises a third metal nitride layer as the 2 or more metal nitride layers, wherein among the first metal nitride layer, the second metal nitride layer, and the third metal nitride layer, a metal nitride layer located in a middle in a thickness direction of the underlayer is thickest.
7. 7. The magnetoresistance effect element according to claim 5, wherein a thickness of a metal nitride layer disposed closest to a substrate side among the 2 or more metal nitride layers is greater than a thickness of the metal oxynitride layer.
8. 8. The magnetoresistance effect element according to claim 5, wherein a metal constituting a metal nitride layer closest to the lamination portion side of the 2 or more metal nitride layers is the same as a metal constituting a metal nitride layer closest to the substrate of the 2 or more metal nitride layers.
9. 9. The magnetoresistance effect element according to claim 6, wherein the thickness of the underlayer is 50nm or more.
10. 10. A magnetic memory comprising a plurality of the magnetoresistance effect elements according to any of claims 1 to 9.

Description

Magneto-resistance effect element and magnetic memory Technical Field The present invention relates to a magnetoresistance effect element and a magnetic memory. Background A giant magnetoresistance effect (GMR) element, a tunnel magnetoresistance effect (TMR) element, and other magnetoresistance effect elements having a laminate of a magnetization free layer made of a ferromagnetic material, a nonmagnetic spacer layer, and a reference layer (fixed layer) made of a ferromagnetic material, which are laminated in this order, are being developed as elements for use in devices such as magnetic field sensors, magnetic heads, and Magnetoresistive Random Access Memories (MRAM). Prior art literature Non-patent literature Non-patent document 1: S. Yuasa et al Nature Materials 3, 868-871, 2004 Non-patent literature 2:J Slonczewski J. Magn. Mater 159 (1996) L1 Non-patent literature 3:S, TAKAHASHI AND S, maekawa, phys, rev, lett, 80, 1758 (1998) Disclosure of Invention First, the technical problem to be solved For devices such as MRAM using the magnetoresistance element described above, it is desirable to improve the flatness and crystallinity of the layers constituting the magnetoresistance element from the viewpoint of reliability concerning the lifetime of the device and the like. The present invention has been made in view of the above-described problems, and an object thereof is to provide a magnetoresistance effect element having high flatness and crystallinity of a layer constituting the element, and a magnetic memory using the magnetoresistance effect element. (II) technical scheme In order to solve the above-described problems, a magnetoresistance effect element according to the present invention includes a substrate, an underlayer provided on the substrate, and a laminated portion provided on the underlayer, the laminated portion including a magnetization free layer, a reference layer, and a nonmagnetic layer provided between the magnetization free layer and the reference layer, the underlayer including 2 or more metal nitride layers, and a metal oxynitride layer provided between a first metal nitride layer and a second metal nitride layer among the 2 or more metal nitride layers. In the magnetoresistance effect element according to the present invention, since at least 3 layers exist in the underlayer, there are at least 2 interfaces between 2 layers made of different materials. Therefore, since the layer formed on the interface is easily crystallized when the underlayer is formed, the crystallinity and flatness of the uppermost layer among the 2 or more metal nitride layers of the underlayer are improved as compared with the case where the entire underlayer 1 is formed only from the material constituting the uppermost layer. Therefore, crystallinity and flatness of the layer constituting the laminated portion formed on such a base layer can be improved. Further, in the magnetoresistance effect element according to the present invention, the metal constituting the first metal nitride layer may be different from the metal constituting the second metal nitride layer. In this case, since the at least 2 interfaces are formed by combining layers different from each other, the effect of improving the crystallinity and flatness of the layers constituting the laminated portion due to the presence of the at least 2 interfaces can be more effectively exerted. Further, the magnetoresistance effect element according to the present invention may further comprise a metal layer provided between the underlayer and the laminated portion. In this case, the crystallinity and flatness of the layer constituting the laminated portion formed on the metal layer can be further improved by the metal layer. Further, in the magnetoresistance effect element according to the present invention, the reference layer may include a first ferromagnetic layer, a second ferromagnetic layer, and a nonmagnetic interposed layer provided between the first ferromagnetic layer and the second ferromagnetic layer so as to exchange-couple the first ferromagnetic layer and the second ferromagnetic layer. In this case, the magnetization direction of the reference layer can be stabilized more. Further, in the magnetoresistance effect element according to the present invention, the first metal nitride layer may be provided on the substrate side of the metal oxynitride layer, the second metal nitride layer may be provided on the stacked portion side of the metal oxynitride layer, and the first metal nitride layer may be thickest in the underlayer. In this case, at least 1 of the above-mentioned at least 2 interfaces of the base layer are located close to the lamination portion. Therefore, the above-described effect of improving the crystallinity and flatness of the layers constituting the laminated portion due to the presence of at least 2 interfaces can be more effectively exerted. Further, in the magnetoresistance effect element according to the present inve