Granted Patent B1

US 8,760,818 · App. 13/737,374 · Granted Jun 24, 2014

Abstract

Claims (56)

1. A magnetic storage element comprising:

a substrate comprising NiFe, wherein the substrate comprises a first crystalline structure;

a seed layer on the substrate, wherein the seed layer is configured to substantially obstruct a transfer of the first crystalline structure to the buffer layer and the upper layer;

wherein the seed layer is configured to provide a second crystalline structure different from the first crystalline structure;

a buffer layer on the seed layer, wherein the buffer layer is configured to substantially maintain the second crystalline structure;

wherein a structure of the buffer layer substantially matches a crystalline structure of the upper layer; and

an upper layer on the buffer layer, the upper layer comprising a Heusler alloy grown epitaxially.

2. The magnetic storage element of claim 1 , wherein the first crystalline structure comprises a face-centered cubic structure, and the second crystalline structure comprises a structure that is about body-centered cubic.

3. The magnetic storage element of claim 1 ,

wherein the seed layer comprises a first magnetic sub-layer with an amorphous structure and a second magnetic sub-layer with the second crystalline structure that is about body-centered cubic; and

wherein the second crystalline structure is developed through a process for changing the amorphous structure of the first magnetic sub-layer, the process selected from the group consisting of an annealing process, a phase change process, a re-crystallization process, and combinations thereof.

4. The magnetic storage element of claim 1 :

wherein the substrate comprises a first crystalline structure; and

wherein the seed layer and the buffer layer are configured to provide a foundation structure for the Heusler alloy of the upper layer that is different from the first crystalline structure.

5. The magnetic storage element of claim 1 :

wherein the Heusler alloy comprises a L21/B2 ordering; and

wherein the Heusler alloy comprises preferably, but not limited, a CFMS alloy.

6. The magnetic storage element of claim 1 :

wherein the seed layer comprises substantially magnetic characteristics; and

wherein the buffer layer comprises substantially non-magnetic characteristics.

7. The magnetic storage element of claim 1 :

wherein the upper layer comprises a free layer comprising the Heusler alloy; and

wherein the magnetic storage element further comprises:

a spacer on the free layer;

a reference layer on the spacer, the reference layer comprising a Heusler alloy; and

a capping layer on the reference layer.

8. The magnetic storage element of claim 7 :

wherein the Heusler alloy of the free layer comprises a L21/B2 ordering;

wherein the Heusler alloy of the reference layer comprises a L21/B2 ordering;

wherein the magnetic storage element further comprises:

an anti-ferromagnetic layer on the reference layer;

a non-magnetic coupling layer on the reference layer;

an anti-ferromagnetically coupled pinned layer on the non-magnetic coupling layer, wherein the reference layer is anti-ferromagnetically coupled via the non-magnetic coupling layer; and

an anti-ferromagnetic pinning layer on the anti-ferromagnetically coupled pinned layer;

wherein the capping layer is on the anti-ferromagnetic pinning layer; and

wherein the Heusler alloy of the reference layer is grown epitaxially.

9. The magnetic storage element of claim 1 :

wherein the upper layer comprises a reference layer, the reference layer comprising the Heusler alloy; and

wherein the magnetic storage element further comprises:

a spacer on the reference layer;

a free layer on the spacer, the free layer comprising a Heusler alloy; and

a capping layer on the free layer.

10. The magnetic storage element of claim 9 :

wherein the Heusler alloy of the reference layer comprises a L21/B2 ordering;

wherein the Heusler alloy of the free layer comprises a L21/B2 ordering; and

wherein the Heusler alloy of the free layer is grown epitaxially.

11. The magnetic storage element of claim 1 :

wherein the seed layer comprises a multi-layer structure with one or more materials selected from the group consisting of NiFe, Ta, Ti, amorphous CoFeB, CoFe, a material comprising a magnetic CFMS Heusler alloy, and combinations thereof; and

wherein the buffer layer comprises one or more materials selected from the group consisting of Ta, Ti, Cr, Ru, Cu, Ag, Al, W, a Ta alloy, a Cr alloy, a Ru alloy, a Cu alloy, a Ag alloy, a W alloy, a NiAl alloy, and combinations thereof.

12. The magnetic storage element of claim 1 :

wherein the seed layer comprises a multi-layer structure with one or more materials selected from the group consisting of NiFe, Ta, Ti, amorphous CoFeB, CoFe, a material comprising a magnetic CFMS Heusler alloy, and combinations thereof; and

wherein the buffer layer comprises one or more materials selected from the group consisting of Cu2CrAl, Cu2AlSi, a material comprising a non-magnetic Heusler alloy, and combinations thereof.

13. The magnetic storage element of claim 1 :

wherein the magnetic storage element is a current perpendicular to plane giant magneto-resistance (GMR) reader;

wherein a shield layer is selected from the group consisting of the substrate, the seed layer, and combinations thereof; and

wherein the shield layer acts as a shield for the GMR reader.

Assignments (9)