Method of integration of a magnetoresistive structure

Patent metadata

Field	Value
Publication number	US-11631806-B2
Application number	US-202117317061-A
Country	US
Kind code	B2
Filing date	May 11, 2021
Priority date	Dec 17, 2010
Publication date	Apr 18, 2023
Grant date	Apr 18, 2023

Abstract

A method of manufacturing one or more interconnects to magnetoresistive structure comprising (i) depositing a first conductive material in a via; (2) etching the first conductive material wherein, after etching the first conductive material a portion of the first conductive material remains in the via, (3) partially filling the via by depositing a second conductive material in the via and directly on the first conductive material in the via; (4) depositing a first electrode material in the via and directly on the second conductive material in the via; (5) polishing a first surface of the first electrode material wherein, after polishing, the first electrode material is (i) on the second conductive material in the via and (ii) over the portion of the first conductive material remaining in the via; and (6) forming a magnetoresistive structure over the first electrode material.

First claim

What is claimed is:

1. A method of manufacturing an interconnect to a magnetoresistive structure, the method comprising:
forming a via within a first dielectric layer, the via including sidewalls;
depositing a first electrically conductive material in the via to form a layer of the first electrically conductive material on at least a portion of the sidewalls of the via;
after forming the layer of the first electrically conductive material, depositing a second electrically conductive material to at least partially fill the via and form a layer of the second electrically conductive material above a first surface of the first dielectric layer, and in contact with the first electrically conductive material;
removing a first portion of the layer of the second electrically conductive material, wherein, after the first portion is removed, a second portion of the second electrically conductive material remains above the first surface of the dielectric layer; and
forming a magnetoresistive structure above the second portion of the second electrically conductive material.

2. The method of claim 1 , wherein the first and second electrically conductive materials form a first electrical contact to the magnetoresistive structure, and the method further includes forming a second electrical contact, wherein forming a second electrical contact includes:
depositing a second dielectric material to form a second dielectric layer over the magnetoresistive structure;
depositing a third dielectric material to form a third dielectric layer over the second dielectric layer; and
performing one of more etching steps to form a trench through the second and third dielectric layers above the magnetoresistive structure and expose a portion of the magnetoresistive structure.

3. The method of claim 2 , further comprising depositing an electrically conductive metal in the trench to form a second electrical contact to the magnetoresistive structure.

4. The method of claim 3 , wherein the electrically conductive metal has the same composition as the first electrically conductive material, the second electrically conductive material, or both.

5. The method of claim 1 , wherein the first electrically conductive material is the same as the second electrically conductive material.

6. The method of claim 1 , wherein the first electrically conductive material and the second electrically conductive material are different materials.

7. The method of claim 1 , wherein the first electrically conductive material, the second electrically conductive material, or both, comprise tantalum, tantalum nitride, tungsten, ruthenium, aluminum, one or more aluminum alloys, copper, one or more copper alloys, titanium, titanium nitride, or titanium tungsten.

8. The method of claim 1 , wherein the sidewalls of the via are perpendicular to the first surface of the dielectric layer.

9. The method of claim 1 , wherein the first portion of the second electrically conductive material forms a depression corresponding to the location of the via; and
wherein removing the first portion of the second electrically conductive material removes the depression.

10. The method of claim 1 , wherein the step of removing the first portion of the second electrically conductive material incudes polishing the first portion using chemical mechanical polishing.

11. A method of manufacturing an interconnect to a magnetoresistive structure, the method comprising:
forming a via within a first dielectric layer, the via including sidewalls;
depositing a first electrically conductive material in the via to form a first layer of the first electrically conductive material in the via;
after forming the first layer of the first electrically conductive material, depositing a second electrically conductive material to form a layer of the second electrically conductive material in the via, wherein the layer of second electrically conductive material is in contact with the sidewalls of the via and the layer of first electrically conductive material;
removing a first portion of the layer of the second electrically conductive material, wherein, after the first portion is removed, a second portion of the second electrically conductive material remains above a first surface of the dielectric layer;
forming a magnetoresistive structure above the second portion of the second electrically conductive material;
depositing a second dielectric material to form a second dielectric layer over the magnetoresistive structure;
performing one or more etch steps to form a trench through the second dielectric layer and expose a portion of the magnetoresistive structure; and
forming a second contact to the magnetoresistive structure.

12. The method of claim 11 , wherein the first and second electrically conductive materials form a first electrical contact to the magnetoresistive structure, and the method further comprises depositing an electrically conductive metal in the trench to form a second electrical contact to the magnetoresistive structure.

13. The method of claim 1 , further comprising depositing a third dielectric material to form a third dielectric layer over the second dielectric layer.

14. The method of claim 13 , wherein the second dielectric material is more resistant to chemical mechanical polishing than the third dielectric material, and the method further comprises removing a portion of the third dielectric material using chemical mechanical polishing.

15. The method of claim 13 , wherein forming a trench includes forming a trench through the third dielectric material.

16. The method of claim 11 , wherein the first electrically conductive material is the same as the second electrically conductive material.

17. The method of claim 11 , wherein the first electrically conductive material and the second electrically conductive material are different materials.

18. A method of manufacturing an interconnect to a magnetoresistive structure, the method comprising:
forming a via within a first dielectric layer, the via including sidewalls;
depositing a first electrically conductive material in the via to form a layer of the first electrically conductive material, wherein the layer of first electrically conductive material is in contact with the sidewalls of the via;
after forming the layer of first electrically conductive material, depositing a second electrically conductive material to form a layer of the second electrically conductive material, wherein the layer of second electrically conductive material is in contact with the sidewalls of the via and a top surface of the dielectric layer;
removing a first portion of the layer of the second electrically conductive material, wherein, after the first portion is removed, a second portion of the second electrically conductive material remains above the top surface of the dielectric layer; and
forming a magnetoresistive structure above the second portion of the second electrically conductive material;
wherein the top surface of the dielectric layer is perpendicular to the sidewalls of the via.

19. The method of claim 18 , wherein the first and second electrically conductive materials form a first electrical contact to the magnetoresistive structure, and the method further incudes:
forming a second electrical contact through one or more dielectric materials deposited above the magnetoresistive structure.

20. The method of claim 18 , wherein the first and second electrically conductive materials have the same composition.

Assignees

• Everspin Technologies Inc

Inventors

• Nagel Kerry Joseph
• Smith Kenneth
• Hossain Moazzem
• Aggarwal Sanjeev

Classifications

• H10P50/264

  by chemical means · CPC title

• H10P14/418

  the conductive layers comprising transition metals · CPC title

• H10W20/092

  by smoothing the dielectric parts · CPC title

• H10W20/062

  by smoothing of conductive parts, e.g. by planarisation · CPC title

• H10W20/056 Primary

  by filling conductive material into holes, grooves or trenches · CPC title