IP Library › Granted Patent US 11,011,697
Granted Patent B2
US 11,011,697 · App. 16/746,558 · Granted May 18, 2021

Faceted sidewall magnetic tunnel junction structure

Inventors: Oscar van der Straten (Guilderland Center, NY); Alexander Reznicek (Troy, NY); Praneet Adusumilli (Somerset, NJ)
Assignee: International Business Machines Corporation
H01L43/02H01L27/222H01L43/08H01L43/10H01L43/12G11C11/161
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Quick Facts
Patent No.
US 11,011,697
App. No.
16/746,558
Granted
May 18, 2021
Kind
B2
Abstract

A magnetic tunnel junction (MTJ) structure having faceted sidewalls is formed on a conductive landing pad that is present on a surface of an electrically conductive structure embedded in a dielectric material layer. No metal ions are re-sputtered onto the sidewalls of the MTJ structure during the patterning of the MTJ material stack that provides the MTJ structure. The absence of re-sputtered metal on the MTJ structure sidewalls reduces the risk of shorts.

Claims (32)

1. A structure comprising:

an electrically conductive structure embedded in a dielectric material layer and present in a magnetoresistive random access memory (MRAM) device area;

a conductive landing pad located on a surface of the electrically conductive structure;

a magnetic tunnel junction (MTJ) structure having faceted sidewalls and located on a surface of the conductive landing pad, wherein the MTJ structure has a truncated bi-cone shape;

a MTJ encapsulating dielectric layer located on the dielectric material layer and laterally surrounding the MTJ structure; and

an electrically conductive metal-containing layer located on the MTJ structure.

2. The structure of claim 1 , wherein the MTJ encapsulating dielectric layer has a topmost surface that is coplanar with a topmost surface of the MTJ structure.

3. The structure of claim 1 , wherein the MTJ structure comprises a MTJ synthetic anti-ferromagnetic (SAF) layer, a MTJ reference layer, a MTJ tunnel barrier, a MTJ free layer, and a MTJ capping layer.

4. The structure of claim 1 , wherein the MTJ structure comprises a MTJ reference layer, a MTJ tunnel barrier, a MTJ free layer, and a MTJ capping layer.

5. The structure of claim 1 , wherein the electrically conductive structure and the electrically conductive metal-containing layer are composed of copper or a copper alloy.

6. The structure of claim 1 , wherein the electrically conductive structure is composed of tungsten and the electrically conductive metal-containing layer is composed of copper or a copper alloy.

7. The structure of claim 1 , wherein at least a portion of the electrically conductive metal-containing layer is located within an opening disposed in an interconnect dielectric material that is located on the MTJ encapsulating dielectric layer.

8. The structure of claim 1 , further comprising a dielectric cap located on a topmost surface of the electrically conductive metal-containing layer.

9. The structure of claim 1 , wherein the surface of the electrically conductive structure is recessed relative to a topmost surface of the dielectric material layer, and is embedded in the dielectric material layer.

10. The structure of claim 1 , further comprising a diffusion barrier material layer separating the electrically conductive metal-containing layer from the MTJ structure.

11. The structure of claim 1 , wherein no re-sputtered metal is present on the faceted sidewalls of the MTJ structure.

12. A structure comprising:

an electrically conductive structure embedded in a dielectric material layer and present in a magnetoresistive random access memory (MRAM) device area;

a conductive landing pad located on a surface of the electrically conductive structure;

a magnetic tunnel junction (MTJ) structure having faceted sidewalls and located on a surface of the conductive landing pad;

a MTJ encapsulating dielectric layer located on the dielectric material layer and laterally surrounding the MTJ structure; and

an electrically conductive metal-containing layer located on the MTJ structure, wherein the MTJ structure contacts an entirety of the conductive landing pad and a portion of a dielectric material that is located laterally adjacent to the conductive landing pad.

13. A structure comprising:

an electrically conductive structure embedded in a dielectric material layer and present in a magnetoresistive random access memory (MRAM) device area;

a conductive landing pad located on a surface of the electrically conductive structure;

a magnetic tunnel junction (MTJ) structure having a truncated bi-cone shape located on a surface of the conductive landing pad;

a MTJ encapsulating dielectric layer located on the dielectric material layer and laterally surrounding the MTJ structure; and

an electrically conductive metal-containing layer located on the MTJ structure.

14. The structure of claim 13 , wherein the MTJ structure comprises a MTJ synthetic anti-ferromagnetic (SAF) layer, a MTJ reference layer, a MTJ tunnel barrier, a MTJ free layer, and a MTJ capping layer.

15. The structure of claim 13 , wherein the MTJ structure comprises a MTJ reference layer, a MTJ tunnel barrier, a MTJ free layer, and a MTJ capping layer.

16. The structure of claim 13 , wherein no re-sputtered metal is present on the faceted sidewalls of the MTJ structure.

17. The structure of claim 13 , wherein the MTJ structure contacts an entirety of the conductive landing pad and a portion of a dielectric material that is located laterally adjacent to the conductive landing pad.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 17, 2020
From: VAN DER STRATEN, OSCAR; REZNICEK, ALEXANDER; ADUSUMILLI, PRANEET
To: INTERNATIONAL BUSINESS MACHINES CORPORATION
Reel/Frame 051550/0276 →
Continuity (2)
Division 16124937 · Sep 7, 2018
Related Publication 20200152860A1 · May 14, 2020