Via for semiconductor device and method

Patent metadata

Field	Value
Publication number	US-12315809-B2
Application number	US-202318358803-A
Country	US
Kind code	B2
Filing date	Jul 25, 2023
Priority date	Aug 25, 2020
Publication date	May 27, 2025
Grant date	May 27, 2025

Abstract

A structure includes a first conductive feature in a first dielectric layer; a second dielectric layer over the first dielectric layer; and a second conductive feature extending through the second dielectric layer to physically contact the first conductive feature, wherein the second conductive feature includes a metal adhesion layer over and physically contacting the first conductive feature; a barrier layer extending along sidewalls of the second dielectric layer; and a conductive filling material extending over the metal adhesion layer and the barrier layer, wherein a portion of the conductive filling material extends between the barrier layer and the metal adhesion layer.

First claim

What is claimed is:

1. A method comprising:
forming an insulating layer over a conductive feature;
forming a metal mask over the insulating layer;
etching the insulating layer using the metal mask to form an opening that exposes a surface of the conductive feature;
selectively depositing an adhesion layer on the exposed surface of the conductive feature;
selectively depositing a sacrificial layer on the adhesion layer;
selectively depositing a barrier layer on surfaces of the insulating layer and the metal mask;
performing a removal process to remove the sacrificial layer, wherein the removal process densifies the barrier layer; and
depositing a conductive fill material in the opening.

2. The method of claim 1 , wherein the adhesion layer comprises cobalt.

3. The method of claim 1 , wherein the removal process comprises an anneal.

4. The method of claim 1 further comprising performing a planarization process after depositing the conductive fill material, wherein the planarization process removes the metal mask.

5. The method of claim 1 , wherein the conductive fill material extends from a bottom-most surface of the barrier layer to a top surface of the adhesion layer.

6. The method of claim 1 , wherein the conductive fill material physically contacts the insulating layer.

7. The method of claim 1 , wherein the barrier layer is free of the adhesion layer.

8. The method of claim 1 , wherein the sacrificial layer comprises benzotriazole (BTA).

9. A method comprising:
forming a conductive feature in a first dielectric layer;
depositing a second dielectric layer over the first dielectric layer;
forming a patterned mask on the second dielectric layer;
using the patterned mask, etching an opening in the second dielectric layer that exposes a surface of the conductive feature;
depositing an adhesion layer on the exposed surface of the conductive feature, wherein the second dielectric layer is free of the adhesion layer;
after depositing the adhesion layer, depositing a barrier layer on the patterned mask and on sidewalls of the opening, wherein a top surface of the adhesion layer is free of the barrier layer, wherein the barrier layer comprises nitrogen;
performing a plasma treatment process on the barrier layer, wherein the plasma treatment process removes a portion of the nitrogen from the barrier layer; and
depositing a conductive material on the adhesion layer, wherein the conductive material fills the opening.

10. The method of claim 9 further comprising, before depositing the conductive material on the adhesion layer, depositing a sacrificial material on the adhesion layer.

11. The method of claim 10 , wherein the plasma treatment process removes the sacrificial material.

12. The method of claim 9 further comprising depositing a third dielectric layer over the first dielectric layer before depositing the second dielectric layer.

13. The method of claim 12 , wherein the conductive material physically contacts a sidewall of the third dielectric layer.

14. The method of claim 9 , wherein the conductive feature is free of the barrier layer.

15. The method of claim 12 , wherein a thickness of the barrier layer is less than a thickness of the third dielectric layer.

16. A method comprising:
depositing an etch stop layer over a metal line;
depositing a dielectric layer over the etch stop layer;
forming an opening through the etch stop layer and the dielectric layer, wherein the opening exposes the metal line;
depositing a first adhesion material in the opening, wherein the first adhesion material selectively forms on the metal line;
depositing a hydrophobic material in the opening, wherein the hydrophobic material covers the first adhesion material;
depositing a metal nitride material in the opening, wherein the metal nitride material selectively bonds to the dielectric layer more than the metal nitride material bonds to the hydrophobic material;
removing the hydrophobic material; and
depositing a conductive material in the opening.

17. The method of claim 16 , wherein a thickness of the first adhesion material is less than a thickness of the etch stop layer.

18. The method of claim 16 , wherein the hydrophobic material forms chelation bonds with the first adhesion material.

19. The method of claim 16 , wherein the conductive material separates the metal nitride material from the first adhesion material.

20. The method of claim 16 further comprising, after removing the hydrophobic material, depositing a second adhesion layer in the opening.

Assignees

• Taiwan Semiconductor Mfg Co Ltd

Inventors

• Kuo Chia-Pang
• Chang Chih-Yi
• Hsieh Ming-Hsiao
• Chan Wei-Hsiang
• Lee Ya-Lien
• Huang Chien Chung
• Lin Chun-Chieh
• Su Hung-Wen

Classifications

• H10W20/4437

  the principal metal being a transition metal · CPC title

• H10W20/082

  the openings being tapered via holes · CPC title

• H10W20/056

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

• H10W20/035

  combinations of barrier, adhesion or liner layers, e.g. multi-layered barrier layers · CPC title

• H10W20/0765

  the thin functional dielectric layers being temporary, e.g. sacrificial layers · CPC title