Barrier metal technology for tungsten plug interconnection

• US 5,600,182 A
• Filed: 01/24/1995
• Issued: 02/04/1997
• Est. Priority Date: 01/24/1995
• Status: Expired due to Term

• Current Assignee: Bell Semiconductor, LLC (Hilco Inc. (d/b/a Hilco Global))
• Original Assignee: LSI Logic Corporation (Broadcom, Inc.)
• Inventors: Padmanabhan, Gobi R., Schinella, Richard D., Zelayeta, Joseph M.
• Primary Examiner(s): TURNER, ARCHENE A
• Application Number:
  US08/378,027
• Time in Patent Office: 742 Days
• Field of Search: 428/457, 428/469, 428/472, 428/698, 428/216, 428/336, 257/741, 257/748, 257/750, 257/751, 257/758, 257/763, 437/190, 437/192, 437/194, 437/195
• US Class Current: 257/763
• CPC Class Codes: H01L 23/5226 Via connections in a multilevel interconnection structure
• CPC Class Codes: H01L 23/53223 Additional layers associated with aluminium layers, e.g. adhesion, barrier, cladding layers
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: Y10T 428/24975 No layer or component greater than 5 mils thick
• CPC Class Codes: Y10T 428/265 1 mil or less
• CPC Class Codes: Y10T 428/31678 Of metal

Abstract

A method for producing a relatively thin titanium nitride barrier layer in an integrated circuit is presented. The titanium nitride layer may be utilized in a tungsten plug interconnection by providing a semiconductor wafer with a conducting layer covered by an insulating layer. The insulating layer is patterned and etched to form contact holes or vias. A layer of titanium is deposited on the surface of the wafer including the sidewalls and bottom of the via. A relatively thin titanium nitride layer is then formed on the titanium layer. The formation of the titanium nitride layer includes growing titanium nitride by a reaction of a nitrogen-bearing species with the titanium layer. The titanium nitride layer prevents the underlying titanium layer from reacting with the subsequent tungsten layer which is deposited on the wafer to fill the via. The tungsten layer is then etched so that the tungsten remaining forms a plug interconnection between conducting layers.

Claims

1. An integrated circuit device, comprising:

a first conducting layer having a top surface;

a titanium layer on said first conducting layer, said titanium layer having a top surface;

a titanium nitride layer in a range of 20 to 50 Angstroms thick on said titanium layer; and

a second conducting layer on said titanium nitride layer.

2. The integrated circuit device of claim 1, wherein said titanium nitride layer is approximately 40 Angstroms thick.

3. The integrated circuit device of claim 1, wherein said titanium layer is in a range of 30 to 50 Angstroms thick.

4. The integrated circuit device of claim 1, wherein said titanium nitride layer is grown by a reaction of a nitrogen-bearing species with said titanium layer.

5. The integrated circuit of claim 1, wherein said titanium layer and said titanium nitride layer have a same thickness.

6. The integrated circuit device of claim 1, further comprising an insulating layer over said first conducting layer, said insulating layer having an opening to said top surface of said first conducting layer, said opening having side and bottom surfaces, and said titanium layer is located on said side and bottom surfaces of said opening.

7. The integrated circuit device of claim 1, further comprising an insulating layer over said titanium layer, said insulating layer having an opening to said top surface of said titanium layer, said opening having side and bottom surfaces, and said titanium nitride layer is located on said titanium layer on said bottom surface of said opening.

8. The integrated circuit of claim 1, wherein said titanium nitride layer is a single layer.

9. An interconnection in an integrated circuit device, said integrated circuit device formed within and on a semiconductor substrate, said interconnection comprising:

a first conducting layer having a top surface;

an insulating layer on said first conducting layer, said insulating layer having a top surface and an opening having side and bottom surfaces;

a titanium layer on said first conducting layer at said bottom surface of said opening;

a titanium nitride layer in a range of 20 to 50 Angstroms thick on said titanium layer; and

a second conducting layer in said opening on said titanium nitride layer.

10. The interconnection of claim 9, wherein said titanium nitride layer is approximately 40 Angstroms thick.

11. The interconnection of claim 9, wherein said titanium layer is in a range of 30 to 50 Angstroms thick.

12. The interconnection of claim 9, wherein said titanium nitride layer is grown by a reaction of a nitrogen-bearing species with said titanium layer.

13. The interconnection of claim 9, wherein said titanium layer and said titanium nitride layer have a same thickness.

14. The interconnection of claim 9, wherein said titanium layer is on said top surface of said insulating layer.

15. The interconnection of claim 9, wherein said second conducting layer is tungsten.

16. The interconnection of claim 9, wherein said titanium nitride layer is a single layer.

17. The interconnection of claim 9, wherein said titanium layer is in a range of 30 to 700 Angstroms thick.

21. The interconnection of claim 17, wherein said titanium layer is approximately 100 Angstroms thick.

18. An interconnection in an integrated circuit device, said integrated circuit device formed within and on a semiconductor substrate, said interconnection comprising:

a first conducting layer having a top surface;

an insulating layer on said first conducting layer, said insulating layer having a top surface and an opening having side and bottom surfaces;

a titanium layer on said side and bottom surfaces of said opening;

a titanium nitride layer in a range of 20 to 200 Angstroms thick on said titanium layer; and

a second conducting layer in said opening on said titanium nitride layer.

19. The interconnection of claim 18, wherein said titanium nitride layer is approximately 40 Angstroms thick.

20. The interconnection of claim 18, wherein said titanium nitride layer is approximately 100 Angstroms thick.

22. The interconnection of claim 18, wherein said titanium nitride layer is grown by a reaction of a nitrogen-bearing species with said titanium layer.

23. The interconnection of claim 18, wherein said titanium layer and said titanium nitride layer have a same thickness.

24. The interconnection of claim 18, wherein said titanium layer is on said top surface of said insulating layer.

25. The interconnection of claim 18, wherein said second conducting layer is tungsten.

26. The interconnection of claim 18, wherein said titanium nitride layer is a single layer.