Method of forming a low resistance multi-layered TiN film with superior barrier property using poison mode cycling

• US 20030054628A1
• Filed: 09/17/2001
• Published: 03/20/2003
• Est. Priority Date: 09/17/2001
• Status: Abandoned Application

• Current Assignee: Chartered Semiconductor Manufacturing Incorporated (GlobalFoundries, Inc.)
• Original Assignee: Chartered Semiconductor Manufacturing Incorporated (GlobalFoundries, Inc.)
• Inventors: Chang, Fu, Chih, Johnny Kuei, Leng, Xavier Seah Teo
• Application Number:
  US09/953,545
• Publication Number:
  US 20030054628A1
• Time in Patent Office: Days
• US Class Current: 438/622
• CPC Class Codes: H01L 21/2855 by physical means, e.g. sputtering, evaporation H01L21/28518 - H01L21/28537 and H01L21/28568 take precedence
• CPC Class Codes: H01L 21/76846 Layer combinations
• CPC Class Codes: H01L 2221/1078 Multiple stacked thin films not being formed in openings in dielectrics

Abstract

A new method of forming a robust titanium nitride barrier layer by PVD is described. Semiconductor device structures are provided in and on a semiconductor substrate. The semiconductor device structures are covered with an insulating layer. A via is opened through the insulating layer to one of the underlying semiconductor device structures. A titanium nitride barrier layer having a discontinuous grain structure is deposited within the via wherein the titanium nitride barrier layer comprises alternating layers of titanium nitride and titanium containing a trace of nitrogen. A metal layer is deposited overlying the titanium nitride barrier layer wherein the discontinuous grain structure of the titanium nitride barrier layer prevents diffusion from the metal layer into the insulating layer to complete formation of a robust titanium nitride barrier layer in the fabrication of an integrated circuit device.

Claims

1. A method of metallization in the fabrication of an integrated circuit device comprising:

providing semiconductor device structures in and on a substrate;

covering said semiconductor device structures with an insulating layer;

opening a via through said insulating layer to one of said underlying semiconductor device structures;

conformally depositing a titanium nitride barrier layer having a discontinuous grain structure within said via; and

depositing a metal layer overlying said titanium nitride barrier layer to complete said metallization in the fabrication of said integrated circuit device.

2. The method according to claim 1 wherein said semiconductor device structures include silicided gate electrodes and associated silicided source and drain regions.

3. The method according to claim 1 wherein said semiconductor device structures include silicided gate electrodes and associated silicided source and drain regions and lower level metallization.

4. The method according to claim 1 wherein said step of depositing said titanium nitride barrier layer comprises within a single sputtering chamber:

turning on a N₂ gas flow and thereby depositing a first layer of TiN within said via opening;

turning off said N₂ gas flow and thereby depositing a first titanium layer containing a trace of nitrogen overlying said first TiN layer; and

continuing a cycle of alternatingly turning on and off said N2 gas flow to form alternating layers of TiN and titanium containing a trace of nitrogen.

5. The method according to claim 4 wherein said during said step of turning on said N₂ gas flow, radio frequency power of a first rate is applied and wherein during said step of turning off said N₂ gas flow, radio frequency power of a second rate higher than said first rate is applied.

6. The method according to claim 5 wherein said first rate is about 6.5 kilowatts and wherein said second rate is about 8 kilowatts.

7. The method according to claim 1 wherein said discontinuous grain structure of said titanium nitride barrier layer prevents diffusion from said metal layer into said insulating layer.

8. The method according to claim 1 wherein said metal layer comprises tungsten.

9. The method according to claim 1 wherein said metal layer comprises copper.

10. The method according to claim 1 wherein said metal layer comprises AlCu.

11. A method of metallization in the fabrication of an integrated circuit device comprising:

providing semiconductor device structures in and on a substrate;

covering said semiconductor device structures with an insulating layer;

opening a via through said insulating layer to one of said underlying semiconductor device structures;

conformally depositing a titanium nitride barrier layer having a discontinuous grain structure within said via wherein said titanium nitride barrier layer comprises alternating layers of titanium nitride and titanium containing a trace of nitrogen; and

depositing a metal layer overlying said titanium nitride barrier layer to complete said metallization in the fabrication of said integrated circuit device.

12. The method according to claim 11 wherein said semiconductor device structures include silicided gate electrodes and associated silicided source and drain regions.

13. The method according to claim 11 wherein said semiconductor device structures include silicided gate electrodes and associated silicided source and drain regions and lower level metallization.

14. The method according to claim 11 wherein said step of depositing said titanium nitride barrier layer comprising alternating layers of titanium nitride and titanium containing a trace of nitrogen and comprises within a single sputtering chamber:

turning on a N₂ gas flow and thereby depositing a layer of titanium nitride; and

turning off said N₂ gas flow and thereby depositing a titanium layer containing a trace of nitrogen.

15. The method according to claim 14 wherein said during said step of turning on said N₂ gas flow, radio frequency power of a first rate is applied and wherein during said step of turning off said N₂ gas flow, radio frequency power of a second rate higher than said first rate is applied.

16. The method according to claim 15 wherein said first rate is about 6.5 kilowatts and wherein said second rate is about 8 kilowatts.

17. The method according to claim 11 wherein said discontinuous grain structure of said titanium nitride barrier layer prevents diffusion from said metal layer into said insulating layer.

18. The method according to claim 12 wherein said metal layer is selected from the group containing:

tungsten, copper, and AlCu.

19. A method of metallization in the fabrication of an integrated circuit device comprising:

providing semiconductor device structures in and on a substrate;

covering said semiconductor device structures with an insulating layer;

opening a via through said insulating layer to one of said underlying semiconductor device structures;

conformally depositing a titanium nitride barrier layer having a discontinuous grain structure within said via wherein said titanium nitride barrier layer comprises alternating layers of titanium nitride and titanium containing a trace of nitrogen; and

depositing a metal layer overlying said titanium nitride barrier layer wherein said discontinuous grain structure of said titanium nitride barrier layer prevents diffusion from said metal layer into said insulating layer to complete said metallization in the fabrication of said integrated circuit device.

20. The method according to claim 19 wherein said semiconductor device structures include silicided gate electrodes and associated silicided source and drain regions.

21. The method according to claim 19 wherein said semiconductor device structures include silicided gate electrodes and associated silicided source and drain regions and lower level metallization.

22. The method according to claim 19 wherein said step of depositing said titanium nitride barrier layer comprising alternating layers of titanium nitride and titanium containing a trace of nitrogen and comprises within a single sputtering chamber:

turning on a N₂ gas flow and thereby depositing a layer of titanium nitride; and

turning off said N₂ gas flow and thereby depositing a titanium layer containing a trace of nitrogen.

23. The method according to claim 22 wherein said during said step of turning on said N₂ gas flow, radio frequency power of a first rate is applied and wherein during said step of turning off said N₂ gas flow, radio frequency power of a second rate higher than said first rate is applied.

24. The method according to claim 22 wherein said first rate is about 6.5 kilowatts and wherein said second rate is about 8 kilowatts.

25. The method according to claim 19 wherein said metal layer is selected from the group containing:

tungsten, copper, and AlCu.