Ruthenium as an underlayer for tungsten film deposition

• US 7,429,402 B2
• Filed: 12/10/2004
• Issued: 09/30/2008
• Est. Priority Date: 12/10/2004
• Status: Expired due to Fees

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Chang, Mei, Shah, Kavita, Khandelwal, Amit, Ganguli, Seshadri, Gandikota, Srinivas, Moorthy, Madhu, Gelatos, Avgerinos V.
• Primary Examiner(s): Meeks; Timothy
• Assistant Examiner(s): GAMBETTA, KELLY M
• Application Number:
  US11/009,331
• Publication Number:
  US 20060128150A1
• Time in Patent Office: 1,390 Days
• Field of Search: None
• US Class Current: 427/248.1
• CPC Class Codes: C23C 16/0281 of metallic sub-layers C23C16/029 takes precedence
• CPC Class Codes: C23C 16/06 characterised by the deposition of metallic material
• CPC Class Codes: C23C 16/45525 Atomic layer deposition [ALD]
• CPC Class Codes: C23C 16/45529 specially adapted for making a layer stack of alternating different compositions or gradient compositions
• CPC Class Codes: H01L 21/28556 by chemical means, e.g. CVD, LPCVD, PECVD, laser CVD H01L21/28518 - H01L21/28537 and H01L21/28568 take precedence
• CPC Class Codes: H01L 21/28562 Selective deposition
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76846 Layer combinations
• CPC Class Codes: H01L 21/76862 Bombardment with particles, e.g. treatment in noble gas plasmas; UV irradiation
• CPC Class Codes: H01L 21/76876 for deposition from the gas phase, e.g. CVD
• CPC Class Codes: H01L 21/76877 Filling of holes, grooves or trenches, e.g. vias, with conductive material
• CPC Class Codes: Y10T 428/12771 Transition metal-base component
• CPC Class Codes: Y10T 428/12812 Diverse refractory group metal-base components: alternative to or next to each other
• CPC Class Codes: Y10T 428/12861 Group VIII or IB metal-base component
• CPC Class Codes: Y10T 428/12875 Platinum group metal-base component

Abstract

In one embodiment, a method for depositing a tungsten-containing film on a substrate is provided which includes depositing a barrier layer on the substrate, such as a titanium or tantalum containing barrier layer and depositing a ruthenium layer on the barrier layer. The method further includes depositing a tungsten nucleation layer on the ruthenium layer and depositing a tungsten bulk layer on the tungsten nucleation layer. The barrier layer, the ruthenium layer, the tungsten nucleation layer and the tungsten bulk layer are independently deposited by an ALD process, a CVD process or a PVD process, preferably by an ALD process. In some examples, the substrate is exposed to a soak process prior to depositing a subsequent layer, such as between the deposition of the barrier layer and the ruthenium layer, the ruthenium layer and the tungsten nucleation layer or the tungsten nucleation layer and the tungsten bulk layer.

Claims

1. A method for depositing a tungsten-containing layer on a substrate, comprising:

depositing a metal-containing barrier layer on the substrate;

depositing a ruthenium layer on the metal-containing layer;

depositing a tungsten nucleation layer on the ruthenium layer; and

depositing a tungsten bulk layer on the tungsten nucleation layer.

2. The method of claim 1, wherein the metal-containing layer comprises tantalum or titanium.

3. The method of claim 2, wherein the metal-containing layer is tantalum nitride deposited by atomic layer deposition.

4. The method of claim 1, wherein the ruthenium layer is deposited by an atomic layer deposition process.

5. The method of claim 4, wherein the atomic layer deposition process comprises exposing the substrate to a ruthenium precursor selected from the group consisting of bis(cyclopentadienyl)ruthenium compounds, bis(alkylcyclopentadienyl)ruthenium compounds, bis(dialkylcyclopentadienyl)ruthenium compounds, bis(pentadienyl)ruthenium compounds, bis(alkylpentadienyl)ruthenium compounds, and bis(dialkylpentadienyl)ruthenium compounds.

6. The method of claim 5, wherein the atomic layer deposition process further comprises exposing the substrate to a reagent selected from the group consisting of hydrogen, silane, disilane, diborane, oxygen, nitrous oxide, and combinations thereof.

7. The method of claim 2, wherein the ruthenium layer is exposed to a soak process prior to depositing the tungsten nucleation layer.

8. The method of claim 7, wherein the soak process comprises exposing the ruthenium layer with a soak compound for a predetermined time within a range from about 5 seconds to about 90 seconds.

9. The method of claim 8, wherein the soak compound is selected from the group consisting of hydrogen, borane, diborane, silane, disilane, trisilane, dichlorosilane, derivatives thereof, and combinations thereof.

10. The method of claim 1, wherein the tungsten nucleation layer is deposited by alternately exposing the substrate to a tungsten-containing compound and a reductant.

11. The method of claim 10, wherein the reductant is selected from the group consisting of hydrogen, silane, disilane, trisilane, dichlorosilane, borane, diborane, triethylborane, derivatives thereof, and combinations thereof.

12. The method of claim 11, wherein the tungsten nucleation layer is deposited by alternately exposing the substrate to tungsten hexafluoride with silane or diborane.

13. The method of claim 10, wherein the tungsten nucleation layer is exposed to a soak process.

14. The method of claim 13, wherein the soak process comprises a compound selected from the group consisting of hydrogen, borane, diborane, silane, disilane, trisilane, dichiorosilane, derivatives thereof, and combinations thereof.

15. The method of claim 14, wherein the bulk tungsten layer is deposited by a chemical vapor deposition process.

16. A method for depositing a tungsten-containing film on a substrate, comprising:

depositing a tantalum-containing barrier layer on the substrate by a first atomic layer deposition process;

depositing a ruthenium layer on the tantalum-containing layer by a second atomic layer deposition process;

exposing the ruthenium layer to a soak process; and

depositing a tungsten nucleation layer on the ruthenium layer by a third atomic layer deposition process.

17. The method of claim 16, wherein the first atomic layer deposition process comprises exposing the substrate to pentakis(dimethylamino)tantalum and ammonia.

18. The method of claim 16, wherein the second atomic layer deposition process comprises exposing the substrate to a ruthenium precursor selected from the group consisting of bis(cyclopentadienyl)ruthenium compounds, bis(alkylcyclopentadienyl)ruthenium compounds, bis(dialkylcyclopentadienyl)ruthenium compounds, bis(pentadienyl)ruthenium compounds, bis(alkylpentadienyl)ruthenium compounds and bis(dialkylpentadienyl)ruthenium compounds.

19. The method of claim 18, wherein the second atomic layer deposition process further comprises exposing the substrate to a reagent selected from the group consisting of hydrogen, silane, disilane, diborane, oxygen, nitrous oxide, and combinations thereof.

20. The method of claim 16, wherein the soak process comprises exposing the ruthenium layer with a soak compound for a predetermined time within a range from about 5 seconds to about 90 seconds.

21. The method of claim 20, wherein the soak compound is selected from the group consisting of hydrogen, borane, diborane, silane, disilane, trisilane, dichlorosilane, derivatives thereof, and combinations thereof.

22. The method of claim 21, wherein the third atomic layer deposition process comprises a reductant selected from the group consisting of hydrogen, silane, disilane, trisilane, dichlorosilane, borane, d iborane, triethylborane, derivatives thereof, and combinations thereof.

23. The method of claim 22, wherein the tungsten nucleation layer is deposited by alternately exposing the substrate to tungsten hexafluoride with silane or diborane.

24. The method of claim 16, wherein the tungsten nucleation layer is exposed to a second soak process.

25. The method of claim 24, wherein the second soak process comprises a compound selected from the group consisting of hydrogen, borane, diborane, silane, disilane, trisilane, dichlorosilane, derivatives thereof, and combinations thereof.

26. The method of claim 25, wherein a bulk tungsten layer is deposited on the tungsten nucleation layer by a chemical vapor deposition process.

27. A method for depositing a tungsten-containing film on a substrate, comprising:

depositing a ruthenium layer on the substrate by a first atomic layer deposition process;

exposing the ruthenium layer to a soak process comprising flowing a soak compound for a predetermined time with a range from about 5 seconds to about 90 seconds, wherein the soak compound is selected from the group consisting of hydrogen, borane, diborane, silane, disilane, trisilane, dichlorosilane, derivatives thereof, and combinations thereof; and

depositing a tungsten nucleation layer on the ruthenium layer by a second atomic layer deposition process.

28. A method of forming a ruthenium layer on a substrate for use in integrated circuit fabrication, comprising:

depositing a barrier layer on a substrate surface by a first deposition process, wherein the barrier layer is selected from the group consisting of tantalum, tantalum nitride, tantalum silicon nitride, titanium, titanium nitride, titanium silicon nitride tungsten, tungsten nitride, and combinations thereof

depositing the ruthenium layer on the barrier layer by a first ALD process, comprising sequentially exposing the barrier layer to a ruthenium-containing compound and a reagent; and

depositing a tungsten layer on the ruthenium layer by a second ALD process, comprising sequentially exposing the ruthenium layer to a tungsten-containing compound and a reductant.