Method to deposit CVD ruthenium

• US 9,938,622 B2
• Filed: 02/17/2016
• Issued: 04/10/2018
• Est. Priority Date: 11/09/2012
• Status: Active Grant

• Current Assignee: Applied Materials Incorporated
• Original Assignee: Applied Materials Incorporated
• Inventors: Ha, Tae Hong, Yu, Sang Ho, Park, Kiejin
• Primary Examiner(s): Chen, Bret P
• Application Number:
  US15/045,667
• Publication Number:
  US 20160160350A1
• Time in Patent Office: 783 Days
• CPC Class Codes: C23C 16/0281 of metallic sub-layers C23C16/029 takes precedence
• CPC Class Codes: C23C 16/16 from metal carbonyl compounds
• CPC Class Codes: C23C 16/18 from metallo-organic compounds
• CPC Class Codes: C23C 16/46 characterised by the method used for heating the substrate C23C16/48, C23C16/50 take precedence
• CPC Class Codes: C23C 16/505 using radio frequency discharges
• CPC Class Codes: C23C 16/513 using plasma jets
• CPC Class Codes: C23C 28/322 only coatings of metal elements only
• CPC Class Codes: C23C 28/34 including at least one inorganic non-metallic material layer, e.g. metal carbide, nitride, boride, silicide layer and their mixtures, enamels, phosphates and sulphates
• 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 21/76841 Barrier, adhesion or liner layers
• CPC Class Codes: H01L 21/76873 for electroplating
• CPC Class Codes: H01L 2221/1089 Stacks of seed layers

Abstract

Methods for depositing ruthenium by a PECVD process are described herein. Methods for depositing ruthenium can include positioning a substrate in a processing chamber, the substrate having a barrier layer formed thereon, heating and maintaining the substrate at a first temperature, flowing a first deposition gas into a processing chamber, the first deposition gas comprising a ruthenium containing precursor, generating a plasma from the first deposition gas to deposit a first ruthenium layer over the barrier layer, flowing a second deposition gas into the processing chamber to deposit a second ruthenium layer over the first ruthenium layer, the second deposition gas comprising a ruthenium containing precursor, depositing a copper seed layer over the second ruthenium layer and annealing the substrate at a second temperature.

Claims

1. A method for depositing ruthenium, comprising:

heating and maintaining a substrate at a first temperature in a processing chamber, wherein the substrate has a barrier layer formed thereon;

flowing a first deposition gas into the processing chamber to deposit a first ruthenium layer on the barrier layer using a first chemical vapor deposition method, wherein the first deposition gas is selected from the group consisting of Ru(C₅H₅)₂ (bis(cyclopentadienyl)ruthenium), Ru₃(CO)₁₂ (dodecacarbonyl triruthenium), and combinations thereof; and

flowing a second deposition gas into the processing chamber to deposit a second ruthenium layer on the first ruthenium layer using a second chemical vapor deposition method that is different from the first chemical vapor deposition method, wherein the second deposition gas is selected from the group consisting of Ru(C₅H₅)₂ (bis(cyclopentadienyl)ruthenium), Ru₃(CO)₁₂ (dodecacarbonyl triruthenium), and combinations thereof, and the second deposition gas is different from the first deposition gas.

2. The method of claim 1, wherein the first chemical vapor deposition method is a plasma-enhanced chemical vapor deposition (PECVD) method and the second chemical vapor deposition method is performed in a plasma-free environment.

3. The method of claim 1, wherein the first temperature is between 150°

C. and 350°

C.

4. The method of claim 1, wherein the first ruthenium layer is from 3 Å

to 7 Å

thick.

5. The method of claim 1, wherein the second ruthenium layer is from 10 Å

to 45 Å

thick.

6. The method of claim 1, wherein the barrier layer comprises tantalum (Ta) and tantalum nitride (TaN).

7. The method of claim 1, wherein the barrier layer has one or more copper features formed underneath.

8. The method of claim 1, wherein the first deposition gas further comprises H₂, NH₃, Ar, N₂, He or combinations thereof.

9. A method for depositing ruthenium, comprising:

heating and maintaining a substrate at a first temperature in a processing chamber, wherein the substrate has a barrier layer formed thereon;

flowing a first deposition gas into the processing chamber, the first deposition gas is selected from the group consisting of Ru(C₅H₅)₂ (bis(cyclopentadienyl)ruthenium), Ru₃(CO)₁₂ (dodecacarbonyl triruthenium), and combinations thereof;

generating a plasma from the first deposition gas to deposit a first ruthenium layer over the barrier layer;

flowing a second deposition gas into the processing chamber to deposit a second ruthenium layer on the first ruthenium layer by a chemical vapor deposition (CVD) method in a plasma-free environment, wherein the second deposition gas is selected from the group consisting of Ru(C₅H₅)₂ (bis(cyclopentadienyl)ruthenium), Ru₃(CO)₁₂ (dodecacarbonyl triruthenium), and combinations thereof, and the second deposition gas is different from the first deposition gas;

depositing a copper seed layer over the second ruthenium layer; and

annealing the substrate at a second temperature.

10. The method of claim 9, wherein the first temperature is between 150°

C. and 350°

C.

11. The method of claim 9, wherein the first deposition gas further comprises H₂, NH₃, Ar, N₂, He or combinations thereof.

12. The method of claim 9, wherein the first ruthenium layer is from 3 Å

to 7 Å

thick.

13. The method of claim 9, wherein the second ruthenium layer is from 10 Å

to 52 Å

thick.

14. The method of claim 9, wherein the plasma is generated from an RF source with a power between 50 W and 1000 W.

15. The method of claim 9, wherein the barrier layer comprises tantalum (Ta) and tantalum nitride (TaN).

16. A method for depositing ruthenium, comprising:

heating a substrate in a processing chamber, the substrate having a barrier layer formed thereon;

depositing a first ruthenium layer on the barrier layer from a first deposition gas using a first chemical vapor deposition method, wherein the first deposition gas is selected from the group consisting of Ru(C₅H₅)₂ (bis(cyclopentadienyl)ruthenium), Ru₃(CO)₁₂ (dodecacarbonyl triruthenium), and combinations thereof;

depositing a second ruthenium layer on the first ruthenium layer from a second deposition gas using a second chemical vapor deposition method in a plasma-free environment, wherein the second deposition gas is selected from the group consisting of Ru(C₅H₅)₂ (bis(cyclopentadienyl)ruthenium), Ru₃(CO)₁₂ (dodecacarbonyl triruthenium), and combinations thereof, and the second deposition gas is different from the first deposition gas;

depositing a copper layer on the second ruthenium layer; and

annealing the substrate.

17. The method of claim 16, wherein the first chemical vapor deposition method is a plasma-enhanced chemical vapor deposition (PECVD) method.

18. The method of claim 17, wherein the PECVD method uses an RF source with a power between 50 W and 1000 W.

19. The method of claim 16, wherein the first ruthenium layer is from 3 Å

to 7 Å

thick.

20. The method of claim 16, wherein the second ruthenium layer is from 10 Å

to 45 Å

thick.