Multiple seed layers for interconnects

• US 7,282,445 B2
• Filed: 01/17/2007
• Issued: 10/16/2007
• Est. Priority Date: 10/02/1999
• Status: Expired due to Term

• Current Assignee: Uri Cohen
• Original Assignee: Uri Cohen
• Inventors: Cohen, Uri
• Primary Examiner(s): SMITH, BRADLEY
• Application Number:
  US11/654,478
• Publication Number:
  US 20070117379A1
• Time in Patent Office: 272 Days
• Field of Search: 438/637, 438/687, 257/E21.585
• US Class Current: 438/687
• CPC Class Codes: H01L 21/76843 formed in openings in a dielectric
• CPC Class Codes: H01L 21/76873 for electroplating
• CPC Class Codes: H01L 2221/1089 Stacks of seed layers

Abstract

One embodiment of the present invention is a method for depositing two or more seed layers over a substrate, the substrate includes a patterned insulating layer which comprises at least one opening surrounded by a field, the at least one opening and the field being ready for depositing one or more seed layers, the at least one opening having sidewalls and bottom, and the method including: (a) providing a CVD chamber capable of depositing a conformal (i.e., continuous) seed layer over the sidewalls and bottom of the at least one opening; (b) providing a PVD chamber capable of depositing a PVD seed layer over the substrate; (c) configuring an automatic controller with recipe information, the recipe information including deposition sequence, process and timing parameters for operation of the CVD and the PVD chambers; (d) operating the automatic controller in accordance with the recipe information to cause the CVD chamber to deposit a conformal (i.e., continuous) first seed layer over the sidewalls and bottom of the at least one opening, the first seed layer having a thickness less than about 200 Å over the field; (e) operating the controller in accordance with the recipe information to cause the PVD chamber to deposit a second seed layer over the first seed layer, the second seed layer having a thickness greater than about 100 Å over the field; and (f) operating the controller in accordance with the recipe information to stop the deposition of the second seed layer prior to sealing the at least one opening, thereby leaving enough room for electroplating inside the at least one opening.

Claims

1. A method for depositing two or more seed layers over a substrate, the substrate includes a patterned insulating layer which comprises at least one opening surrounded by a field, the at least one opening and the field being ready for depositing one or more seed layers, the at least one opening having sidewalls and bottom, and the method comprising:

a) providing a deposition chamber capable of depositing a continuous seed layer over the sidewalls and bottom of the at least one opening;

b) providing a PVD chamber capable of depositing a PVD seed layer over the substrate;

c) configuring an automatic controller with recipe information, the recipe information including deposition sequence, process and timing parameters for operation of the deposition chamber and the PVD chamber;

d) operating the automatic controller in accordance with the recipe information to deposit in the deposition chamber a continuous seed layer over the sidewalls and bottom of the at least one opening, the continuous seed layer having a thickness greater than about 50Å

over the field;

e) operating the controller in accordance with the recipe information to deposit in the PVD chamber a PVD seed layer over the substrate, the PVD seed layer having a thickness greater than about 250 Å

over the field, and wherein the substrate is not exposed to air atmosphere between depositions of the two seed layers; and

f) operating the controller in accordance with the recipe information to stop the deposition of the continuous seed layer and the PVD seed layer prior to sealing the at least one opening, thereby leaving enough room for electroplating inside the at least one opening.

2. The method of claim 1 further comprising depositing the continuous seed layer using a chemical vapor deposition (CVD) technique.

3. The method of claim 1 further comprising depositing the continuous seed layer using a physical vapor deposition (PVD) technique.

4. The method of claim 1 wherein at least one of the seed layers comprises a material selected from a group consisting of Cu, Ag, or alloys comprising one or more of these metals.

5. The method of claim 1 further comprising operating the controller in accordance with the recipe information to perform the deposition of the PVD seed layer before the deposition of the continuous seed layer.

6. The method of claim 1 further comprising operating the controller in accordance with the recipe information to perform the deposition of the continuous seed layer before the deposition of the PVD seed layer.

7. The method of claim 1 wherein said substrate includes at least one barrier layer deposited over the field and inside surfaces of the at least one opening prior to the deposition of the seed layers.

8. A method for depositing in one PVD chamber two or more PVD seed layers over a substrate, the substrate including a patterned insulating layer which comprises at least one opening surrounded by a field, the at least one opening and the field being ready for depositing one or more seed layers, the at least one opening having sidewalls and bottom, and the method comprising:

a) providing a PVD chamber capable of depositing a continuous seed layer over the sidewalls and bottom of the at least one opening;

b) configuring an automatic controller with recipe information, the recipe information including deposition sequence, process and timing parameters for operation of the PVD chamber;

c) operating the automatic controller in response to the recipe information to deposit in the PVD chamber, using a first set of deposition parameters, a continuous seed layer over the sidewalls and bottom of the at least one opening, the continuous seed layer having a thickness greater than about 50 Å

over the field;

d) operating the controller in response to the recipe information to deposit in the PVD chamber, using a second set of deposition parameters, another PVD seed layer over the substrate, wherein said second set of deposition parameters includes at least one deposition parameter which is different than in the first set of deposition parameters, and wherein the combined seed layers provide a low electrical resistance path over the field to enable uniform plating across the substrate; and

e) operating the controller in response to the recipe information to stop the deposition of the seed layers prior to sealing the at least one opening, thereby leaving enough room for electroplating inside the at least one opening.

9. The method of claim 8 wherein at least one of the seed layers comprises a material selected from a group consisting of Cu, Ag, or alloys comprising one or more of these metals.

10. The method of claim 8 further comprising operating the controller in accordance with the recipe information to perform the deposition of said another PVD seed layer before the deposition of said continuous seed layer.

11. The method of claim 8 further comprising operating the controller in accordance with the recipe information to perform the deposition of said continuous seed layer before the deposition of said another PVD seed layer.

12. The method of claim 8 wherein said substrate includes at least one barrier layer deposited over the field and inside surfaces of the at least one opening prior to the deposition of the seed layers.

13. A method for depositing in one CVD chamber two or more seed layers over a substrate, the substrate including at least one insulating layer which comprises at least one opening surrounded by a field, the at least one opening and the field being ready for depositing one or more seed layers, the at least one opening having sidewalls and bottom, and the method comprising:

a) providing a CVD chamber capable of depositing a more conformal seed layer and a less conformal seed layer over the sidewalls and bottom of the at least one opening;

b) configuring an automatic controller with recipe information, the recipe information including deposition sequence, process and timing parameters for operation of the CVD chamber;

c) operating the automatic controller in response to the recipe information to deposit in the CVD chamber, using a first set of deposition parameters, a more conformal seed layer over the sidewalls and bottom of the at least one opening;

d) operating the controller in response to the recipe information to deposit in the CVD chamber, using a second set of deposition parameters, a less conformal seed layer over the substrate, wherein said second set of deposition parameters includes at least one deposition parameter which is different than in the first set of deposition parameters; and

e) operating the controller in response to the recipe information to stop the deposition of the seed layers prior to sealing the openings, thereby leaving enough room for electroplating inside the at least one opening.

14. The method of claim 13 wherein at least one of the seed layers comprises one or more materials selected from a group consisting of Cu, Ag, or alloys comprising one or more of these metals.

15. The method of claim 13 further comprising operating the controller in accordance with the recipe information to perform the deposition of said more conformal seed layer before the deposition of said less conformal seed layer.

16. The method of claim 13 further comprising operating the controller in accordance with the recipe information to perform the deposition of said less conformal seed layer before the deposition of said more conformal seed layer.

17. The method of claim 13 wherein said substrate includes at least one barrier layer deposited over the field and inside surfaces of the at least one opening prior to the deposition of the seed layers.

18. A method for depositing two or more seed layers over a substrate, the substrate includes a patterned insulating layer which comprises at least one opening surrounded by a field, the at least one opening and the field being ready for depositing one or more seed layers, the at least one opening having sidewalls, and the method comprising:

a) utilizing a CVD chamber capable of depositing a CVD seed layer over the sidewalls of the at least one opening;

b) utilizing a PVD chamber capable of depositing a PVD seed layer over the substrate;

c) configuring an automatic controller with recipe information, the recipe information including deposition sequence, process and timing parameters for operation of the CVD chamber and the PVD chamber;

d) operating the automatic controller in accordance with the recipe information to cause the CVD chamber to deposit a CVD first seed layer over the field and the sidewalls of the at least one opening;

e) operating the controller in accordance with the recipe information to deposit in the PVD chamber a second seed layer over the first seed layer; and

f) operating the controller in accordance with the recipe information to stop the deposition of the first and second seed layers prior to sealing the at least one opening, thereby leaving enough room for electroplating inside the at least one opening.

19. The method of claim 18 wherein at least one of said first and second seed layers comprises a material selected from a group consisting of Cu, Ag, or alloys comprising one or more of these metals.

20. The method of claim 19 wherein the first seed layer has a thickness of less than about 100 Å

over the field.

21. A method for depositing two or more seed layers over a substrate, the substrate includes a patterned insulating layer which comprises at least one opening surrounded by a field, the at least one opening having sidewalls, the at least one opening and the field being ready for depositing one or more seed layers, and the method comprising:

a) utilizing a PVD chamber capable of depositing a PVD seed layer over the substrate;

b) utilizing a CVD chamber capable of depositing a CVD seed layer over the sidewalls of the at least one opening;

c) configuring an automatic controller with recipe information, the recipe information including deposition sequence, process and timing parameters for operation of the PVD chamber and the CVD chamber;

d) operating the automatic controller in accordance with the recipe information to deposit in the PVD chamber a first seed layer over the field and inside surfaces of the at least one opening, the first seed layer having a thickness greater than about 250 Å

over the field;

e) operating the controller in accordance with the recipe information to deposit in the CVD chamber a second seed layer over the first seed layer, wherein the combined seed layers provide a low electrical resistance path over the field to enable uniform plating across the substrate; and

f) operating the controller in accordance with the recipe information to stop the deposition of the first and second seed layers prior to sealing the at least one opening, thereby leaving enough room for electroplating inside the at least one opening, and wherein at least one of said first and second seed layers comprises a material selected from a group consisting of Cu, Ag, or alloys comprising one or more of these metals.

22. The method of claim 21 wherein the second seed layer has a thickness of less than about 100 Å

over the field.