Method of sealing wafer backside for full-face electrochemical plating

• US 6,855,037 B2
• Filed: 07/20/2001
• Issued: 02/15/2005
• Est. Priority Date: 03/12/2001
• Status: Expired due to Fees

• Current Assignee: Novellus Systems Incorporated (Lam Research Corporation)
• Original Assignee: ASM NuTool, Inc. (ASM International NV)
• Inventors: Ashjaee, Jalal, Talieh, Homayoun, Basol, Bulent, Volodarsky, Konstantin
• Primary Examiner(s): NGUYEN, GEORGE BINH MINH
• Application Number:
  US09/910,686
• Publication Number:
  US 20020127956A1
• Time in Patent Office: 1,306 Days
• Field of Search: 451287-289, 451/388, 451/398, 451/41, 451/57, 451/67
• US Class Current: 451/57
• CPC Class Codes: B24B 37/30 for single side lapping of plane surfaces
• CPC Class Codes: C25D 17/001 Apparatus specially adapted for electrolytic coating of wafers, e.g. semiconductors or solar cells
• CPC Class Codes: C25D 17/06 Suspending or supporting devices for articles to be coated
• CPC Class Codes: H01L 21/6704 for wet cleaning or washing
• CPC Class Codes: H01L 21/6715 Apparatus for applying a liquid, a resin, an ink or the like H01L21/67126 takes precedence
• CPC Class Codes: H01L 21/6838 with gripping and holding devices using a vacuum; Bernoulli devices

Abstract

The present invention provides a wafer carrier that includes an opening, which in one embodiment is a plurality of holes, disposed along the periphery of the wafer carrier. A gas emitted through the holes onto a peripheral back edge of the wafer assists in preventing the processing liquids and contaminants resulting therefrom from reaching the inner region of the base and the backside inner region of the wafer. In another embodiment, a plurality of concentric sealing members are used to prove a better seal, and the outer seal is preferably independently movable to allow cleaning of a peripheral backside of the wafer to occur while the wafer is still attached to the wafer carrier.

Claims

1. A method of processing a frontside of a substrate using a processing solution while holding the substrate with a substrate holder using vacuum comprising the steps of:

attaching the substrate to the substrate holder using the vacuum, the substrate holder including an inner sealing member, the inner sealing member providing a seal for a backside region of the substrate;

providing another seal on the backside of the substrate using an outer sealing member that is disposed outside of the seal provided by the inner sealing member, the step of providing including the step of moving the outer sealing member to the backside region of the substrate;

processing the frontside of the substrate using the processing solution while the inner sealing member and the outer sealing member provide the seal and the another seal, respectively thereby substantially preventing the processing solution from reaching the backside region;

removing the another seal, the step of removing the another seal including the step of moving the outer sealing member away from the backside of the substrate upon completion of the processing of the frontside of the substrate; and

cleaning a peripheral backside of the substrate using a cleaning solution.

2. The method according to claim 1 wherein the step of processing the frontside of the substrate performs chemical mechanical polishing of the frontside of the substrate using a pad, and wherein the frontside of the substrate and the pad are in contact with and move relative to each other.

3. The method according to claim 1 wherein the processing solution is a slurry.

4. The method according to claim 1 wherein the step of processing the frontside of the substrate performs electrochemical deposition of a conductor using an electrolyte as the processing solution.

5. The method according to claim 4 wherein the step of processing uses a pad for polishing of the substrate.

6. The method according to claim 1 wherein the step of processing the frontside of the substrate performs electropolishing of the frontside of the substrate using a pad for polishing of the substrate.

7. The method according to claim 1 wherein the seal provided by the vacuum during the step of attaching holds the substrate to the substrate holder without a clamp during the processing, and thereby provides for full face processing of the frontside of the substrate.

8. The method according to claim 7 wherein the seal provided by the vacuum of the inner sealing member and the another seal provided by the outer sealing member solely prevent lateral movement of the substrate during processing relative to the substrate holder.

9. The method according to claim 8 wherein the step of processing the frontside of the substrate performs chemical mechanical polishing of the frontside of the substrate using a pad, and wherein the frontside of the substrate and the pad are in contact with and move relative to each other.

10. The method according to claim 9 wherein the processing solution is a slurry.

11. The method according to claim 8 wherein the step of processing the frontside of the substrate performs electrochemical deposition of a conductor using an electrolyte as the processing solution.

12. The method according to claim 11 wherein the step of processing uses a pad for polishing of the substrate.

13. The method according to claim 8 wherein the step of processing the frontside of the substrate performs electropolishing of the frontside of the substrate using a pad for polishing of the substrate.

14. The method according to claim 7 wherein the substrate holder does not include a carrier ring that operates to prevent lateral movement of an edge of the substrate beyond the carrier ring.

15. The method according to claim 14 wherein the step of processing the frontside of the substrate performs chemical mechanical polishing of the frontside of the substrate using a pad, and wherein the frontside of the substrate and the pad are in contact with and move relative to each other.

16. The method according to claim 15 wherein the processing solution is a slurry.

17. The method according to claim 14 wherein the step of processing the frontside of the substrate performs electrochemical deposition of a conductor using an electrolyte as the processing solution.

18. The method according to claim 17 wherein the step of processing uses a pad for polishing of the substrate.

19. The method according to claim 14 wherein the step of processing the frontside of the substrate performs electropolishing of the frontside of the substrate using a pad for polishing of the substrate.

20. The method according to claim 1 wherein only the seal of the inner sealing member provided by the vacuum holds the substrate to the substrate holder during the step of cleaning.

21. The method according to claim 20 wherein the seal provided by the vacuum of the inner sealing member and the another seal provided by the outer sealing member solely prevent lateral movement of the substrate during processing relative to the substrate holder and wherein the step of processing performs full face processing of the frontside of the substrate.

22. The method according to claim 20 wherein the substrate holder does not include a carrier ring that operates to prevent lateral movement of an edge of the substrate beyond the carrier ring and wherein the step of processing performs full face processing of the frontside of the substrate.

23. The method according to claim 20 wherein the inner sealing member is an o-ring and the outer sealing member is another o-ring.

24. The method according to claim 23 wherein the o-ring is an elastomeric o-ring having a durometer rating of less than 70.

25. The method according to claim 24 wherein the elastomeric o-ring is an elastomeric hollow o-ring that has a durometer rating within the range of 30-50.

26. The method according to claim 1 further including a spin drying step to dry the substrate after the step of cleaning.

27. The method according to claim 20 wherein the inner sealing member is an o-ring and the outer sealing member is an inflatable membrane.

28. The method according to claim 27 wherein the step of providing includes the step of inflating the inflatable membrane and the step of removing includes the step of deflating the inflatable membrane.

29. The method according to claim 28 wherein the step of processing the frontside of the substrate performs chemical mechanical polishing of the frontside of the substrate using a pad, and wherein the frontside of the substrate and the pad are in contact with and move relative to each other.

30. The method according to claim 28 wherein the step of processing the frontside of the substrate performs electrochemical deposition of a conductor using an electrolyte as the processing solution.

31. The method according to claim 28 wherein the step of processing the frontside of the substrate performs electropolishing of the frontside of the substrate using a pad for polishing of the substrate.

32. The method according to claim 28 wherein the step of processing the frontside of the substrate performs chemical mechanical polishing of the frontside of the substrate using a pad, and wherein the frontside of the substrate and the pad are in contact with and move relative to each other.

33. The method according to claim 23 wherein:

the step of providing the another seal moves the another o-ring attached to a vertically moveable housing of the substrate holder to a seal position; and

the step of removing the another seal retracts the vertically moveable housing of the substrate holder and the another o-ring to result in an unsealed position.

34. The method according to claim 33 wherein the step of processing the frontside of the substrate performs chemical mechanical polishing of the frontside of the substrate using a pad, and wherein the frontside of the substrate and the pad are in contact with and move relative to each other.

35. The method according to claim 33 wherein the step of processing the frontside of the substrate performs electrochemical deposition of a conductor using an electrolyte as the processing solution.

36. The method according to claim 33 wherein the step of processing the frontside of the substrate performs electropolishing of the frontside of the substrate using a pad for polishing of the substrate.

37. The method according to claim 33 wherein the step of processing the frontside of the substrate performs chemical mechanical polishing of the frontside of the substrate using a pad, and wherein the frontside of the substrate and the pad are in contact with and move relative to each other.

38. The method according to claim 1 further comprising a cleaning step, prior to the step of removing the another seal, to clean the substrate using a cleaning solution.