Method and apparatus of sealing wafer backside for full-face electrochemical plating

• US 6,939,206 B2
• Filed: 05/31/2002
• Issued: 09/06/2005
• Est. Priority Date: 03/12/2001
• Status: Expired due to Term

• Current Assignee: Novellus Systems Incorporated (Lam Research Corporation)
• Original Assignee: ASM NuTool, Inc. (ASM International NV)
• Inventors: Basol, Bulent M., Ashjaee, Jalal, Talieh, Homayoun, Volodarsky, Konstantin
• Primary Examiner(s): NGUYEN, GEORGE BINH MINH
• Application Number:
  US10/159,295
• Publication Number:
  US 20030008602A1
• Time in Patent Office: 1,194 Days
• Field of Search: 451285-290, 451/56, 451/67, 451/388, 451/398, 451/41, 451/5, 451/57, 451/54, 220/4.22, 277/647, 118/52, 134/1, 204/224.M, 204/277, 205/662
• US Class Current: 451/41
• 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 17/004 Sealing devices
• CPC Class Codes: C25D 17/06 Suspending or supporting devices for articles to be coated
• CPC Class Codes: C25D 7/123 Semiconductors first coated with a seed layer or a conductive layer
• CPC Class Codes: H01L 21/6704 for wet cleaning or washing
• CPC Class Codes: H01L 21/67126 Apparatus for sealing, encapsulating, glassing, decapsulating or the like processes H01L23/02, H01L23/28
• 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 a plurality of concentric sealing members that provide a seal, with the outer seal independently movable to allow cleaning of a peripheral backside of the wafer to occur while the wafer is still attached to the wafer carrier, and a plurality of vacuum openings that a re disposed only adjacent to an inner side of the inner seal at a location corresponding to the backside periphery of the wafer.

Claims

1. A substrate carrier that is capable of receiving a vacuum and holding a substrate from a backside for processing a frontside of the substrate, using a solution, the substrate carrier comprising:

a base of the substrate carrier for placing the substrate thereon;

a sealing member disposed on the base and defining an inner region of the base, the sealing member adapted to contact the backside of the substrate to thereby establish a backside inner region of the substrate, and assist in preventing the solution from reaching the backside inner region of the substrate during the processing of the substrate; and

multiple sealing members disposed outside the sealing member and adapted to assist in preventing the solution from reaching the backside inner region of the substrate during the processing of the substrate, wherein the multiple sealing members include at least two outer sealing members, the at least two outer sealing members disposed outside of and around the scaling member and adapted to contact the backside of the substrate and thereby assist in preventing the solution from reaching the backside inner region of the substrate, wherein one or more of the at least two outer sealing members is an inflatable sealing member.

2. The substrate carrier according to claim 1 wherein the one or more inflatable sealing member is inflated during the processing of the substrate, and is not inflated during a subsequent processing of the substrate.

3. The substrate carrier according to claim 1 wherein the one or more inflatable sealing member is inflated by a gas that is provided through at least one hole that is formed in the base.

4. A method of processing a frontside of a substrate using a processing solution and cleaning a peripheral backside of a substrate using a cleaning solution, the method comprising the steps of:

attaching the substrate to a substrate holder, the substrate holder including an inner sealing member, a middle sealing member, and an outer sealing member, such that the inner sealing member continuously applies a seal during processing and cleaning and the middle and outer sealing members are moveable relative to the inner sealing member and wherein the middle and outer sealing members can intermittently apply a seal;

applying the seal using the middle and outer sealing members;

processing the frontside of the substrate using the processing solution when the seal is applied by the middle and outer sealing members, thereby substantially preventing the processing solution from reaching the inner sealing member;

upon completion of processing the frontside of the substrate, removing the seal applied by the outer sealing member;

cleaning the peripheral backside of the substrate using the cleaning solution when the seal applied by the outer sealing member remains removed and the seal applied by the middle and the inner sealing members is retained;

upon completion of cleaning the frontside of the substrate, removing the seal applied by the middle sealing member; and

spin-drying the substrate when the seal applied by the outer and middle sealing members remains removed and the seal applied by the inner sealing member is retained.

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

6. The method according to claim 5 wherein:

the step of applying the seal by the outer and middle sealing members uses a gas that is emitted from the substrate holder to a peripheral backside of the substrate; and

the steps of removing the seals applied by each sealing member stop the emission of the gas from the substrate holder.

7. The method according to claim 5 wherein:

the step of applying the seal by the outer and middle sealing members comprises inflating an inflatable membrane for each sealing member; and

the steps of removing the seals comprises deflating the respective inflatable membranes.

8. The method according to claim 5 wherein:

the step of applying the seal by the outer and middle sealing members moves an outer moveable housing carrying the outer sealing member into an outer seal position and moves a middle moveable housing carrying the middle sealing member into a middle seal position; and

the steps of removing the seals comprises retracting the outer and middle moveable housings and the respective sealing members into unsealed positions.

9. The method according to claim 4 wherein the step of processing the frontside of the substrate performs one of electrochemical etching and electrochemical mechanical etching of a conductor using one of an electroetching solution and an electrolyte as the processing solution.

10. The method according to claim 9 wherein the step of processing the frontside of the substrate performs chemical mechanical polishing of a conductor using one of a polishing solution and a slurry.

11. The method according to claim 10 wherein:

the step of applying the seal by the outer and middle sealing members uses a gas that is emitted from the substrate holder to a peripheral backside of the substrate; and

the steps of removing the seals applied by each sealing member stop the emission of the gas from the substrate holder.

12. The method according to claim 10 wherein:

the step of applying the seal by the outer and middle sealing members comprises inflating an inflatable membrane for each sealing member; and

the steps of removing the seals comprises deflating the respective inflatable membranes.

13. The method according to claim 10 wherein:

the step of applying the seal by the outer and middle sealing members moves an outer-moveable housing carrying the outer sealing member into an outer seal position and moves a middle moveable housing carrying the middle sealing member to a middle seal position; and

the steps of removing the seals retracts the outer and middle moveable housings and the respective sealing members into respective unsealed positions.

14. The method according to claim 4 wherein:

the step of applying the seal by the outer and middle sealing members uses a gas that is emitted from the substrate holder to a peripheral backside of the substrate; and

the steps of removing the seals applied by each sealing member stop the emission of the gas from the substrate holder.

15. The method according to claim 4 wherein:

the step of applying the seal the outer and middle sealing members comprises inflating an inflatable membrane for each member; and

the steps of removing the seals comprises deflating the respective inflatable membranes.

16. The method according to claim 4 wherein:

the step of applying the seal the outer and middle sealing members an outer moveable housing carrying the outer sealing member into an outer seal position and moves a middle moveable housing carrying the middle sealing member to a middle seal position; and

the steps of removing the seals retracts the outer and middle moveable and the respective sealing members into respective unsealed positions.

17. The method according to claim 4 wherein the step of attaching attaches the substrate to the substrate holder using a vacuum.

18. The method according to claim 17 wherein the vacuum prevents the substrate from lateral displacement relative to the substrate holder during the steps of processing and cleaning.

19. The method according to claim 18 wherein the vacuum thereby does not require the usage of a retaining ring and flow of the processing solution is not obstructed during the step of processing.

20. The method according to claim 18 wherein the step of processing performs full face processing of the frontside of the substrate.

21. The method according to claim 20 wherein the vacuum thereby does not require the usage of a retaining ring and flow of the processing solution is not obstructed during the step of processing.

22. The method according to claim 4, wherein, after the step of spin-drying, further including the step of removing the wafer from substrate holder, the step of removing including applying pressure from at least one of the inner, middle and outer sealing members onto the backside of the substrate.

23. A method of holding a substrate on a substrate holder for processing a frontside of the substrate using a processing solution, comprising the steps of:

attaching the substrate to the substrate holder, the substrate holder including multiple sealing members, an inner sealing member of the multiple sealing members contacting the substrate and applying a permanent seal to a backside region of the substrate with vacuum causing the substrate holder to hold the backside region of the substrate; and

processing the frontside of the substrate using the processing solution while the permanent seal exists, thereby substantially preventing the processing solution from reaching the backside region, 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 wafer and the pad are in contact with and move relative to each other.

24. The method according to claim 23 wherein the processing solution is a slurry.

25. A method of holding a substrate on a substrate holder for processing a frontside of the substrate using a processing solution, comprising the steps of:

attaching the substrate to the substrate holder, the substrate holder including multiple sealing members, an inner sealing member of the multiple sealing members contacting the substrate and applying a permanent seal to a backside region of the substrate with vacuum causing the substrate holder to hold the backside region of the substrate; and

processing the frontside of the substrate using the processing solution while the permanent seal exists, thereby substantially preventing the processing solution from reaching the backside region, wherein the permanent seal provided by the inner sealing member and 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, wherein the permanent seal provided by the inner sealing member and the vacuum solely prevents lateral movement of the substrate during processing relative to the substrate holder, and 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 wafer and the pad are in contact with and move relative to each other.

26. The method according to claim 25 wherein the processing solution is a slurry.

27. A method of holding a substrate on a substrate holder for processing a frontside of the substrate using a processing solution, comprising the steps of:

attaching the substrate to the substrate holder, the substrate holder including multiple sealing members, an inner sealing member of the multiple sealing members contacting the substrate and applying a permanent seal to a backside region of the substrate with vacuum causing the substrate holder to hold the backside region of the substrate; and

processing the frontside of the substrate using the processing solution while the permanent seal exists, thereby substantially preventing the processing solution from reaching the backside region, wherein the permanent seal provided by the inner sealing member and 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, wherein the permanent seal provided by the inner sealing member and the vacuum solely prevents lateral movement of the substrate during processing relative to the substrate holder, and wherein the step of processing uses a pad for polishing of the substrate and performs one of electrochemical deposition and electrochemical mechanical deposition of a conductor using an electrolyte as the processing solution.

28. A method of holding a substrate on a substrate holder for processing a frontside of the substrate using a processing solution, comprising the steps of:

attaching the substrate to the substrate holder, the substrate holder including multiple sealing members, an inner sealing member of the multiple sealing members contacting the substrate and applying a permanent seal to a backside region of the substrate with vacuum causing the substrate holder to hold the backside region of the substrate; and

processing the frontside of the substrate using the processing solution while the permanent seal exists, thereby substantially preventing the processing solution from reaching the backside region, wherein the permanent seal provided by the inner sealing member and 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, wherein the permanent seal provided by the inner sealing member and the vacuum solely prevents lateral movement of the substrate during processing relative to the substrate holder, and wherein the step of processing the frontside of the substrate performs one of electrochemical polishing and electrochemical mechanical polishing of the frontside of the substrate using a pad for polishing of the substrate.

29. An apparatus for holding a substrate from a backside using a vacuum during processing of a frontside of the substrate with a solution and a pad that contacts and moves relative to the frontside of the substrate, comprising:

a base for placing the substrate thereon; and

means for simultaneously holding the substrate on the base during the processing of the frontside of the substrate using the vacuum and preventing lateral movement of the substrate relative to the base during the processing using the vacuum, the means for holding including;

an inner sealing member disposed on the base and defining the inner region of the base and adapted to contact the backside of the substrate to thereby establish the backside inner region of the substrate; and

a sealing mechanism carrying at least two sealing members disposed outside the inner sealing member and adapted to assist in preventing the solution from reaching the backside inner region of the substrate during the processing of the substrate, wherein the sealing mechanism includes a middle sealing member and an outer sealing member disposed outside of and around the inner sealing member and adapted to contact the peripheral backside of the substrate and thereby assist in preventing the solution from reaching the backside inner region of the substrate, wherein at least one of the middle and outer sealing members is an inflatable sealing member.

30. The apparatus according to claim 29 wherein one or more of the at least one inflatable sealing member is inflated during the processing of the substrate, and is not inflated during a subsequent processing of the substrate.

31. An apparatus for holding a substrate from a backside using a vacuum during processing of a frontside of the substrate with a solution and a pad that contacts and moves relative to the frontside of the substrate, comprising:

a base for placing the substrate thereon; and

means for simultaneously holding the substrate on the base during the processing of the frontside of the substrate using the vacuum and preventing lateral movement of the substrate relative to the base during the processing using the vacuum, the means for holding including;

an inner sealing member disposed on the base and defining the inner region of the base and adapted to contact the backside of the substrate to thereby establish the backside inner region of the substrate; and

a sealing mechanism carrying at least two sealing members disposed outside the inner sealing member and adapted to assist in preventing the solution from reaching the backside inner region of the substrate during the processing of the substrate, wherein the sealing mechanism includes a middle sealing member and an outer sealing member disposed outside of and around the inner sealing member and adapted to contact the peripheral backside of the substrate and thereby assist in preventing the solution from reaching the backside inner region of the substrate, wherein at least one of the middle and outer sealing members is an o-ring.

32. The apparatus according to claim 31 wherein the inner sealing member is a hollow o-ring.

33. The apparatus according to claim 32 wherein the sealing inner, middle and outer sealing members are made from an elastomer material.

34. The apparatus according to claim 33 wherein the middle and outer sealing members are hollow o-rings.

35. The apparatus according to claim 32 wherein the hollow o-ring has a durometer rating of less than 50.

36. A method of processing a frontside of a plurality of substrates using a processing solution while holding each of the substrates to a substrate holder using a vacuum comprising the steps of:

attaching at least one of the substrates to the substrate holder using the vacuum, the substrate holder including a support pad and a plurality of sealing members, and inner sealing member of the plurality of sealing members having a surface that contacts the substrate such that the inner sealing member provides a permanent seal of a backside region of the substrate with the vacuum causing the substrate holder to hold the backside region of the substrate and the support pad including a first configuration of openings through which the vacuum connects to the substrate;

processing the frontside of the one substrate using the processing solution while sealing the backside region with the plurality of sealing members, thereby substantially preventing the processing solution from reaching the backside region of the substrate;

changing the support pad on the substrate holder with another support pad having a second configuration of opening different from the first configuration of openings;

attaching at least another of the substrates to the substrate holder using the vacuum, the substrate holder including the another support pad and the plurality of sealing members with the inner sealing member having the surface that contacts the another substrate such that the inner scaling member provides another permanent seal of the backside region of the another substrate with the vacuum causing the substrate holder to hold the backside region of the another substrate; and

processing the frontside of the another substrate using the processing solution while the another permanent seal exists, thereby substantially preventing the processing solution from reaching the backside region of the another substrate.

37. A substrate carrier that is capable of receiving a vacuum and holding a substrate from a backside for processing a frontside of the substrate using a solution, the substrate carrier comprising:

a base for placing the substrate thereon;

a first sealing member disposed on the base and defining an inner region of the base, and adapted to contact the backside of the substrate to thereby establish a backside inner region of the substrate, and assist in preventing the solution from reaching the backside inner region of the substrate during the processing of the substrate;

a sealing mechanism disposed outside of the sealing member and adapted to assist in preventing the solution from reaching the backside inner region of the substrate during the processing of the substrate, the sealing mechanism including a second and third sealing members disposed in a moveable housings that are adapted to position the second and third sealing members in respective seal positions and respective unsealed positions, the second and third sealing members disposed outside of and around the first sealing member and adapted to contact the backside of the substrate and thereby assist in preventing the solution from reaching the backside inner region of the substrate; and

an expandable membrane disposed between the first, second and third sealing members.

38. The apparatus according to claim 37 wherein the first, second and third sealing members and the expandable membrane are formed as an integral piece.

39. The substrate carrier according to claim 37, wherein a vacuum inlet disposed within the inner region of the base and connectable to the vacuum to allow the backside of the substrate to be held on the base.

40. A substrate carrier that is capable of receiving a vacuum and holding a substrate from a backside for processing a frontside of the substrate, using a solution, the substrate carrier comprising:

a base of the substrate carrier for placing the substrate thereon;

a sealing member disposed on the base and defining an inner region of the base, the sealing member adapted to contact the backside of the substrate to thereby establish a backside inner region of the substrate, and assist in preventing the solution from reaching the backside inner region of the substrate during the processing of the substrate; and

multiple sealing members disposed outside the sealing member and adapted to assist in preventing the solution from reaching the backside inner region of the substrate during the processing of the substrate, wherein the multiple sealing members are disposed in moveable housings that are adapted to position the multiple sealing members into a seal position and an unsealed position.

41. The substrate carrier according to claim 40 wherein the moveable housings are adapted to move together, thereby positioning the multiple sealing members into the seal position and the unsealed position together.

42. The substrate carrier according to claim 40 wherein the moveable housings are adapted to move independently, thereby positioning the multiple sealing members into the seal position and the unsealed position independent of one another.

43. A method of holding a substrate on a substrate holder for processing a frontside of the substrate using a processing solution, comprising the steps of:

attaching the substrate to the substrate holder, the substrate holder including multiple sealing members, an inner sealing member of the multiple sealing members contacting the substrate and applying a permanent seal to a backside region of the substrate with vacuum causing the substrate holder to hold the backside region of the substrate;

applying a seal to a peripheral backside of the substrate by a middle sealing member and an outer sealing member of the multiple sealing members, wherein the step of applying the seal by the middle and outer sealing members comprises moving the middle and outer sealing members to place them onto the peripheral backside of the substrate; and

after applying the seal, processing the frontside of the substrate using the processing solution while the permanent seal exists, thereby substantially preventing the processing solution from reaching the backside region.

44. The method according to claim 43, wherein the step of moving comprises moving the middle and outer sealing members together.

45. The method according to claim 43, wherein the step of moving comprises moving the middle and outer sealing members independent of one another.

46. The method according to claim 43, further comprising removing the middle and outer sealing members from the peripheral backside of the substrate to expose the peripheral backside to a cleaning solution during a cleaning step.

47. The method according to claim 43, further comprising the step of removing the outer sealing member from the peripheral backside of the substrate to expose the peripheral backside to a cleaning solution during a cleaning step.

48. The method according to claim 47, further comprising the step of removing the middle sealing member from the peripheral backside of the substrate to allow drying of the peripheral backside during a spin-drying step.