Apparatus and method for conditioning and monitoring media used for chemical-mechanical planarization

• US 6,755,718 B2
• Filed: 02/13/2001
• Issued: 06/29/2004
• Est. Priority Date: 08/31/1999
• Status: Expired due to Term

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Moore, Scott E.
• Primary Examiner(s): RACHUBA, MAURINA T
• Application Number:
  US09/782,893
• Publication Number:
  US 20010006871A1
• Time in Patent Office: 1,232 Days
• Field of Search: 451/5, 451/9, 451/10, 451/41, 451/56, 451/285-290, 451/443, 451/444
• US Class Current: 451/5
• CPC Class Codes: B24B 49/006 taking regard of the speed
• CPC Class Codes: B24B 49/16 taking regard of the load
• CPC Class Codes: B24B 53/017 Devices or means for dressing, cleaning or otherwise conditioning lapping tools
• CPC Class Codes: B24B 53/12 Dressing tools; Holders therefor

Abstract

A method and apparatus for conditioning and monitoring a planarizing medium used for planarizing a microelectronic substrate. In one embodiment, the apparatus can include a conditioning body having a conditioning surface that engages a planarizing surface of the planarizing medium and is movable relative to the planarizing medium. A force sensor is coupled to the conditioning body to detect a frictional force imparted to the conditioning body by the planarizing medium when the conditioning body and the planarizing medium are moved relative to each other. The apparatus can further include a feedback device that controls the motion, position, or force between the conditioning body and the planarizing medium to control the conditioning of the planarizing medium.

Claims

1. An apparatus for monitoring conditioning of a planarizing medium used for planarizing a microelectronic substrate, comprising:

a conditioning body having a conditioning surface configured to engage a planarizing surface of the planarizing medium, at least one of the conditioning body and the planarizing medium being movable relative to the other of the conditioning body and the planarizing medium to condition the planarizing surface;

a support member coupled to the conditioning body;

a strain gauge sensor coupled to the support member to detect a deflection of the support member resulting from a frictional force in a plane of the planarizing surface, the frictional force being imparted to the conditioning body by the planarizing medium when the one of the conditioning body and the planarizing medium is moved relative to the other of the conditioning body and the planarizing medium.

2. The apparatus of claim 1 wherein the planarizing medium includes a polishing pad.

3. The apparatus of claim 1 wherein the conditioning body has a conditioning surface generally parallel to the planarizing surface.

4. The apparatus of claim 1 wherein the conditioning body includes abrasive elements for abrading the planarizing surface of the planarizing medium.

5. The apparatus of claim 1, further comprising:

a first support member having first and second ends and being rotatably coupled toward the first end to the conditioning body, the second end of the first support member extending away from the conditioning body; and

a second support member coupled at a pivotable coupling to the first support member toward the second end of the first support member, the sensor being positioned between the first and second support members, the first support member being pivotable relative to the second support member to transmit a force to the sensor corresponding to the frictional force.

6. The apparatus of claim 1, further comprising an actuator coupled to the conditioning body for controlling at least one of a position of the conditioning body and an approximately normal force between the conditioning body and the planarizing medium, the actuator being coupled to the sensor to receive signals from the sensor and adjust the one of the position and the approximately normal force in response to the signal.

7. An apparatus for measuring forces during conditioning of a chemical-mechanical planarizing surface, comprising:

a planarizing medium having a planarizing surface for removing material from a microelectronic substrate, the planarizing surface defining a planarizing surface plane;

a conditioning body adjacent to the planarizing medium, at least one of the conditioning body and the planarizing medium being movable relative to the other of the conditioning body and the planarizing medium for conditioning the planarizing surface, the conditioning body and the planarizing medium generating a force in the planarizing surface plane when the one of the conditioning body and the planarizing medium moves relative to the other of the conditioning body and the planarizing medium; and

a strain gauge sensor operatively coupled to the conditioning body to detect the force.

8. The apparatus of claim 7 wherein the planarizing medium includes a polishing pad.

9. The apparatus of claim 7 wherein the conditioning body has a conditioning surface generally parallel to the planarizing surface.

10. The apparatus of claim 7 wherein the conditioning body is rotatable relative to the planarizing medium.

11. The apparatus of claim 7 wherein the conditioning body is translatable relative to the planarizing medium.

12. The apparatus of claim 7 wherein the planarizing medium is rotatable relative to the conditioning body.

13. The apparatus of claim 7 wherein the force is a drag force, further comprising:

a first support member having first and second ends and being rotatably coupled toward the first end to the conditioning body, the second end of the first support member extending away from the conditioning body; and

a second support member coupled at a pivotable coupling to the first support member toward the second end of the first support member, the sensor being positioned between the first and second support members, the first support member being pivotable relative to the second support member to transmit a force to the sensor corresponding to the drag force.

14. The apparatus of claim 7, further comprising:

a piston; and

a cylinder having an open end and a closed end, the cylinder slidably receiving the piston, at least one of the piston and the cylinder being coupled to the conditioning body to slide relative to the other of the piston and the cylinder under the influence of the force on the conditioning body, the piston and the cylinder defining a gap between an end of the piston and the closed end of the cylinder, the force sensor including a gauge positioned to measure movement of the piston relative to the cylinder.

15. The apparatus of claim 7, further comprising a feedback device coupled to the sensor and the conditioning body for changing at least one of the force between the conditioning body and the polishing pad and a position of the conditioning body relative to the polishing pad in response to a signal from the sensor.

16. An apparatus for monitoring conditioning of a planarizing medium used for chemical-mechanical planarization of a microelectronic substrate, comprising:

a conditioning body having a conditioning surface configured to engage a planarizing surface of the planarizing medium, at least one of the conditioning body and the planarizing medium being movable relative to the other of the conditioning body and the planarizing medium to condition the planarizing surface, the conditioning body generating a drag force generally parallel to the planarizing surface;

a first support member having first and second ends and being rotatably coupled toward the first end to the conditioning body, the second end of the first support member extending away from the conditioning body;

a second support member coupled at a pivotable coupling to the first support member toward the second end of the first support member;

an actuator coupled to the conditioning body with a support assembly to control at least one of a generally normal force between the conditioning body and the planarizing medium and a position of the conditioning body relative to the planarizing medium;

a sensor coupled to the support assembly to detect the drag force, the sensor being positioned between the first and second support members, the first support member being pivotable relative to the second support member to transmit a force to the sensor corresponding to the drag force; and

a feedback device coupled to the actuator to control activation of the actuator in response to a signal received from the force sensor.

17. The apparatus of claim 16 wherein the feedback device includes a microprocessor.

18. The apparatus of claim 16 wherein the actuator is positioned to move the conditioning body laterally over the planarizing surface.

19. The apparatus of claim 16 wherein the actuator is positioned to rotate the conditioning body in a generally circular motion over the planarizing surface.

20. The apparatus of claim 16 wherein the planarizing medium includes a polishing pad.

21. The apparatus of claim 16 wherein the sensor includes a force sensor.

22. The apparatus of claim 16 wherein the sensor includes a strain gauge.

23. A method for monitoring a polishing pad used for planarizing a microelectronic substrate, the method comprising:

engaging a conditioning body with a planarizing surface of a first polishing pad;

applying a force to the first polishing pad via the conditioning body;

moving at least one of the first polishing pad and the conditioning body relative to the other of the first polishing pad and the conditioning body;

detecting a first frictional force of the polishing pad on the conditioning body in a plane of the planarizing surface;

applying a force to a second polishing pad via the conditioning body;

moving at least one of the second polishing pad and the conditioning body relative to the other of the second polishing pad and the conditioning body;

detecting a second frictional force of the second polishing pad on the conditioning body in a plane of the planarizing surface; and

comparing the first and second fictional forces.

24. The method of claim 23 wherein applying a force includes applying a force to the conditioning body different than a weight of the conditioning body.

25. The method of claim 23 wherein the force is a first force, further comprising conditioning the polishing pad by applying a second force to the conditioner greater than the first force to remove material from the planarizing surface of the polishing pad.

26. An apparatus for monitoring conditioning of a planarizing medium used for planarizing a microelectronic substrate, comprising:

a conditioning body having a conditioning surface configured to engage a planarizing surface of the planarizing medium, at least one of the conditioning body and the planarizing medium being movable relative to the other of the conditioning body and the planarizing medium to condition the planarizing surface; and

a strain gauge sensor coupled to the conditioning body to detect a frictional force in a plane of the planarizing surface, the frictional force being imparted to the conditioning body by the planarizing medium when the one of the conditioning body and the planarizing medium is moved relative to the other of the conditioning body and the planarizing medium.

27. The apparatus of claim 26 wherein the planarizing medium includes a polishing pad.

28. The apparatus of claim 26 wherein the conditioning body has a conditioning surface generally parallel to the planarizing surface.

29. The apparatus of claim 26 wherein the conditioning body includes abrasive elements for abrading the planarizing surface of the planarizing medium.

30. The apparatus of claim 26, further comprising a support member coupled to the conditioning body, further wherein the strain gauge is connected to the support member to detect a deflection of the support member resulting from the force on the conditioning body.

31. The apparatus of claim 26, further comprising:

a first support member having first and second ends and being rotatably coupled toward the first end to the conditioning body, the second end of the first support member extending away from the conditioning body; and

a second support member coupled at a pivotable coupling to the first support member toward the second end of the first support member, the sensor being positioned between the first and second support members, the first support member being pivotable relative to the second support member to transmit a force to the sensor corresponding to the frictional force.

32. The apparatus of claim 26, further comprising an actuator coupled to the conditioning body for controlling at least one of a position of the conditioning body and an approximately normal force between the conditioning body and the planarizing medium, the actuator being coupled to the sensor to receive signals from the sensor and adjust the one of the position and the approximately normal force in response to the signal.

33. An apparatus for measuring forces during conditioning of a chemical-mechanical planarizing surface, comprising:

a planarizing medium having a planarizing surface for removing material from a microelectronic substrate, the planarizing surface defining a planarizing surface plane;

a conditioning body adjacent to the planarizing medium, at least one of the conditioning body and the planarizing medium being movable relative to the other of the conditioning body and the planarizing medium for conditioning the planarizing surface, the conditioning body and the planarizing medium generating a force in the planarizing surface plane when the one of the conditioning body and the planarizing medium moves relative to the other of the conditioning body and the planarizing medium;

a force sensor operatively coupled to the conditioning body to detect the force;

a piston; and

a cylinder having an open end and a closed end, the cylinder slidably receiving the piston, at least one of the piston and the cylinder being coupled to the conditioning body to slide relative to the other of the piston and the cylinder under the influence of the force on the conditioning body, the piston and the cylinder defining a gap between an end of the piston and the closed end of the cylinder, the force sensor including a gauge positioned to measure movement of the piston relative to the cylinder.

34. The apparatus of claim 33 wherein the planarizing medium includes a polishing pad.

35. The apparatus of claim 33 wherein the conditioning body has a conditioning surface generally parallel to the planarizing surface.

36. The apparatus of claim 33 wherein the conditioning body is rotatable relative to the planarizing medium.

37. The apparatus of claim 33 wherein the conditioning body is translatable relative to the planarizing medium.

38. The apparatus of claim 33 wherein the planarizing medium is rotatable relative to the conditioning body.

39. The apparatus of claim 33 wherein the force is a drag force, further comprising:

a first support member having first and second ends and being rotatably coupled toward the first end to the conditioning body, the second end of the first support member extending away from the conditioning body; and

a second support member coupled at a pivotable coupling to the first support member toward the second end of the first support member, the sensor being positioned between the first and second support members, the first support member being pivotable relative to the second support member to transmit a force to the sensor corresponding to the drag force.

40. The apparatus of claim 33, further comprising a feedback device coupled to the sensor and the conditioning body for changing at least one of the force between the conditioning body and the polishing pad and a position of the conditioning body relative to the polishing pad in response to a signal from the sensor.

41. An apparatus for monitoring conditioning of a planarizing medium used for chemical-mechanical planarization of a microelectronic substrate, comprising:

a conditioning body having a conditioning surface configured to engage a planarizing surface of the planarizing medium, at least one of the conditioning body and the planarizing medium being movable relative to the other of the conditioning body and the planarizing medium to condition the planarizing surface, the conditioning body generating a drag force generally parallel to the planarizing surface;

an actuator coupled to the conditioning body with a support assembly to control at least one of a generally normal force between the conditioning body and the planarizing medium and a position of the conditioning body relative to the planarizing medium;

a strain gauge sensor coupled to the support assembly to detect the drag force; and

a feedback device coupled to the actuator to control activation of the actuator in response to a signal received from the force sensor.

42. The apparatus of claim 41 wherein the feedback device includes a microprocessor.

43. The apparatus of claim 41 wherein the actuator is positioned to move the conditioning body laterally over the planarizing surface.

44. The apparatus of claim 41 wherein the actuator is positioned to rotate the conditioning body in a generally circular motion over the planarizing surface.

45. The apparatus of claim 41 wherein the planarizing medium includes a polishing pad.

46. The apparatus of claim 41 further comprising:

a first support member having first and second ends and being rotatably coupled toward the first end to the conditioning body, the second end of the first support member extending away from the conditioning body; and

a second support member coupled at a pivotable coupling to the first support member toward the second end of the first support member, the sensor being positioned between the first and second support members, the first support member being pivotable relative to the second support member to transmit a force to the sensor corresponding to the drag force.