Polishing pad refurbisher for in situ, real-time conditioning and cleaning of a polishing pad used in chemical-mechanical polishing of microelectronic substrates

Abstract

A pad refurbisher that provides in situ, real-time conditioning and/or cleaning of a polishing surface on a polishing pad used in chemical-mechanical polishing of a semiconductor wafer and other microelectronic substrates. The pad refurbisher has a body adapted for attachment to a wafer carrier of a chemical-mechanical polishing machine, and a refurbishing element connected to the body. The body has a distal face positioned proximate to a perimeter portion of the wafer carrier and facing generally toward the polishing surface of the polishing pad. The body travels with the wafer carrier as the wafer carrier moves over the polishing pad. The refurbishing element is connected to the distal face of the body so that the refurbishing element can operatively engage the polishing surface substantially adjacent to the perimeter of the wafer carrier. The refurbishing element is a pad conditioning device and/or a pad cleaning device that conditions and/or cleans the polishing surface of the pad to remove waste particles from the polishing surface of the polishing pad and place the pad in a desired polishing condition. In operation, the refurbishing element travels with the wafer carrier and is selectively engaged with the polishing surface while the wafer carrier presses the wafer against the polishing surface to selectively condition and/or clean generally only the deteriorated areas on the pad.

1. A pad refurbisher for in situ, real-time refurbishing of a polishing surface on a polishing pad used in chemical-mechanical polishing of a semiconductor wafer, comprising:
 a body adapted for attachment to a wafer carrier of a chemical-mechanical polishing machine with the body having a first ring and a second ring each with a face positioned proximate to a perimeter portion of the wafer carrier and facing the polishing surface of the polishing pad, the body being adapted to travel with the wafer carrier as the wafer carrier moves over the polishing pad wherein the body is movably attached to the wafer carrier; and  
 a refurbishing element connected to the face of the bodya first refurbishment element connected to the face of the first ring and a second refurbishment element connected to the face of the second ring, the first ring operably coupled to a first linear actuator configured to independently move the first ring downwardly to selectively engage the first refurbishment element with the polishing surface and upwardly with respect to the wafer carrier and the second ring to selectively disengage the first refurbishment element from the polishing surface and the second ring operably coupled to a second linear actuator configured to independently move the second ring downwardly to selectively engage the second refurbishment element with the polishing surface and upwardly with respect to the wafer carrier and the first ring to selectively disengage the second refurbishment element from the polishing surface, the first ring being positioned radially outward from the perimeter of the wafer carrier and the second ring being positioned radially outward from the first ring, the first and the second refurbishing elementelements being adapted to engage the polishing surface substantially adjacent to the perimeter portion of the wafer carrier and traveling with the wafer carrier while the wafer carrier moves the wafer over the polishing surface.  
 
     
     
       2. The pad refurbisher of  claim 1  wherein the body is fixed to the wafer carrier. 
     
     
       3. The pad refurbisher of  claim 1  wherein the body is slidably attached to the wafer carrier. 
     
     
       4. The pad refurbisher of  claim 3 , further comprising a linear actuator attached to the body, wherein the actuator independently moves the body with respect to the wafer carrier along an axis substantially normal to the polishing surface to selectively engage the refurbishing element with areas on the polishing surface in need of cleansing and to selectively disengage the refurbishing element from areas on the pad in adequate condition. 
     
     
       5. The pad refurbisher of  claim 1  wherein the face is a distal face of the body defining a ring positioned radially outwardly from the perimeter of the wafer carrier. 
     
     
       6. The pad refurbisher of  claim 1  wherein the body has  the first ring and the second ring each include a plurality of arcuate segments positioned radially outwardly from the perimeter of the wafer carrier, the arcuate segments being spaced apart from one another around the wafer carrier and each arcuate segment having a distal face facing generally towards the polishing surface of the polishing pad. 
     
     
       7. The pad refurbisher of  claim 1  wherein one of the refurbishing element  elements is a brush comprising a plurality of bristles extending downwardly from the face towards the polishing surface, the bristles engaging the polishing surface to clean waste particles from the pad. 
     
     
       8. The pad refurbisher of  claim 1  wherein one of the refurbishing element  elements is a pad conditioner that removes a layer of pad material from polishing surface of the pad to form a new polishing surface on the polishing pad. 
     
     
       9. The pad refurbisher of  claim 8  wherein the pad conditioner comprises a pad with a plurality of embedded diamonds, the pad being connected to the distal surface of the body. 
     
     
       10. The pad refurbisher of  claim 1  wherein the body has a first ring with a first refurbishing element and a second ring with a second refurbishing element, the first ring being positioned radially outwardly from the perimeter of the wafer carrier and the second ring being positioned radially outwardly from the first ring. 
     
     
       11. The pad refurbisher of  claim 10  wherein the first refurbishing element is a pad cleaner and the second refurbishing element is a pad conditioner. 
     
     
       12. The pad refurbisher of  claim 1  wherein the body is adapted to be symmetrically positioned about the center of the wafer carrier. 
     
     
       13. A polishing machine for chemical-mechanical polishing of a semiconductor wafer, comprising:
 a platen having an upper surface;  
 a polishing pad positioned on the upper surface of the platen, the polishing pad having a polishing surface facing away from the platen,  
 a wafer carrier for carrying the wafer, the wafer carrier being positioned over the polishing pad and moveable along an axis substantially normal to the upper surface of the platen to engage the wafer with the polishing pad, wherein at least one of the platen and the wafer carrier moves with respect to the other to impart relative motion between the wafer and the polishing pad; and  
 a pad refurbisher having a body including a first ring and a second ring each with a face positioned proximate to a perimeter portion of the wafer carrier and facing generally towards the polishing surface and a refurbishing element connected to the face , the first ring having a first refurbishment element connected to the face thereof, the first ring operably coupled to a first linear actuator configured to independently move the first ring downwardly to selectively engage the first refurbishment element with the polishing surface and upwardly with respect to the wafer carrier and the second ring to selectively disengage the first refurbishment element from the polishing surface and the second ring having a second refurbishment element connected to the face thereof, the second ring operably coupled to a second linear actuator configured to independently move the second ring downwardly to selectively engage the second refurbishment element with the polishing surface and upwardly with respect to the wafer carrier and the first ring to selectively disengage the second refurbishment element from the polishing surface, the first ring being positioned radially outward from the perimeter of the wafer carrier and the second ring being positioned radially outward from the first ring, the body being attached to the wafer carrier so that the body and the first and the second refurbishing element  elements travel with the wafer carrier as the wafer carrier moves with respect to the polishing pad, wherein the first refurbishing element engages the polishing surface substantially adjacent to the perimeter portion of the wafer carrier while the wafer carrier moves the wafer over the polishing surface and wherein the body is movably attached to the wafer carrier.  
 
     
     
       14. The polishing machine of  claim 13  wherein the body is fixed to the wafer carrier. 
     
     
       15. The polishing machine of  claim 13  wherein the body is slidably attached to the wafer carrier. 
     
     
       16. The polishing machine of  claim 15 , further comprising a linear actuator attached to the body, wherein the actuator independently moves the body downwardly and upwardly with respect to the wafer carrier along an axis substantially perpendicular to the polishing surface to selectively engage the refurbishing element with areas on the polishing surface in need of cleansing and to selectively disengage the refurbishing element from areas on the pad in adequate condition. 
     
     
       17. The polishing machine of  claim 13  wherein the face of the body is a ring positioned radially outwardly from the perimeter of the wafer carrier. 
     
     
       18. The polishing machine of  claim 13  wherein the body has  the first ring and the second ring each include a plurality of arcuate segments positioned radially outwardly from the perimeter of the wafer carrier, the arcuate segments being spaced apart from one another around the wafer carrier and each arcuate segment having a distal face facing generally towards the polishing surface of the polishing pad. 
     
     
       19. The polishing machine of  claim 13  wherein one of the refurbishing element  elements is a brush comprising a plurality of bristles extending downwardly from the face towards the polishing surface, the bristles engaging the polishing surface to clean waste particles from the pad. 
     
     
       20. The polishing machine of  claim 13  wherein one of the refurbishing element  elements is a pad conditioner that removes a layer of pad material from polishing surface of the pad to form a new polishing surface on the polishing pad. 
     
     
       21. The polishing machine of  claim 20  wherein the pad conditioner comprises a pad with a plurality of embedded diamonds, the pad being connected to the distal surface of the body. 
     
     
       22. The polishing machine of  claim 13  wherein the body has a first ring with a first refurbishing element and a second ring with a second refurbishing element, the first ring being positioned radially outwardly from the perimeter of the wafer carrier and the second ring being positioned radially outwardly from the first ring. 
     
     
       23. The polishing machine of  claim 13  wherein the first refurbishing element is a pad cleaner and the second refurbishing element is a pad conditioner. 
     
     
       24. The polishing machine of  claim 13  wherein the pad refurbishing element is symmetrically positioned about the center of the wafer carrier. 
     
     
       25. A method for refurbishing a polishing pad, comprising the steps of:
 providing a pad refurbisher having a body including a first ring and a second ring each with a face positioned proximate to a perimeter portion of a wafer carrier of a chemical-mechanical polishing machine and facing generally towards the polishing surface, and a first refurbishing element connected to the face of the body  first ring and a second refurbishment element connected to the face of the second ring, the body being movably attached to the wafer carrier;  
 selectively engaging the padone of the first and the second refurbishing elementelements with the polishing pad; and  
 moving at least one of the wafer carrier and the polishing pad with respect to the other to pass at least one of the refurbishing element  elements across the polishing pad.  
 
     
     
       26. The method of  claim 25  wherein the selectively engaging step comprises selectively lowering the body towards the polishing pad while the wafer carrier presses a wafer against the polishing pad and moves the wafer over the polishing pad to polish the wafer. 
     
     
       27. The method of  claim 26  wherein the method further comprises selectively disengaging one of the refurbishing element  elements from the polishing pad. 
     
     
       28. The method of  claim 25  wherein the engaging step comprises lowering the wafer carrier until one of the refurbishing element  elements and a wafer abut the polishing pad. 
     
     
       29. The method of  claim 25  wherein the first refurbishing element comprises a pad conditioner and the second refurbishment element comprises a pad cleaner, and wherein the engaging step comprises pressing the pad conditioner and the pad cleaner against the polishing pad. 
     
     
       30. The method of  claim 26  wherein one of the refurbishing element  elements is selectively engaged with deteriorated portions of the polishing pad with accumulations of waste matter. 
     
     
       31. A pad refurbisher for refurbishing a polishing surface on a polishing pad used in chemical- mechanical polishing of a semiconductor wafer, comprising:      a body adapted for attachment to a wafer carrier of a chemical - mechanical polishing machine with the body having a first ring and a second ring each with a face positioned proximate to a perimeter portion of the wafer carrier and facing the polishing surface of the polishing pad; and        a first refurbishment element connected to the face of the first ring and a second refurbishment element connected to the face of the second ring, the first ring operably coupled to a first linear actuator configured to independently move the first ring downwardly to selectively engage the first refurbishment element with the polishing surface and upwardly with respect to the wafer carrier and the second ring to selectively disengage the first refurbishment element from the polishing surface and the second ring operably coupled to a second linear actuator configured to independently move the second ring downwardly to selectively engage the second refurbishment element with the polishing surface and upwardly with respect to the wafer carrier and the first ring to selectively disengage the second refurbishment element from the polishing surface, the first ring being positioned radially outward from the perimeter of the wafer carrier and the second ring being positioned radially outward from the first ring, the first and the second refurbishing elements being adapted to engage the polishing surface substantially adjacent to the perimeter portion of the wafer carrier.     
     
     
       32. The pad refurbisher of  claim 31  wherein the body is fixed to the wafer carrier. 
     
     
       33. The pad refurbisher of  claim 31  wherein the body is slidably attached to the wafer carrier. 
     
     
       34. The pad refurbisher of  claim 31  wherein the face is a distal face of the body defining a ring positioned radially outwardly from the perimeter of the wafer carrier. 
     
     
       35. The pad refurbisher of  claim 31  wherein the first ring and the second ring include a plurality of arcuate segments positioned radially outwardly from the perimeter of the wafer carrier, the arcuate segments being spaced apart from one another around the wafer carrier and each arcuate segment having a distal face facing generally towards the polishing surface of the polishing pad. 
     
     
       36. The pad refurbisher of  claim 31  wherein one of the refurbishing elements is a brush comprising a plurality of bristles extending downwardly from the face towards the polishing surface, the bristles engaging the polishing surface to clean waste particles from the pad. 
     
     
       37. The pad refurbisher of  claim 31  wherein one of the refurbishing elements is a pad conditioner that removes a layer of pad material from polishing surface of the pad to form a new polishing surface on the polishing pad. 
     
     
       38. The pad refurbisher of  claim 37  wherein the pad conditioner comprises a pad with a plurality of embedded diamonds, the pad being connected to the distal surface of the body. 
     
     
       39. The pad refurbisher of  claim 31  wherein the first refurbishing element is a pad cleaner and the second refurbishing element is a pad conditioner. 
     
     
       40. The pad refurbisher of  claim 31  wherein the body is adapted to be symmetrically positioned about the center of the wafer carrier. 
     
     
       41. A polishing machine for chemical- mechanical polishing of a semiconductor wafer, comprising:      a platen having an upper surface;        a polishing pad positioned on the upper surface of the platen, the polishing pad having a polishing surface facing away from the platen,        a wafer carrier for carrying the wafer; and        a pad refurbisher having a body attached to the wafer carrier, the body including a first ring having a first refurbishment element and a second ring having a second refurbishment element, the first operably coupled to a first linear actuator configured to independently move the first ring downwardly to selectively engage the first refurbishment element with the polishing surface and upwardly with respect to the wafer carrier and the second ring to selectively disengage the first refurbishment element from the polishing surface and the second ring operably coupled to a second linear actuator configured to independently move the second ring downwardly to selectively engage the second refurbishment element with the polishing surface and upwardly with respect to the wafer carrier and the first ring to selectively disengage the second refurbishment element from the polishing surface, the first ring being positioned radially outward from the perimeter of the wafer carrier and the second ring being positioned radially outward from the first ring.     
     
     
       42. The polishing machine of  claim 41  wherein the first and the second ring each comprise a face positioned proximate to a perimeter portion of the wafer carrier and facing generally towards the polishing surface. 
     
     
       43. The polishing machine of  claim 42  wherein the first refurbishing element is connected to the face of the first ring and the second refurbishment element is connected to the face of the second ring, and wherein the body being attached to the wafer carrier so that the body and each of the refurbishing elements travel with the wafer carrier as the wafer carrier moves with respect to the polishing pad, and wherein each of the refurbishing elements engages the polishing surface substantially adjacent to the perimeter portion of the wafer carrier while the wafer carrier moves the wafer over the polishing surface. 
     
     
       44. The polishing machine of  claim 41  wherein the body is fixed to the wafer carrier. 
     
     
       45. A method for refurbishing a polishing pad, comprising the steps of:
   providing a pad refurbisher attached to a wafer carrier, the pad refurbisher having a first ring bearing a first refurbishment element and a second ring bearing a second refurbishment element,        selectively engaging one of the first and the second refurbishing elements with the polishing pad; and        moving at least one of the wafer carrier and the polishing pad with respect to the other to pass at least one of the refurbishing elements across the polishing pad.     
     
     
       46. The method of  claim 45  wherein selectively engaging comprises selectively lowering at least one of the refurbishing elements towards the polishing pad while the wafer carrier presses a wafer against the polishing pad and moves the wafer over the polishing pad to polish the wafer. 
     
     
       47. The method of  claim 45  further comprising selectively disengaging the one of refurbishing elements from the polishing pad. 
     
     
       48. The method of  claim 47  wherein one of the refurbishing elements is selectively disengaged from relatively unused portions of the polishing pad not having accumulations of waste matter. 
     
     
       49. The method of  claim 45  wherein the selectively engaging comprises lowering the wafer carrier until one of the refurbishing elements and a wafer abut the polishing pad. 
     
     
       50. The method of  claim 45  wherein one of the refurbishing elements is selectively engaged with deteriorated portions of the polishing pad with accumulations of waste matter. 
     
     
       51. The method of  claim 45  wherein one of the refurbishing elements is selectively engaged and disengaged from the polishing pad as a function of the use of portions of the pad. 
     
     
       52. A pad refurbisher for refurbishing a polishing surface on a polishing pad used in chemical- mechanical polishing of a semiconductor wafer, comprising:      a body adapted for attachment to a wafer carrier of a chemical - mechanical polishing machine with the body having a first ring and a second ring each with a face positioned proximate to a perimeter portion of the wafer carrier and facing the polishing surface of the polishing pad, the body being moveably attached to the wafer carrier; and        a first refurbishment element connected to the face of the first ring and a second refurbishment element connected to the face of the second ring, the first ring operably coupled to a first linear actuator configured to independently move the first ring downwardly to selectively engage the first refurbishment element with the polishing surface and upwardly with respect to the wafer carrier and the second ring to selectively disengage the first refurbishment element from the polishing surface and the second ring operably coupled to a second linear actuator configured to independently move the second ring downwardly to selectively engage the second refurbishment element with the polishing surface and upwardly with respect to the wafer carrier and the first ring to selectively disengage the second refurbishment element from the polishing surface, the first ring being positioned radially outward from the perimeter of the wafer carrier and the second ring being positioned radially outward from the first ring, the first and the second refurbishing elements being adapted to engage the polishing surface substantially adjacent to the perimeter portion of the wafer carrier.     
     
     
       53. The pad refurbisher of  claim 52  wherein the body is fixed to the wafer carrier. 
     
     
       54. The pad refurbisher of  claim 52  wherein the body is slidably attached to the wafer carrier. 
     
     
       55. The pad refurbisher of  claim 52  wherein the first ring and the second ring include a plurality of arcuate segments positioned radially outwardly from the perimeter of the wafer carrier, the arcuate segments being spaced apart from one another around the wafer carrier and each arcuate segment having a distal face facing generally towards the polishing surface of the polishing pad. 
     
     
       56. The pad refurbisher of  claim 52  wherein one of the refurbishing elements is a brush comprising a plurality of bristles extending downwardly from the face towards the polishing surface, the bristles engaging the polishing surface to clean waste particles from the pad. 
     
     
       57. The pad refurbisher of  claim 52  wherein one of the refurbishing elements is a pad conditioner that removes a layer of pad material from polishing surface of the pad to form a new polishing surface on the polishing pad. 
     
     
       58. The pad refurbisher of  claim 57  wherein the pad conditioner comprises a pad with a plurality of embedded diamonds, the pad being connected to the distal surface of the body. 
     
     
       59. The pad refurbisher of  claim 52  wherein the first refurbishing element is a pad cleaner and the second refurbishing element is a pad conditioner. 
     
     
       60. The pad refurbisher of  claim 52  wherein the body is adapted to be symmetrically positioned about the center of the wafer carrier. 
     
     
       61. A polishing machine for chemical- mechanical polishing of a semiconductor wafer, comprising:      a platen having an upper surface;        a polishing pad positioned on the upper surface of the platen, the polishing pad having a polishing surface facing away from the platen;        a wafer carrier for carrying the wafer; and        a pad refurbisher having a body including a first ring bearing a first refurbishment element and a second ring bearing a second refurbishment element, the body being movably attached to the wafer carrier, the first ring operably coupled to a first linear actuator configured to independently move the first ring downwardly to selectively engage the first refurbishment element with the polishing surface and upwardly with respect to the wafer carrier and second ring to selectively disengage the first refurbishment element from the polishing surface and the second ring operably coupled to a second linear actuator configured to independently move the second ring downwardly to selectively engage the second refurbishment element with the polishing surface and upwardly with respect to the wafer carrier and the first ring to selectively disengage the second refurbishment element from the polishing surface, the first ring being positioned radially outward from the perimeter of the wafer carrier and the second ring being positioned radially outward from the first ring.     
     
     
       62. The polishing machine of  claim 61  wherein the first ring comprises a face positioned proximate to a perimeter portion of the wafer carrier and facing generally towards the polishing surface. 
     
     
       63. The polishing machine of  claim 62  wherein the first refurbishing element is connected to the face, and wherein the body being movably attached to the wafer carrier so that the body and the first and the second refurbishing elements travel with the wafer carrier as the wafer carrier moves with respect to the polishing pad, and wherein at least one of the refurbishing elements engages the polishing surface substantially adjacent to the perimeter portion of the wafer carrier while the wafer carrier moves the wafer over the polishing surface. 
     
     
       64. The polishing machine of  claim 61  wherein the body is fixed to the wafer carrier. 
     
     
       65. A method for refurbishing a polishing pad, comprising the steps of:
   providing a pad refurbisher attached to a wafer carrier, the pad refurbisher having a body including a first ring bearing a first refurbishment element and a second ring bearing a second refurbishment element, the body being movably attached to the wafer carrier;        selectively engaging one of the first and the second refurbishing elements with the polishing pad; and        moving at least one of the wafer carrier and the polishing pad with respect to the other to pass at least one of the refurbishing elements across the polishing pad.     
     
     
       66. The method of  claim 65  wherein selectively engaging comprises selectively lowering at least one of the refurbishing elements towards the polishing pad while the wafer carrier presses a wafer against the polishing pad and moves the wafer over the polishing pad to polish the wafer. 
     
     
       67. The method of  claim 65  further comprising selectively disengaging at least one of the refurbishing elements from the pad. 
     
     
       68. The method of  claim 67  wherein the at least one of the refurbishing elements is selectively disengaged from relatively unused portions of the polishing pad not having accumulations of waste matter. 
     
     
       69. The method of  claim 65  wherein the selectively engaging comprises lowering the wafer carrier until one of the refurbishing elements and a wafer abut the polishing pad. 
     
     
       70. The method of  claim 65  wherein one of the refurbishing elements is selectively engaged with deteriorated portions of the polishing pad with accumulations of waste matter. 
     
     
       71. The method of  claim 65  wherein one of the refurbishing elements is selectively engaged and disengaged from the polishing pad as a function of the use of portions of the pad.