Chemical-mechanical planarization (cmp) pad conditioner brush-and-abrasive hybrid for multi-step, preparation- and restoration-conditioning process of cmp pad

Abstract

A multi-step conditioning process includes an initial step of preparation (i.e., pre-conditioning) and a subsequent step of restoration (i.e., conditioning and polishing intermittently, in situ conditioning, or combinations thereof). An example of such an enhancement is achieved using a CMP pad conditioner brush-and-abrasive hybrid that has a combination of brush bristles and abrasive elements. The abrasive elements are readily deployed for pre-conditioning as the brush bristles are pressed (flexed) so that they are not in use. And the brush bristles are readily deployed for conditioning during pad restoration as less downforce is applied to the conditioner. Thus, a universal hybrid conditioner is capable of alteration of its aggressiveness without physically changing a conditioner on a polisher tool.

1 . A chemical-mechanical planarization (CMP) pad conditioner, comprising:
 a base having a major surface;   
       an abrasive portion depending from the major surface and having an abrasive surface parallel to the major surface; and
 a brush portion affixed to the major surface so as to substantially encompass the abrasive portion, the brush portion having brush bristles depending away from the major surface to define a brush surface, in which, in a CMP pad pre-conditioning configuration, the brush surface is compressible so as to be at a first height that is substantially similar to that of the abrasive surface, and, in a CMP pad restoration configuration, the brush surface is substantially uncompressed so as to be at a height that extends past that of the abrasive surface. 
 
     
     
         2 . The CMP pad conditioner of  claim 1 , in which the brush bristles comprise angled bristles. 
     
     
         3 . The CMP pad conditioner of  claim 1 , in which the brush bristles comprise straight bristles. 
     
     
         4 . The CMP pad conditioner of  claim 1 , in which the brush bristles comprise nylon bristles. 
     
     
         5 . The CMP pad conditioner of  claim 1 , in which the abrasive surface is configured to contact a polishing pad in response to a force applied to flex the brush bristles. 
     
     
         6 . The CMP pad conditioner of  claim 5 , in which the force that configures the abrasive surface to contact the polishing pad is between about two pounds-force per square inch (PSI), 13789.5 Pascal (Pa) and about six PSI, 34473.8 Pa. 
     
     
         7 . The CMP pad conditioner of  claim 5 , in which the force is about six PSI, 34473.8 Pa. 
     
     
         8 . The CMP pad conditioner of  claim 1 , in which the base comprises a ceramic base. 
     
     
         9 . A system for polishing a surface of a workpiece, the system comprising:
 a chemical-mechanical planarization (CMP) polishing pad having a pad surface;   a pad conditioning assembly; and   a CMP pad conditioner brush-and-abrasive hybrid tool comprising:   an abrasive portion depending toward the pad surface and having an abrasive surface parallel to the pad surface; and   a brush portion in a region of the CMP pad conditioner brush-and-abrasive hybrid tool adjacent the abrasive portion, the brush portion having brush bristles depending toward the pad surface to define a brush surface, in which, in a CMP pad pre-conditioning configuration, the brush surface is under a first force to press the abrasive surface against the pad surface such that the brush bristles flex to move the brush surface to be at a first height that is substantially similar to that of the abrasive surface, and, in a CMP pad restoration configuration, the brush surface is under a second force less than the first force to maintain the abrasive portion in a recessed position relative to the brush portion, and the brush surface is at a second height that extends past that of the abrasive surface.   
     
     
         10 . The system of  claim 9 , in which the brush bristles comprise angled bristles. 
     
     
         11 . The system of  claim 9 , in which the brush bristles comprise straight bristles. 
     
     
         12 . The system of  claim 9 , in which the brush bristles comprise nylon bristles configured to flex under downforce applied by the pad conditioning assembly. 
     
     
         13 . The system of  claim 9 , in which the abrasive surface is configured to contact the pad surface in response to a force applied to flex the brush bristles. 
     
     
         14 . The system of  claim 13 , in which the force that configures the abrasive surface to contact the pad surface is between about two pounds-force per square inch (PSI), 13789.5 Pascal (Pa) and about six PSI, 34473.8 Pa. 
     
     
         15 . The system of  claim 13 , in which the force is about six PSI, 34473.8 Pa. 
     
     
         16 . The system of  claim 9 , in which the abrasive portion comprises a plurality of ceramic disks. 
     
     
         17 . A method of reducing tool time by preparing and restoring a chemical-mechanical planarization (CMP) pad using a CMP pad conditioner brush-and-abrasive hybrid tool, the method comprising:
 preparing the CMP pad using a disk portion of the CMP pad conditioner brush-and-abrasive hybrid tool by applying a first downforce to the CMP pad conditioner brush-and-abrasive hybrid tool; and   restoring the CMP pad using a brush portion of the CMP pad conditioner brush-and-abrasive hybrid tool by applying a second downforce to the CMP pad conditioner brush-and-abrasive hybrid tool, the second downforce being less than the first downforce such that the disk portion does not contact the CMP pad during the restoring.   
     
     
         18 . The method of  claim 17 , further comprising restoring the CMP pad by conditioning in situ during a polishing process. 
     
     
         19 . The method of  claim 17 , further comprising restoring the CMP pad by conditioning intermittently between conditioning and polishing steps of a polishing process. 
     
     
         20 . The method of  claim 17 , further comprising preparing the CMP pad by conditioning for a duration of about 12 to about 35 minutes under about two pounds-force per square inch (PSI) 13789.5, Pascal (Pa) to about six PSI, 34473.8 Pa. 
     
     
         21 . The method of  claim 17 , in which the first downforce is about two pounds-force per square inch (PSI), 13789.5 Pascal (Pa) to about six PSI, 34473.8 Pa. 
     
     
         22 . The method of  claim 17 , in which the brush portion includes non-straight bristles. 
     
     
         23 . The method of  claim 17 , in which the brush portion includes substantially straight bristles.