Apparatus and method for chemical mechanical planarization using a fixed-abrasive polishing pad

Abstract

A homogeneous polishing pad for chemical mechanical planarization of a workpiece has a thickness of at least about 1 millimeter. The polishing pad is friable and includes an abrasive material that is uniformly distributed throughout the pad. The abrasive material exhibits abrasive behavior that does not degrade significantly as the pad wears during planarization and conditioning. In another embodiment, the homogenous polishing pad has an average wear rate in the range of from less than 1 μm/minute to about 10 μm/minute.

We claim:  
     
         1 . A homogenous polishing pad for chemical mechanical planarization of a workpiece having a thickness of at least about 1 millimeter, wherein said pad is friable and comprises an abrasive material uniformly distributed throughout said pad, and wherein said abrasive material has abrasive characteristics that do not degrade significantly as said pad wears during planarization and conditioning.  
     
     
         2 . The polishing pad of  claim 1 , further comprising a resin-bonded material.  
     
     
         3 . The polishing pad of  claim 1 , further comprising a ceramic-bonded material.  
     
     
         4 . The polishing pad of  claim 1  having a thickness in the range of from about 0.5 inches to about 1.5 inches.  
     
     
         5 . The polishing pad of  claim 1  having a thickness of about one inch.  
     
     
         6 . The polishing pad of  claim 1 , wherein said polishing pad is subjected to motion relative to said workpiece.  
     
     
         7 . The polishing pad of  claim 6 , wherein said motion is selected from the group comprising linear motion, orbital motion, rotary motion, linear and orbital motion, linear and rotary motion, orbital and rotary motion, and linear, orbital and rotary motion.  
     
     
         8 . The polishing pad of  claim 1 , further comprising at least one channel through which a fluid may flow.  
     
     
         9 . The polishing pad of  claim 1 , wherein said polishing pad comprises pores through which a fluid may flow.  
     
     
         10 . The polishing pad of  claim 1  having an average wear rate in the range of from less than 1 μm/minute to about 10 μm/minute.  
     
     
         11 . A method of chemical mechanical planarization of a workpiece comprising: 
 providing a homogenous polishing pad having a thickness of at least about 1 millimeter and having a polishing surface, wherein said polishing pad is friable and comprises abrasive material uniformly distributed throughout said polishing pad, and wherein said abrasive material exhibits abrasive behavior that does not degrade significantly as said polishing pad wears during planarizaton and conditioning; and    pressing said polishing pad against said workpiece while causing relative motion between said polishing pad and said workpiece.    
     
     
         12 . The method of  claim 11 , further comprising distributing a fluid to said polishing surface of said polishing pad.  
     
     
         13 . The method of  claim 11 , wherein said causing relative motion comprises causing relative motion selected from the group comprising linear motion, orbital motion, rotary motion, linear and orbital motion, linear and rotary motion, orbital and rotary motion, and linear, orbital and rotary motion.  
     
     
         14 . The method of  claim 11 , wherein said providing a homogenous polishing pad further comprises providing a homogenous polishing pad having a thickness in the range of from about 0.5 inches to about 1.5 inches.  
     
     
         15 . The method of  claim 11 , wherein said providing a homogenous polishing pad further comprises providing a homogenous polishing pad having a thickness of about one inch.  
     
     
         16 . The method of  claim 12 , wherein said providing a homogeneous polishing pad further comprises providing a homogeneous polishing pad having at least one channel through which said fluid may flow.  
     
     
         17 . The method of  claim 12 , wherein said providing a homogeneous polishing pad further comprises providing a homogeneous polishing pad having pores through which said fluid may flow.  
     
     
         18 . The method of  claim 11 , wherein said providing a homogeneous polishing pad further comprises providing a homogeneous polishing pad having an average pad wear rate in the range of from less than 1 m/minute to about 10 μm/minute.  
     
     
         19 . An apparatus for planarizing a workpiece comprising: 
 a homogenous polishing pad having a thickness of at least about 1 millimeter, wherein said pad is friable and comprises abrasive material uniformly distributed throughout, and wherein said abrasive material exhibits abrasive behavior that does not degrade significantly as said homogeneous polishing pad wears during planarization and conditioning; and    a workpiece carrier configured to carry a workpiece and press said workpiece against said homogeneous polishing pad.    
     
     
         20 . The apparatus of  claim 19 , wherein said polishing pad has a thickness in the range of from about 0.5 inches to about 1.5 inches.  
     
     
         21 . The apparatus of  claim 19 , wherein said polishing pad has a thickness of about one inch.  
     
     
         22 . The apparatus of  claim 19 , further comprising a drive assembly configured to cause relative motion between said polishing pad and said workpiece.  
     
     
         23 . The apparatus of  claim 22 , wherein said relative motion is selected from the group comprising linear motion, orbital motion, rotary motion, linear and orbital motion, linear and rotary motion, orbital and rotary motion, and linear, orbital and rotary motion.  
     
     
         24 . The apparatus of  claim 19 , wherein said workpiece carrier comprises a central axis and is configured to rotate about said central axis.  
     
     
         25 . The apparatus of  claim 19 , wherein said homogeneous polishing pad has a polishing surface and at least one channel wherein fluids are fed to said polishing surface through said at least one channel.  
     
     
         26 . The apparatus of  claim 25 , further comprising a platen configured to support said polishing pad.  
     
     
         27 . The apparatus of  claim 26 , wherein said platen comprises at least one conduit and wherein fluids are fed to said polishing surface through said at least one conduit of said platen and said at least one channel of said homogeneous polishing pad.  
     
     
         28 . The apparatus of  claim 19 , wherein said homogeneous polishing pad has a polishing surface and comprises pores wherein fluids are fed to said polishing surface through said pores.  
     
     
         29 . The apparatus of  claim 28 , further comprising a platen configured to support said polishing pad.  
     
     
         30 . The apparatus of  claim 29 , wherein said platen comprises at least one conduit and wherein fluids are fed to said polishing surface through said at least one conduit of said platen and said pores of said homogeneous polishing pad.  
     
     
         31 . The apparatus of  claim 19 , wherein said homogeneous polishing pad has an average wear rate in the range of from less than 1 μm/minute to about 10 μm/minute.  
     
     
         32 . A homogeneous polishing pad for chemical mechanical planarization of a workpiece having an average wear rate in the range of from less than 1 μm/minute to about 10 μm/minute, wherein said pad is friable and comprises an abrasive material uniformly distributed throughout said pad, and wherein said abrasive material has abrasive characteristics that do not degrade significantly as said pad wears during planarization and conditioning.  
     
     
         33 . The polishing pad of  claim 32 , further comprising a resin-bonded material.  
     
     
         34 . The polishing pad of  claim 32 , further comprising a ceramic-bonded material.  
     
     
         35 . The polishing pad of  claim 32 , having a thickness in the range of from about 0.5 inches to about 1.5 inches.  
     
     
         36 . The polishing pad of  claim 32 , having a thickness of about one inch.  
     
     
         37 . The polishing pad of  claim 32 , wherein said polishing pad is subjected to motion relative to said workpiece.  
     
     
         38 . The polishing pad of  claim 37 , wherein said motion is selected from the group comprising linear motion, orbital motion, rotary motion, linear and orbital motion, linear and rotary motion, orbital and rotary motion, and linear, orbital and rotary motion.  
     
     
         39 . The polishing pad of  claim 32 , further comprising at least one channel through which a fluid may flow.  
     
     
         40 . The polishing pad of  claim 32 , further comprising pores through which a fluid may flow.  
     
     
         41 . An apparatus for planarizing a workpiece comprising: 
 a) a plurality of polishing stations wherein at least one of said plurality of polishing stations comprises a homogenous polishing pad having a thickness of at least about 1 millimeter, wherein said homogenous polishing pad is friable and comprises abrasive material uniformly distributed throughout, and wherein said abrasive material has abrasive characteristics that do not degrade significantly as said polishing pad wears during planarization and conditioning;    and    b) a drive assembly connected to said at least one of said plurality of polishing stations and configured to effect a first relative motion between said homogenous polishing pad and said workpiece.    
     
     
         42 . The apparatus of  claim 41 , wherein said first relative motion is selected from the group comprising linear motion, orbital motion, rotary motion, linear and orbital motion, linear and rotary motion, orbital and rotary motion, and linear, orbital and rotary motion.  
     
     
         43 . The apparatus of  claim 41 , wherein said homogenous polishing pad further comprises a resin-bonded material.  
     
     
         44 . The apparatus of  claim 41 , wherein said homogenous polishing pad further comprises a ceramic-bonded material.  
     
     
         45 . The apparatus of  claim 41 , wherein said homogenous polishing pad has a thickness in the range of from about 0.5 inches to about 1.5 inches.  
     
     
         46 . The apparatus of  claim 41 , wherein said homogenous polishing pad has a thickness of about one inch.  
     
     
         47 . The apparatus of  claim 41 , wherein said homogenous polishing pad has a least one channel through which a fluid may flow.  
     
     
         48 . The apparatus of  claim 41 , wherein said polishing pad comprises pores through which a fluid may flow.  
     
     
         49 . The apparatus of  claim 41 , wherein said polishing pad has an average wear rate in the range of from less than 1 μm/minute to about 10 μm/minute.  
     
     
         50 . The apparatus of  claim 41 , further comprising a conditioning assembly configured to condition said homogenous polishing pad after planarization of a workpiece.  
     
     
         51 . The apparatus of  claim 41 , further comprising a conditioning assembly configured to condition said homogenous polishing pad during planarization of a workpiece.  
     
     
         52 . The apparatus of  claim 41 , further comprising a plurality of workpiece carriers, the number of which corresponds to the number of said polishing stations, wherein each of said plurality of workpiece carriers is configured to carry a workpiece and press said workpiece against one of said plurality of polishing stations while causing a second relative motion between said workpiece and said polishing station.  
     
     
         53 . The apparatus of  claim 52 , wherein said second relative motion is selected from the group comprising linear motion, orbital motion, rotary motion, linear and orbital motion, linear and rotary motion, orbital and rotary motion, and linear, orbital and rotary motion.  
     
     
         54 . The apparatus of  claim 41 , wherein said homogenous polishing pad has a polishing surface and at least one channel through which fluids are fed to said polishing surface.  
     
     
         55 . The apparatus of  claim 54 , wherein said at least one of said plurality of polishing stations comprises a platen configured to support said homogenous polishing pad.  
     
     
         56 . The apparatus of  claim 55 , wherein said platen comprises at least one conduit and wherein fluids are fed to said polishing surface through said at least one conduit and said at least one channel of said polishing pad.  
     
     
         57 . The apparatus of  claim 41 , wherein said homogeneous polishing pad has a polishing surface and comprises pores wherein fluids are fed to said polishing surface through said pores.  
     
     
         58 . The apparatus of  claim 57 , further comprising platen configured to support said polishing pad.  
     
     
         59 . The apparatus of  claim 58 , wherein said platen comprises at least one conduit and wherein fluids are fed to said polishing surface through said at least one conduit of said platen and said pores of said homogeneous polishing pad.  
     
     
         60 . An apparatus for planarizing a workpiece comprising: 
 a homogeneous polishing pad, wherein said polishing pad is friable and has abrasive material uniformly distributed throughout, and wherein said abrasive material exhibits abrasive behavior that does not degrade significantly as said homogeneous polishing pad wears during planarization and conditioning;    a drive assembly configured to move said polishing pad in an orbital pattern; and    a workpiece carrier configured to carry a workpiece and press said workpiece against said homogeneous polishing pad.    
     
     
         61 . The apparatus of  claim 60 , wherein said polishing pad has a thickness of at least 1 millimeter.  
     
     
         62 . The apparatus of  claim 60 , wherein said polishing pad has a thickness in the range of from about 0.5 inches to about 1.5 inches.  
     
     
         63 . The apparatus of  claim 60 , wherein said polishing pad has a thickness of about one inch.  
     
     
         64 . The apparatus of  claim 60 , wherein said workpiece carrier comprises a central axis and is configured to rotate about said central axis.  
     
     
         65 . The apparatus of  claim 60 , wherein said homogeneous polishing pad has a polishing surface and at least one channel wherein fluids are fed to said polishing surface through said at least one channel.  
     
     
         66 . The apparatus of  claim 65 , further comprising a platen configured to support the polishing pad.  
     
     
         67 . The apparatus of  claim 66 , wherein said platen comprises at least one conduit and wherein a fluid is fed to said polishing surface through said at least one conduit and said at least one channel.  
     
     
         68 . The apparatus of  claim 60 , wherein said homogeneous polishing pad has pores through which a fluid may flow.  
     
     
         69 . The apparatus of claim  72 , further comprising a platen configured to support the polishing pad.  
     
     
         70 . The apparatus of  claim 69 , wherein said platen comprises at least one conduit and wherein a fluid is fed to said polishing surface through said at least one conduit and said pores.  
     
     
         71 . The apparatus of  claim 60 , wherein said homogeneous polishing pad has an average wear rate in the range from less than 1 μm/minute to about 10 μm/minute.