Cmp apparatus and method

Abstract

A CMP apparatus includes an enclosure; a platen disposed within the enclosure, and a carrier for holding and rotating a wafer. The platen consists of a central, circular-shaped segment and a peripheral, annular-shaped segment with a gap formed therebetween. A first polishing pad is mounted on the central, circular-shaped segment. A second polishing pad is mounted on the peripheral, annular-shaped segment. In polishing, the carrier rotates between the first and second polishing pads, such that an annular edge region of the wafer is in direct contact with the second polishing pad.

1 . A CMP apparatus, comprising:
 an enclosure;   a platen disposed within the enclosure, wherein the platen consists of a central, circular-shaped segment and a peripheral, annular-shaped segment encircling the central, circular-shaped segment with a gap therebetween;   a carrier for holding and rotating a wafer;   a first polishing pad mounted on the central, circular-shaped segment; and   a second polishing pad mounted on the peripheral, annular-shaped segment.   
     
     
         2 . The CMP apparatus according to  claim 1  further comprising:
 a first nozzle for supplying a first slurry onto the first polishing pad; and 
 a second nozzle for supplying a second slurry onto the second polishing pad. 
 
     
     
         3 . The CMP apparatus according to  claim 2  wherein the first slurry and the second slurry are supplied at different flow rates. 
     
     
         4 . The CMP apparatus according to  claim 2  wherein the first slurry and the second slurry have different concentration settings. 
     
     
         5 . The CMP apparatus according to  claim 1  wherein the gap has a width d of about 0.5-5 mm. 
     
     
         6 . The CMP apparatus according to  claim 1  wherein the central, circular-shaped segment and the peripheral, annular-shaped segment rotate in the same direction. 
     
     
         7 . The CMP apparatus according to  claim 1  wherein the central, circular-shaped segment and the peripheral, annular-shaped segment rotate at different rotation speeds. 
     
     
         8 . The CMP apparatus according to  claim 7  wherein the rotation speed of the peripheral, annular-shaped segment is slower than that of the central, circular-shaped segment. 
     
     
         9 . The CMP apparatus according to  claim 1  wherein in polishing the carrier rotates between the first and second polishing pads, such that an annular edge region of the wafer is in direct contact with the second polishing pad. 
     
     
         10 . The CMP apparatus according to  claim 9  wherein a surface area of the annular edge region is about one-third of a total surface area of the wafer.