Polishing pad for wafer polishing apparatus

Abstract

A polishing pad for a wafer polishing apparatus according to an embodiment includes: a first NAP layer having an upper surface in direct contact with a wafer; a second NAP layer disposed under the first NAP layer to support the first NAP layer; and a polyethylene terephthalate film (PET film) layer disposed under the second NAP layer to be attached to a surface plate.

What is claimed is: 
     
         1 . A polishing pad for a wafer polishing apparatus comprising:
 a first NAP layer having an upper surface in direct contact with a wafer;
 a second NAP layer disposed under the first NAP layer to support the first NAP layer; and 
 a polyethylene terephthalate film (PET film) layer disposed under the second NAP layer to be attached to a surface plate. 
   
     
     
         2 . The polishing pad for the wafer polishing apparatus of  claim 1 , wherein a compressibility of the first NAP layer is 12% or less. 
     
     
         3 . The polishing pad for the wafer polishing apparatus of  claim 1 , wherein a hardness of the first NAP layer is 22° or more. 
     
     
         4 . The polishing pad for the wafer polishing apparatus of  claim 1 , wherein a compressibility of the second NAP layer is 10% to 30%. 
     
     
         5 . The polishing pad for the wafer polishing apparatus of  claim 1 , wherein an elastic modulus of the second NAP layer is 95% or more. 
     
     
         6 . The polishing pad for the wafer polishing apparatus of  claim 1 , wherein a hardness of the second NAP layer is 19° to 26°. 
     
     
         7 . The polishing pad for the wafer polishing apparatus of  claim 1 , wherein thicknesses of the first and second NAP layers are 0.30 to 0.40 mm, respectively. 
     
     
         8 . The polishing pad for the wafer polishing apparatus of  claim 1 , wherein a thickness of the PET film layer is 0.10 to 0.30 mm. 
     
     
         9 . The polishing pad for the wafer polishing apparatus of  claim 1 , wherein the first and second NAP layers are a suede material including polyurethane. 
     
     
         10 . The polishing pad for the wafer polishing apparatus of  claim 1 , further comprising an adhesive layer for combining the first NAP layer and the second NAP layer.