Polishing pad and polishing method

Abstract

A polishing pad and a polishing method are described. The polishing pad is made from a composition compresing a polymeric matrix, an additive, and a rheology altering agent. The rheology altering agent enables a uniform distribution of the additive in the polymeric matrix.

1 . A polishing pad having a composition comprising:
 a polymeric matrix;   an additive selected from a group consisting of a low-density additive, a high-density additive, and a combination thereof, and   a rheology altering agent having a structure selected from a group consisting of hydrogen bond bonding, association, spatial orientation, and a combination thereof.   
     
     
         2 . The polishing pad as claimed in  claim 1 , wherein the density difference between the additive and the polymeric matrix is greater than 20% of the density of the polymeric matrix. 
     
     
         3 . The polishing pad as claimed in  claim 1 , wherein the low-density additive comprises a microsphere, a non-reactive gas, or a foaming agent. 
     
     
         4 . The polishing pad as claimed in  claim 1 , wherein the high-density additive comprises abrasive particles. 
     
     
         5 . The polishing pad as claimed in  claim 1 , wherein the rheology altering agent enables the composition to have low viscosity at a shear rate higher than a transitional shear rate and to have high viscosity at a shear rate lower than the transitional shear rate. 
     
     
         6 . The polishing pad as claimed in  claim 1 , wherein the rheology altering agent comprises an inorganic rheology altering agent. 
     
     
         7 . The polishing pad as claimed in  claim 6 , wherein the inorganic rheology altering agent comprises an oxide M x O y  having hydroxyl functional groups (M-OH) on its surface, and M of said oxide M x O y  is selected from a group consisting of silicon, aluminum, titanium, zirconium, cerium, magnesium, calcium, and a combination thereof. 
     
     
         8 . The polishing pad as claimed in  claim 7 , wherein the amount of the hydroxyl functional groups (M-OH) in a unit surface area of the inorganic rheology altering agent ranges from 0.5 M-OH/nm 2  to 2 M-OH/nm 2 . 
     
     
         9 . The polishing pad as claimed in  claim 6 , wherein the inorganic rheology altering agent comprises phyllosilicate. 
     
     
         10 . The polishing pad as claimed in  claim 1 , wherein the rheology altering agent comprises an organic rheology altering agent. 
     
     
         11 . The polishing pad as claimed in  claim 10 , wherein the organic rheology altering agent comprises an emulsifier. 
     
     
         12 . The polishing pad as claimed in  claim 11 , wherein the emulsifier is selected from a group consisting of a cationic emulsifier, an anionic emulsifier, and a non-ionic emulsifier. 
     
     
         13 . The polishing pad as claimed in  claim 10 , wherein the organic rheology altering agent is selected from a group consisting of fatty acid ester, ethylene glycol, polyethylene glycol, propylene glycol, glycerin, polyglycerin, sorbitol, pentaerythritol, glyceride, sucrose, fatty amine, fatty acyl amine, polyglycerol ether, polypropylene glycol ether, and a combination thereof. 
     
     
         14 . The polishing pad as claimed in  claim 10 , wherein the organic rheology altering agent comprises a long chained compound having a polar functional group, and the long chained compound is selected from a group consisting of an acylamide compound, an amide compound, a carbamide compound, a carbamate compound, and a combination thereof. 
     
     
         15 . The polishing pad as claimed in  claim 14 , wherein an average molecular weight of the compound ranges from 5000 to 500000. 
     
     
         16 . The polishing pad as claimed in  claim 10 , wherein the organic rheology altering agent comprises a swellable emulsion. 
     
     
         17 . The polishing pad as claimed in  claim 16 , wherein the organic rheology altering agent comprises a hydrophobically modified alkali swellable emulsion (HASE). 
     
     
         18 . The polishing pad as claimed in  claim 10 , wherein the organic rheology altering agent comprises a polyurethane compound. 
     
     
         19 . The polishing pad as claimed in  claim 18 , wherein the organic rheology altering agent comprises a hydrophobically modified ethylene oxide polyurethane (HEUR). 
     
     
         20 . The polishing pad as claimed in  claim 10 , wherein the rheology altering agent comprises a hydrophobically modified polyether compound. 
     
     
         21 . The polishing pad as claimed in  claim 1 , wherein the weight percentage of the additive in the composition ranges from 0.1% to 30%, while the weight percentage of the rheology altering agent in the composition ranges from 0.5% to 30%. 
     
     
         22 . A polishing pad having a composition comprising:
 a polymeric matrix;   an additive selected from a group consisting of a low-density additive, a high-density additive, and a combination thereof; and   a rheology altering agent enabling the composition to have low viscosity at a shear rate higher than a transitional shear rate and to have high viscosity at a shear rate lower than the transitional shear rate.   
     
     
         23 . The polishing pad as claimed in  claim 22 , wherein the density difference between the additive and the polymeric matrix is greater than 20% of the density of the polymeric matrix. 
     
     
         24 . The polishing pad as claimed in  claim 22 , wherein the low-density additive comprises a microsphere, a non-reactive gas, or a foaming agent. 
     
     
         25 . The polishing pad as claimed in  claim 22 , wherein the high-density additive comprises abrasive particles. 
     
     
         26 . The polishing pad as claimed in  claim 22 , wherein the high viscosity is two times the low viscosity or more. 
     
     
         27 . The polishing pad as claimed in  claim 22 , wherein the rheology altering agent having a structure selected from a group consisting of hydrogen bond bonding, association, spatial orientation, and a combination thereof. 
     
     
         28 . The polishing pad as claimed in  claim 22 , wherein the rheology altering agent comprises an inorganic rheology altering agent. 
     
     
         29 . The polishing pad as claimed in  claim 28 , wherein the inorganic rheology altering agent comprises an oxide M x O y  having hydroxyl functional groups (M-OH) on its surface, and M of the oxide M x O y  is selected from a group consisting of silicon, aluminum, titanium, zirconium, cerium, magnesium, calcium, and a combination thereof. 
     
     
         30 . The polishing pad as claimed in  claim 29 , wherein the amount of the hydroxyl functional groups (M-OH) in a unit surface area of the inorganic rheology altering agent ranges from 0.5 M-OH/nm 2  to 2 M-OH/nm 2 . 
     
     
         31 . The polishing pad as claimed in  claim 28 , wherein the inorganic rheology altering agent comprises phyllosilicate. 
     
     
         32 . The polishing pad as claimed in  claim 22 , wherein the rheology altering agent comprises an organic rheology altering agent. 
     
     
         33 . The polishing pad as claimed in  claim 32 , wherein the organic rheology altering agent comprises an emulsifier. 
     
     
         34 . The polishing pad as claimed in  claim 33 , wherein the emulsifier is selected from a group consisting of a cationic emulsifier, an anionic emulsifier, and a non-ionic emulsifier. 
     
     
         35 . The polishing pad as claimed in  claim 32 , wherein the organic rheology altering agent is selected from a group consisting of fatty acid ester, ethylene glycol, polyethylene glycol, propylene glycol, glycerin, polyglycerin, sorbitol, pentaerythritol, glyceride, sucrose, fatty amine, fatty acyl amine, polyglycerol ether, polypropylene glycol ether, and a combination thereof. 
     
     
         36 . The polishing pad as claimed in  claim 32 , wherein the organic rheology altering agent comprises a long chained compound having a polar functional group, and the long chained compound is selected from a group consisting of an acylamide compound, an amide compound, a carbamide compound, a carbamate compound, and a combination thereof. 
     
     
         37 . The polishing pad as claimed in  claim 36 , wherein an average molecular weight of the compound ranges from 5000 to 500000. 
     
     
         38 . The polishing pad as claimed in  claim 32 , wherein the organic rheology altering agent comprises a swellable emulsion. 
     
     
         39 . The polishing pad as claimed in  claim 38 , wherein the organic rheology altering agent comprises a hydrophobically modified alkali swellable emulsion (HASE). 
     
     
         40 . The polishing pad as claimed in  claim 32 , wherein the organic rheology altering agent comprises a polyurethane compound. 
     
     
         41 . The polishing pad as claimed in  claim 40 , wherein the organic rheology altering agent comprises a hydrophobically modified ethylene oxide polyurethane (HEUR). 
     
     
         42 . The polishing pad as claimed in  claim 32 , wherein the rheology altering agent comprises a hydrophobically modified polyether compound. 
     
     
         43 . The polishing pad as claimed in  claim 22 , wherein the weight percentage of the additive in the composition ranges from 0.1% to 30%, while the weight percentage of the rheology altering agent in the composition ranges from 0.5% to 30%. 
     
     
         44 . A polishing pad, comprising:
 a polymeric matrix;   a network structure constructed by a rheology altering agent in the polymeric matrix; and   an additive distributed in the polymeric matrix, the additive being selected from a group consisting of a low-density additive, a high-density additive, and a combination thereof.   
     
     
         45 . The polishing pad as claimed in  claim 44 , wherein the rheology altering agent having a structure selected from a group consisting of hydrogen bond bonding, association, spatial orientation, and a combination thereof. 
     
     
         46 . The polishing pad as claimed in  claim 44 , wherein the additive is isolated by the network structure. 
     
     
         47 . The polishing pad as claimed in  claim 44 , wherein the density in different areas of the polishing pad has less density variations than a polishing pad in which the additive is in the same amount but no rheology altering agent is formed. 
     
     
         48 . The polishing pad as claimed in  claim 44 , wherein the additive of the polishing pad is agglomerated to a less extent in comparison with a polishing pad in which the additive is in the same amount but no rheology altering agent is formed. 
     
     
         49 . A polishing method suitable for polishing a substrate, the polishing method comprising:
 providing a polishing pad;   applying a pressure to a substrate to press the substrate onto the polishing pad; and   relatively moving the substrate and the polishing pad, wherein the polishing pad has a composition comprising:
 a polymeric matrix; 
 an additive selected from a group consisting of a low-density additive, a high-density additive, and a combination thereof; and 
 a rheology altering agent having a structure selected from a group consisting of hydrogen bond bonding, association, spatial orientation, and a combination thereof. 
   
     
     
         50 . A polishing method suitable for polishing a substrate, the polishing method comprising:
 providing a polishing pad;   applying a pressure to a substrate to press the substrate onto the polishing pad; and   relatively moving the substrate and the polishing pad, wherein the polishing pad has a composition comprising:
 a polymeric matrix; 
 an additive selected from a group consisting of a low-density additive, a high-density additive, and a combination thereof; and 
 a rheology altering agent enabling the composition to have low viscosity at a shear rate higher than a transitional shear rate and to have high viscosity at a shear rate lower than the transitional shear rate. 
   
     
     
         51 . A polishing method suitable for polishing a substrate, the polishing method comprising:
 providing a polishing pad;   applying a pressure to a substrate to press the substrate onto the polishing pad; and   relatively moving the substrate and the polishing pad, wherein the polishing pad comprising:
 a polymeric matrix; 
 a network structure constructed by a rheology altering agent in the polymeric matrix; and 
 an additive distributed in the polymeric matrix, the additive being selected from a group consisting of a low-density additive, a high-density additive, and a combination thereof.