Polishing pad and method of manufacturing the same

Abstract

Polishing pad and method of manufacturing the same, the method including: (a) mixing materials for forming a polishing layer; (b) mixing at least two from among inert gas, a capsule type foaming agent, a chemical foaming agent, and liquid microelements that are capable of controlling sizes of pores, with the mixture in (a) so as to form two or more types of pores; (c) performing gelling and hardening of the mixture generated in (b) so as to form a polishing layer including the two or more types of pores; and (d) processing the polishing layer so as to distribute micropores defined by opening the two or more types of pores on a surface of the polishing layer.

What is claimed is: 
     
         1 . A method of manufacturing a polishing pad, the method comprising:
 (a) mixing materials for forming a polishing layer;   (b) mixing at least two from among inert gas, a capsule type foaming agent, a chemical foaming agent, and liquid microelements that are capable of controlling sizes of pores, with the mixture in (a) so as to form two or more types of pores;   (c) performing gelling and hardening of the mixture generated in (b) so as to form a polishing layer comprising the two or more types of pores; and   (d) processing the polishing layer so as to distribute micropores defined by opening the two or more types of pores on a surface of the polishing layer.   
     
     
         2 . The method of  claim 1 , wherein the inert gas is selected from the group consisting of 8 group elements of a periodic table and gas that does not react with the materials for forming the polishing layer. 
     
     
         3 . The method of  claim 1 , wherein a liquid material that constitutes the liquid microelements comprises at least one selected from the group consisting of aliphatic mineral oil, aromatic mineral oil, a silicon oil which does not have a hydroxyl group at the end of molecules, soybean oil, coconut oil, palm oil, cotton seed oil, camellia oil, hardened oil, or a combination thereof. 
     
     
         4 . A polishing pad that performs a polishing process by moving in contact with a surface of an object to be polished, the polishing pad comprising a polishing layer,
 wherein the polishing layer comprises two or more types of pores, of which sizes are controlled by using at least two from among inert gas, a capsule type foaming agent, a chemical agent, and liquid microelements, and   micropores that are defined by opening the two or more types of pores are distributed on a surface of the polishing layer.   
     
     
         5 . The polishing pad of  claim 4 , wherein the inert gas is selected from the group consisting of 8 group elements of a periodic table and gas that does not react with the materials for forming the polishing layer. 
     
     
         6 . The polishing pad of  claim 4 , wherein a liquid material that constitutes the liquid microelements comprises at least one selected from the group consisting of aliphatic mineral oil, aromatic mineral oil, a silicon oil which does not have a hydroxyl group at the end of molecules, soybean oil, coconut oil, palm oil, cotton seed oil, camellia oil, hardened oil, or a combination thereof. 
     
     
         7 . The polishing pad of  claim 4 , wherein the polishing layer comprises a plurality of first pores formed by the liquid microelements and a plurality of second pores having a relatively large size and formed by using at least one from among injecting the inert gas, injecting the capsule type foaming agent, and injecting the chemical foaming agent.