Polishing composition and polishing method

Abstract

Disclosed is a polishing composition containing a pH-lowering substance and a pH-buffering agent. The difference in absolute value between the pH of the polishing composition immediately after adding a 31% by weight hydrogen peroxide solution thereto at 5.16 g per 100 g of the polishing composition and the pH of the polishing composition after leaving to stand for eight days therefrom is 0.5 or less. Also disclosed is another polishing composition containing a pH-lowering substance and a pH-controlling agent. In comparison to the amount of a basic substance in the polishing composition immediately after adding a 31% by weight hydrogen peroxide solution thereto at 5.16 g per 100 ml of the polishing composition, the amount of a basic substance in the polishing composition after leaving to stand for eight days therefrom is increased by no less than 0.1 mM.

1 . A polishing composition comprising:
 a substance that lowers the pH of an aqueous solution in the presence of an oxidizing agent; and   a pH-buffering agent,   wherein the difference in absolute value between the pH of the polishing composition immediately after adding a 31% by weight hydrogen peroxide solution thereto at 5.16 g per 100 g of the polishing composition and the pH of the polishing composition after leaving to stand for eight days from the addition of the hydrogen peroxide solution is 0.5 or less.   
     
     
         2 . The polishing composition according to  claim 1 , wherein the pH-buffering agent is a compound having an amide group. 
     
     
         3 . The polishing composition according to  claim 1 , wherein the pH-buffering agent is an amphoteric amino acid having at least one of a sulfo group and a carboxyl group. 
     
     
         4 . The polishing composition according to  claim 1 , wherein the pH-buffering agent is a compound represented by the following general formula (1), in which R 1  and R 3  each independently represent a non-substituted or substituted straight-chain alkyl group with 1 to 4 carbon atoms, R 2  represents a hydrogen atom, a hydroxyl group, a sulfo group, a carboxyl group, an amino group, an amide group, a carbamoyl group, a nitro group, a methoxy group, an ethoxy group, a halogen group, a phenyl group, an acetyl group, or a non-substituted or substituted alkyl group with 1 to 4 carbon atoms, and X represents a sulfo group, a carboxyl group, or a salt thereof. 
       
         
           
           
               
               
           
         
       
     
     
         5 . The polishing composition according to  claim 4 , wherein in the general formula (1), X is a sulfo group or a salt thereof. 
     
     
         6 . A polishing composition comprising:
 a substance that lowers the pH of an aqueous solution in the presence of an oxidizing agent; and   a pH-controlling agent,   wherein in comparison to the amount of a basic substance in the polishing composition immediately after adding a 31% by weight hydrogen peroxide solution thereto at 5.16 g per 100 ml of the polishing composition, the amount of a basic substance in the polishing composition after leaving to stand for eight days from the addition of the hydrogen peroxide solution is increased by no less than 0.1 mM.   
     
     
         7 . The polishing composition according to  claim 6 , wherein the difference in absolute value between the pH of the polishing composition immediately after adding a 31% by weight hydrogen peroxide solution thereto at 5.16 g per 100 ml of the polishing composition and the pH of the polishing composition after leaving to stand for eight days from the addition of the hydrogen peroxide solution is 0.5 or less. 
     
     
         8 . The polishing composition according to  claim 6 , wherein the basic compound is ammonia. 
     
     
         9 . The polishing composition according to  claim 6 , wherein in comparison to the amount of a basic substance in a 100 ml of aqueous solution containing 5.0 mM of the pH-controlling agent immediately after adding 10.32 g of a 31% by weight hydrogen peroxide solution thereto, the amount of a basic substance in the aqueous solution after leaving to stand for eight days from the addition of the hydrogen peroxide solution is increased by no less than 0.2 mM. 
     
     
         10 . The polishing composition according to  claim 6 , wherein the pH-controlling agent is a compound having an amide group. 
     
     
         11 . The polishing composition according to  claim 6 , wherein the pH-controlling agent is an amphoteric amino acid having at least one of a sulfo group and a carboxyl group. 
     
     
         12 . The polishing composition according to  claim 6 , wherein the pH-controlling agent is a compound represented by the following general formula (2), in which R 1  and R 3  each independently represent a non-substituted or substituted straight-chain alkyl group with 1 to 4 carbon atoms, R 2  represents a hydrogen atom, a hydroxyl group, a sulfo group, a phosphono group, a carboxyl group, an amino group, an amide group, a carbamoyl group, a nitro group, a methoxy group, an ethoxy group, a halogen group, a phenyl group, an acetyl group, an acyl group, or a non-substituted or substituted alkyl group with 1 to 4 carbon atoms, and X represents a sulfo group, a carboxyl group, or a salt thereof 
       
         
           
           
               
               
           
         
       
     
     
         13 . The polishing composition according to  claim 12  wherein in the general formula (2), X is a sulfo group or a salt thereof. 
     
     
         14 . A polishing method comprising:
 providing a metal to be polished; and   using a polishing composition to polish the metal, wherein the polishing composition contains a substance that lowers the pH of an aqueous solution in the presence of an oxidizing agent, and a pH-buffering agent, and wherein the difference in absolute value between the pH of the polishing composition immediately after adding a 31% by weight hydrogen peroxide solution thereto at 5.16 g per 100 g of the polishing composition and the pH of the polishing composition after leaving to stand for eight days from the addition of the hydrogen peroxide solution is no more than 0.5.   
     
     
         15 . The polishing method according to  claim 14 , further comprising adding an oxidizing agent to the polishing composition prior to said using. 
     
     
         16 . A method of producing a metal-containing substrate, comprising:
 providing a metal to be polished; and   polishing the metal with a polishing composition containing a substance that lowers the pH of an aqueous solution in the presence of an oxidizing agent, and a pH-buffering agent, wherein the difference in absolute value between the pH of the polishing composition immediately after adding a 31% by weight hydrogen peroxide solution thereto at 5.16 g per 100 g of the polishing composition and the pH of the polishing composition after leaving to stand for eight days from the addition of the hydrogen peroxide solution is no more than 0.5.   
     
     
         17 . A polishing method comprising:
 providing a metal to be polished; and   using a polishing composition to polish the metal, wherein the polishing composition contains a substance that lowers the pH of an aqueous solution in the presence of an oxidizing agent, and a pH-controlling agent, wherein in comparison to the amount of a basic substance in the polishing composition immediately after adding a 31% by weight hydrogen peroxide solution thereto at 5.16 g per 100 ml of the polishing composition, the amount of a basic substance in the polishing composition after leaving to stand for eight days from the addition of the hydrogen peroxide solution is increased by no less than 0.1 mM.   
     
     
         18 . The polishing method according to  claim 17 , further comprising adding an oxidizing agent to the polishing composition prior to said using. 
     
     
         19 . A method of producing a metal-containing substrate, comprising:
 providing a metal to be polished; and   polishing the metal with a polishing composition containing a substance that lowers the pH of an aqueous solution in the presence of an oxidizing agent, and a pH-controlling agent, wherein in comparison to the amount of a basic substance in the polishing composition immediately after adding a 31% by weight hydrogen peroxide solution thereto at 5.16 g per 100 ml of the polishing composition, the amount of a basic substance in the polishing composition after leaving to stand for eight days from the addition of the hydrogen peroxide solution is increased by no less than 0.1 mM.