Abrasive free formulations for chemical mechanical polishing of copper and associated materials and method of using same

Abstract

An abrasive free formulation for chemical mechanical polishing and method for using the formulation for polishing copper and related materials. The abrasive free formulation has a high removal rate on copper and a low removal rate on barrier material. The abrasive free formulation comprises at least an oxidizing agent and an activating agent.

1 - 38 . (canceled)  
   
   
       39 . A polishing method for removing at least a portion of a metal film, comprising mechanically rubbing a metal film surface using a chemical mechanical polishing formulation comprising an oxidizing agent and a corrosion inhibitor said formulation having a pH in the range of from about 0.1 to 6.9.  
   
   
       40 . The polishing method according to  claim 39 , wherein the oxidizing agent is an iodate salt.  
   
   
       41 . The polishing method according to  claim 39 , wherein the oxidizing agent is selected from the group consisting of hydrogen peroxide, potassium iodate, ferric nitrate, ammonium chlorite, ammonium chlorate, ammonium iodate, ammonium perborate, ammonium perchlorate, ammonium periodate ammonium persulfate, tetramethylammonium chlorite, tetramethylammonium chlorate, tetramethylammonium iodate, tetramethylammonium perborate, tetramethylammonium perchlorate, tetramethylammonium periodate, tetramethylammonium persulfate, urea hydrogen peroxide, 4-methylmorpholine N-oxide (C 5 H 11 NO 2 ) and pyridine N-oxide (C 5 H 5 NO).  
   
   
       42 . The polishing method according to  claim 39 , wherein the corrosion inhibitor is a carboxylic acid.  
   
   
       43 . The polishing method according to  claim 39 , wherein the corrosion inhibitor is selected from the group consisting of glycine, oxalic acid, malonic acid, succinic acid and nitrilotriacetic acid.  
   
   
       44 . The polishing method according to  claim 39 , wherein the corrosion inhibitor is a dicarboxylic acid.  
   
   
       45 . The polishing method according to  claim 44 , wherein the dicarboxylic acid has a nitrogen containing functional group.  
   
   
       46 . The polishing method according to  claim 44 , wherein the dicarboxylic acid is iminodiacetic acid.  
   
   
       47 . The polishing method according to  claim 46 , wherein the dicarboxylic acid is iminodiacetic acid.  
   
   
       48 . The polishing method according to  claim 39 , wherein the metal film comprises copper, a copper alloy or a copper compound having copper as its principal component.  
   
   
       49 . The polishing method according to  claim 39 , wherein the metal film comprises aluminum, an aluminum alloy or an aluminum compound having aluminum as its principal component.  
   
   
       50 . The polishing method according to  claim 39 , wherein the metal film comprises tungsten, a tungsten alloy or a tungsten compound having tungsten as its principal component.  
   
   
       51 . The polishing method according to  claim 50 , wherein the tungsten compound is a tungsten nitride., tantalum, tantalum nitride, silicon doped tantalum nitride, titanium nitride and silicon doped titanium nitride  
   
   
       52 . The polishing method according to  claim 39 , wherein the metal film is selected from the group consisting of titanium, a titanium alloy, or a titanium compound having titanium as its principal component.  
   
   
       53 . The polishing method according to  claim 52 , wherein the titanium compound is selected from the group consisting of titanium nitride and silicon doped titanium nitride.  
   
   
       54 . The polishing method according to  claim 39 , wherein the metal film is selected tantalum, a tantalum alloy or a tantalum compound having tantalum as its principal component.  
   
   
       55 . The polishing method according to  claim 54 , wherein the tantalum compound is selected from the group consisting of tantalum nitride and silicon doped tantalum nitride.  
   
   
       56 . The polishing method according to  claim 39 , wherein said formulation, further comprises an activating agent.  
   
   
       57 . The polishing method according to  claim 56 , wherein the activating agent is selected from the group consisting of inorganic and organic acids.  
   
   
       58 . The polishing method according to  claim 57 , wherein the inorganic acid is selected from the group consisting of phosphoric acid, fluoroboric acid, and iodic acid.  
   
   
       59 . The polishing method according to  claim 57 , wherein the organic acid is selected from the group consisting of citric acid, malic acid,  
   
   
       60 . The polishing method according to  claim 39 , further comprising a pH modifier in such amounts to modify the pH to a region of about 0.1 to 6.9, wherein said pH modifier is selected from the group consisting of: potassium hydroxide, sodium hydroxide, ammonium hydroxide, tetramethylammonium hydroxide, or quaternary ammonium hydroxide.  
   
   
       61 . The polishing method according to  claim 39 , wherein said formulation further comprises a cleaning agent.  
   
   
       62 . The polishing method according to  claim 61 , wherein the cleaning agent is a carboxylic acid.  
   
   
       63 . The polishing method according to  claim 61 , wherein the cleaning agent is selected from the group consisting of glycine, oxalic acid, malonic acid, succinic acid, citric acid and nitrilotriacetic acid.  
   
   
       64 . The polishing method according to  claim 61 , wherein the cleaning agent is a dicarboxylic acid.  
   
   
       65 . The polishing method according to  claim 64 , wherein the dicarboxylic acid has a nitrogen containing functional group.  
   
   
       66 . The polishing method according to  claim 65 , wherein the dicarboxylic acid is iminodiacetic acid.  
   
   
       67 . The polishing method according to  claim 39 , wherein said formulation further comprises an activating agent and a cleaning agent.  
   
   
       68 . The polishing method according to  claim 67 , wherein said formulation comprises:  
     
       
         
               
               
               
               
             
                   
                   
               
                   
                   
               
                   
                 a 
                 Oxidizer 
                 0.1 to 20% by weight 
               
                   
                 b. 
                 Corrosion inhibitor 
                   0 to 5% by weight 
               
                   
                 c. 
                 Activating agent 
                   0 to 5% by weight 
               
                   
                 d. 
                 Cleaning agent 
                   0 to 5% by weight 
               
                   
                   
               
                   
                   
               
           
              
              
             
             
              
              
              
              
              
              
             
          
         
       
     
   
   
       69 . The polishing method according to  claim 68 , further comprising a pH modifier in such amounts to modify the pH to a region of about 0.1 to 6.9, wherein said pH modifier is selected from the group consisting of: potassium hydroxide, sodium hydroxide, ammonium hydroxide, tetramethylammonium hydroxide, or quaternary ammonium hydroxide.  
   
   
       70 . The polishing method according to  claim 68 , wherein the cleaning agent is an inorganic acid.  
   
   
       71 . The polishing method according to  claim 68 , wherein the corrosion inhibitor is iminodiacetic acid.  
   
   
       72 . The polishing method according to  claim 39 , wherein the formulation comprises:  
     
       
         
               
               
               
               
             
                   
                   
               
                   
                   
               
                   
                 a. 
                 HIO 3   
                   4% by weight 
               
                   
                 b. 
                 IDA 
                  0.2% by weight 
               
                   
                 C. 
                 H 3 PO 4   
                 0.75% by weight 
               
                   
                 d. 
                 KOH 
                 1.73% by weight 
               
                   
                 e. 
                 Water 
                 balance 
               
                   
                   
               
                   
                   
               
           
              
              
             
             
              
              
              
              
              
              
              
             
          
         
       
     
   
   
       73 . The polishing method according to  claim 72 , wherein the pH of the formulation is in the range of from about 0.1 to 6.9.  
   
   
       74 . The abrasive free polishing formulation according to  claim 72 , wherein the pH of the formulation is about 3.5.  
   
   
       75 . The polishing method according to  claim 68 , wherein the oxidizing agent is selected from the group consisting of: hydrogen peroxide, potassium iodate, ferric nitrate, ammonium chlorite, ammonium chlorate, ammonium iodate, ammonium perborate, ammonium perchlorate, ammonium periodate ammonium persulfate, tetramethylammonium chlorite, tetramethylammonium chlorate, tetramethylammonium iodate, tetramethylammonium perborate, tetramethylammonium perchlorate, tetramethylammonium periodate, tetramethylammonium persulfate, urea hydrogen peroxide, 4-methylmorpholine N-oxide (C 5 H 11 NO 2 ) and pyridine N-oxide (C 5 H 5 NO).