Method for preparing polishing slurry

Abstract

The method for manufacturing polishing slurries is useful for polishing electronic substrates. The method includes preparing an aqueous intermediate dispersion, the aqueous intermediate dispersion containing solid particles; and introducing an azole compound into the aqueous intermediate dispersion to prevent biological activity and to form a stable intermediate dispersion. Then storing the stable intermediate dispersion; and introducing additional components to the stable intermediate dispersion to form a final polishing slurry.

1 . A method for manufacturing polishing slurries useful for polishing patterned integrated circuit substrates comprising the steps of: 
 preparing an aqueous intermediate dispersion, the aqueous intermediate dispersion containing solid particles and having an acidic pH;    introducing an azole compound into the aqueous intermediate dispersion to prevent biological activity and to form a stable intermediate dispersion;    storing the stable intermediate dispersion for at least one day; and    introducing additional components to the stable intermediate dispersion to form a final polishing slurry, the final polishing slurry having an acidic pH.    
   
   
       2 . The method of  claim 1  wherein the azole compound is selected from at least one of the group of 1,2,4-triazole, 3-methyl-1,2,4-triazole, 3,5-dimethyl-1,2,4-triazole, 1-amino-1,2,4-triazole, 3-amino-1,2,4-triazole, 5-amino-3-methyl-1,2,4-triazole, 3-isopropyl-1,2,4-triazole, 1,2,3-triazole, 1-methyl-1,2,3-triazole, 1-amino-1,2,3-triazole, 1-amino-5-methyl-1,2,3-triazole, 4,5-dimethyl-1,2,3-triazole, 1-amino-5-n-propyl-1,2,3-triazole, 1-(β-aminoethyl)-1,2,3-triazole, 1-methyltetrazole, 2-methyltetrazole, 5-amino-1H-tetrazole, 5-amino-1-methyltetrazole, 1-(β-aminoethyl)tetrazole, a substituted triazole and tetrazole compound having an electron-donating substituent.  
   
   
       3 . The method of  claim 1  including the step of adding additional azole compound with the additional components to maintain concentration of the azole compound above a level that prevents biological activity.  
   
   
       4 . The method of  claim 1  including the additional step of adding an oxidizer to the final polishing slurry.  
   
   
       5 . A method for manufacturing polishing slurries useful for polishing patterned integrated substrates, the patterned dielectric substrates having nonferrous interconnects, comprising the steps of: 
 preparing an aqueous intermediate dispersion, the aqueous intermediate dispersion containing solid particles and having a pH less than 5;    introducing at least 0.1 weight percent benzotriazole into the aqueous intermediate dispersion to prevent biological activity and to form a stable intermediate dispersion;    storing the stable intermediate dispersion at least one week; and    introducing additional components to the stable intermediate dispersion to form a final polishing slurry, the final polishing slurry having a pH less than 5.    
   
   
       6 . The method of  claim 5  including the step of adding additional benzotriazole with the additional components to maintain concentration of the benzotriazole above at least 0.2 weight percent to prevent biological activity.  
   
   
       7 . The method of  claim 5  including the additional step of adding an oxidizer to the final polishing slurry.  
   
   
       8 . The method of  claim 5  wherein the nonferrous interconnects are copper and including the additional step of polishing the patterned wafer.  
   
   
       9 . The method of  claim 8  wherein the benzotriazole decreases removal rate of the copper nonferrous interconnects.  
   
   
       10 . The method of  claim 5  wherein the pH is less than 5 and the solid particles include silica.