Composition useful for removal of post-etch photoresist and bottom anti-reflection coatings

Abstract

An aqueous-based composition and process for removing hardened photoresist and/or bottom anti-reflective coating (BARC) material from a substrate having same thereon. The aqueous-based composition includes at least one chaotropic solute, at least one alkaline base, and deionized water. The composition achieves high-efficiency removal of hardened photoresist and/or BARC material in the manufacture of integrated circuitry without adverse effect to metal species on the substrate, such as copper, and without damage to low-k dielectric materials employed in the semiconductor architecture.

1 . An aqueous-based removal composition, said composition comprising at least one chaotropic solute and at least one alkaline salt in an aqueous medium, wherein the removal composition is useful for removing photoresist and/or BARC materials from a substrate having said material(s) thereon.  
   
   
       2 . The composition of  claim 1 , comprising the following components based on the total weight of the composition: 
 60.0% wt-98.0% wt. deionized water    1.0% wt-30.0% wt chaotropic solute; and    1.0% wt-10.0% wt alkaline salt,    wherein the total of the weight percentages of such components of the composition does not exceed 100% weight.    
   
   
       3 . The composition of  claim 1 , wherein the at least one chaotropic solute comprises a chaotropic species selected from the group consisting of: urea; guanidinium chloride; 2-, 3-, and 4-aminobenzoic acid; 2-, 3-, and 4-nitrobenzoic acid; 2-, 3-, and 4-anisic acid; 2-, 3-, and 4-fluoro-, chloro-, bromo-, and iodo-benzoic acid; 2-, 3-, and 4-methylthio-benzoic acid; 2,4-diamino-6-methyl-1,3,5-triazine; aniline; 2-, 3-, and 4-methylthio-aniline; 2-, 3-, and 4-anisidine; 1,2-, 1,3-, and 1,4-phenylenediamine; 1,3,5-triazine; melamine; acetoguanamine; 2,4-diamino-6-phenyl-1,3,5-triazine; 2-chloro-4,6-diamino-1,3,5-triazine; 2,4,6-trimethoxy-1,3,5-triazine; 2,4,6-trimethoxy-1,3,5-triazine; 2,4-diamino-1,3,5-triazine; 2-amino-1,3,5-triazine; 2-amino-4-ethoxy-6-methylamino)-1,3,5-triazine; 2-methoxy-4-methyl-4-(methylamino)-1,3,5-triazine; 1,2,4-triazole; imidazole; 2-mercaptoimidazole; 2-nercaptobenzimidazole; chaotropic anions selected from the group consisting of chloride salts, bromide salts, iodide salts, nitrate salts, thiocyanide salts, chlorate salts, and benzoate salts; and combinations thereof.  
   
   
       4 . The composition of  claim 3 , wherein the cation associated with the chaotropic anion comprises (NR 1 R 2 R 3 R 4 ) + , wherein R 1 , R 2 , R 3  and R 4  may be the same as or different from one another and each is independently selected from the group consisting of hydrogen and C 1 -C 6  alkyl groups.  
   
   
       5 . The composition of  claim 1 , wherein the at least one chaotropic solute comprises a chaotropic anion having an atomic or molecular radius of greater than or equal to 1.6 Å.  
   
   
       6 . The composition of  claim 1 , wherein the at least one chaotropic solute comprises urea.  
   
   
       7 . The composition of  claim 1 , wherein the at least one alkaline salt comprises (NR 1 R 2 R 3 R 4 )OH, wherein R 1 , R 2 , R 3  and R 4  may be the same as or different from one another and each is independently selected from the group consisting of hydrogen and C 1 -C 6  alkyl groups.  
   
   
       8 . The composition of  claim 1 , having a pH greater than about 13.  
   
   
       9 . The composition of  claim 1 , selected from the group consisting of Formulations A-G, wherein all percentages are by weight based on the total weight of the formulation: 
 Formulation A    2.5 wt. % tetramethylammonium hydroxide;    20.0 wt. % urea;    77.5 wt. % deionized water;    Formulation B    1.5 wt. % tetramethylammonium hydroxide;    1.6 wt % 2,4-diamino-6-methyl-1,3,5-triazine;    20.0 wt. % urea;    76.9 wt % deionized water,    Formulation C    2.0 wt. % tetrwnethylammonium hydroxide;    1.0 wt. % 2,4-diamino-6-methyl-1,3,5-triazine;    1.0 wt. % 4-aminobenzoic acid;    96.0 wt. % deionized water,    Formulation D    2.0 wt % tetramethylammonium hydroxide;    2.4 wt. % tetramethylammonium nitrate;    95.6 wt. % deionized water,    Formulation E    5.0 wt. % tetramethylammonium hydroxide;    9.0 wt. % tetramethylammonium nitrate;    10.0 wt. % butyl carbitol;    10.0 wt. % sulfolane-w;    66.0 wt. % deionized water.    Formulation F    from about 1.0 wt % to about 5.0 wt. % tetramethylammonium hydroxide    from about 1.0 wt. % to about 20.0 wt. % of 2-, 3-, or 4-nitrobenzoic acid tetramethylammonium salt    remainder deionized water    and    Formulation G    from about 1.0 wt. % to about 5.0 wt. % tetramethylammonium hydroxide    from about 1.0 wt. % to about 20.0 wt. % of ortho-, meta-, or para-phenylenediamine remainder deionized water.    
   
   
       10 . A method of removing photoresist and/or BARC material from a substrate having said material thereon, said method comprising contacting the substrate with an aqueous-based removal composition for sufficient time to at least partially remove said material from the substrate, wherein the aqueous-based removal composition comprises at least one chaotropic solute and at least one alkaline salt in an aqueous medium.  
   
   
       11 . The method of  claim 10 , wherein the aqueous-based removal composition comprises the following components, based on the total weight of the composition: 
 60.0% wt.-98.0% wt. deionized water    1.0% wt.-30.0% wt. chaotropic solute; and    1.0% wt.-10.0% wt. alkaline salt,    wherein the total of the weight percentages of such components of the composition does not exceed 100% weight.    
   
   
       12 . The method of  claim 10 , wherein the substrate comprises a semiconductor device structure.  
   
   
       13 . The method of  claim 10 , wherein the material comprises a layer selected from the group consisting of: photoresist hardened by plasma etching; photoresist hardened by ion implantation; and BARC.  
   
   
       14 . The method of  claim 10 , wherein said contacting is carried out for a time of from about 1 minute to about 60 minutes.  
   
   
       15 . The method of  claim 10 , wherein said contacting is carried out at temperature in a range of from about 40° C. to about 80° C.  
   
   
       16 . The method of  claim 10 , wherein the at least one chaotropic solute comprises a chaotropic species selected from the group consisting of: urea; guanidinium chloride; 2-, 3-, and 4-aminobenzoic acid; 2-, 3-, and 4-nitrobenzoic acid; 2-, 3-, and 4-anisic acid; 2-, 3-, and 4-fluoro-, chloro-, bromo-, and iodo-benzoic acid; 2-, 3-, and 4-methylthio-benzoic acid; 2,4-diamino-4-methyl-1,3,5-triazine; aniline; 2-, 3-, and 4-methylthio-aniline; 2-, 3-, and 4-anisidine; 1,2-, 1,3-, and 1,4-phenylenediamine; 1,3,5-triazine; melamine; acetoguanamine; 2,4-diamino-6-phenyl-1,3,5-triazine; 2-chloro-4,6-diamino-1,3,5-triazine; 2,4,6-trimethoxy-1,3,5-triazine; 2,4,6-trimethoxy-1,3,5-triazine; 2,4-diamino-1,3,5-triazine; 2-amino-1,3,5-triazine; 2-amino-4-ethoxy-6-methylamino)-1,3,5-triazine; 2-methoxy-4-methyl-6-methylamino)-1,3,5-triazine; 1,2,4-triazole; imidazole; 2-mercaptoimidazole; 2-mercaptobenzimidazole; chaotropic anions selected from the group consisting of chloride salts, bromide salts, iodide salts, nitrate salts, thiocyanide salts, chlorate salts, and benzoate salts; and combinations thereof.  
   
   
       17 . The method of  claim 16 , wherein the cation associated with the chaotropic anion comprises (NR 1 R 2 R 3 R 4 ) + , wherein R 1 , R 2 , R 3  and R 4  may be the same as or different from one another and each is independently selected from the group consisting of hydrogen and C 1 -C 6  alkyl groups.  
   
   
       18 . The method of  claim 10 , wherein the at least one alkaline salt comprises (NR 1 R 2 R 3 R 4 )OH, wherein R 1 , R 2 , R 3  and R 4  may be the same as or different from one another and each is independently selected from the group consisting of hydrogen and C 1 -C 6  alkyl groups.  
   
   
       19 . The method of  claim 10 , wherein the aqueous-based removal composition is selected from the group consisting of Formulations A-G, wherein all percentages are by weight, based on the total weight of the formulation: 
 Formulation A    2.5 wt. % tetramethylammonium hydroxide;    20.0 wt. % urea;    77.5 wt % deionized water,    Formulation B    1.5 wt. % tetramethylammonium hydroxide;    1.6 wt. % 2,4-diamino-4-methyl-1,3,5-triazine;    20.0 wt. % urea;    76.9 wt. % deionized water;    Formulation C    2.0 wt. % tetramethylammonium hydroxide;    1.0 wt. % 2,4-diamino-6-methyl-1,3,5-triazine;    1.0 wt. % 4-aminobenzoic acid;    96.0 wt. % deionized water;    Formulation D    2.0 wt. % tetramethylammonium hydroxide;    2.4 wt. % tetramethylammonium nitrate;    95.6 wt. % deionized water;    Formulation E    5.0 wt. % tetramethylammonium hydroxide;    9.0 wt. % tetramethylammonium nitrate;    10.0 wt % butyl carbitol;    10.0 wt % sulfolane-w;    66.0 wt. % deionized water    Formulation F    from about 1.0 wt % to about 5.0 wt. % tetramethylammonium hydroxide    from about 1.0 wt. % to about 20.0 wt. % of 2-, 3-, or 4-nitrobenzoic acid tetramethylammonium salt    remainder deionized water    and    Formulation G    from about 1.0 wt. % to about 5.0 wt. % tetramethylammonium hydroxide    from about 1.0 wt. % to about 20.0 wt. % of ortho-, meta-, or para-phenylenediamine remainder deionized water    
   
   
       20 . The method of  claim 10 , further comprising rinsing the substrate with deionized water following contact with the aqueous-based removal composition.  
   
   
       21 . The composition of  claim 1 , wherein both the at least one chaotropic solute and the at least one alkaline salt are metal-ion free.  
   
   
       22 . The method of  claim 10 , wherein both the at least one chaotropic solute and the at least one alkaline salt are metal-ion free.  
   
   
       23 . The composition of  claim 1 , further comprising photoresist material.  
   
   
       24 . The composition of  claim 1 , further comprising BARC material.  
   
   
       25 . The method of  claim 10 , wherein the aqueous-based removal composition further comprises photoresist material.  
   
   
       26 . The method of  claim 10 , wherein the aqueous-based removal composition further comprises BARC material.