Method for releasing resist

Abstract

In the resist stripping method of the present invention, a wiring substrate having a remaining resist layer is brought into contact with a resist stripping composition in an atmosphere containing oxygen in a proportion of 2% by volume or less. Preferably, the resist is removed after pretreating the remaining resist layer with hydrogen peroxide. A resist stripping composition comprising an amine compound, a solvent, a strong alkali, and water is preferably used in the resist stripping method of the present invention.

1 . A resist stripping method comprising a step of bringing a wiring substrate having a remaining resist layer after etching into contact with a resist stripping composition in an atmosphere containing oxygen in a proportion of 2% by volume or less.  
     
     
         2 . The resist stripping method according to  claim 1 , wherein the step of bringing the wiring substrate into contact with the resist stripping composition is performed while driving out dissolved gas from the resist stripping composition.  
     
     
         3 . The resist stripping method according to  claim 1 , wherein the step of bringing the wiring substrate into contact with the resist stripping composition is performed after deaeration of the resist stripping composition.  
     
     
         4 . The resist stripping method according to  claim 1 , wherein the remaining resist layer is subjected to a pretreatment by a contact with hydrogen peroxide before bringing the wiring substrate into contact with the resist stripping composition.  
     
     
         5 . The resist stripping method according to  claim 4 , wherein the pretreatment is performed by bringing the remaining resist layer into contact with a solution having a hydrogen peroxide concentration of 0.5% by weight or higher.  
     
     
         6 . The resist stripping method according to  claim 1 , wherein a dissolved oxygen concentration in the resist stripping composition is 3 ppm or less.  
     
     
         7 . The resist stripping method according to  claim 1 , wherein the resist stripping composition comprises an amine compound, a solvent, a strong alkali, and water.  
     
     
         8 . The resist stripping method according to  claim 7 , wherein the resist stripping composition comprises 5 to 95% by weight of the amine compound, 3 to 85% by weight of the solvent, 0.01 to 5% by weight of the strong alkali, and 1 to 25% by weight of water.  
     
     
         9 . The resist stripping method according to  claim 7 , wherein the amine compound is at least one compound selected from the group consisting of ethanolamine, 1-amino-2-propanol, N-(aminoethyl)ethanolamine, N-methylethanolamine, N-ethylethanolamine, diethanolamine, isopropanolamine, 2-(2-aminoethoxy)ethanol, ethylenediamine, propanediamine, butylenediamine, diethylenetriamine, piperazine, morpholine, triethylenetetramine, tetraethylenepentamine, and pentaethylenehexamine.  
     
     
         10 . The resist stripping method according to  claim 7 , wherein the strong alkali is at least one compound selected from the group consisting of tetramethylammonium hydroxide, choline hydroxide, tetraethylammonium hydroxide, and tetrabutylammonium hydroxide.  
     
     
         11 . The resist stripping method according to  claim 7 , wherein the solvent is at least one compound selected from the group consisting of dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monobutyl ether, and propylene glycol.  
     
     
         12 . The resist stripping method according to  claim 7 , wherein the wiring substrate has a copper layer or a copper alloy layer.  
     
     
         13 . The resist stripping method according to  claim 2 , wherein the remaining resist layer is subjected to a pretreatment by a contact with hydrogen peroxide before bringing the wiring substrate into contact with the resist stripping composition.  
     
     
         14 . The resist stripping method according to  claim 13 , wherein the pretreatment is performed by bringing the remaining resist layer into contact with a solution having a hydrogen peroxide concentration of 0.5% by weight or higher.  
     
     
         15 . The resist stripping method according to  claim 3 , wherein the remaining resist layer is subjected to a pretreatment by a contact with hydrogen peroxide before bringing the wiring substrate into contact with the resist stripping composition.  
     
     
         16 . The resist stripping method according to  claim 15 , wherein the pretreatment is performed by bringing the remaining resist layer into contact with a solution having a hydrogen peroxide concentration of 0.5% by weight or higher.  
     
     
         17 . The resist stripping method according to  claim 8 , wherein the amine compound is at least one compound selected from the group consisting of ethanolamine, 1-amino-2-propanol, N-(aminoethyl)ethanolamine, N-methylethanolamine, N-ethylethanolamine, diethanolamine, isopropanolamine, 2-(2-aminoethoxy)ethanol, ethylenediamine, propanediamine, butylenediamine, diethylenetriamine, piperazine, morpholine, triethylenetetramine, tetraethylenepentamine, and pentaethylenehexamine.  
     
     
         18 . The resist stripping method according to  claim 17 , wherein the strong alkali is at least one compound selected from the group consisting of tetramethylammonium hydroxide, choline hydroxide, tetraethylammonium hydroxide, and tetrabutylammonium hydroxide.  
     
     
         19 . The resist stripping method according to  claim 9 , wherein the strong alkali is at least one compound selected from the group consisting of tetramethylammonium hydroxide, choline hydroxide, tetraethylammonium hydroxide, and tetrabutylammonium hydroxide.  
     
     
         20 . The resist stripping method according to  claim 8 , wherein the strong alkali is at least one compound selected from the group consisting of tetramethylammonium hydroxide, choline hydroxide, tetraethylammonium hydroxide, and tetrabutylammonium hydroxide.  
     
     
         21 . The resist stripping method according to  claim 10 , wherein the solvent is at least one compound selected from the group consisting of dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monobutyl ether, and propylene glycol.  
     
     
         22 . The resist stripping method according to  claim 10 , wherein the wiring substrate has a copper layer or a copper alloy layer.