Copper etchant

Abstract

A problem is to provide a copper etchant capable of stably maintaining smoothness after etching. As means for solving the problem, the etchant contains hydrogen peroxide, sulfuric acid, an aromatic compound, and a chlorine ion, in which the aromatic compound has a structure in which a hydroxyl group and/or a carboxy group is bonded to a benzene ring.

1 . A copper etchant comprising hydrogen peroxide, sulfuric acid, an aromatic compound, and a chlorine ion,
 wherein the aromatic compound has a structure in which a hydroxyl group and/or a carboxy group is bonded to a benzene ring.   
     
     
         2 . The copper etchant according to  claim 1 , wherein the chlorine ion is contained in an amount of 0.000020 mass % or more and 0.02 mass % or less. 
     
     
         3 . The copper etchant according to  claim 1 , wherein the aromatic compound is one or more selected from the group consisting of phenols, a benzoic acid compound, 2-hydroxybenzoic acid, 5-sulfosalicylic acid, methyl salicylate, sodium salicylate, isoamyl salicylate, and acetylsalicylic acid. 
     
     
         4 . The copper etchant according to  claim 1 , further comprising triazoles. 
     
     
         5 . The copper etchant according to  claim 4 , wherein the triazoles are one or more selected from the group consisting of 1,2,4-triazole, 1,2,3-triazole, 3-amino-5-mercapto-1,2,4-triazole, 3,5-diamino-1,2,4-triazole, 3,5-dimethyl-1,2,4-triazole, 3-mercapto-1,2,4-triazole, 4-amino-1,2,4-triazole, 3-amino-1,2,4-triazole, 4-amino-3-mercapto-4H-1,2,4-triazole, and 3-amino-5-methylthio-1H-1,2,4-triazole.