| abstract |
Object is to provide an etching solution which generates less foam and can etch copper or copper alloy at high selectivity when used in a step of etching copper or copper alloy in an electronic substrate having both of copper or copper alloy and nickel. n The etching solution to be used in a step of selectively etching copper or copper alloy in an electronic substrate having both of copper or copper alloy and nickel has, as essential components thereof, (A) a linear alkanolamine, (B) a chelating agent having an acid group in the molecule thereof, and (C) hydrogen peroxide. |