| abstract |
Disclosed is an etching solution for copper or a copper alloy, which is mainly composed of water and contains (1) 5 to 20 mass% of iron chloride (III), (2) 0.5 to 3 mass% of copper chloride (II), and (3) a compound capable of, together with copper, forming an insoluble salt in an amount of 5 to 20 mass% relative to the amount of iron chloride (III). Also disclosed is an etching method using the etching solution as a new solution. Further disclosed is a method for managing the reproduction of an etching solution, in which the management of reproduction is carried out by employing the ratio of permeability among two or more different wavelengths. |