| 摘要 |
PURPOSE: To obtain a method of treating the copper circuit of an internal layer use wiring board, which does not generate a striped and spotted color shading and improves the visual appearance of the copper circuit, by a method wherein an oxidation treatment is performed on the copper circuit of the internal layer use wiring board to form a copper oxide film and thereafter, the film is dipped in an acid solution, which contains a dilute sulfuric acid and chelate and contains copper ions of a specified concentration. CONSTITUTION: An oxidation treatment is performed on a copper circuit of an internal layer use wiring board to form a copper oxide film and thereafter, the copper oxide film is dipped in an acid solution, which containts a dilute sulfuric acid and a chelate and contains copper ions of a concentration in a range of 0.8 to 12g/l. Here, the pH value of the acid solution is 30.0 to 4.0 and after being dipped in this acid solution, the copper oxide film is dipped in the chelate-containing acid solution in a range of pH value of 4.5 to 5.5 and is cleaned. Moreover, as a pretreatment for performing the oxidation treatment on the copper circuit of the internal layer use wiring board, a first soft etching is performed on the copper circuit with a ferric chloride-containing aqueous solution and thereafter, the copper oxide film is treated by a second soft etching with either of an aqueous solution containing sulfuric acid and ammonium sulfate and an aqueous solution containing sulfuric acid and hydrogen peroxide. |
