Patent ID: 7285229
Filing Date: 2007-10-23
Classification: C23F,H05K

Abstract:
1. A method for etching at least one metal selected from nickel, chromium, nickel-chromium alloys, and palladium, comprising: bringing an etchant comprising an aqueous solution comprising hydrochloric acid, nitric acid, and a cupric ion source into contact with the metal; wherein the etchant comprising the aqueous solution comprising the hydrochloric acid, the nitric acid, and the cupric ion source is used as a second etchant, and the method further comprises bringing a first etchant into contact with the metal before bringing the second etchant into contact with the metal, the first etchant comprising an aqueous solution comprising at least the following components A to C: A. hydrochloric acid; B. at least one compound selected from the following (a) to (c): (a) compounds with 7 or less carbon atoms, containing a sulfur atom and at least one group selected from an amino group, an imino group, a carboxyl group, a carbonyl group, and a hydroxyl group; (b) thiazole; and (c) thiazole compounds and C. a surfactant.