Patent ID: 7056648

Claim:
A process for etching copper and copper alloys which comprises: a) contacting an exposed copper or copper alloy surface with an aqueous etching composition that comprises at least one peroxide compound selected from the group consisting of hydrogen peroxide, a peroxy carboxylate, perborate, and percarbonate, and mixtures thereof, a mixture comprising at least one weak complexant for the copper or copper alloy having a cumulative stability constant with copper of ≦10 14 selected from the group consisting of ammonia and an amine and at least one strong complexant for the copper or copper alloy having a cumulative stability constant with copper of ≧10 15 selected from the group consisting of an aminocarboxylate and an aminophosphonate, and water and further comprising a non-oxidizing acid or salt thereof or a base and has a pH of about 6 to about 12 so as to form an oxidizable etch controlling layer of a copper compound, and to remove the copper or copper alloy; and b) then contacting the structure with a non-oxidizing composition for removing the oxidizable etch controlling layer.