US Patent 7976723 Method for kinetically controlled etching of copper

An etching composition, particularly for kinetically controlled etching of copper and copper alloy surfaces; a process for etching copper and copper alloys, particularly for etching at high rates to provide uniform and smooth, isotropic surfaces; an etched copper or copper alloy surface obtained by the process; and a process for generating copper or copper alloy electrical interconnects or contact pads. The etching composition and etching processes provide a smooth, isotropic fast etch of copper and copper alloys for semiconductor fabrication and packaging.