US Patent 7473380 Etching liquid

An etching liquid contains iodine, an iodine compound and alcohol as solute, and solvent such as water. The etching liquid etches a gold or gold alloy layer formed on the surface of a substrate for a semiconductor device or a liquid crystal device evenly. A plurality of gold or gold alloy columns is formed on the layer. The columns are etched scarcely by the etching liquid. The etching liquid etches the gold or gold alloy layer existing between the columns evenly. The etching liquid may further contain a surfactant.