| abstract |
A wet etching solution includes hydrogen fluoride in an amount of about 0.1% to about 3% by weight of the etching solution, an inorganic acid in an amount of about 10% to about 40% by weight of the etching solution, the inorganic acid being one or more of nitric acid, sulfuric acid, and/or hydrochloric acid, a nonionic surfactant in an amount of about 0.0001% to about 5% by weight of the etching solution, the nonionic surfactant including one or ore of alkylphenol ethoxylate and/or ammonium lauryl sulfate, and water. |