ETCHING SOLUTION AND ETCHING CONCENTRATE FOR MULTILAYER FILM, AND ETCHING METHOD

摘要

Provided is an etching solution which is for etching a multilayer film composed of a copper layer having a large film thickness and a titanium base layer, and can be used even when the concentration of metal ions is 8,000 ppm or higher. The etching solution includes (a) hydrogen peroxide, (b) a fluorine ion supply source, (c) azoles, (d) a hydrogen peroxide stabilizer, (e) an organic acid, (f) amines, and (g) water, wherein a methane sulfonic acid and one organic acid among lactic acid, succinic acid, glutaric acid, and malonic acid are used as the organic acid, or lactic acid is used alone as the organic acid.