Etching method

Abstract

In one embodiment, the present invention provides an etching method that can suppress the increase in etching rate caused by the increase in water content in the etching solution. In one embodiment, the present invention relates to an etching method for etching a molybdenum-containing layer, and includes the following steps 1 and 2: Step 1: Contacting an etching solution containing nitric acid and phosphoric acid with the molybdenum-containing layer to be etched; Step 2: Adding an acid anhydride to the etching solution after step 1.