| abstract |
PROBLEM TO BE SOLVED: To provide an etching solution in which silicon nitride is highly selectively etched in a step of removing silicon nitride from an electronic substrate having a silicon dioxide layer and a silicon nitride layer at the same time, and no precipitate is generated after etching. The purpose is to provide. An etching solution for silicon nitride is used, which is characterized by containing a quaternary alkyl ammonium salt having a specific chemical structural formula, a basic compound, and an inorganic acid and / or an organic acid as essential components. [Selection figure] None |