Etching composition

The invention discloses an etching composition. Specifically, the invention relates to an etching composition for selectively etching a titanium nitride hard photomask, which comprises an alkaline compound, a chelating agent, a corrosion inhibitor and a solvent. The etching composition provided by the invention has excellent etching selectivity, can quickly remove titanium nitride (TiN) and dry etching residues, does not damage a lowk layer and a metal conductor layer, still has certain oxidation capacity, etching selectivity, pH value and other characteristics after being repeatedly used, andis suitable for being used in a recycling process. 本发明公开了蚀刻组合物。具体地，本发明涉及一种用于选择性蚀刻氮化钛硬光罩的蚀刻组合物，包括碱性化合物、螯合剂、腐蚀抑制剂以及溶剂。本发明的蚀刻组合物具有优异的蚀刻选择性，能快速清除氮化钛(TiN)及干式蚀刻残留物，不会损及low-k层及金属导体层，且重复使用蚀刻组合物仍保有一定的氧化能力、蚀刻选择性及pH值等特性，适合用于再循环式过程中。