AN ETCHING SOLUTION COMPOSITION FOR METAL LAYER CONTAINING COPPER/METAL OXIDE LAYER CONTAINING GALLIUM

摘要

PURPOSE: An etching solution composition is provided to prevent the formation of undercut in a gallium-containing metal oxide film and to prevent damage to equipment. CONSTITUTION: An etching solution composition for a copper metal film and a gallium-containing metal oxide film comprises 5-20 wt% of persulfate salt, 1-15 wt% of inorganic acid, 0.1-5 wt% of phosphate, 0.3-5 wt% of ring type amine compounds, and residual water. The persulfate salt is one or more kinds selected from a group comprising ammonium persulfate, sodium persulfate, and potassium persulfate. A method for manufacturing a thin film transistor comprises a process for forming patterns by etching a copper metal film and a gallium-containing metal oxide film at a time.