Etchant composition and methods of fabricating metal wiring and thin film transistor substrate using the same

A method of forming a metal wiring, the method comprising:

• providing a metal layer comprising copper;
• forming a photoresist layer pattern on the metal layer, and etching a portion of the metal layer with an etchant composition utilizing the photoresist layer pattern as a mask;
• and
• removing the photoresist layer pattern,
• wherein the etchant composition comprises 0.5 wt % to 20 wt % of a persulfate, 0.01 wt % to 1 wt % of a fluorine compound, 1 wt % to 10 wt % of an inorganic acid, 0.01 wt % to 2 wt % of an azole-based compound, 0.1 wt % to 5 wt % of a chlorine compound, 0.05 wt % to 3 wt % of a copper salt, 0.01 wt % to 5 wt % of an antioxidant or a salt thereof, based on a total weight of the etchant composition, and water in an amount sufficient for the total weight of the etchant composition to be equal to 100 wt %.

A method of forming a thin film transistor substrate, the method comprising:

• forming a gate line and a gate electrode coupled to the gate line on a substrate;
• forming a data line insulatively crossing the gate line, a source electrode coupled to the data line, and a drain electrode spaced apart from the source electrode;
• and
• forming a pixel electrode coupled to the drain electrode,
• wherein the forming of the data line, the source electrode, and the drain electrode comprises:
• providing a metal layer comprising copper;
• forming a photoresist layer pattern on the metal layer, and etching a portion of the metal layer with an etchant composition utilizing the photoresist layer pattern as a mask;
• and
• removing the photoresist layer pattern,
• wherein the etchant composition comprises 0.5 wt % to 20 wt % of a persulfate, 0.01 wt % to 1 wt % of a fluorine compound, 1 wt % to 10 wt % of an inorganic acid, 0.01 wt % to 2 wt % of an azole-based compound, 0.1 wt % to 5 wt % of a chlorine compound, 0.05 wt % to 3 wt % of a copper salt, 0.01 wt % to 5 wt % of an antioxidant or a salt thereof, based on a total weight of the etchant composition, and water in an amount sufficient for the total weight of the etchant composition to be equal to 100 wt %.