ETCHANTS AND METHODS OF FABRICATING METAL WIRING AND THIN FILM TRANSISTOR SUBSTRATE USING THE SAME

1 . An etchant comprising:

a persulfate contained in an amount of about 0.5 weight % to about 20 weight %, with respect to a total weight of the etchant;

a fluoride contained in an amount of about 0.01 weight % to about 2 weight %, with respect to the total weight of the etchant;

an inorganic acid contained in an amount of about 1 weight % to about 10 weight %, with respect to the total weight of the etchant;

a cyclic amine contained in an amount of about 0.5 weight % to about 5 weight %, with respect to the total weight of the etchant;

a sulfonic acid contained in an amount of about 0.1 weight % to about 10.0 weight %, with respect to the total weight of the etchant; and

at least one of an organic acid or a salt thereof contained in an amount of about 0.1 weight % to about 10 weight %, with respect to the total weight of the etchant.

2 . The etchant of claim 1 , wherein the persulfate is at least one of K 2 S 2 O 8 , Na 2 S 2 O 8 , or (NH 4 ) 2 S 2 O 8 .

3 . The etchant of claim 2 , wherein the fluoride is at least one of an ammonium fluoride, a sodium fluoride, a potassium fluoride, an ammonium bifluoride, a sodium bifluoride, or a potassium bifluoride.

4 . The etchant of claim 2 , wherein the inorganic acid is at least one of a nitric acid, a sulfuric acid, a phosphoric acid, or a perchloric acid.

5 . The etchant of claim 2 , wherein the cyclic amine is at least one of aminotetrazole, imidazole, indole, purine, pyrazole, pyridine, pyrimidine, pyrrole, pyrrolidine, or pyrroline.

6 . The etchant of claim 2 , wherein the sulfonic acid is a p-toluene sulfonic acid or methane sulfonic acid.

7 . The etchant of claim 2 , wherein the organic acid is a carboxylic acid, a dicarboxylic acid, a tricarboxylic acid, or a tetracarboxylic acid.

8 . The etchant of claim 7 , wherein the organic acid is at least one of an acetic acid, a butanoic acid, a citric acid, a formic acid, a gluconic acid, a glycolic acid, a malonic acid, an oxalic acid, a pentanoic acid, a sulfobenzoic acid, a sulfosuccinic acid, a sulfophthalic acid, a salicylic acid, a sulfosalicilic acid, a benzoic acid, a lactic acid, a glyceric acid, a succinic acid, a malic acid, a tartaric acid, an isocitric acid, a propenoic acid, an imminodiacetic acid, or an ethylenediaminetetraacetic acid.

9 . The etchant of claim 1 , further comprising an amount of water such that the total weight of the etchant is 100 weight %.

10 . The etchant of claim 1 , wherein the etchant etches a multilayer including of copper and titanium.

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

forming a metal layer comprising copper and titanium;

forming a photoresist layer pattern on the metal layer;

etching a portion of the metal layer with an etchant by using the photoresist layer pattern as a mask; and

removing the photoresist layer pattern,

wherein the etchant comprises:

a persulfate contained in an amount of about 0.5 weight % to about 20 weight %, with respect to a total weight of the etchant;

a fluoride contained in an amount of about 0.01 weight % to about 2 weight %, with respect to the total weight of the etchant;

an inorganic acid contained in an amount of about 1 weight % to about 10 weight %, with respect to the total weight of the etchant;

a cyclic amine contained in an amount of about 0.5 weight % to about 5 weight %, with respect to the total weight of the etchant;

a sulfonic acid contained in an amount of about 0.1 weight % to about 10.0 weight %, with respect to the total weight of the etchant; and

at least one of an organic acid or a salt thereof of about 0.1 weight % to about 10 weight %, with respect to the total weight of the etchant.

12 . The method of claim 11 , wherein the metal layer comprises a first metal layer including the titanium, and a second metal layer including the copper on the first metal layer.

13 . The method of claim 11 , wherein the persulfate is at least one of K 2 S 2 O 8 , Na 2 S 2 O 8 , or (NH 4 ) 2 S 2 O 8 .

14 . The method of claim 13 , wherein the fluoride is at least one of an ammonium fluoride, a sodium fluoride, a potassium fluoride, an ammonium bifluoride, a sodium bifluoride, or a potassium bifluoride.

15 . The method of claim 13 , wherein the inorganic acid is at least one of a nitric acid, a sulfuric acid, a phosphoric acid, or a perchloric acid.

16 . The method of claim 13 , wherein the cyclic amine is at least one of aminotetrazole, imidazole, indole, purine, pyrazole, pyridine, pyrimidine, pyrrole, pyrrolidine, or pyrroline.

17 . The method of claim 13 , wherein the sulfonic acid is a p-toluene sulfonic acid or methane sulfonic acid.

18 . The method of claim 13 , wherein the organic acid is a carboxylic acid, a dicarboxylic acid, a tricarboxylic acid, or a tetracarboxylic acid.

19 . The method of claim 18 , wherein the organic acid is at least one of an acetic acid, a butanoic acid, a citric acid, a formic acid, a gluconic acid, a glycolic acid, a malonic acid, an oxalic acid, a pentanoic acid, a sulfobenzoic acid, a sulfosuccinic acid, a sulfophthalic acid, a salicylic acid, a sulfosalicilic acid, a benzoic acid, a lactic acid, a glyceric acid, a succinic acid, a malic acid, a tartaric acid, an isocitric acid, a propenoic acid, an imminodiacetic acid, or an ethylenediaminetetraacetic acid.

20 . The method of claim 11 , wherein the etchant further comprises an amount of water such that the total weight of the etchant is 100 weight %.

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

forming a gate line on a substrate, and a gate electrode connected to the gate line;

forming a data line intersecting the gate line and insulated from the gate line, a source electrode connected to the data line, and a drain electrode spaced from the source electrode; and

forming a pixel electrode connected to the drain electrode,

wherein the forming the gate line, and the gate electrode connected to the gate line comprises:

forming a metal layer comprising copper and titanium;

forming a photoresist layer pattern on the metal layer;

etching a portion of the metal layer with an etchant by using the photoresist layer pattern as a mask; and

removing the photoresist layer pattern,

wherein the etchant comprises:

a persulfate contained in an amount of about 0.5 weight % to about 20 weight %, with respect to a total weight of the etchant;

a fluoride contained in an amount of about 0.01 weight % to about 2 weight %, with respect to the total weight of the etchant;

an inorganic acid contained in an amount of about 1 weight % to about 10 weight %, with respect to the total weight of the etchant;

a cyclic amine contained in an amount of about 0.5 weight % to about 5 weight %, with respect to the total weight of the etchant;

a sulfonic acid contained in an amount of about 0.1 weight % to about 10.0 weight %, with respect to the total weight of the etchant; and

at least one of an organic acid or a salt thereof of about 0.1 weight % to about 10 weight %, with respect to the total weight of the etchant.

22 . The method of claim 21 , wherein the metal layer comprises a first metal layer including the titanium, and a second metal layer including the copper on the first metal layer.

23 . The method of claim 21 , wherein the etchant further comprises an amount of water such that the total weight of the etchant is 100 weight %.