Etchant for etching metal wiring layers and method for forming thin film transistor by using the same
View Patent ↗The present invention discloses an etchant for etching at least two different metal layers, the etchant comprising hydrogen peroxide (H 2 O 2 ) and one of carboxylic acid, carboxylate salt, and acetyl group (CH 3 CO—). The present invention also discloses a method of fabricating a metal wiring on a substrate, the method comprising forming a first metal layer on a substrate, forming a second metal layer on the first metal layer, and simultaneously etching the first metal layer and the second metal layer with an etchant comprising hydrogen peroxide (H 2 O 2 ) and one of carboxylic acid, carboxylate salt, and acetyl group (CH 3 CO—)
1. A method of fabricating a metal wiring on a substrate, comprising:
forming a first metal layer on a substrate;
forming a second metal layer on the first metal layer; and
simultaneously etching the first metal layer and the second metal layer with an etchant comprising hydrogen peroxide (H 2 O 2 ) and one of acetic acid (CH 3 COOH), citric acid (C 6 H 8 O 7 ), oxalic acid (C 2 H 2 O 4 ), and tartaric acid (C 4 H 6 O 6 ).
2. A method of fabricating a metal wiring on a substrate, comprising:
forming a first metal layer on a substrate;
forming a second metal layer on the first metal layer; and
simultaneously etching the first metal layer and the second metal layer with an etchant comprising hydrogen peroxide (H 2 O 2 ) and one of ammonium acetate (CH 3 COONH 4 ), sodium acetate (CH 3 COONa), and potassium acetate (CH 3 COOK).
3. A method of fabricating a metal wiring on a substrate, comprising:
forming a first metal layer on a substrate;
forming a second metal layer on the first metal layer; and
simultaneously etching the first metal layer and the second metal layer with an etchant comprising hydrogen peroxide (H 2 O 2 ) and one of pivalic acid ((CH 3 ) 3 C 2 OOH), ammonium pivalate ((CH 3 ) 3 C 2 OONH 4 ), sodium pivalate ((CH 3 ) 3 C 2 OONa), and potassium pivalate ((CH 3 ) 3 C 2 OOK).
4. The method according to claim 1 , wherein one of the acetic acid (CH 3 COOH), the citric acid C 6 H 8 O 7 ), the oxalic acid (C 2 H 2 O 4 ), and the tartaric acid (C 4 H 6 O 6 ) has a concentration of about 0.5 wt % or more, and the hydrogen peroxide (H 2 O 2 ) has a concentration of about 0.1 mol or more.
5. A method of fabricating a metal wiring on a substrate, comprising:
forming a first metal layer on a substrate;
forming a second metal layer on the first metal layer; and
simultaneously etching the first metal layer and the second metal layer with an etchant comprising hydrogen peroxide (H 2 O 2 ) and one of carboxylic acid, carboxylate salt, and acetyl group (CH 3 CO—), wherein the etchant further comprises fluorine (F).
6. The method according to claim 1 , wherein the first metal layer is titanium (Ti), and the second metal layer is copper (Cu).
7. The method according to claim 2 , wherein one of ammonium acetate (CH 3 COONH 4 ), sodium acetate (CH 3 COONa), and potassium acetate (CH 3 COOK) has a concentration of about 0.5 wt % or more, and the hydrogen peroxide (H 2 O 2 ) has a concentration of about 0.1 mol or more.