ETCHANT FOR THIN FILM TRANSISTOR-LIQUID CRYSTAL DISPLAYS

摘要

An etchant composition for etching a copper wire used in the circuit pattern of a TFT-LCD device is provided to improve stability and process margin by using no hydrogen peroxide and to enhance taper etch profile. An etchant composition comprises 0.1-50 wt% of ammonium persulfate((NH4)2S2O4); 0.01-5 wt% of an azole-based compound; and optionally 0.01-10 wt% of a fluorine-based compound. Preferably the azole-based compound comprises at least one selected from the group consisting of benzotriazole, aminotetrazole, imidazole and pyrazole; and the fluorine-based compound is at least one selected from the group consisting of hydrofluoric acid, ammonium fluoride, ammonium bifluoride, potassium fluoride and sodium fluoride.