A COMPOSITION OF ETCHING SOLUTION FOR METAL FILM USING IN MANUFACTURING PROCESS OF THIN FILM TRANSISTOR LIQUID CRYSTAL DISPLAY AND ETCHING METHOD USING THE SAME

摘要

An etchant composition for a metal film used in the manufacturing process of a TFT-LCD device, and a method for etching a metal film by using the etchant composition are provided to control the etching velocity freely, to obtain a satisfactory taper profile angle of 30-60 degrees and to improve the alignment of pattern. An etchant composition comprises 1-40 wt% of a compound containing Fe^3+; 0.1-10.0 wt% of a fluorine compound; and 50-98.1 wt% of water, and contains no an acidic compound. Preferably the compound containing Fe^3+ is selected from the group consisting of FeCl3, Fe(NO3)3, Fe2(SO4)3, NH4Fe(SO4)2, Fe(ClO4)3, FePO4 and Fe(NH4)3(C2O4)3; and the fluorine compound is selected from the group consisting of NaF, NaHF2, NH4F, NH4HF2, NH4BF4, NH4F, HF, KF, KHF2, AlF3 and HBF4.