MATERIAL FOR PIXEL ELECTRODE OF LCD AND ETCHING METHOD THEREOF

摘要

PURPOSE: A pixel electrode material of an LCD(Liquid Crystal Display) is provided to prevent the corrosion or damage of a metal line in a process of patterning a pixel electrode. CONSTITUTION: A passivation layer(7) is formed on a transparent substrate(1). The passivation layer is patterned together with an active layer(4) and a gate insulating film(3) by photolithography to remain at a TFT(Thin Film Transistor), a pixel area and a pad area. A gate line(2b) is exposed, and contact holes(8,9) for exposing a drain electrode(6b) and a gate pad(2c) are formed on the passivation layer. Then, amorphous transparent conductive material such as IZO(Indium Zinc Oxide), ITZO(Indium Tin Zinc Oxide) or a-ITO(Amorphous Indium Tin Oxide) is deposited on the transparent substrate as pixel electrode material. A pixel electrode(10a) and a protection electrode(10b) are exposed, developed and wet-etched. The patterned pixel electrode is contacted with the drain electrode via the contact hole(8) while the protection electrode is contacted with the gate pad and the data pad via the contact hole(9). The pixel electrode layer made of amorphous transparent conductive material is etched by weak acid easily and rapidly. Therefore, the gate metal layer is prevented from corrosion or damage.