A modified transparent conducting oxide for flat panel displays only

To keep up with the current development trends of thin film transistor liquid-crystal display (TFF-LCD), two major requirements must be satisfied in the transparent conducting oxide (TCO)-meterial itself. First, there must be no etch residue after TCO patterning and good etch selectivity against low electrical resistivity metals. Second, there must be good chemical endurance of the TCO material to secure a good electrical signal that is transported from the controller to the TFT-LCD by way of contact between the TCO and the tape carrier package (TCP). To obtain a new TCO material to achieve the kind of trade-off behavior that a TCO film has, the method in which ZnO is alloyed into indium tin oxide (ITO) was studied. It was determined that the 2.0-4.0 wt% ZnO-alloyed ITO film (named ITZO) is desirable in order to obtain a well-defined patterning ability and the stable TCP-contact property simultaneously. It is concluded that ITZO film can replace ITO and IZO for the pixel electrodes of a TFT-LCD designed with specifications for high resolution and large display size.