A conductive layer for a thin film transistor (TFT) array panel includes a multi-layered portion defining a source electrode and a drain electrode of a TFT device, and includes a first sub-layer, a second sub-layer, a third sub-layer, and at least one additional sub-layer. The third and the first sub-layers include indium and zinc oxide materials. An indium to zinc content ratio in the first sub-layer is greater than that in the third sub-layer. An indium to zinc content ratio in the additional sub-layer is formulated between that in the first and the third sub-layers. The content ratio differentiation between the first and the third sub-layers affects a lateral etch profile associated with a gap generated in the second conductive layer between the source and the drain electrodes, where the associated gap width in the third sub-layer is wider than that in the first sub-layer.