Signal line, thin film transistor array panel with the signal line, and method for manufacturing the same

System and techniques for providing signal lines comprising copper alloys including at least one of molybdenum, tungsten, and chromium. The present disclosure provides a thin film transistor array panel comprising an insulating substrate; a gate line formed on the insulating substrate; a gate insulating layer formed on the gate line; a semiconductor layer formed on the gate insulating layer; ohmic contacts formed on the gate insulating layer and the semiconductor layer; a data line having a source electrode formed on one of the ohmic contacts and having a narrower width than the ohmic contact thereunder; a drain electrode facing the source electrode with a gap therebetween and having a narrower width than the ohmic contact thereunder; and a pixel electrode connected to the drain electrode, wherein at least one of the gate line and the data line comprises a Cu-alloy that contains Cu and one selected from molybdenum (Mo), tungsten (W), and chromium (Cr).