Wiring substrate and display device including the same

A display device comprising:

• a display area and a pad area disposed on a side of the display area;
• a plurality of conductive layers disposed on a first substrate in the display area and the pad area and comprising a wiring and a conductive pattern;
• a via layer disposed on the plurality of conductive layers;
• a plurality of electrodes disposed on the via layer in the display area and spaced apart from each other;
• and
• a light emitting element disposed on at least one of the plurality of electrodes, wherein
• at least one of the plurality of conductive layers comprises:
• a first metal layer;
• a second metal layer disposed on the first metal layer;
• and
• a third metal layer disposed on the second metal layer,
• the second metal layer comprises copper (Cu),
• the third metal layer comprises a copper alloy, and
• a grain size of the third metal layer is smaller than a grain size of the second metal layer.