Display device and manufacturing method therefor

A display device with a plurality of thin film transistors, comprising:

• a plurality of gate electrodes;
• a gate insulating layer covering the plurality of gate electrodes;
• an oxide semiconductor layer on the gate insulating layer;
• and
• a metal layer composed of multiple layers including a lowermost layer and a middle layer, the lowermost layer being lower in an ionization tendency than the middle layer, the lowermost layer being in contact with and on the oxide semiconductor layer,
• wherein
• the oxide semiconductor layer includes a plurality of channel regions,
• the metal layer includes a plurality of first electrodes and a plurality of second electrodes,
• each of the plurality of channel regions is interposed between a corresponding one of the plurality of first electrodes and a corresponding one of the plurality of second electrodes, constituting a corresponding one of the plurality of thin film transistors,
• the oxide semiconductor layer is continuous between a pair of the plurality of channel regions included in an adjacent pair of the plurality of thin film transistors, and
• the metal layer is continuous between a pair of the plurality of first electrodes included in the adjacent pair of the plurality of thin film transistors.