Display device and touch sensing method thereof

A display device comprising:

• a substrate;
• a driving element disposed on the substrate;
• a sensing element disposed on a same layer as the driving element and configured to transmit a sensing signal for sensing a touch;
• a passivation layer covering the driving element;
• a pixel electrode disposed on the passivation layer and connected to the driving element, wherein the passivation layer is between the substrate and the pixel electrode;
• an organic emission layer disposed on the pixel electrode and configured to emit light toward the substrate;
• a common electrode disposed on the organic emission layer;
• a touch electrode disposed between the substrate and the passivation layer and configured to form a capacitance with a touch object,
• wherein the touch electrode includes a semiconductor layer of the sensing element;
• and
• an auxiliary electrode disposed on a same layer as the pixel electrode and separated from the pixel electrode,
• wherein the auxiliary electrode is connected to the touch electrode.

A display device comprising:

• a substrate;
• a driving element disposed on the substrate;
• a sensing element disposed on a same layer as the driving element and configured to transmit a sensing signal for sensing a touch;
• a passivation layer covering the driving element;
• a pixel electrode disposed on the passivation layer and connected to the driving element, wherein the passivation layer is between the substrate and the pixel electrode;
• a gate insulation layer disposed between the substrate and the passivation layer;
• an organic emission layer disposed on the pixel electrode and configured to emit light toward the substrate;
• a common electrode disposed on the organic emission layer;
• and
• a touch electrode disposed between the substrate and the passivation layer and configured to form a capacitance with a touch object,
• wherein the driving element includes a first gate electrode and a second gate electrode disposed on the first gate electrode, the first gate electrode and the second gate electrode being disposed between the substrate and the passivation layer,
• wherein the touch electrode and the first gate electrode are both directly disposed on a same surface of the gate insulation layer and are directly connected together.