Display device and method of fabricating the same

A display device comprising:

• a substrate;
• a semiconductor layer disposed on the substrate and comprising a first area and a second area;
• a first conductive layer disposed on the semiconductor layer and comprising a first gate pattern overlapping with the first area and a second gate pattern overlapping with the second area;
• and
• a first gate insulating layer disposed between the semiconductor layer and the first conductive layer and comprising a first insulating layer overlapping the first area and the second area, and a second insulating layer not overlapping the first area but overlapping the second area,
• wherein the first insulating layer has a dielectric constant greater than that of the second insulating layer, and
• wherein the second insulating layer is disposed on the first insulating layer.

A method of fabricating a display device, the method comprising:

• forming a semiconductor layer comprising a first area and a second area on a substrate;
• sequentially forming a first insulating layer on the semiconductor layer, a second insulating layer on the first insulating layer, and a third insulating layer on the second insulating layer;
• forming a photoresist layer overlapping the first area on the third insulating layer;
• etching a part of the third insulating layer that overlaps the second area using the photoresist layer as an etch stop layer;
• and
• removing the photoresist layer and then forming a first gate pattern on the third insulating layer overlapping the first area and a second gate pattern on the second insulating layer overlapping with the second area,
• wherein a dielectric constant of the second insulating layer is greater than a dielectric constant of the first insulating layer and a dielectric constant of the third insulating layer.