A method of fabricating a display panel may include forming an oxide semiconductor pattern on a base layer including a first region and a second region, etching first, second, and third insulating layers to form a first groove that overlaps the second region, forming electrodes on the third insulating layer, forming a fourth insulating layer on the third insulating layer to cover the electrodes, thermally treating the fourth insulating layer, forming an organic layer to cover the fourth insulating layer, and forming an organic light emitting diode on the organic layer.