A display device includes a semiconductor member, a first gate electrode, a pixel electrode, and a common electrode. The semiconductor member includes a source area, a drain area, and a channel area between the source area and the drain area. The first gate electrode includes a first gate barrier layer, a second gate barrier layer, and a gate metal layer. The first gate barrier layer overlaps the channel area. An oxide material of the first gate barrier layer is identical to an oxide material of the semiconductor member. The second gate barrier layer includes a metal oxide alloy and is positioned between the first gate barrier layer and the gate metal layer. The pixel electrode is electrically connected to the drain area. The common electrode overlaps the pixel electrode.