A thin film transistor including a gate electrode, a semiconductor layer, a gate insulating layer, a source electrode, a drain electrode and a graphene pattern. The semiconductor layer overlaps with the gate electrode. The gate insulating layer is disposed between the gate electrode and the semiconductor layer. The source electrode overlaps with the semiconductor layer. The drain electrode overlaps with the semiconductor layer. The drain electrode is spaced apart from the source electrode. The graphene pattern is disposed between the semiconductor layer and at least one of the source electrode and the drain electrode.