A display device includes an insulating substrate; a plurality of gate wires formed on the insulating substrate, the plurality of gate wires including a gate electrode; a gate insulating layer covering the plurality of gate wires; a transparent electrode layer formed on the gate insulating layer, the transparent electrode layer including a source electrode and a drain electrode disposed about the gate electrode and spaced apart from each other to define a channel region disposed therebetween; a plurality of data wires covering a predetermined portion of the transparent electrode layer and being crossed insulatedly with the plurality of gate wires to define pixels; and an organic semiconductor layer formed on the channel region for each pixel, a predetermined portion of the organic semiconductor layer being operatively connected with the source electrode, the drain electrode, and the gate electrode to form a transistor having an improved characteristic and a novel structure.