Patent ID: 8198631

Claim:
A method of fabricating a display device, the method comprising: forming a buffer layer on a substrate and made of an inorganic insulating material; forming a gate electrode, a gate insulating layer, an active layer and an auxiliary active layer sequentially disposed on the buffer layer, wherein the gate electrode and the gate insulating layer have substantially the same shape and area in plane, wherein the active layer and the auxiliary active layer have substantially the same shape and area in plane, wherein side portions of the gate insulating layer are not covered by the active layer, wherein the gate electrode is made of extrinsic polycrystalline silicon, wherein the active layer is made of intrinsic polycrystalline silicon, and wherein the auxiliary active layer is made of intrinsic amorphous silicon; forming an insulating interlayer on the auxiliary active layer and made of an inorganic insulating material, wherein the insulating interlayer includes an active contact hole exposing each of both side portions of the auxiliary active layer; forming an ohmic contact layer, source and drain electrodes and a data line, wherein the ohmic contact layer is made of extrinsic amorphous silicon and contacts each of the both side portions of the auxiliary active layer, wherein each of the source and drain electrodes is on the ohmic contact layer, and wherein the data line is on the insulating interlayer; forming a first passivation layer on the source and drain electrodes and the data line; patterning the first passivation layer, the insulating interlayer and the gate insulating layer to form a gate contact hole exposing the gate electrode; forming a gate line on the first passivation layer, made of a metal material, crossing the data line to define a pixel region, and contacting the gate electrode through the gate contact hole; forming a second passivation layer on the gate line; patterning the first and second passivation layers to form a drain contact hole exposing the drain electrode; and forming a pixel electrode on the second passivation layer in the pixel region and contacting the drain electrode through the drain contact hole.