Patent ID: 8614780

Claim:
A method of forming an array substrate for use in an in-plane switching liquid crystal display device, comprising: forming a gate line and a gate electrode on a substrate, the gate line being disposed in a first direction and the gate electrode extending from the gate line, wherein the gate electrode and the gate line have a first double-layered structure consisting of a first barrier layer and a first low resistance metallic layer; forming a gate pad connected to one end of the gate line; forming a common line substantially parallel and adjacent to the gate line; forming a data line in a second direction, the data line defining a pixel region with the gate line, wherein the data line has a second double-layered structure consisting of a second barrier layer and a second low resistance metallic layer; forming a data pad at one end of the data line; forming a plurality of common electrodes in a direction perpendicular to an adjacent gate line, the common electrodes extending from the common line to the pixel region; forming a thin film transistor near a crossing of the gate and data lines, the thin film transistor including a semiconductor layer, the gate electrode, a source electrode, and a drain electrode, wherein each of the source and drain electrodes has the same double-layered structure as the data line; forming a plurality of pixel electrodes in the direction perpendicular to the adjacent gate lines and connected to the drain electrode, wherein the pixel electrodes are arranged in an alternating pattern with the common electrodes; and forming another semiconductor layer extended under the data line, the data pad, and the plurality of pixel electrodes, wherein the another semiconductor layer is a double-layered structure consisting of a first layer of pure amorphous silicon and a second layer of doped amorphous silicon on the first layer, and wherein the first layer protrudes outside from both sides of each of the data line, the data pad and the plurality of pixel electrodes.