Patent ID: 7333161

Claim:
An array substrate of a liquid crystal display device, comprising: a substrate; gate line disposed along a first direction on the substrate, the gate line including a storage electrode; a gate insulating layer on the gate line; a semiconductor layer on the gate insulating layer, wherein the semiconductor layer includes an active layer of amorphous silicon, an ohmic contact layer of doped amorphous silicon and a metal buffer layer of titanium or chromium; a pixel electrode of transparent conductive material and overlapping the gate line; a drain electrode of transparent conductive material and overlapping the semiconductor layer; a source electrode of transparent conductive material spaced apart from the drain electrode, the source electrode and the drain electrode being a single layer, a portion of the active layer between the source electrode and the drain electrode being exposed; a passivation layer including a first contact hole and an open portion, the first contact hole exposing the source electrode and the open portion exposing the pixel electrode, respectively; and a data line disposed along a second direction on the passivation layer, the data line connected to the source electrode through the first contact hole and crossing the gate line, wherein the source electrode is larger than a portion of the semiconductor layer corresponding to the source electrode so that a portion of the source electrode in the first contact hole is disposed between, and in direct contact with both of, the gate insulating layer and the data line.