Patent ID: 7170571

Claim:
A liquid crystal display device, comprising: a substrate; a gate electrode over the substrate; a first semiconductor layer over the substrate; a source electrode and a drain electrode over the first semiconductor layer, the source and drain electrodes having a first metal layer and a second metal layer formed in a same pattern and defining and forming a separation between the source electrode and drain electrode, wherein the second metal layer is adapted to be a dry etching mask to pattern the first metal layer so that etched side-walls of the first metal layer and the second metal layer are substantially aligned instead of being over-etched when the device is manufactured; a gate insulating film over the gate electrode and between the substrate and the first semiconductor layer; a second semiconductor layer between the first metal layer and the first semiconductor layer, the second semiconductor layer defining a portion of the separation region in the same pattern as the first and second metal layers; a protective layer over the source and drain electrodes; and a pixel electrode provided on the protective layer.