Patent ID: 7960221

Claim:
A method of manufacturing a thin film transistor substrate, comprising the steps of: forming a gate electrode and a gate line connected thereto on a substrate; forming a gate insulation film, an active layer and a conductive film on the substrate; applying a photosensitive film on the conductive film and patterning the photosensitive film to form a photosensitive mask pattern that shields a source electrode formation region having first and second protruding portions and a connecting portion for connecting them, a source line formation region connected to the source electrode formation region, and a drain electrode formation region partially extending into a region between the first and second protruding portions, that shields a channel formation region provided between the drain electrode formation region partially extending into the region between the first and second protruding portions, and the first and second protruding portions and the connecting portion, and that has a thickness of the photosensitive film of the channel formation region smaller than a thickness of the source and drain electrode formation regions; performing an etching process using the photosensitive mask pattern as an etching mask to remove the conductive film and the active layer in a region other than the source electrode formation region, the source line formation region, the drain electrode formation region and the channel formation region; lowering a height of the photosensitive mask pattern to expose the channel formation region; and removing the conductive film through an etching process using the photosensitive mask pattern with the exposed channel formation region as an etching mask to form a source electrode including the first and second protruding portions and the connecting portion, a source line connected to the source electrode, a drain electrode extending between the first and second protruding portions, and a channel region with the active layer exposed between the two electrodes, wherein the active layer protrudes outside the channel region by a length corresponding to 30% or less of the width of the source line formation region.