Method of manufacturing a thin-film transistor and method of manufacturing a display substrate using the same

A method for providing maskless patterning, the method comprising:

• forming a gate pattern comprising a gate line and a gate electrode of a thin film transistor (TFT) on a substrate;
• disposing a gate insulating layer, a semiconductor layer, an ohmic contact layer and source metal layer of the substrate;
• forming a first photoresist pattern comprising a first photo pattern and a second photo pattern using a digital exposure device generating a plurality of spot beams, the first photo pattern being formed to a first region of the substrate and having a first thickness, the second photo pattern being formed to a second region adjacent to the first region and having a second thickness and a width in a range of about 50% to about 60% of the respective diameters of the plurality of spot beams, the second thickness of the second pattern being smaller than the first thickness of the first pattern, wherein the plurality of the spot beams are irradiated overlapping with each other and in the first region and the second region;
• patterning the source metal layer using the first photoresist pattern as an etching mask to form a source pattern comprising a source electrode and a drain electrode, the source electrode and the drain electrode being spaced apart from each other based on the second region, wherein the first region comprises an active pattern;
• and
• forming a pixel electrode formed on the substrate having the source pattern and electrically being connected to the drain electrode.