Method of manufacturing a display substrate and method of manufacturing a display apparatus using the same

A method of manufacturing a display apparatus, the method comprising:

• on a first base substrate, forming a gate line, a data line crossing the gate line, and a switching device electrically connected to the gate line and the data line;
• sequentially forming a passivation layer, a first resist layer and a second resist layer on the first base substrate;
• patterning the second resist layer using a developing solution to form an etch-stop pattern;
• patterning the first resist layer using the etch-stop pattern and the developing solution to form a resist pattern, the etch-stop pattern having a sidewall protruding from a sidewall of the resist pattern;
• after the patterning the first resist layer, removing a portion of the passivation layer using the resist pattern and the etch-stop pattern, to form a contact hole on a drain electrode of the switching device;
• forming a pixel electrode electrically connected to the switching device through the contact hole;
• forming a common electrode layer on a second base substrate, wherein the second base substrate is facing the first base substrate;
• and
• removing the first and second resist layers,
• wherein the first resist layer comprises a non-photosensitive resist composition and the second resist layer comprises a photosensitive resist composition.