Display substrate and method of manufacturing the same

1. A method of manufacturing a display substrate, the method comprising:

forming a signal line, a thin-film transistor electrically connected to the signal line, and a key pattern on a substrate;

forming a light-blocking layer on the substrate to cover the signal line, the thin-film transistor and the key pattern;

forming an alignment key on the light-blocking layer, a position of the alignment key on the light-blocking layer corresponding to a position of the key pattern on the substrate;

aligning an exposure apparatus above the substrate using the alignment key; and

patterning the light-blocking layer using the exposure apparatus to form a light-blocking pattern on the substrate.

2. The method of claim 1 , wherein the alignment key comprises an alignment metal part covering the key pattern.

3. The method of claim 2 , wherein the alignment metal part is formed on the light-blocking layer by a chemical vapor deposition repair apparatus.

4. The method of claim 1 , wherein the alignment key comprises an alignment groove formed in the light-blocking pattern to expose the key pattern therethrough.

5. The method of claim 4 , wherein the alignment groove is formed by removing a portion of the light-blocking layer using a laser repair apparatus.

6. The method of claim 1 , further comprising:

forming a color filter in a unit pixel area of the substrate; and

forming a pixel electrode electrically connected to the thin-film transistor on the color filter.

7. The method of claim 6 , wherein the substrate comprises:

a display area including the signal line, the thin-film transistor, the color filter and the pixel electrode formed therein; and

a peripheral area surrounding an outer periphery of the display area, the peripheral area including the key pattern formed therein.

8. The method of claim 7 , wherein

the substrate further comprises a boundary line defining the outer periphery of the display area, and

the method further comprises cutting the substrate along the boundary line.

9. The method of claim 7 , further comprising forming a plurality of the key patterns on the substrate, wherein

the outer periphery of the display area has a rectangular shape,

key patterns of the plurality of key patterns have a rectangular shape, and

the key patterns are formed proximate to four opposite corners of the outer periphery of the display area.

10. The method of claim 9 , wherein the key patterns are formed in the peripheral area.

11. The method of claim 9 , wherein the key patterns are formed in the display area.

12. The method of claim 6 , wherein the forming the color filter is performed before the forming the light-blocking layer.

13. The method of claim 12 , wherein the forming the color filter comprises:

forming a color filter layer on the substrate to cover the signal line, the thin-film transistor and the key pattern; and

patterning the color filter layer to form the color filter.

14. The method of claim 13 , wherein the patterning the color filter layer comprises:

aligning a mask on the substrate using the key pattern.

15. The method of claim 6 , wherein the forming the color filter is performed after the forming the light-blocking pattern.

16. The method of claim 15 , wherein the forming the color filter comprises:

jetting a color filter ink into the unit pixel area on an area of the substrate on which the light-blocking pattern is not formed; and

drying the color filter ink to form the color filter.