DISPLAY SUBSTRATE HAVING THE SAME AND METHOD OF MANUFACTURING THE DISPLAY SUBSTRATE

• US 20080185589A1
• Filed: 02/06/2008
• Published: 08/07/2008
• Est. Priority Date: 02/07/2007
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Jang-Soo, Chai, Chong-Chul, Shin, Kyoung-Ju
• Granted Patent: US 7,915,614 B2
• Time in Patent Office: Days
• US Class Current: 257/59
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: G02F 1/136222 Colour filters incorporated in the active matrix substrate

Abstract

A display substrate includes a thin-film transistor (TFT) layer, a color filter layer and a pixel electrode formed on a substrate. The TFT layer includes a gate line, a data line electrically insulated from the gate line and extending in a direction different from the gate line, a TFT electrically connected to the gate line and the data line, and a storage electrode formed from the same layer as the gate line in each pixel. The color filter layer includes a storage hole extending to a portion of the TFT layer corresponding to the storage electrode. The storage hole has a horizontal cross-sectional area greater than the storage electrode, wherein the horizontal cross-sectional area is measured in a plane parallel to the substrate. The pixel electrode is formed on the color filter layer and in the storage hole to form a storage capacitor with the storage electrode.

Claims

1. A display substrate comprising:

a substrate;

a thin-film transistor (TFT) layer formed on the substrate, the TFT layer including a gate line, a data line electrically insulated from the gate line by a gate insulating layer and extended in a direction different from the gate line, a TFT electrically connected to the gate line and the data line, and a storage electrode formed in each pixel, wherein the storage electrode is formed from a same layer as the gate line;

a color filter layer including a storage hole extending to a portion of the TFT layer corresponding to the storage electrode, the storage hole having a horizontal cross-sectional area greater than the storage electrode, wherein the horizontal cross-sectional area is measured in a plane parallel to the substrate; and

a pixel electrode formed on the color filter layer and in the storage hole over the storage electrode to form a storage capacitor, the gate insulating layer being interposed between the pixel electrode and the storage electrode.

2. The display substrate of claim 1, wherein the color filter layer comprises a red color filter, a green color filter and a blue color filter formed in each pixel.

3. The display substrate of claim 2, wherein the color filter layer has a thickness of about 2.5 μ

m to about 3.5 μ

m and a maximum difference in thicknesses of the red, green and blue color filters is about 2,000 Å

.

4. The display substrate of claim 2, the maximum difference in the opening widths of the storage holes among the red, green and blue color filters is about 3 μ

m, and a dielectric constant of each of the red, green and blue color filters is in a range of about 3.3 to about 3.5.

5. The display substrate of claim 1, further comprising a light-blocking layer covering an area between an edge portion of the storage hole and an edge portion of the storage electrode.

6. The display substrate of claim 5, wherein the light-blocking layer is formed from a same layer as the data line.

7. The display substrate of claim 6, wherein the light-blocking layer is in a floating state.

8. The display substrate of claim 1, further comprising a column spacer formed on the pixel electrode, the column spacer having a horizontal cross-sectional area greater than the storage hole.

9. The display substrate of claim 8, wherein the column spacer is formed using a material that blocks light.

10. The display substrate of claim 9, further comprising a light-blocking layer formed from a same layer as the data line and disposed at an edge portion of the column spacer.

11. A display apparatus comprising:

a display substrate including;

a substrate;

a TFT layer formed on the substrate, the TFT layer including a gate line, a data line electrically insulated from the gate line by a gate insulating layer and extended in a direction different from the gate line, a TFT electrically connected to the gate line and the data line, and a storage electrode formed in each pixel, wherein the storage electrode is formed from a same layer as the gate line;

a color filter layer including a storage hole extending to a portion of the TFT layer corresponding to the storage electrode, the storage hole having a horizontal cross-sectional area greater than the storage electrode, wherein the cross-sectional area is measured in a plane parallel to the substrate; and

a pixel electrode formed on the color filter layer and in the storage hole to overlap the storage electrode and form a storage capacitor, the gate insulating layer being interposed between the pixel electrode and the storage electrode;

a cover substrate positioned substantially parallel to the display substrate, the cover substrate including a common electrode formed on a surface of the cover substrate that faces the display substrate; and

a liquid crystal layer disposed between the display substrate and the cover substrate.

12. The display apparatus of claim 11, wherein the display substrate further comprises a light-blocking layer that is formed from a same layer as the data line and covers a portion between an edge of the storage hole and an edge of the storage electrode.

13. The display apparatus of claim 11, wherein the display substrate further comprises a column spacer that is formed on the pixel electrode corresponding to the storage hole and has a horizontal cross-sectional area greater than the storage hole.

14. The display apparatus of claim 13, wherein the column spacer is formed using a material that blocks light.

15. The display apparatus of claim 13, wherein the display substrate further comprises a light-blocking layer which is formed from a same layer as the data line and is disposed at an edge of the column spacer.

16. The display apparatus of claim 11, wherein the cover substrate further comprises a black matrix that corresponds to the storage hole and has a horizontal cross-sectional area greater than the storage hole.

17. The display apparatus of claim 16, wherein the display substrate further comprises a light-blocking layer that is formed from a same layer as the data line and corresponds to an edge portion of the black matrix.

18. The display apparatus of claim 16, wherein the display substrate further comprises a column spacer that is formed on the pixel electrode corresponding to the storage hole and has a horizontal cross-sectional area greater than the storage hole.

19. The display apparatus of claim 14, wherein the column spacer is formed using a material that blocks light.

20. The display apparatus of claim 14, wherein the display substrate further comprises a light-blocking layer which is formed from a same layer as the data line and is disposed at an edge portion of the column spacer.

21. A method of manufacturing a display substrate, comprising:

providing a substrate;

forming a TFT layer on the substrate, the TFT layer including a gate line, a data line electrically insulated from the gate line by a gate insulating layer, a TFT electrically connected to the gate line and the data line, and a storage electrode formed from a same layer as the gate lines in each pixel, the data line extending in a direction different from the gate line;

forming a color filter layer including a storage hole extending to a portion of the TFT layer corresponding to the storage electrode, the storage hole having a horizontal cross-sectional area greater than the storage electrode, wherein the horizontal cross-sectional area is measured in a plane parallel to the substrate; and

forming a pixel electrode on the color filter layer and in the storage hole, the pixel electrode overlapping the storage electrode to form a storage capacitor, the gate insulating layer being interposed between the pixel electrode and the storage electrode.

22. The method of claim 21, wherein forming the color filter layer comprises:

forming a red color filter;

forming a green color filter; and

forming a blue color filter.

23. The method of claim 22, wherein the red color filter, the green color filter and the blue color filter are formed using masks having a same design.

24. The method of claim 21, wherein the TFT layer further comprises a light-blocking layer which is formed from a same layer as the data line and covers a portion between an edge of the storage hole and an edge of the storage electrode.

25. The method of claim 21, further comprising forming a column spacer which is formed on the pixel electrode corresponding to the storage hole and has a horizontal cross-sectional area greater than the storage hole.

26. The method of claim 25, wherein forming the column spacer comprises using a material that blocks light.

27. The method of claim 26, further comprising forming a light-blocking layer from a same layer as the data line, the light-blocking layer being disposed at an end portion of the column spacer.