Transflective liquid crystal display device having groove in buffer layer and fabricating method thereof
View Patent ↗A color filter substrate for a transflective liquid crystal display device includes: a substrate having a plurality of pixel regions, each of the plurality of pixel regions having reflective and transmissive portions; a black matrix on the substrate; a buffer layer on the black matrix, the buffer layer having a groove corresponding to the black matrix; a color filter layer on the buffer layer, the color filter layer having a first thickness in the reflective portion and a second thickness in the transmissive portion wherein the first thickness is substantially half of the second thickness, the color filter layer having a step difference at a border between the reflective and transmissive portions; and a common electrode on the color filter layer.
1. A color filter substrate for a transflective liquid crystal display device, comprising:
a substrate having a plurality of pixel regions, each of the plurality of pixel regions having reflective and transmissive portions;
a black matrix on the substrate;
a buffer layer on the black matrix, the buffer layer having a groove corresponding to and over the black matrix;
a color filter layer on the buffer layer, the color filter layer having a first thickness in the reflective portion and a second thickness in the transmissive portion; and
a common electrode on the color filter layer.
2. The color filter substrate according to claim 1 , wherein the first thickness is substantially half of the second thickness, and the color filter layer has a step difference at a border between the reflective and transmissive portions.
3. The color filter substrate according to claim 2 , wherein the buffer layer includes one of a transparent organic insulating material group including benzocyclobutene (BCB) and acrylic resin.
4. The color filter substrate according to claim 3 wherein the buffer layer has a thickness within a range of about 2.5 μm to about 4.0 μm.
5. The color filter substrate according to claim 4 , wherein the step difference is within a range of about 2.0 μm to about 2.5 μm.
6. The color filter substrate according to claim 1 , wherein the black matrix has a plurality of first open portions corresponding to the plurality of pixel regions.
7. The color filter substrate according to claim 6 , wherein the buffer layer has a plurality of second open portions corresponding to the transmissive portion.
8. A fabricating method of a color filter substrate for a transflective liquid crystal display device, comprising:
forming a black matrix on a substrate having a plurality of pixel regions, each of the plurality of pixel regions having reflective and transmissive portions;
forming a buffer layer on the black matrix, the buffer layer having a groove corresponding to and over the black matrix;
forming a color filter layer on the buffer layer, the color filter layer having a first thickness in the reflective portion and a second thickness in the transmissive portion; and
forming a common electrode on the color filter layer.
9. The method according to claim 8 , wherein the first thickness is substantially half of the second thickness, and the color filter layer has a step difference at a border between the reflective and transmissive portions.
10. The method according to claim 9 , wherein the buffer layer includes one of a transparent organic insulating material group including benzocyclobutene (BCB) and acrylic resin.
11. The method according to claim 10 , wherein the buffer layer has a thickness within a range of about 2.5 μm to about 4.0 μm.
12. The method according to claim 11 , wherein the step difference is within a range of about 2.0 μm to about 2.5 μm.
13. The method according to claim 8 , wherein the black matrix has a plurality of first open portions corresponding to the plurality of pixel regions.
14. The method according to claim 13 , wherein the buffer layer has a plurality of second open portions corresponding to the transmissive portion.
15. A transflective liquid crystal display device, comprising:
first and second substrates facing into and spaced apart from each other;
a gate line on an inner surface of the first substrate;
a data line crossing the gate line to define a pixel region having reflective and transmissive portions;
a thin film transistor connected to the gate line and the data line;
a reflective layer in the reflective portion;
a transparent electrode in the transmissive portion, the transparent electrode being connected to the thin film transistor;
a black matrix on an inner surface of the second substrate;
a buffer layer on the black matrix, the buffer layer having a groove corresponding to and over the black matrix;
a color filter layer on the buffer layer, the color filter layer having a first thickness in the reflective portion and a second thickness in the transmissive portion;
a common electrode on the color filter layer; and
a liquid crystal layer interposed between the transparent electrode and the common electrode.
16. The device according to claim 15 , wherein the first thickness is substantially half of the second thickness, and the color filter layer has a step difference at a border between the reflective and transmissive portions.
17. The device according to claim 16 , wherein the liquid crystal layer has a third thickness in the reflective portion and a fourth thickness in the transmissive portion wherein the third thickness is substantially a half of the fourth thickness.
18. The device according to claim 17 , wherein the buffer layer has a thickness within a range of about 2.5 μm to about 4.0 μm, and wherein the step difference is within a range of about 2.0 μm to about 2.5 μm.
19. The device according to claim 15 , wherein the black matrix has a first open portion corresponding to the pixel region, and wherein the buffer layer has a second open portion corresponding to the transmissive portion.
20. A fabricating method of a transflective liquid crystal display device, comprising:
forming a gate line on a first substrate;
forming a data line crossing the gate line to define a pixel region having reflective and transmissive portions;
forming a thin film transistor connected to the gate line and the data line;
forming a reflective layer in the reflective portion;
forming a transparent electrode in the transmissive portion, the transparent electrode being connected to the thin film transistor;
forming a black matrix on a second substrate;
forming a buffer layer on the black matrix, the buffer layer having a groove corresponding to and over the black matrix;
forming a color filter layer on the buffer layer, the color filter layer having a first thickness in the reflective portion and a second thickness in the transmissive portion;
forming a common electrode on the color filter layer;
attaching the first and second substrates wherein the transparent electrode and the common electrode face into each other; and
forming a liquid crystal layer between the transparent electrode and the common electrode.
21. The method according to claim 20 , wherein the first thickness is substantially half of the second thickness, and the color filter layer has a step difference at a border between the reflective and transmissive portions.
22. The method according to claim 21 , wherein the liquid crystal layer has a third thickness in the reflective portion and a fourth thickness in the transmissive portion wherein the third thickness is substantially a half of the fourth thickness.
23. The method according to claim 22 , wherein the buffer layer has a thickness within a range of about 2.5 μm to about 4.0 μm, and wherein the step difference is within a range of about 2.0 μm to about 2.5 μm.
24. The method according to claim 20 , wherein the black matrix has a first open portion corresponding to the pixel region, and wherein the buffer layer has a second open portion corresponding to the transmissive portion.