Color filter using surface plasmon, liquid crystal display device and method for fabricating the same

• US 8,749,736 B2
• Filed: 11/08/2010
• Issued: 06/10/2014
• Est. Priority Date: 12/18/2009
• Status: Expired due to Fees

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Yoon, Min-Sung
• Primary Examiner(s): Won, Bumsuk
• Assistant Examiner(s): CHANG, CHARLES S
• Application Number:
  US12/941,846
• Publication Number:
  US 20110149217A1
• Time in Patent Office: 1,310 Days
• Field of Search: 349106-109
• US Class Current: 349/109
• CPC Class Codes: G02B 5/008 Surface plasmon devices diffractive gratings with a pitch less than or comparable to the wavelength G02B5/1809; surface plasmons in integrated optics G02B6/1226; optical analysis of materials by means of surface plasmons G01N21/553
• CPC Class Codes: G02B 5/201 in the form of arrays
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/1343 Electrodes reflective electrodes G02F1/133553
• CPC Class Codes: G02F 2201/121 common or background
• CPC Class Codes: G02F 2203/055 wavelength filtering
• CPC Class Codes: G02F 2203/10 plasmon
• CPC Class Codes: G02F 2203/34 Colour display without the use of colour mosaic filters

Abstract

Discussed are a color filter using a surface plasmon, a liquid crystal display (LCD) device and a method for fabricating the same, capable of enhancing a transmittance rate of an LC panel, by forming a transmissive pattern having a plurality of sub-wavelength holes having a period at a metal layer so that light of a specific wavelength can be selectively transmitted, and capable of simplifying the entire processed.

Claims

1. A liquid crystal display (LCD) device, comprising:

a first substrate;

a color filter formed on the first substrate, for implementing desired colors by forming, in metal layers, a plurality of sub-wavelength holes each having a different period;

a plurality of non-penetrating grooves formed at a region encompassing the plurality of hole;

an insulating layer formed on the metal layers including an inside of the plurality of holes and grooves, and formed of a same dielectric material as that of the first substrate;

a thin film transistor (TFT) formed on the insulating layer, and formed at an intersection between a gate line and a data line arranged in horizontal and vertical directions to define a pixel region; and

a second substrate bonded to the first substrate with facing the first substrate,

wherein the second substrate includes no color filter and no black matrix.

2. The LCD device of claim 1, wherein each thickness of the metal layer corresponding to each color is differently controlled.

5. The LCD device of claim 1, wherein the plurality of holes are formed in the pixel region except for a region where the gate line, the data line and the thin film transistor are formed.

3. A liquid crystal display (LCD) device, comprising:

a first substrate;

a color filter formed on an outer surface of the first substrate, for implementing desired colors by forming, in metal layers, a plurality of sub-wavelength holes each having a different period;

a plurality of non-penetrating grooves formed at a region encompassing the plurality of holes;

an insulating layer formed on the metal layers including an inside of the plurality of holes and grooves, and formed of a same dielectric material as that of the first substrate;

a thin film transistor (TFT) formed on an inner surface of the first substrate, and formed at an intersection between a gate line and a data line arranged in horizontal and vertical directions to define a pixel region; and

a second substrate bonded to the first substrate with facing the first substrate,

wherein the second substrate includes no color filter and no black matrix.

4. The LCD device of claim 3, wherein each thickness of the metal layer corresponding to each color is differently controlled.

6. The LCD device of claim 3, wherein the plurality of holes are formed in the pixel region except for a region where the gate line, the data line and the thin film transistor are formed.

7. A liquid crystal display (LCD) device, comprising:

a thin film transistor (TFT) formed on a first substrate, and formed at an intersection between a gate line and a data line arranged in horizontal and vertical directions to define a pixel region;

a second substrate;

a color filter formed on the second substrate, for implementing desired colors by forming, in metal layers, a plurality of sub-wavelength holes each having a different period;

a plurality of non-penetrating grooves formed at a region encompassing the plurality of holes; and

an insulating layer formed on the metal layers including an inside of the plurality of holes and grooves, and formed of a same dielectric material as that of the second substrate,

wherein the first substrate is bonded to the second substrate with facing the second substrate, and the color filter replaces a common electrode or a back electrode.

8. The LCD device of claim 7, further comprising a plurality of non-penetrating grooves having a period and formed near the plurality of holes having a period.

9. The LCD device of claim 7, wherein a horizontal sectional surface of the hole has one of a circular shape, a quadrangular shape, a triangular shape, an oval shape, and a slit shape having an aspect ratio more than one.

10. The LCD device of claim 7, wherein a horizontal sectional surface of the groove has one of a circular shape, a quadrangular shape, a triangular shape, an oval shape, and a slit shape having an aspect ratio more than one.

11. The LCD device of claim 7, wherein the metal layer is formed of a conductive material including at least one selected from a group consisting of aluminum (Al), gold (Au), silver (Ag), platinum (Pt), copper (Cu), nickel (Ni), palladium (Pd), zinc (Zn), iron (Fe), chrome (Cr), molybdenum (Mo), a doped semiconductor device, carbon nanotube, fullerene, conductive plastic, and electrical conductive composite material, or a mixture thereof.

12. The LCD device of claim 7, wherein each thickness of the metal layer corresponding to each color is differently controlled.

13. The LCD device of claim 7, wherein the plurality of holes are formed in the pixel region except for a region where the gate line, the data line and the thin film transistor are formed.

14. A method for fabricating a liquid crystal display (LCD) device, the method comprising:

providing first and second substrates;

forming, on the first substrate, a color filter for implementing desired colors by forming, in metal layers, a plurality of sub-wavelength holes each having a period;

forming a plurality of non-penetrating grooves formed at a region encompassing the plurality of holes;

forming an insulating layer on the metal layers including an inside of the plurality of holes and grooves, and formed of a same dielectric material as that of the first substrate;

forming a thin film transistor (TFT) on the insulating layer, and formed at an intersection between a gate line and a data line arranged in horizontal and vertical directions to define a pixel region; and

bonding the first substrate and the second substrate to each other, wherein the second substrate includes no color filter and no black matrix.

15. The method of claim 14, wherein each thickness of the metal layer corresponding to each color is differently controlled.

16. The method of claim 14, wherein the plurality of holes are formed in the pixel region except for a region where the gate line, the data line and the thin film transistor are formed.

17. A method for fabricating a liquid crystal display (LCD) device, the method comprising:

providing first and second substrates;

forming, on an outer surface of the first substrate, a color filter for implementing desired colors by forming, in metal layers, a plurality of sub-wavelength holes each having a period;

forming a plurality of non-penetrating grooves formed at a region encompassing the plurality of holes;

forming an insulating layer on the metal layers including an inside of the plurality of holes and grooves, and formed of a same dielectric material as that of the first substrate;

forming a thin film transistor (TFT) on an inner surface of the first substrate, and formed at an intersection between a gate line and a data line arranged in horizontal and vertical directions to define a pixel region; and

bonding the first substrate and the second substrate to each other, wherein the second substrate includes no color filter and no black matrix.

18. The method of claim 17, wherein each thickness of the metal layer corresponding to each color is differently controlled.

19. The method of claim 17, wherein the plurality of holes are formed in the pixel region except for a region where the gate line, the data line and the thin film transistor are formed.

20. A method for fabricating a liquid crystal display (LCD) device, the method comprising:

providing first and second substrates;

forming a thin film transistor on the first substrate, and formed at an intersection between a gate line and a data line arranged in horizontal and vertical directions to define a pixel region;

forming, on the second substrate, a color filter for implementing desired colors by forming, in metal layers, a plurality of sub-wavelength holes each having a period;

forming a plurality of non-penetrating grooves formed at a region encompassing the plurality of holes;

forming an insulating layer on the metal layers including an inside of the plurality of holes and grooves, and formed of a same dielectric material as that of the second substrate; and

bonding the first substrate and the second substrate to each other, wherein the color filter replaces a common electrode or a back electrode.

21. The method of claim 20, further comprising forming a plurality of non-penetrating grooves near the plurality of holes having a period.

22. The method of claim 20, wherein a horizontal sectional surface of the hole has one of a circular shape, a quadrangular shape, a triangular shape, an oval shape, and a slit shape having an aspect ratio more than one.

23. The method of claim 20, wherein a horizontal sectional surface of the groove has one of a circular shape, a quadrangular shape, a triangular shape, an oval shape, and a slit shape having an aspect ratio more than one.

24. The method of claim 20, wherein the metal layer is formed of a conductive material including at least one selected from a group consisting of aluminum (Al), gold (Au), silver (Ag), platinum (Pt), copper (Cu), nickel (Ni), palladium (Pd), zinc (Zn), iron (Fe), chrome (Cr), molybdenum (Mo), a doped semiconductor device, carbon nanotube, fullerene, conductive plastic, and electrical conductive composite material, or a mixture thereof.

25. The method of claim 20, wherein each thickness of the metal layer corresponding to each color is differently controlled.

26. The method of claim 20, wherein the plurality of holes are formed in the pixel region except for a region where the gate line, the data line and the thin film transistor are formed.

27. The method of claim 20, wherein the metal layers are formed by using one of a gas phase method, a liquid phase method, a solid phase method, and a nanosol coating method.

28. The method of claim 20, wherein the plurality of holes are formed by using one of an e-beam lithography, an ion beam milling, a nanosphere lithography, a nano imprinting, a photolithography, and a laser interference lithography.

29. The method of claim 20, wherein the plurality of grooves are formed by one of an etching process, a milling process, and a metal deposition process.