Liquid crystal display device

• US 10,424,674 B2
• Filed: 09/28/2017
• Issued: 09/24/2019
• Est. Priority Date: 11/28/2008
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Ishitani, Tetsuji, Kubota, Daisuke
• Primary Examiner(s): Gross, Alexander P
• Application Number:
  US15/718,243
• Publication Number:
  US 20180019345A1
• Time in Patent Office: 726 Days
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/136209 Light shielding layers, e.g. black matrix, incorporated in the active matrix substrate, e.g. structurally associated with the switching element
• CPC Class Codes: G02F 1/136222 Colour filters incorporated in the active matrix substrate
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: H01L 27/1225 with semiconductor materials not belonging to the group IV of the periodic table, e.g. InGaZnO
• CPC Class Codes: H01L 27/1248 with a particular composition or shape of the interlayer dielectric specially adapted to the circuit arrangement
• CPC Class Codes: H01L 29/78618 characterised by the drain or the source properties, e.g. the doping structure, the composition, the sectional shape or the contact structure silicide contacts, electrodes in general H01L29/458
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate

Abstract

To provide a liquid crystal display device suitable for a thin film transistor which uses an oxide semiconductor. In a liquid crystal display device which includes a thin film transistor including an oxide semiconductor layer, a film having a function of attenuating the intensity of transmitting visible light is used as an interlayer film which covers at least the oxide semiconductor layer. As the film having a function of attenuating the intensity of transmitting visible light, a coloring layer can be used and a light-transmitting chromatic color resin layer is preferably used. An interlayer film which includes a light-transmitting chromatic color resin layer and a light-blocking layer may be formed in order that the light-blocking layer is used as a film having a function of attenuating the intensity of transmitting visible light.

Claims

1. A display device comprising:

a thin film transistor comprising;

a gate electrode layer;

a first insulating layer over the gate electrode layer;

a channel formation region containing an oxide semiconductor, the channel formation region being over the first insulating layer and overlapping with the gate electrode layer;

an n-type region including one of a source region and a drain region; and

a second insulating layer over the channel formation region;

a pixel electrode layer electrically connected to the thin film transistor;

a light-transmitting chromatic color resin layer overlapping with the channel formation region; and

an electrode layer over the second insulating layer and overlapping with the gate electrode layer and the channel formation region,

wherein the channel formation region is included in a semiconductor layer,

wherein the n-type region includes crystals each having a diameter of 1 nm to 10 nm,

wherein the light-transmitting chromatic color resin layer has a light transmittance lower than a light transmittance of the semiconductor layer,

wherein the oxide semiconductor contains indium, gallium, and zinc,

wherein the n-type region contains indium, gallium, zinc and oxygen,

wherein the second insulating layer contains silicon and oxygen, and

wherein a length of the gate electrode layer is larger than a length of the semiconductor layer in a direction parallel to a channel length direction of the thin film transistor.

2. The display device according to claim 1,

wherein the light-transmitting chromatic color resin layer has a plurality of colors, and

wherein each pixel in the display device includes the light-transmitting chromatic color resin layer having one color of the plurality of colors.

3. The display device according to claim 1, wherein a light-blocking layer is over the thin film transistor with a display layer interposed therebetween.

4. The display device according to claim 1, wherein the electrode layer is a common electrode layer, and

wherein the common electrode layer is included between the light-transmitting chromatic color resin layer and a display layer.

5. The display device according to claim 1,

wherein the electrode layer is a common electrode layer,

wherein the common electrode layer is included between the light-transmitting chromatic color resin layer and a display layer, and

wherein the pixel electrode layer and the common electrode layer have an opening pattern.

6. The display device according to claim 1,

wherein the electrode layer is a common electrode layer,

wherein the common electrode layer is included between the light-transmitting chromatic color resin layer and a display layer, and

wherein the pixel electrode layer and the common electrode layer have a comb-shape.

7. The display device according to claim 3, wherein the display layer is a liquid crystal layer.

8. The display device according to claim 7, wherein the liquid crystal layer includes a liquid crystal material exhibiting a blue phase.

9. The display device according to claim 7, wherein the liquid crystal layer includes a chiral agent.

10. The display device according to claim 7, wherein the liquid crystal layer includes a photocurable resin and a photopolymerization initiator.

11. The display device according to claim 2, wherein the light-transmitting chromatic color resin layer overlaps with the pixel electrode layer.

12. The display device according to claim 2, further comprising a transparent insulating layer over the light-transmitting chromatic color resin layer.

13. The display device according to claim 2, wherein the n-type region is included in an n-type layer over the semiconductor layer.

14. A display device comprising:

a thin film transistor comprising;

a gate electrode layer;

a first insulating layer over the gate electrode layer;

a channel formation region, the channel formation region being over the first insulating layer and overlapping with the gate electrode layer;

an n-type region including one of a source and a drain;

a source electrode and a drain electrode over the channel formation region including an oxide semiconductor; and

a second insulating layer over the channel formation region;

a light-transmitting chromatic color resin layer over the second insulating layer;

a third insulating layer over and in direct contact with the light-transmitting chromatic color resin layer;

a pixel electrode layer electrically connected to one of the source electrode and the drain electrode of the thin film transistor; and

an electrode layer over the second insulating layer and overlapping with the gate electrode layer and the channel formation region,

wherein the channel formation region is included in a semiconductor layer,

wherein the n-type region includes crystals each having a diameter of 1 nm to 10 nm,

wherein the light-transmitting chromatic color resin layer has a light transmittance lower than a light transmittance of the semiconductor layer,

wherein the light-transmitting chromatic color resin layer covers the channel formation region and the n-type region,

wherein the oxide semiconductor contains indium, gallium, and zinc,

wherein the second insulating layer contains silicon and oxygen,

wherein the n-type region contains indium, gallium, zinc and oxygen,

wherein the pixel electrode layer contains indium tin oxide,

wherein a length of the gate electrode layer is larger than a length of the semiconductor layer in a direction parallel to a channel length direction of the thin film transistor.

15. The display device according to claim 14 further comprising a display layer over the third insulating layer.

16. The display device according to claim 15, wherein the display layer is a liquid crystal layer.

17. The display device according to claim 14, wherein the gate electrode layer contains copper.

18. The display device according to claim 14, wherein the source electrode and the drain electrode contain molybdenum and titanium.

19. The display device according to claim 14,

wherein the light-transmitting chromatic color resin layer has a plurality of colors, and

wherein each pixel in the display device includes the light-transmitting chromatic color resin layer having one color of the plurality of colors.

20. The display device according to claim 14,

wherein the electrode layer is a common electrode layer, and

wherein the common electrode layer is over the third insulating layer.

21. The display device according to claim 14, wherein the n-type region is included in an n-type layer over the semiconductor layer.

22. A display device comprising:

a thin film transistor comprising;

a gate electrode layer;

a first insulating layer over the gate electrode layer;

a channel formation region containing an oxide semiconductor, the channel formation region being over the first insulating layer and overlapping with the gate electrode layer;

an n-type region including one of a source region and a drain region; and

a second insulating layer over the channel formation region;

a pixel electrode layer electrically connected to the thin film transistor;

a light-transmitting chromatic color resin layer between the thin film transistor and the pixel electrode layer; and

an electrode layer over the second insulating layer and overlapping with the gate electrode layer and the channel formation region,

wherein the channel formation region is included in a semiconductor layer,

wherein the n-type region includes crystals each having a diameter of 1 nm to 10 nm,

wherein the light-transmitting chromatic color resin layer has a light transmittance lower than a light transmittance of the semiconductor layer,

wherein the oxide semiconductor contains indium, gallium, and zinc,

wherein the n-type region contains indium, gallium, zinc and oxygen,

wherein the second insulating layer contains silicon and oxygen, and

wherein a length of the gate electrode layer is larger than a length of the semiconductor layer in a direction parallel to a channel length direction of the thin film transistor.

23. The display device according to claim 22,

wherein the light-transmitting chromatic color resin layer has a plurality of colors, and

wherein each pixel in the display device includes the light-transmitting chromatic color resin layer having one color of the plurality of colors.

24. The display device according to claim 22, wherein a light-blocking layer is over the thin film transistor with a display layer interposed therebetween.

25. The display device according to claim 22, wherein the electrode layer is a common electrode layer, and

wherein the common electrode layer is included between the light-transmitting chromatic color resin layer and a display layer.

26. The display device according to claim 22,

wherein the electrode layer is a common electrode layer,

wherein the common electrode layer is included between the light-transmitting chromatic color resin layer and a display layer, and

wherein the pixel electrode layer and the common electrode layer have an opening pattern.

27. The display device according to claim 22,

wherein the electrode layer is a common electrode layer,

wherein the common electrode layer is included between the light-transmitting chromatic color resin layer and a display layer, and

wherein the pixel electrode layer and the common electrode layer have a comb-shape.

28. The display device according to claim 24, wherein the display layer is a liquid crystal layer.

29. The display device according to claim 28, wherein the liquid crystal layer includes a liquid crystal material exhibiting a blue phase.

30. The display device according to claim 28, wherein the liquid crystal layer includes a chiral agent.

31. The display device according to claim 28, wherein the liquid crystal layer includes a photocurable resin and a photopolymerization initiator.

32. The display device according to claim 22, wherein the light-transmitting chromatic color resin layer overlaps with the pixel electrode layer.

33. The display device according to claim 22, further comprising a transparent insulating layer over the light-transmitting chromatic color resin layer.

34. The display device according to claim 22, wherein the n-type region is included in an n-type layer over the semiconductor layer.

35. A display device comprising:

a thin film transistor comprising;

a gate electrode layer;

a first insulating layer over the gate electrode layer;

a channel formation region, the channel formation region being over the first insulating layer and overlapping with the gate electrode layer;

an n-type region including one of a source and a drain;

a source electrode and a drain electrode over the channel formation region including an oxide semiconductor; and

a second insulating layer over the channel formation region;

a light-transmitting chromatic color resin layer over the second insulating layer;

a third insulating layer over and in direct contact with the light-transmitting chromatic color resin layer;

a pixel electrode layer electrically connected to one of the source electrode and the drain electrode of the thin film transistor; and

an electrode layer over the second insulating layer and overlapping with the gate electrode layer and the channel formation region,

wherein the light-transmitting chromatic color resin layer is between the thin film transistor and the pixel electrode layer,

wherein the channel formation region is included in a semiconductor layer,

wherein the n-type region includes crystals each having a diameter of 1 nm to 10 nm,

wherein the light-transmitting chromatic color resin layer has a light transmittance lower than a light transmittance of the semiconductor layer,

wherein the oxide semiconductor contains indium, gallium, and zinc,

wherein the second insulating layer contains silicon and oxygen,

wherein the n-type region contains indium, gallium, zinc and oxygen,

wherein the pixel electrode layer contains indium tin oxide,

wherein a length of the gate electrode layer is larger than a length of the semiconductor layer in a direction parallel to a channel length direction of the thin film transistor.

36. The display device according to claim 35 further comprising a display layer over the third insulating layer.

37. The display device according to claim 36, wherein the display layer is a liquid crystal layer.

38. The display device according to claim 35, wherein the gate electrode layer contains copper.

39. The display device according to claim 35, wherein the source electrode and the drain electrode contain molybdenum and titanium.

40. The display device according to claim 35,

wherein the light-transmitting chromatic color resin layer has a plurality of colors, and

wherein each pixel in the display device includes the light-transmitting chromatic color resin layer having one color of the plurality of colors.

41. The display device according to claim 35,

wherein the electrode layer is a common electrode layer, and

wherein the common electrode layer is over the third insulating layer.

42. The display device according to claim 35, wherein the n-type region is included in an n-type layer over the semiconductor layer.