Display device

• US 8,659,516 B2
• Filed: 10/12/2012
• Issued: 02/25/2014
• Est. Priority Date: 06/06/2000
• Status: Expired due to Term

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Koyama, Jun
• Primary Examiner(s): NGUYEN, JENNIFER T
• Application Number:
  US13/650,441
• Publication Number:
  US 20130093650A1
• Time in Patent Office: 501 Days
• Field of Search: 345/47, 345 76-100, 345/204, 345690-693, 257/351, 257/344, 257/412, 257/69, 257/72, 257/59, 257/408
• US Class Current: 345/76
• CPC Class Codes: G09G 2300/08 Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
• CPC Class Codes: G09G 2310/027 Details of drivers for data electrodes, the drivers handling digital grey scale data, e.g. use of D/A converters
• CPC Class Codes: G09G 3/2014 by modulation of the duration of a single pulse during which the logic level remains constant
• CPC Class Codes: G09G 3/30 using electroluminescent panels
• CPC Class Codes: H01L 2029/7863 with an LDD consisting of more than one lightly doped zone or having a non-homogeneous dopant distribution, e.g. graded LDD
• CPC Class Codes: H01L 27/12 the substrate being other than a semiconductor body, e.g. an insulating body
• CPC Class Codes: H01L 27/1214 comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/1259 Multistep manufacturing methods
• CPC Class Codes: H01L 27/127 with a particular formation, treatment or patterning of the active layer specially adapted to the circuit arrangement
• CPC Class Codes: H01L 29/66757 Lateral single gate single channel transistors with non-inverted structure, i.e. the channel layer is formed before the gate
• CPC Class Codes: H01L 29/78621 with LDD structure or an extension or an offset region or characterised by the doping profile
• CPC Class Codes: H01L 29/78645 with multiple gate

Abstract

A signal line driving circuit which includes a digital signal sampling circuit, a storage circuit, a time setting circuit and a constant current circuit, is fabricated of TFTs on an insulating substrate which is made of the same substance as that of a pixel portion substrate. Thus, in a passive type EL display device, the problem of a distortion in the case of bonding the signal line driving circuit onto the pixel portion substrate can be eliminated. Besides, in an active type EL display device, each pixel is constructed of one transistor and an EL element. Thus, the aperture factor of the EL display device is enlarged.

Claims

1. A display device comprising:

a first substrate;

a pixel portion over the first substrate;

a source driver circuit over the first substrate, the source driver circuit comprising;

a first circuit comprising an op amp;

a second circuit comprising a latch circuit, wherein an output of the second circuit is operationally connected to an input terminal of the first circuit,

a first line electrically connected to the pixel portion, wherein the first line is operationally connected to an output terminal of the first circuit;

a second substrate over the first substrate with the pixel portion, the source driver circuit, and the first line interposed therebetween;

a first sealing material interposed between the first substrate and the second substrate, wherein the first sealing material is disposed along peripheries of the first and second substrates; and

a second sealing material formed outside of the first sealing material, wherein the second sealing material is in contact with side surfaces of the first and second substrates,

wherein both the first sealing material and the second sealing material surround the pixel portion.

2. The display device according to claim 1, further comprising a filler filled in an area surrounded by the first sealing material, the first substrate, and the second substrate.

3. The display device according to claim 2, wherein the filler includes a hygroscopic substance.

4. The display device according to claim 3, wherein the hygroscopic substance comprises barium oxide.

5. The display device according to claim 1, wherein the first circuit comprises a constant current circuit.

6. The display device according to claim 1, wherein the input terminal of the first circuit is electrically connected to an output terminal of a time setting circuit, and wherein an input terminal of the time setting circuit is electrically connected to an output terminal of the second circuit.

7. A display module comprising the display device according to claim 1 and an FPC.

8. An electronic equipment comprising the display module according to claim 7 and at least one of an operation switch, a battery, and a sound input portion.

9. The display device according to claim 1, wherein the first line is a source signal line.

10. A display device comprising:

a first substrate;

a pixel portion including a light emitting element over the first substrate;

a source driver circuit over the first substrate, the source driver circuit comprising;

a first circuit comprising an op amp;

a second circuit comprising a latch circuit, wherein an output of the second circuit is operationally connected to an input terminal of the first circuit,

a first line and a second line electrically connected to the pixel portion, wherein the first line is operationally connected to an output terminal of the first circuit and the second line is not directly connected to the first line;

a second substrate over the first substrate with the pixel portion, the source driver circuit, and the first line interposed therebetween;

a first sealing material interposed between the first substrate and the second substrate, wherein the first sealing material is disposed along peripheries of the first and second substrates; and

a second sealing material formed outside of the first sealing material, wherein the second sealing material is in contact with side surfaces of the first and second substrates,

wherein both the first sealing material and the second sealing material surround the pixel portion.

11. The display device according to claim 10, further comprising a filler filled in an area surrounded by the first sealing material, the first substrate, and the second substrate.

12. The display device according to claim 11, wherein the filler includes a hygroscopic substance.

13. The display device according to claim 12, wherein the hygroscopic substance comprises barium oxide.

14. The display device according to claim 10, wherein the first circuit comprises a constant current circuit.

15. The display device according to claim 10, wherein the input terminal of the first circuit is electrically connected to an output terminal of a time setting circuit, and wherein an input terminal of the time setting circuit is electrically connected to an output terminal of the second circuit.

16. A display module comprising the display device according to claim 10 and an FPC.

17. An electronic equipment comprising the display module according to claim 16 and at least one of an operation switch, a battery, and a sound input portion.

18. The display device according to claim 10, wherein the first line is a source signal line.

19. The display device according to claim 10, wherein the second line is a power supply line.

20. A display device comprising:

a first substrate;

a pixel portion over the first substrate;

a source driver circuit over the first substrate, the source driver circuit comprising;

a first circuit comprising an op amp;

a second circuit comprising a latch circuit, wherein an output of the second circuit is operationally connected to an input terminal of the first circuit,

a first line and a second line electrically connected to the pixel portion, wherein the first line is operationally connected to an output terminal of the first circuit and the second line is not directly connected to the first circuit;

a second substrate over the first substrate, wherein the first substrate extends beyond an edge of the second substrate;

a first sealing material interposed between the first substrate and the second substrate, wherein the first sealing material is disposed along peripheries of the first and second substrates; and

a second sealing material formed outside of the first sealing material, wherein the second sealing material is in contact with side surfaces of the first and second substrates,

wherein a portion of the second sealing material is disposed over an upper surface of the first substrate which extends beyond the edge of the second substrate, and

wherein both the first sealing material and the second sealing material surround the pixel portion.

21. The display device according to claim 20, further comprising a filler filled in an area surrounded by the first sealing material, the first substrate, and the second substrate.

22. The display device according to claim 21, wherein the filler includes a hygroscopic substance.

23. The display device according to claim 22, wherein the hygroscopic substance comprises barium oxide.

24. The display device according to claim 20, wherein the first circuit comprises a constant current circuit.

25. The display device according to claim 20, wherein the input terminal of the first circuit is electrically connected to an output terminal of a time setting circuit, and wherein an input terminal of the time setting circuit is electrically connected to an output terminal of the second circuit.

26. A display module comprising the display device according to claim 20 and an FPC.

27. An electronic equipment comprising the display module according to claim 26 and at least one of an operation switch, a battery, and a sound input portion.

28. The display device according to claim 20, wherein the first line is a source signal line.

29. The display device according to claim 20, wherein the second line is a power supply line.