Electroluminescence display device

• US 8,957,424 B2
• Filed: 03/24/2014
• Issued: 02/17/2015
• Est. Priority Date: 11/19/1999
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Ono, Koji, Suzawa, Hideomi, Arao, Tatsuya
• Primary Examiner(s): Diaz, Jose R
• Application Number:
  US14/223,366
• Publication Number:
  US 20140203309A1
• Time in Patent Office: 330 Days
• Field of Search: 257/72, 257/59, 257/E29.137, 257/E29.278, 257/79, 257/88, 257/89, 257/98, 349/153, 349/155
• US Class Current: 257/72
• CPC Class Codes: G02F 1/13624 having more than one switching element per pixel
• 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 27/1222 with a particular composition, shape or crystalline structure of the active layer
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52
• 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 29/42384 for thin film field effect transistors, e.g. characterised by the thickness or the shape of the insulator or the dimensions, the shape or the lay-out of the conductor
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• 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 29/78627 with a significant overlap between the lightly doped drain and the gate electrode, e.g. GOLDD
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H01L 33/08 with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/62 Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls

Abstract

Disclosed is an electroluminescence device having a substrate, a thin film transistor over the substrate, an insulating film over the thin film transistor, an electroluminescence element over the insulating film, a passivation film over the electroluminescence element, and a counter substrate over the passivation film. The electroluminescence element is configured to emit light through the counter substrate, and a space between the substrate and the counter substrate is filled with a filler. The electroluminescence device is featured by the tapered side surface of a gate electrode of the thin film transistor.

Claims

1. A semiconductor device comprising:

a first substrate;

a second substrate over the first substrate, the second substrate being smaller than the first substrate so that the first substrate has a first region which overlaps with the second substrate and a second region which does not overlap with the second substrate;

a pixel portion in the first region, the pixel portion comprising a plurality of pixels between the first substrate and the second substrate;

a wiring over the first substrate, the wiring extending from the first region to the second region;

a flexible printed circuit connected to the wiring in the second region through an anisotropic conductive material;

a filler between the pixel portion and the second substrate, the filler including a drying agent; and

a sealant covering the flexible printed circuit, a part of the second region which does not overlap with the flexible printed circuit, and a side surface of the second substrate,

wherein the plurality of pixels each comprise;

a transistor;

a transparent anode electrically connected to the transistor;

a white-emissive EL layer over the transparent anode, the white-emissive EL layer having a lamination structure of a plurality of layers and being configured to be coupled with a color filter to undergo color display; and

a cathode over the white-emissive EL layer, the cathode comprising aluminum so that light emitted in the white-emissive EL layer is extracted through the first substrate.

2. The semiconductor device according to claim 1,

wherein the transistor further comprises a first terminal and a second terminal and is configured to allow current to flow therebetween, and

wherein the white-emissive EL layer is configured to emit light when the current flows therethrough.

3. The semiconductor device according to claim 2,

wherein the plurality of pixels each further comprise a second wiring configured to supply the current to the white-emissive EL layer through the transistor, and

wherein the second wiring is shared by at least two pixels which neighbor each other.

4. The semiconductor device according to claim 1,

wherein the sealant comprises a resin.

5. The semiconductor device according to claim 1,

wherein the plurality of pixels each further comprise a passivation film over the cathode.

6. The semiconductor device according to claim 5,

wherein the passivation film is a silicon nitride film or a silicon oxynitride film.

7. The semiconductor device according to claim 1,

wherein the semiconductor device is selected from a portable information terminal, a video camera, a still-image camera, a computer, and a television.

8. A semiconductor device comprising:

a first substrate;

a second substrate over the first substrate, the second substrate being smaller than the first substrate so that the first substrate has a first region which overlaps with the second substrate and a second region which does not overlap with the second substrate;

a pixel portion between the first substrate and the second substrate, the pixel portion being located in the first region;

a wiring over the first substrate, the wiring extending from the first region to the second region;

a flexible printed circuit connected to the wiring in the second region through an anisotropic conductive material;

a sealant covering the flexible printed circuit, a part of the second region which does not overlap with the flexible printed circuit, and a side surface of the second substrate;

a plurality of pixels in the pixel portion, the plurality of pixels each comprise;

a transistor;

a transparent anode electrically connected to the transistor;

a white-emissive EL layer over the transparent anode, the white-emissive EL layer having a lamination structure of a plurality of layers and being configured to be coupled with a color filter to undergo color display;

a cathode over the white-emissive EL layer, the cathode comprising aluminum so that light emitted in the white-emissive EL layer is extracted through the first substrate; and

a passivation film over the cathode; and

a filler over and in contact with the passivation film, the filler including a drying agent.

9. The semiconductor device according to claim 8,

wherein the transistor further comprises a first terminal and a second terminal and is configured to allow current to flow therebetween, and

wherein the white-emissive EL layer is configured to emit light when the current flows therethrough.

10. The semiconductor device according to claim 9,

wherein the plurality of pixels each further comprise a second wiring configured to supply the current to the white-emissive EL layer through the transistor, and

wherein the second wiring is shared by at least two pixels which neighbor each other.

11. The semiconductor device according to claim 8,

wherein the sealant comprises a resin.

12. The semiconductor device according to claim 8,

wherein the passivation film is a silicon nitride film or a silicon oxynitride film.

13. The semiconductor device according to claim 8,

wherein the semiconductor device is selected from a portable information terminal, a video camera, a still-image camera, a computer, and a television.

14. A semiconductor device comprising:

a first substrate;

a second substrate over the first substrate, the second substrate being smaller than the first substrate so that the first substrate has a first region which overlaps with the second substrate and a second region which does not overlap with the second substrate;

a pixel portion in the first region, the pixel portion comprising a plurality of pixels between the first substrate and the second substrate;

a wiring over the first substrate, the wiring extending from the first region to the second region;

a flexible printed circuit connected to the wiring in the second region through an anisotropic conductive material;

a filler between the pixel portion and the second substrate, the filler including a drying agent; and

a sealant covering the flexible printed circuit, a part of the second region which does not overlap with the flexible printed circuit, and a side surface of the second substrate,

wherein the plurality of pixels each comprise;

a transistor;

a first insulating film over the transistor;

a transparent anode over the first insulating film, the transparent anode being electrically connected to the transistor;

a second insulating film covering an edge portion of the transparent anode;

a white-emissive EL layer over the transparent anode and the second insulating film, the white-emissive EL layer having a lamination structure of a plurality of layers and being configured to be coupled with a color filter to undergo color display; and

a cathode over the white-emissive EL layer, the cathode comprising aluminum so that light emitted in the white-emissive EL layer is extracted through the first substrate.

15. The semiconductor device according to claim 14,

wherein the transistor further comprises a first terminal and a second terminal and is configured to allow current to flow therebetween, and

wherein the white-emissive EL layer is configured to emit light when the current flows therethrough.

16. The semiconductor device according to claim 15,

wherein the plurality of pixels each further comprise a second wiring configured to supply the current to the white-emissive EL layer through the transistor, and

wherein the second wiring is shared by at least two pixels which neighbor each other.

17. The semiconductor device according to claim 14,

wherein the sealant comprises a resin.

18. The semiconductor device according to claim 14,

wherein the plurality of pixels each further comprise a passivation film over the cathode.

19. The semiconductor device according to claim 18,

wherein the passivation film is a silicon nitride film or a silicon oxynitride film.

20. The semiconductor device according to claim 14,

wherein the semiconductor device is selected from a portable information terminal, a video camera, a still-image camera, a computer, and a television.