Electro-optical device and electronic device

• US 20050161672A1
• Filed: 03/09/2005
• Published: 07/28/2005
• Est. Priority Date: 06/04/1999
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamamoto, Kunitaka, Konuma, Toshimitsu, Koyama, Jun, Yamazaki, Shunpei
• Granted Patent: US 7,701,134 B2
• Time in Patent Office: Days
• US Class Current: 257/59
• CPC Class Codes: H01L 27/1218 with a particular composition or structure of the substrate
• CPC Class Codes: H01L 27/1255 integrated with passive devices, e.g. auxiliary capacitors
• 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 29/78621 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 29/78645 with multiple gate
• CPC Class Codes: H01L 29/78696 characterised by the structure of the channel, e.g. multichannel, transverse or longitudinal shape, length or width, doping structure, or the overlap or alignment between the channel and the gate, the source or the drain, or the contacting structure of the channel H01L29/78612 takes precedence; transistors having a drain offset region or a lightly doped drain [LDD] H01L29/78621
• 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: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 50/84 Passivation; Containers; Encapsulations
• CPC Class Codes: H10K 50/841 Self-supporting sealing arrangements
• CPC Class Codes: H10K 50/8426 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 50/846 comprising getter material or desiccants
• CPC Class Codes: H10K 50/87 Arrangements for heating or cooling
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/1213 the pixel elements being TFTs
• CPC Class Codes: H10K 59/123 Connection of the pixel electrodes to the thin film transistors [TFT]
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]

Abstract

An object of the present invention is to provide an EL display device having a high operation performance and reliability.

The switching TFT 201 formed within a pixel has a multi-gate structure, which is a structure which imposes an importance on reduction of OFF current value. Further, the current control TFT 202 has a channel width wider than that of the switching TFT to make a structure appropriate for flowing electric current. Morever, the LDD region 33 of the current control TFT 202 is formed so as to overlap a portion of the gate electrode 35 to make a structure which imposes importance on prevention of hot carrier injection and reduction of OFF current value.

Claims

1. A display device comprising:

a pixel portion comprising a first thin film transistor and a driving circuit comprising a second thin film transistor over a substrate;

a first electrode over the first transistor;

a light emitting layer comprising an organic material formed over the first electrode;

a second electrode over the light emitting layer comprising the organic material; and

a housing material opposed to the first substrate by an adhesive, thereby, forming an airtight space between the substrate and the housing material,

wherein the pixel portion and at least a part of the driving circuit are located in a region surrounded by the adhesive.

2. The display device according to claim 1,

wherein the first thin film transistor comprises an active layer in which two or more channel regions connected in series are formed.

3. The display device according to claim 1,

wherein the display device is used as a display for one selected from the group consisting of a video camera, a digital camera, a goggle type display, a car navigation system, a personal computer, a portable information terminal and an image playback device using a recording medium.

4. A display device comprising:

a pixel portion comprising a first thin film transistor and a driving circuit comprising a second thin film transistor over a substrate;

a first electrode over the first transistor;

a light emitting layer comprising an organic material formed over the first electrode;

a second electrode over the light emitting layer comprising the organic material; and

a glass opposed to the first substrate by an adhesive, thereby, forming an airtight space between the substrate and the glass,

wherein the pixel portion and at least a part of the driving circuit are located in a region surrounded by the adhesive.

5. The display device according to claim 4,

wherein the first thin film transistor comprises an active layer in which two or more channel regions connected in series are formed.

6. The display device according to claim 4,

wherein the display device is used as a display for one selected from the group consisting of a video camera, a digital camera, a goggle type display, a car navigation system, a personal computer, a portable information terminal and an image playback device using a recording medium.

7. A display device comprising:

a pixel portion comprising a first thin film transistor and a driving circuit comprising a second thin film transistor over a substrate;

a first electrode over the first transistor;

a light emitting layer comprising an organic material formed over the first electrode;

a second electrode over the light emitting layer comprising the organic material; and

a housing material opposed to the first substrate by epoxy resin, thereby, forming an airtight space between the substrate and the housing material,

wherein the pixel portion and at least a part of the driving circuit are located in a region surrounded by the epoxy resin.

8. The display device according to claim 7,

wherein the first thin film transistor comprises an active layer in which two or more channel regions connected in series are formed.

9. The display device according to claim 7,

wherein the display device is used as a display for one selected from the group consisting of a video camera, a digital camera, a goggle type display, a car navigation system, a personal computer, a portable information terminal and an image playback device using a recording medium.

10. A display device comprising:

a pixel portion comprising a first thin film transistor and a driving circuit comprising a second thin film transistor over a substrate;

a first electrode over the first transistor;

a light emitting layer comprising an organic material formed over the first electrode;

a second electrode over the light emitting layer comprising the organic material; and

a housing material opposed to the first substrate by an adhesive, thereby, forming an airtight space filled with an inert gas between the substrate and the housing material,

wherein the pixel portion and at least a part of the driving circuit are located in a region surrounded by the adhesive.

11. The display device according to claim 10,

wherein the first thin film transistor comprises an active layer in which two or more channel regions connected in series are formed.

12. The display device according to claim 10,

wherein the display device is used as a display for one selected from the group consisting of a video camera, a digital camera, a goggle type display, a car navigation system, a personal computer, a portable information terminal and an image playback device using a recording medium.

13. A display device comprising:

a pixel portion comprising a first thin film transistor and a driving circuit comprising a second thin film transistor over a substrate;

a first electrode over the first transistor;

a light emitting layer comprising an organic material formed over the first electrode;

a second electrode over the light emitting layer comprising the organic material; and

a housing material opposed to the first substrate by an adhesive, thereby, forming an airtight space filled with an inert liquid between the substrate and the housing material,

wherein the pixel portion and at least a part of the driving circuit are located in a region surrounded by the adhesive.

14. The display device according to claim 13,

wherein the first thin film transistor comprises an active layer in which two or more channel regions connected in series are formed.

15. The display device according to claim 13,

wherein the display device is used as a display for one selected from the group consisting of a video camera, a digital camera, a goggle type display, a car navigation system, a personal computer, a portable information terminal and an image playback device using a recording medium.

16. A display device comprising:

a pixel portion comprising a first thin film transistor and a driving circuit comprising a second thin film transistor over a substrate;

a first electrode over the first transistor;

a light emitting layer comprising an organic material formed over the first electrode;

a second electrode over the light emitting layer comprising the organic material; and

a housing material opposed to the first substrate by an adhesive, thereby, forming an airtight space between the substrate and the housing material,

wherein the pixel portion and at least a part of the driving circuit are located in a region surrounded by the adhesive, and

wherein drying agent is provided in the airtight space.

17. The display device according to claim 16,

wherein the first thin film transistor comprises an active layer in which two or more channel regions connected in series are formed.

18. The display device according to claim 16,

wherein the display device is used as a display for one selected from the group consisting of a video camera, a digital camera, a goggle type display, a car navigation system, a personal computer, a portable information terminal and an image playback device using a recording medium.