Semiconductor device

• US 9,397,149 B2
• Filed: 12/23/2014
• Issued: 07/19/2016
• Est. Priority Date: 12/27/2013
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Takeshima, Koichi, Yamazaki, Shunpei, Suzuki, Kunihiko, Ohno, Masakatsu, Adachi, Hiroki, Idojiri, Satoru
• Primary Examiner(s): TAYLOR, EARL N
• Application Number:
  US14/581,089
• Publication Number:
  US 20150187855A1
• Time in Patent Office: 574 Days
• Field of Search: 257/46, 257/170, 257/496, 257/618, 257/623
• US Class Current: 1/1
• 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 27/1266 the substrate on which the devices are formed not being the final device substrate, e.g. using a temporary substrate
• CPC Class Codes: H01L 29/7869 having a semiconductor body comprising an oxide semiconductor material, e.g. zinc oxide, copper aluminium oxide, cadmium stannate
• CPC Class Codes: H10K 2102/00 Constructional details relating to the organic devices covered by this subclass
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/8426 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 59/1213 the pixel elements being TFTs
• CPC Class Codes: H10K 59/8722 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 71/80 using temporary substrates
• CPC Class Codes: H10K 77/111 Flexible substrates
• CPC Class Codes: Y02E 10/549 Organic PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A display device that includes a first flexible substrate, a first bonding layer over the first flexible substrate, a first insulating film over the first bonding layer, a first element layer over the first insulating film, a second element layer over the first element layer, a second insulating film over the second element layer, a second bonding layer over the second insulating film, and a second flexible substrate over the second bonding layer is provided. The first element layer includes a pixel portion and a circuit portion. The pixel portion includes a display element and a first transistor, and the circuit portion includes a second transistor. The second element layer includes a coloring layer and a light-blocking layer.

Claims

1. A display device comprising:

a first flexible substrate;

a first bonding layer over the first flexible substrate;

a first insulating film over the first bonding layer;

a first element layer over the first insulating film;

a second element layer over the first element layer;

a second insulating film over the second element layer;

a second bonding layer over the second insulating film; and

a second flexible substrate over the second bonding layer,

wherein the first element layer includes a pixel portion and a circuit portion, wherein the pixel portion includes a display element and a first transistor and the circuit portion includes a second transistor,

wherein the second element layer includes a coloring layer and a light-blocking layer,

wherein the first transistor includes;

a first oxide semiconductor layer including a channel formation region; and

a first gate electrode over the first oxide semiconductor layer,

wherein the second transistor includes;

a conductive layer;

a second oxide semiconductor layer over the conductive layer;

a third oxide semiconductor layer over the second oxide semiconductor layer, the third oxide semiconductor layer including a channel formation region;

a fourth oxide semiconductor layer over the third oxide semiconductor layer; and

a second gate electrode over the fourth oxide semiconductor layer, the second gate electrode facing a side surface of the third oxide semiconductor layer, and

wherein the first transistor is a transistor having a single-gate structure.

2. The display device according to claim 1,

wherein each of the first insulating film and the second insulating film includes a silicon oxide film, a silicon oxynitride film, a silicon nitride film, or a silicon nitride oxide film.

3. The display device according to claim 1,

wherein each of the first insulating film and the second insulating film is a film containing nitrogen.

4. The display device according to claim 1,

wherein each of the first oxide semiconductor layer and the second oxide semiconductor layer includes an In-M-Zn oxide, and

wherein the M is Al, Ti, Y, Zr, La, Ce, Nd, or Hf.

5. The display device according to claim 1,

wherein each of the first oxide semiconductor layer and the second oxide semiconductor layer includes an In—

Ga—

Zn oxide.

6. The display device according to claim 1,

wherein the first oxide semiconductor layer includes a crystal part whose c-axis is perpendicular to a top surface of the first oxide semiconductor layer,

wherein the first oxide semiconductor layer is a non-single-crystal oxide semiconductor layer,

wherein the second oxide semiconductor layer includes a crystal part whose c-axis is perpendicular to a top surface of the second oxide semiconductor layer, and

wherein the second oxide semiconductor layer is a non-single-crystal oxide semiconductor layer.

7. The display device according to claim 1,

wherein the first oxide semiconductor layer is a single layer, and

wherein the second oxide semiconductor layer is a multilayer.

8. The display device according to claim 7,

wherein the first oxide semiconductor layer has the same composition as a layer of the multilayer, the layer being in contact with a gate insulating film of the second oxide semiconductor layer.

9. The display device according to claim 1,

wherein the display element is an organic EL element.

10. A display device comprising:

a first flexible substrate;

a first bonding layer over the first flexible substrate;

a first insulating film over the first bonding layer;

a first element layer over the first insulating film;

a second element layer over the first element layer;

a second insulating film over the second element layer;

a second bonding layer over the second insulating film; and

a second flexible substrate over the second bonding layer,

wherein the first element layer includes a pixel portion and a circuit portion, wherein the pixel portion includes a display element and a first transistor and the circuit portion includes a second transistor,

wherein the second element layer includes a coloring layer and a light-blocking layer,

wherein the first transistor includes;

a first oxide semiconductor layer including a channel formation region; and

a first gate electrode over the first oxide semiconductor layer,

wherein the second transistor includes;

a conductive layer;

a second oxide semiconductor layer over the conductive layer;

a third oxide semiconductor layer over the second oxide semiconductor layer, the third oxide semiconductor layer including a channel formation region;

a fourth oxide semiconductor layer over the third oxide semiconductor layer; and

a second gate electrode over the fourth oxide semiconductor layer, the second gate electrode facing a side surface of the third oxide semiconductor layer,

wherein the first transistor is a transistor having a single-gate structure, and

wherein an insulating layer is in contact with a top surface of the first oxide semiconductor layer.

11. The display device according to claim 10,

wherein each of the first insulating film and the second insulating film includes a silicon oxide film, a silicon oxynitride film, a silicon nitride film, or a silicon nitride oxide film.

12. The display device according to claim 10,

wherein each of the first insulating film and the second insulating film is a film containing nitrogen.

13. The display device according to claim 10,

wherein each of the first oxide semiconductor layer and the second oxide semiconductor layer includes an In-M-Zn oxide, and

wherein the M is Al, Ti, Y, Zr, La, Ce, Nd, or Hf.

14. The display device according to claim 10,

wherein each of the first oxide semiconductor layer and the second oxide semiconductor layer includes an In—

Ga—

Zn oxide.

15. The display device according to claim 10,

wherein the first oxide semiconductor layer includes a crystal part whose c-axis is perpendicular to a top surface of the first oxide semiconductor layer,

wherein the first oxide semiconductor layer is a non-single-crystal oxide semiconductor layer,

wherein the second oxide semiconductor layer includes a crystal part whose c-axis is perpendicular to a top surface of the second oxide semiconductor layer, and

wherein the second oxide semiconductor layer is a non-single-crystal oxide semiconductor layer.

16. The display device according to claim 10,

wherein the first oxide semiconductor layer is a single layer, and

wherein the second oxide semiconductor layer is a multilayer.

17. The display device according to claim 16,

wherein the first oxide semiconductor layer has the same composition as a layer of the multilayer, the layer being in contact with a gate insulating film of the second oxide semiconductor layer.

18. The display device according to claim 10,

wherein the display element is an organic EL element.

19. A display device comprising:

a first flexible substrate;

a first bonding layer over the first flexible substrate;

a first insulating film over the first bonding layer;

a first element layer over the first insulating film;

a second element layer over the first element layer; and

a second insulating film over the second element layer,

wherein the first element layer includes a pixel portion and a circuit portion, wherein the pixel portion includes a display element and a first transistor and the circuit portion includes a second transistor,

wherein the second element layer includes a coloring layer and a light-blocking layer,

wherein the first transistor includes;

a first oxide semiconductor layer including a channel formation region; and

a first gate electrode overlapping with the first oxide semiconductor layer, and

wherein the second transistor includes;

a conductive laver;

a second oxide semiconductor layer over the conductive layer;

a third oxide semiconductor layer over the second oxide semiconductor layer, the third oxide semiconductor layer including a channel formation region;

a fourth oxide semiconductor layer over the third oxide semiconductor layer; and

a second gate electrode over the fourth oxide semiconductor layer, and

wherein the first transistor is a transistor having a single-gate structure.

20. The display device according to claim 19,

wherein each of the first insulating film and the second insulating film includes a silicon oxide film, a silicon oxynitride film, a silicon nitride film, or a silicon nitride oxide film.

21. The display device according to claim 19,

wherein each of the first insulating film and the second insulating film is a film containing nitrogen.

22. The display device according to claim 19,

wherein each of the first oxide semiconductor layer and the second oxide semiconductor layer includes an In—

Ga—

Zn oxide.

23. A semiconductor device comprising:

a first transistor including;

a first oxide semiconductor layer over an insulating surface; and

a first gate electrode overlapping with the first oxide semiconductor layer; and

a second transistor including;

a second oxide semiconductor layer over the insulating surface;

a third oxide semiconductor layer over the second oxide semiconductor layer;

a fourth oxide semiconductor layer over the third oxide semiconductor layer; and

a second gate electrode overlapping with the second oxide semiconductor layer, the third oxide semiconductor layer, and the fourth oxide semiconductor layer,

wherein the first oxide semiconductor layer and the fourth oxide semiconductor layer comprises a same material,

wherein indium content in the third oxide semiconductor layer is higher than indium content in the fourth oxide semiconductor layer and higher than indium content in the first oxide semiconductor layer, and

wherein a channel formation region of the first oxide semiconductor layer is in contact with the insulating surface, the channel formation region overlapping with the first gate electrode.

24. The semiconductor device according to claim 23, wherein the first oxide semiconductor layer and the fourth oxide semiconductor layer are formed from a same oxide semiconductor layer.

25. The semiconductor device according to claim 23, further comprising:

a flexible substrate;

a bonding layer over the flexible substrate;

an insulating film over the bonding layer,

wherein the first oxide semiconductor layer and the second oxide semiconductor layer are located over the insulating film.

26. The semiconductor device according to claim 23,

wherein a pixel portion comprises the first transistor, and

wherein a driver circuit portion comprises the second transistor.