Display device and manufacturing method of the same

• US 20060186413A1
• Filed: 09/16/2005
• Published: 08/24/2006
• Est. Priority Date: 10/01/2004
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yamazaki, Shunpei, Sakakura, Masayuki
• Granted Patent: US 8,148,895 B2
• Time in Patent Office: Days
• US Class Current: 257/72
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2300/0861 with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes
• CPC Class Codes: G09G 2310/0251 Precharge or discharge of pixel before applying new pixel voltage
• CPC Class Codes: G09G 2310/0262 The addressing of the pixel, in a display other than an active matrix LCD, involving the control of two or more scan electrodes or two or more data electrodes, e.g. pixel voltage dependent on signals of two data electrodes
• CPC Class Codes: G09G 3/3225 using an active matrix
• CPC Class Codes: G09G 3/3233 with pixel circuitry controlling the current through the light-emitting element
• CPC Class Codes: H01L 27/1218 with a particular composition or structure of the substrate
• 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 29/78603 characterised by the insulating substrate or support H01L29/78657 takes precedence
• CPC Class Codes: H01L 29/78636 with supplementary region or layer for improving the flatness of the device
• CPC Class Codes: H01L 29/78654 Monocrystalline silicon transistors
• CPC Class Codes: H01L 33/0041 characterised by field-effect operation
• CPC Class Codes: H10K 50/8426 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays
• CPC Class Codes: H10K 59/122 Pixel-defining structures or layers, e.g. banks
• CPC Class Codes: H10K 59/123 Connection of the pixel electrodes to the thin film transistors [TFT]
• CPC Class Codes: H10K 59/124 Insulating layers formed between TFT elements and OLED elements
• CPC Class Codes: H10K 71/00 Manufacture or treatment specially adapted for the organic devices covered by this subclass

Abstract

It is an object of the present invention to provide a method for manufacturing a display device in which unevenness generated under a light-emitting element does not impart an adverse effect on the light-emitting element. It is another object of the invention to provide a method for manufacturing a display device in which penetration of water into the inside of the display device through a film having high moisture permeability can be suppressed without increasing processing steps considerably. It is another object of the invention to provide a display device and a method for manufacturing a display device satisfying the above two simultaneously. A display device of the present invention to solve the above problems comprising a thin film transistor and a light-emitting element over an insulating surface formed on a substrate, wherein the light-emitting element includes a light-emitting laminated body interposed between a first electrode and a second electrode; wherein the first electrode is formed over an insulating film formed over the thin film transistor; and wherein a planarizing film is formed in response to the first electrode between the first electrode and the insulating film.

Claims

1. A display device comprising a pixel including a thin film transistor and a light-emitting element over an insulating surface on a substrate,

wherein the light-emitting element includes a first electrode, a second electrode, and a light-emitting laminated body interposed between the first electrode and the second electrode;

wherein the first electrode is formed over an insulating film formed over the thin film transistor; and

wherein a planarizing film for the first electrode is disposed at least between the first electrode and the insulating film.

5. A display device according to claims 1 to 4, wherein the planarizing film is formed only in a region overlapped with the first electrode.

6. A display device according to claims 1 to 4, wherein the planarizing film is formed only in a region overlapped with the first electrode and source and drain electrodes of the thin film transistor.

7. A display device according to claims 1 to 4, wherein the planarizing film is formed from a material having a self-planarizing property.

8. A display device according to claims 1 to 4, wherein the planarizing film is one selected from acrylic, polyimide, and siloxane.

9. A display device according to claims 1 to 4, wherein a P−

V value of the first electrode in the pixel is 30 nm or less.

10. A display device according to claims 1 to 4, wherein a P−

V value of the first electrode in the pixel is 15 nm or less.

11. A display device according to claims 1 to 4, wherein a P−

V value of the first electrode in the pixel is 10 nm or less.

12. A display device according to claim 9, wherein the first electrode has a 10 μ

m square region in which a P−

V value is 30 nm or less.

13. A display device according to claim 10, wherein the first electrode has a 10 μ

m square region in which a P−

V value is 15 nm or less.

14. A display device according to claim 11, wherein the first electrode has a 10 μ

m square region in which a P−

V value is 10 nm or less.

15. A display device according to claims 1 to 4, wherein a buffer layer is formed between the first electrode and the light-emitting laminated body.

16. A display device according to claim 15, wherein, in the case where thickness of the buffer layer is given as d, a P−

V value of the first electrode in the pixel is 30 nm+0.2d nm or less.

17. A display device according to claim 16, wherein, in the case where thickness of the buffer layer is given as d, a P−

V value of the first electrode in the pixel is 15 nm+0.2 d nm or less.

18. A display device according to claim 17, wherein, in the case where thickness of the buffer layer is given as d, a P−

V value of the first electrode in the pixel is 10 nm+0.2d nm or less.

19. A display device according to any one of claims 1 to 4, wherein the insulating film includes an inorganic-based material.

2. A display device comprising a pixel including a thin film transistor and a light-emitting element, and a sealing material surrounding the thin film transistor and the light-emitting element over an insulating surface on a substrate,

wherein the light-emitting element includes a first electrode, a second electrode, and a light-emitting laminated body interposed between the first electrode and the second electrode;

wherein the first electrode is formed over an insulating film formed over the thin film transistor;

wherein a planarizing film for the first electrode is disposed at least between the first electrode and the insulating film; and

wherein the planarizing film is not formed outside the sealing material over the substrate.

3. A display device comprising a pixel including a thin film transistor, a light-emitting element, and a sealing material surrounding the thin film transistor and the light-emitting element over an insulating surface on a substrate,

wherein the light-emitting element includes a first electrode, a second electrode, and a light-emitting laminated body interposed between the first electrode and the second electrode;

wherein the first electrode is formed over an insulating film formed over the thin film transistor;

wherein a planarizing film for the first electrode is disposed at least between the first electrode and the insulating film; and

wherein the insulating film and the sealing material are overlapped with each other.

4. A display device comprising a pixel including a thin film transistor and a light-emitting element, and a sealing material surrounding the thin film transistor and the light-emitting element over an insulating surface on a substrate,

wherein the light-emitting element includes a first electrode, a second electrode, and a light-emitting laminated body interposed between the first electrode and the second electrode;

wherein the first electrode is formed over an insulating film formed over the thin film transistor;

wherein a planarizing film for the first electrode is disposed at least between the first electrode and the insulating film;

wherein the insulating film and the sealing material are overlapped with each other; and

wherein the planarizing film is not formed outside the sealing material over the substrate.

20. A method for manufacturing a light-emitting device, comprising the steps of:

forming a semiconductor film over an insulating surface;

forming a gate insulating film over the semiconductor film;

forming a gate electrode over the gate insulating film;

forming an insulating film over the gate electrode;

forming a contact hole reaching to the semiconductor film by etching the gate insulating film and the insulating film;

forming a conductive film electrically connected to the semiconductor film through the contact hole over the insulating film;

forming a planarizing film covering the insulating film and the conductive film;

exposing at least part of the conductive film by etching the planarizing film;

forming a pixel electrode electrically connected to the conductive film;

removing a region of the planarizing film not covered with the pixel electrode with the use of the pixel electrode as a mask by etching; and

forming a light-emitting element having the pixel electrode as one electrode.

25. A method for manufacturing a light-emitting device according to any one of claims 20 to 24, wherein the planarizing film is formed by an application method.

33. A method for manufacturing a light-emitting device according to any one of claims 20 to 24 and 26 to 29, wherein the first insulating film has a two-layer structure each formed from a different insulating material.

34. A method for manufacturing a light-emitting device according to any one of claims 20 to 24 and 26 to 29, wherein the first insulating film and the gate insulating film are inorganic insulating films.

21. A method for manufacturing a light-emitting device, comprising the steps of:

forming a semiconductor film over an insulating surface;

forming a gate insulating film covering the semiconductor film;

forming a gate electrode over the gate insulating film;

forming an insulating film covering the gate electrode;

forming a planarizing film covering the insulating film;

forming a pixel electrode over the planarizing film;

removing a region of the planarizing film not covered with the pixel electrode with the use of the pixel electrode as a mask by etching;

forming a contact hole reaching to the semiconductor film in the insulating film and the gate insulating film;

forming a wiring electrically connected to the semiconductor film through the contact hole over the insulating film; and

forming a light-emitting element in which part of the wiring is also electrically connected to the pixel electrode and having the pixel electrode as one electrode.

22. A method for manufacturing a light-emitting device, comprising the steps of:

forming a semiconductor film over an insulating surface;

forming a gate insulating film covering the semiconductor film;

forming a gate electrode over the gate insulating film;

forming an insulating film covering the gate electrode;

forming a planarizing film covering the insulating film;

forming a pixel electrode over the planarizing film;

forming a contact hole reaching to the semiconductor film in the planarizing film, the insulating film, and the gate insulating film;

forming a conductive film electrically connected to the semiconductor film through the contact hole over the planarizing film;

removing a region of the planarizing film not covered with the conductive film and the pixel electrode with the use of the conductive film and the pixel electrode as masks by etching; and

forming a light-emitting element in which part of the conductive film is also electrically connected to the pixel electrode and having the pixel electrode as a first electrode.

23. A method for manufacturing a light-emitting device, comprising the steps of:

forming a semiconductor film over an insulating surface;

forming a gate insulating film covering the semiconductor film;

forming a gate electrode over the gate insulating film;

forming an insulating film covering the gate electrode;

forming a planarizing film covering the insulating film;

forming a contact hole reaching to the semiconductor film in the planarizing film, the insulating film, and the gate insulating film;

forming a conductive film electrically connected to the semiconductor film through the contact hole over the planarizing film;

forming a pixel electrode overlapped with at least part of the conductive film over the planarizing film; and

forming a light-emitting element having the pixel electrode as one electrode.

24. A method for manufacturing a light-emitting device, comprising the steps of:

forming a semiconductor film over an insulating surface on a substrate;

forming a gate insulating film over the semiconductor film;

forming a gate electrode over the gate insulating film;

forming a first insulating film over the gate electrode;

forming a contact hole reaching to the semiconductor film by etching the gate insulating film and the first insulating film;

forming a conductive film electrically connected to the semiconductor film through the contact hole over the first insulating film;

forming a planarizing film covering the first insulating film;

exposing at least part of the conductive film by etching the planarizing film;

forming a second insulating film covering the planarizing film and the exposed portion of the conductive film;

forming a contact hole reaching to the conductive film in the second insulating film by forming a mask and etching, and removing the planarizing film in an edge portion of the substrate;

forming a pixel electrode electrically connected to the conductive film through the contact hole; and

forming a light-emitting element having the pixel electrode as one electrode.

26. A method for manufacturing a light-emitting device, comprising the steps of:

forming a semiconductor film over an insulating surface forming a gate insulating film over the semiconductor film;

forming a gate electrode over the gate insulating film;

forming a first insulating film over the gate electrode;

forming a contact hole reaching to the semiconductor film by etching the gate insulating film and the first insulating film;

forming a first conductive film electrically connected to the semiconductor film through the contact hole over the first insulating film;

forming a second insulating film covering the first insulating film and the first conductive film;

forming a contact hole reaching to the first conductive film by etching the second insulating film;

forming a second conductive film electrically connected to the first conductive film;

forming a planarizing film covering the second insulating film and the second conductive film;

exposing at least part of the second conductive film by etching the planarizing film;

forming a third conductive film over the second conductive film and the planarizing film;

forming a mask over the third conductive film;

etching the third conductive film with the use of the mask, and forming a pixel electrode electrically connected to the second conductive film;

removing a region of the planarizing film not covered with the mask and the pixel electrode with the use of the mask and the pixel electrode as masks by etching; and

forming a light-emitting element having the pixel electrode as one electrode.

30. A method for manufacturing a light-emitting device according to any one of claims 26 to 29, wherein the planarizing film is formed by an application method.

31. A method for manufacturing a light-emitting device according to any one of claims 26 to 29, wherein the planarizing film is formed from a material having a self-planarizing property.

32. A method for manufacturing a light-emitting device according to any one of claims 26 to 29, wherein the second insulating film is an inorganic insulating film.

27. A method for manufacturing a light-emitting device, comprising the steps of:

forming a semiconductor film over an insulating surface forming a gate insulating film covering the semiconductor film;

forming a gate electrode over the gate insulating film;

forming a first insulating film covering the gate electrode;

forming a contact hole reaching to the semiconductor film in the first insulating film and the gate insulating film;

forming a first conductive film electrically connected to the semiconductor film through the contact hole over the first insulating film;

forming a second insulating film covering the first insulating film and the first conductive film;

forming a planarizing film covering the second insulating film;

forming a second conductive film over the planarizing film;

forming a mask over the second conductive film;

forming a pixel electrode by etching the second conductive film with the use of the mask;

removing a region of the planarizing film not covered with the mask and the pixel electrode with the use of the mask and the pixel electrode as masks by etching;

forming a contact hole reaching to the first conductive film in the second insulating film;

forming a third conductive film electrically connected to the first conductive film through the contact hole over the second insulating film, part of the third conductive film being also electrically connected to the pixel electrode; and

forming a light-emitting element having the pixel electrode as a first electrode.

28. A method for manufacturing a light-emitting device, comprising the steps of:

forming a semiconductor film over an insulating surface;

forming a gate insulating film covering the semiconductor film;

forming a gate electrode over the gate insulating film;

forming a first insulating film covering the gate electrode;

forming a contact hole reaching to the semiconductor film in the first insulating film and the gate insulating film;

forming a first conductive film electrically connected to the semiconductor film through the contact hole over the first insulating film;

forming a second insulating film covering the first insulating film and the first conductive film;

forming a planarizing film covering the second insulating film;

forming a second conductive film over the planarizing film;

forming a mask over the second conductive film;

forming a pixel electrode by etching the second conductive film with use of the mask;

forming a contact hole reaching to the first conductive film in the planarizing film and the second insulating film;

forming a third conductive film electrically connected to the first conductive film through the contact hole over the planarizing film;

removing a region of the planarizing film not covered With the pixel electrode and the third conductive film with the use of the pixel electrode and the third conductive film as masks; and

forming a light-emitting element having the pixel electrode as a first electrode.

29. A method for manufacturing a light-emitting device, comprising the steps of:

forming a semiconductor film over an insulating surface;

forming a gate insulating film covering the semiconductor film;

forming a gate electrode over the gate insulating film and the semiconductor film;

forming a first insulating film covering the gate insulating film and the gate electrode;

forming a contact hole reaching to the semiconductor film in the first insulating film and the gate insulating film;

forming a first conductive film electrically connected to the semiconductor film through the contact hole over the first insulating film;

forming a second insulating film covering the first insulating film and the first conductive film;

forming a planarizing film covering the second insulating film;

forming a contact hole reaching to the first conductive film in the planarizing film and the second insulating film;

forming a second conductive film electrically connected to the first conductive film through the contact hole over the planarizing film, part of the second conductive film being also electrically connected to the first electrode; and

forming a light-emitting element having the first electrode as a pixel electrode.