Method of making a thin film transistor device

• US 7,405,132 B2
• Filed: 10/03/2005
• Issued: 07/29/2008
• Est. Priority Date: 09/06/2000
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Isobe, Atsuo, Takayama, Toru, Arao, Tatsuya
• Primary Examiner(s): Hu; Shouxiang
• Application Number:
  US11/242,234
• Publication Number:
  US 20060071215A1
• Time in Patent Office: 1,030 Days
• Field of Search: 438/149, 438/151, 438/28, 438/30, 438/155, 438/393
• US Class Current: 438/393
• CPC Class Codes: G02F 1/133305 Flexible substrates, e.g. plastics, organic film
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: G02F 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer
• CPC Class Codes: G02F 1/136295 Materials; Compositions; Manufacture processes
• 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 27/1255 integrated with passive devices, e.g. auxiliary capacitors
• CPC Class Codes: H01L 29/66742 Thin film unipolar transistors
• CPC Class Codes: H01L 29/78603 characterised by the insulating substrate or support H01L29/78657 takes precedence
• CPC Class Codes: H10K 59/12 Active-matrix OLED [AMOLED] displays

Abstract

In a semiconductor device having a substrate which has a metal surface, an insulating film which is formed on the substrate having the metal surface, and a pixel unit which is formed on the insulating film; the pixel unit includes a TFT, and wiring lines connected with the TFT, and a storage capacitor is constituted by the substrate (11) having the metal surface, the insulating film (12), and the wiring line (21). As the insulating film is thinner, and as the area of a region where the insulating film and the wiring line lie in contact is larger, the storage capacitor is endowed with a larger capacity.

Claims

1. A method of manufacturing a semiconductor device comprising:

forming a first insulating film over a metal substrate;

forming a semiconductor layer over the first insulating film;

forming a second insulating film over the semiconductor layer and the first insulating film;

forming a gate electrode over the second insulating film;

removing a portion of the second insulating film, so as to expose a portion of the first insulating film;

forming a third insulating film over the gate electrode and the second insulating film and contacting the portion of the first insulating film;

partly removing the third insulating film so as to expose the portion of the first insulating film; and

forming a wiring line electrically connected to the semiconductor layer and in contact with the portion of said first insulating film,

wherein a storage capacitor is formed of the metal substrate and the wiring line, with the portion of the first insulating film therebetween.

2. A method of manufacturing a semiconductor device according to claim 1, wherein a surface of the metal substrate has a roughness of at most 1 μ

mRMAX.

3. A method of manufacturing a semiconductor device according to claim 1, wherein a radius of curvature of a convex part which exists in a surface of the metal substrate is at least 1 μ

m.

4. A method of manufacturing a semiconductor device according to claim 1, wherein the metal substrate is a stainless substrate or a substrate formed with a conductive film.

5. A method of manufacturing a semiconductor device according to claim 1, wherein the semiconductor device is a liquid crystal display device.

6. A method of manufacturing a semiconductor device according to claim 1, wherein the semiconductor device is an electronic equipment selected from the group consisting of a display, a portable telephone, a video camera, a digital camera, a goggle type display, a car navigation system, a car stereo, a personal computer, a DVD player, an electronic book, and a portable information terminal.

7. A method of manufacturing a semiconductor device according to claim 1, wherein the third insulating film has an uneven surface.

8. A method of manufacturing a semiconductor device according to claim 1, wherein the second insulating film is a gate insulating film.

9. A method of manufacturing a semiconductor device comprising:

forming a first insulating film over a metal substrate;

forming a semiconductor layer over the first insulating film;

forming a second insulating film over the semiconductor layer and the first insulating film;

forming a gate electrode over the second insulating film;

removing a portion of the second insulating film, so as to expose a portion of the first insulating film;

forming a third insulating film over the semiconductor layer and the second insulating film and contacting the portion of the first insulating film;

partly removing the third insulating film so as to expose the portion of the first insulating film;

forming a contact hole in the third insulating film; and

forming a wiring line electrically connected to the semiconductor layer through the contact hole and in contact with the portion of said first insulating film,

wherein a storage capacitor is formed of the metal substrate and the wiring line, with the portion of the first insulating film therebetween.

10. A method of manufacturing a semiconductor device according to claim 9, wherein a surface of the metal substrate has a roughness of at most 1 μ

mRMAX.

11. A method of manufacturing a semiconductor device according to claim 9, wherein a radius of curvature of a convex part which exists in a surface of the metal substrate is at least 1 μ

m.

12. A method of manufacturing a semiconductor device according to claim 9, wherein the metal substrate is a stainless substrate or a substrate formed with a conductive film.

13. A method of manufacturing a semiconductor device according to claim 9, wherein the semiconductor device is a liquid crystal display device.

14. A method of manufacturing a semiconductor device according to claim 9, wherein the semiconductor device is an electronic equipment selected from the group consisting of a display, a portable telephone, a video camera, a digital camera, a goggle type display, a car navigation system, a car stereo, a personal computer, a DVD player, an electronic book, and a portable information terminal.

15. A method of manufacturing a semiconductor device according to claim 9, wherein the third insulating film has an uneven surface.

16. A method of manufacturing a semiconductor device according to claim 9, wherein the second insulating film is a gate insulating film.

17. A method of manufacturing a semiconductor device according to claim 9, wherein partly removing the third insulating film and forming the contact hole are performed at the same time.

18. A method of manufacturing a semiconductor device comprising:

forming a first insulating film over a metal substrate;

forming a semiconductor layer over the first insulating film;

forming a second insulating film over the semiconductor layer and the first insulating film;

forming a gate electrode over the second insulating film;

removing a portion of the second insulating film, so as to expose a portion of the first insulating film;

forming a third insulating film over the gate electrode and the second insulating film and contacting the portion of the first insulating film;

partly removing the third insulating film so as to expose the portion of the first insulating film;

forming a first wiring line electrically connected to the semiconductor layer and in contact with the portion of said first insulating film,

forming a fourth insulating film over the first wiring line;

partly removing the fourth insulating film so as to expose a portion of the first wiring line; and

forming a second wiring line electrically connected to the first wiring line,

wherein a storage capacitor is formed of the metal substrate and the first wiring line, with the portion of the first insulating film therebetween.

19. A method of manufacturing a semiconductor device according to claim 18, wherein a surface of the metal substrate has a roughness of at most 1 μ

mRMAX.

20. A method of manufacturing a semiconductor device according to claim 18, wherein a radius of curvature of a convex part which exists in a surface of the metal substrate is at least 1 μ

m.

21. A method of manufacturing a semiconductor device according to claim 18, wherein the metal substrate is a stainless substrate or a substrate formed with a conductive film.

22. A method of manufacturing a semiconductor device according to claim 18, wherein the semiconductor device is a liquid crystal display device.

23. A method of manufacturing a semiconductor device according to claim 18, wherein the semiconductor device is an electronic equipment selected from the group consisting of a display, a portable telephone, a video camera, a digital camera, a goggle type display, a car navigation system, a car stereo, a personal computer, a DVD player, an electronic book, and a portable information terminal.

24. A method of manufacturing a semiconductor device according to claim 18, wherein the third insulating film has an uneven surface.

25. A method of manufacturing a semiconductor device according to claim 18, wherein the second insulating film is a gate insulating film.

26. A method of manufacturing a semiconductor device comprising:

forming a first insulating film over a metal substrate;

forming a semiconductor layer over the first insulating film;

forming a second insulating film over the semiconductor layer and the first insulating film;

forming a gate electrode over the second insulating film;

removing a portion of the second insulating film, so as to expose a portion of the first insulating film;

forming a third insulating film over the gate electrode and the second insulating film and contacting the portion of the first insulating film;

partly removing the third insulating film so as to expose the portion of the first insulating film;

forming a contact hole in the third insulating film; and

forming a first wiring line electrically connected to the semiconductor layer through the contact hole and in contact with the portion of said first insulating film;

forming a fourth insulating film over the first wiring line;

partly removing the fourth insulating film so as to expose a portion of the first wiring line; and

forming a second wiring line electrically connected to the first wiring line,

wherein a storage capacitor is formed of the metal substrate and the first wiring line, with the portion of the first insulating film therebetween.

27. A method of manufacturing a semiconductor device according to claim 26, wherein a surface of the metal substrate has a roughness of at most 1 μ

mRMAX.

28. A method of manufacturing a semiconductor device according to claim 26, wherein a radius of curvature of a convex part which exists in a surface of the metal substrate is at least 1 μ

m.

29. A method of manufacturing a semiconductor device according to claim 26, wherein the metal substrate is a stainless substrate or a substrate formed with a conductive film.

30. A method of manufacturing a semiconductor device according to claim 26, wherein the semiconductor device is a liquid crystal display device.

31. A method of manufacturing a semiconductor device according to claim 26, wherein the semiconductor device is an electronic equipment selected from the group consisting of a display, a portable telephone, a video camera, a digital camera, a goggle type display, a car navigation system, a car stereo, a personal computer, a DVD player, an electronic book, and a portable information terminal.

32. A method of manufacturing a semiconductor device according to claim 26, wherein the third insulating film has an uneven surface.

33. A method of manufacturing a semiconductor device according to claim 26, wherein the second insulating film is a gate insulating film.

34. A method of manufacturing a semiconductor device according to claim 26, wherein partly removing the third insulating film and forming the contact hole are performed at the same time.