Semiconductor device and method of manufacturing the same

• US 7,888,714 B2
• Filed: 09/15/2005
• Issued: 02/15/2011
• Est. Priority Date: 10/04/2004
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Maruyama, Junya, Adachi, Hiroki, Yamada, Daiki, Nishi, Kazuo, Sugawara, Yuusuke, Kusumoto, Naoto, Takahashi, Hidekazu
• Primary Examiner(s): Shingleton; Michael B
• Application Number:
  US11/226,472
• Publication Number:
  US 20070187790A1
• Time in Patent Office: 1,979 Days
• Field of Search: 257/291, 257/292, 257/458, 257/459, 257/E27.132, 257/E27.133
• US Class Current: 257/291
• 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 27/14609 Pixel-elements with integrated switching, control, storage or amplification elements scanning details of imagers (circuitry of solid-state image sensors H04N25/00); circuitry of imagers H04N25/70
• CPC Class Codes: H01L 27/14645 Colour imagers
• CPC Class Codes: H01L 27/14692 Thin film technologies, e.g. amorphous, poly, micro- or nanocrystalline silicon

Abstract

Considering further promotion of high output and miniaturization of a sensor element, it is an object of the present invention to form a plurality of elements in a limited area so that an area occupied by the element is reduced for integration. It is another object to provide a process which improves the yield of a sensor element. According to the present invention, a sensor element using an amorphous silicon film and an output amplifier circuit constituted by a thin film transistor are formed over a substrate having an insulating surface. In addition, a metal layer for protecting an exposed wire when a photoelectric conversion layer of the sensor element is patterned is provided between the photoelectric conversion layer and the wire connected to the thin film transistor.

Claims

1. A semiconductor device comprising:

a substrate having an insulating surface;

a light sensor element over the insulating surface, the light sensor element comprising a first electrode, a second electrode, and a photoelectric conversion layer;

a wire electrically connected to the first electrode; and

an amplifier circuit including an n-channel TFT, the amplifier circuit over the insulating surface,

wherein the n-channel TFT includes a source electrode, a drain electrode, and a gate electrode,

wherein the gate electrode of the n-channel TFT is electrically connected to the wire,

wherein the wire is covered with the first electrode,

wherein the second electrode is provided over the photoelectric conversion layer,

wherein end portions of the second electrode extend beyond end portions of the photoelectric conversion layer, and

wherein the first electrode is a film containing Ti.

5. The semiconductor device according to claim 1,

wherein the photoelectric conversion layer comprises a p-type crystalline semiconductor layer, and

wherein the film containing Ti is in contact with the p-type crystalline semiconductor layer.

7. The semiconductor device according to claim 1, wherein the wire has a three-layer structure of a first film containing Ti, a film containing aluminum, and a second film containing Ti.

11. The semiconductor device according to claim 1, wherein the second electrode is a conductive material containing a resin.

15. The semiconductor device according to claim 1, wherein the second electrode partially overlaps the first electrode and the wire.

19. The semiconductor device according to claim 1, wherein the substrate is a glass substrate.

23. The semiconductor device according to claim 1, wherein the substrate is a plastic substrate.

27. The semiconductor device according to claim 1, wherein an external terminal provided over the substrate has a two-terminal structure.

31. The semiconductor device according to claim 1, wherein the semiconductor device is selected from the group consisting of a video camera, a digital camera, a personal computer, and a portable information terminal.

2. A semiconductor device comprising:

a substrate having an insulating surface;

a light sensor element over the insulating surface, the light sensor element comprising a first electrode, a second electrode, and a photoelectric conversion layer;

a wire electrically connected to the first electrode; and

an amplifier circuit including a TFT, the amplifier circuit over the insulating surface,

wherein the TFT includes a source electrode, a drain electrode, and a gate electrode,

wherein the gate electrode of the TFT is electrically connected to the wire,

wherein the wire is covered with the first electrode,

wherein the second electrode is provided over the photoelectric conversion layer,

wherein end portions of a top surface of the second electrode extend beyond end portions of the photoelectric conversion layer, and

wherein the first electrode is a film containing Ti.

6. The semiconductor device according to claim 2,

wherein the photoelectric conversion layer comprises a P-type crystalline semiconductor layer, and

wherein the film containing Ti is in contact with the p-type crystalline semiconductor layer.

8. The semiconductor device according to claim 2, wherein the wire has a three-layer structure of a first film containing Ti, a film containing aluminum, and a second film containing Ti.

12. The semiconductor device according to claim 2, wherein the second electrode is a conductive material containing a resin.

16. The semiconductor device according to claim 2, wherein the second electrode partially overlaps the first electrode and the wire.

20. The semiconductor device according to claim 2, wherein the substrate is a glass substrate.

24. The semiconductor device according to claim 2, wherein the substrate is a plastic substrate.

28. The semiconductor device according to claim 2, wherein an external terminal provided over the substrate has a two-terminal structure.

32. The semiconductor device according to claim 2, wherein the semiconductor device is selected from the group consisting of a video camera, a digital camera, a personal computer, and a portable information terminal.

3. A semiconductor device comprising:

a substrate having an insulating surface;

a light sensor element over the insulating surface; and

an amplifier circuit over the insulating surface,

wherein the amplifier circuit comprises an n-channel TFT having a semiconductor film having a crystalline structure, and

wherein the light sensor element includes a wire connected to the n-channel TFT, a photoelectric conversion layer over the wire, and an electrode on the photoelectric conversion layer, and an end portion of the electrode projects beyond an end portion of the photoelectric conversion layer.

9. The semiconductor device according to claim 3, wherein the wire has a three-layer structure of a first film containing Ti, a film containing aluminum, and a second film containing Ti.

13. The semiconductor device according to claim 3, wherein the electrode is a conductive material containing a resin.

17. The semiconductor device according to claim 3, wherein the electrode partially overlaps the wire.

21. The semiconductor device according to claim 3, wherein the substrate is a glass substrate.

25. The semiconductor device according to claim 3, wherein the substrate is a plastic substrate.

29. The semiconductor device according to claim 3, wherein an external terminal provided over the substrate has a two-terminal structure.

33. The semiconductor device according to claim 3, wherein the semiconductor device is selected from the group consisting of a video camera, a digital camera, a personal computer, and a portable information terminal.

4. A semiconductor device comprising:

a small piece of a substrate having an insulating surface;

a light sensor element over the insulating surface; and

an amplifier circuit over the insulating surface,

an interlayer insulating film over the thin film transistor;

a wire connected to the thin film transistor over the interlayer insulating film;

a photoelectric conversion layer formed over a part of the wire; and

an electrode over the photoelectric conversion layer,

wherein an end portion of the electrode projects than an end portion of the photoelectric conversion layer.

10. The semiconductor device according to claim 4, wherein the wire has a three-layer structure of a first film containing Ti, a film containing aluminum, and a second film containing Ti.

14. The semiconductor device according to claim 4, wherein the electrode is a conductive material containing a resin.

18. The semiconductor device according to claim 4, wherein the electrode partially overlaps the wire.

22. The semiconductor device according to claim 4, wherein the substrate is a glass substrate.

26. The semiconductor device according to claim 4, wherein the substrate is a plastic substrate.

30. The semiconductor device according to claim 4, wherein an external terminal provided over the substrate has a two-terminal structure.

34. The semiconductor device according to claim 4, wherein the semiconductor device is selected from the group consisting of a video camera, a digital camera, a personal computer, and a portable information terminal.