Area sensor and display apparatus provided with an area sensor

• US 7,030,551 B2
• Filed: 08/08/2001
• Issued: 04/18/2006
• Est. Priority Date: 08/10/2000
• Status: Expired due to Fees

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Yonezawa, Masato, Kimura, Hajime, Koyama, Jun, Yamazaki, Shunpei, Yamazaki, Yu
• Primary Examiner(s): Santiago, Mariceli
• Application Number:
  US09/924,108
• Publication Number:
  US 20020044208A1
• Time in Patent Office: 1,714 Days
• Field of Search: 313/498, 257/E27.141, 257/E25.112, 257/52, 257/53, 257/E31.095, 257/E31.096
• US Class Current: 313/498
• CPC Class Codes: G09G 2300/0809 Several active elements per pixel in active matrix panels
• CPC Class Codes: G09G 2310/0286 Details of a shift registers arranged for use in a driving circuit
• CPC Class Codes: G09G 2310/0291 Details of output amplifiers or buffers arranged for use in a driving circuit
• CPC Class Codes: G09G 2320/0646 Modulation of illumination source brightness and image signal correlated to each other
• CPC Class Codes: G09G 3/3258 with pixel circuitry controlling the voltage across the light-emitting element
• CPC Class Codes: G09G 3/3266 Details of drivers for scan electrodes
• CPC Class Codes: H01L 27/14623 Optical shielding
• CPC Class Codes: H01L 27/14632 Wafer-level processed structures
• CPC Class Codes: H01L 27/14643 Photodiode arrays; MOS imagers
• CPC Class Codes: H01L 27/14678 Contact-type imagers
• CPC Class Codes: H01L 27/14687 Wafer level processing
• CPC Class Codes: H01L 27/14692 Thin film technologies, e.g. amorphous, poly, micro- or nanocrystalline silicon
• CPC Class Codes: H01L 27/15 including semiconductor components having potential barriers, specially adapted for light emission
• CPC Class Codes: H01L 29/78672 Polycrystalline or microcrystalline silicon transistor
• CPC Class Codes: H04N 25/447 by preserving the colour pattern with or without loss of information
• CPC Class Codes: H04N 25/76 Addressed sensors, e.g. MOS or CMOS sensors
• CPC Class Codes: H04N 3/155 Control of the image-sensor operation, e.g. image processing within the image-sensor
• CPC Class Codes: H10K 2102/311 Flexible OLED
• 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 59/1216 : the pixel elements being capacitors
• 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 59/13 : comprising photosensors that control luminance
• CPC Class Codes: H10K 59/131 : Interconnections, e.g. wiring lines or terminals
• CPC Class Codes: H10K 59/40 : OLEDs integrated with touch screens
• CPC Class Codes: H10K 59/65 : OLEDs integrated with inorganic image sensors
• CPC Class Codes: H10K 77/111 : Flexible substrates
• CPC Class Codes: Y02E 10/549 : Organic PV cells

Abstract

An area sensor of the present invention has a function of displaying an image in a sensor portion by using light-emitting elements and a reading function using photoelectric conversion devices. Therefore, an image read in the sensor portion can be displayed thereon without separately providing an electronic display on the area sensor. Furthermore, a photoelectric conversion layer of a photodiode according to the present invention is made of an amorphous silicon film and an N-type semiconductor layer and a P-type semiconductor layer are made of a polycrystalline silicon film. The amorphous silicon film is formed to be thicker than the polycrystalline silicon film. As a result, the photodiode according to the present invention can receive more light.

Claims

1. An area sensor comprising a sensor portion, the sensor portion comprising:

a plurality of pixels, each of the plurality of pixels comprising a photodiode, an electroluminescence element and a plurality of thin film transistors,

wherein;

the photodiode includes a photoelectric conversion layer that is in contact with a part of a P-type semiconductor layer and an N-type semiconductor layer,

the photoelectric conversion layer is made of an amorphous semiconductor film, and

the photoelectric conversion layer is thicker than the P-type semiconductor layer and the N-type semiconductor layer.

2. An area sensor according to claim 1, wherein the N-type semiconductor layer comprises polysilicon.

3. An area sensor according to claim 1, wherein the P-type semiconductor layer comprises polysilicon.

4. An area sensor according to claim 1, wherein the photoelectric conversion layer comprises amorphous silicon.

5. An area sensor according to claim 1, wherein the electroluminescence element has a positive electrode, a negative electrode and an electroluminescence layer provided between the positive electrode and the negative electrode.

6. An area sensor according to claim 1, wherein the area sensor is included in electronic equipment selected from the group of:

a video camera, a digital still camera, a notebook computer and a portable information terminal.

7. An area sensor comprising a sensor portion, the sensor portion comprising:

a plurality of pixels, each of the plurality of pixels comprising a photodiode, an electroluminescence element and a plurality of thin film transistors,

wherein;

light emitted from the electroluminescence element is reflected from a subject to be radiated to the photodiode,

the photodiode generates an image signal from the light reflected to the photodiode,

the photodiode includes a photoelectric conversion layer that is in contact with a part of a P-type semiconductor layer an N-type semiconductor layer,

the photoelectric conversion layer is made of an amorphous semiconductor film, and

the photoelectric conversion layer is thicker than the P-type semiconductor layer and the N-type semiconductor layer.

8. An area sensor according to claim 7, wherein the N-type semiconductor layer comprises polysilicon.

9. An area sensor according to claim 7, wherein the P-type semiconductor layer comprises polysilicon.

10. An area sensor according to claim 7, wherein the photoelectric conversion layer comprises amorphous silicon.

11. An area sensor according to claim 7, wherein the electroluminescence element has a positive electrode, a negative electrode and an electroluminescence layer provided between the positive electrode and the negative electrode.

12. An area sensor according to claim 7, wherein the area sensor is included in electronic equipment selected from the group of:

a video camera, a digital still camera, a notebook computer and a portable information terminal.

13. An area sensor comprising a sensor portion, the sensor portion comprising:

a plurality of pixels, each of the plurality of pixels comprising a photodiode, an electroluminescence element and a plurality of thin film transistors,

wherein;

the plurality of thin film transistors control light emission of the electroluminescence element,

light emitted from the electroluminescence element is reflected from a subject to be radiated to the photodiode,

the photodiode and the plurality of thin film transistors generate an image signal from the light reflected to the photodiode,

the photodiode includes a photoelectric conversion layer that is in contact with a part of a P-type semiconductor layer and an N-type semiconductor layer,

the photoelectric conversion layer is made of an amorphous semiconductor film, and

the photoelectric conversion layer is thicker than the P-type semiconductor layer and the N-type semiconductor layer.

14. An area sensor according to claim 13, wherein the N-type semiconductor layer comprises polysilicon.

15. An area sensor according to claim 13, wherein the P-type semiconductor layer comprises polysilicon.

16. An area sensor according to claim 13, wherein the photoelectric conversion layer comprises amorphous silicon.

17. An area sensor according to claim 13, wherein the electroluminescence element has a positive electrode, a negative electrode and an electroluminescence layer provided between the positive electrode and the negative electrode.

18. An area sensor according to claim 13, wherein the area sensor is included in electronic equipment selected from the group of:

a video camera, a digital still camera, a notebook computer and a portable information terminal.

19. An area sensor comprising a sensor portion, the sensor portion comprising:

a plurality of pixels, each of the plurality of pixels comprising a photodiode, an electroluminescence element, a switching TFT, an electroluminescence driving TFT, a reset TFT, a buffer TFT and a selective TFT, wherein;

the switching TET and the electroluminescence driving TFT control light emission of the electroluminescence element,

light emitted from the electroluminescence element is reflected from a subject to be radiated to the photodiode,

the photodiode and the plurality of thin film transistors generate an image signal from the light reflected to the photodiode,

the photodiode includes a photoelectric conversion layer that is in contact with a part of a P-type semiconductor layer and an N-type semiconductor layer,

the photoelectric conversion layer is made of an amorphous semiconductor film, and

the photoelectric conversion layer is thicker than the P-type semiconductor layer and the N-type semiconductor layer.

20. An area sensor according to claim 19, wherein the N-type semiconductor layer comprises polysilicon.

21. An area sensor according to claim 19, wherein the P-type semiconductor layer comprises polysilicon.

22. An area sensor according to claim 19, wherein the photoelectric conversion layer comprises amorphous silicon.

23. An area sensor according to claim 19, wherein the electroluminescence element has a positive electrode, a negative electrode and an electroluminescence layer provided between the positive electrode and the negative electrode.

24. An area sensor according to claim 19, wherein the area sensor is included in electronic equipment selected from the group of:

a video camera, a digital still camera, a notebook computer and a portable information terminal.

25. A display apparatus comprising a sensor portion, the sensor portion comprising:

a plurality of pixels, each of the plurality of pixels comprising a photodiode, an electroluminescence element and a plurality of thin film transistors,

wherein;

the photodiode includes a photoelectric conversion layer that is in contact with a part of a P-type semiconductor layer and an N-type semiconductor layer,

the photoelectric conversion layer is made of an amorphous semiconductor film, and

the photoelectric conversion layer is thicker than the P-type semiconductor layer and the N-type semiconductor layer.

26. A display apparatus according to claim 25, wherein the N-type semiconductor layer comprises polysilicon.

27. A display apparatus according to claim 25, wherein the P-type semiconductor layer comprises polysilicon.

28. A display apparatus according to claim 25, wherein the photoelectric conversion layer comprises amorphous silicon.

29. A display apparatus according to claim 25, wherein the electroluminescence element has a positive electrode, a negative electrode and an electroluminescence layer provided between the positive electrode and the negative electrode.

30. A display apparatus according to claim 25, wherein the display apparatus is included in electronic equipment selected from the group of:

a video camera, a digital still camera, a notebook computer and a portable information terminal.

42. A display apparatus according to claim 25, wherein the display apparatus is included in electronic equipment selected from the group of:

a video camera, a digital still camera, a notebook computer and a portable information terminal.

48. A display apparatus according to claim 25, wherein the display apparatus is included in electronic equipment selected from the group of:

a video camera, a digital still camera, a notebook computer and a portable information terminal.

31. A display apparatus comprising a sensor portion, the sensor portion comprising:

a plurality of pixels, each of the plurality of pixels comprising a photodiode, an electroluminescence element and a plurality of thin film transistors,

wherein;

a light emitted from the electroluminescence element is reflected from a subject to be radiated to the photodiode,

the photodiode generates an image signal from the light reflected to the photodiode,

the photodiode includes a photoelectric conversion layer that is in contact with a part of a P-type semiconductor layer and an N-type semiconductor layer,

the photoelectric conversion layer is made of an amorphous semiconductor film, and

the photoelectric conversion layer is thicker than the P-type semiconductor layer and the N-type semiconductor layer.

32. A display apparatus according to claim 31, wherein the N-type semiconductor layer comprises polysilicon.

33. A display apparatus according to claim 31, wherein the P-type semiconductor layer comprises polysilicon.

34. A display apparatus according to claim 31, wherein the photoelectric conversion layer comprises amorphous silicon.

35. A display apparatus according to claim 31, wherein the electroluminescence element has a positive electrode, a negative electrode and an electroluminescence layer provided between the positive electrode and the negative electrode.

36. A display apparatus according to claim 31, wherein the display apparatus is included in electronic equipment selected from the group of:

a video camera, a digital still camera, a notebook computer and a portable information terminal.

37. A display apparatus comprising a sensor portion, the sensor portion comprising:

a plurality of pixels, each of the plurality of pixels comprising a photodiode, an electroluminescence element and a plurality of thin film transistors,

wherein;

the plurality of thin film transistors control light emission of the electroluminescence element,

a light emitted from the electroluminescence element is reflected from a subject to be radiated to the photodiode,

the photodiode and the plurality of thin film transistors generate an image signal from the light reflected to the photodiode,

the photodiode includes a photoelectric conversion layer that is in contact with a part of a P-type semiconductor layer and an N-type semiconductor layer,

the photoelectric conversion layer is made of an amorphous semiconductor film, and

the photoelectric conversion layer is thicker than the P-type semiconductor layer and the N-type semiconductor layer.

38. A display apparatus according to claim 37, wherein the N-type semiconductor layer comprises polysilicon.

39. A display apparatus according to claim 37, wherein the P-type semiconductor layer comprises polysilicon.

40. A display apparatus according to claim 37, wherein the photoelectric conversion layer comprises amorphous silicon.

41. A display apparatus according to claim 37, wherein the electroluminescence element has a positive electrode, a negative electrode and an electroluminescence layer provided between the positive electrode and the negative electrode.

43. A display apparatus comprising a sensor portion, the sensor portion comprising:

a plurality of pixels, each of the plurality of pixels comprising a photodiode, an electroluminescence element, a switching TFT, an electroluminescence driving TFT, a reset TFT, a buffer TFT and a selective TFT, wherein;

the switching TFT and the electroluminescence driving TFT control light emission of the electroluminescence element,

light emitted from the electroluminescence element is reflected from a subject to be radiated to the photodiode,

the photodiode and the plurality of thin film transistors generate an image signal from the light reflected to the photodiode,

the photodiode includes a photoelectric conversion layer that is in contact with a part of a P-type semiconductor layer and an N-type semiconductor layer,

the photoelectric conversion layer is made of an amorphous semiconductor film, and

the photoelectric conversion layer is thicker than the P-type semiconductor layer and the N-type semiconductor layer.

44. A display apparatus according to claim 43, wherein the N-type semiconductor layer comprises polysilicon.

45. A display apparatus according to claim 43, wherein the P-type semiconductor layer comprises polysilicon.

46. A display apparatus according to claim 43, wherein the photoelectric conversion layer comprises amorphous silicon.

47. A display apparatus according to claim 43, wherein the electroluminescence element has a positive electrode, a negative electrode and an electroluminescence layer provided between the positive electrode and the negative electrode.