Semiconductor device
View Patent ↗A semiconductor device is provided in which each pixel includes an electric circuit (a bootstrap circuit) for generating an electric potential that is higher than a voltage given through capacitative coupling. Also, there is provided a semiconductor device in which a sufficient signal amplitude can be attained by using the electric circuit to set a potential difference between both terminals of a photoelectric conversion element to the same value as the power source potential. Further, there is provided a semiconductor device in which the number of manufacturing steps is reduced by using transistors having a single polarity to constitute each pixel, thereby achieving increased yield and reduced costs.
1. A semiconductor device having a plurality of pixels, each of the pixels comprising:
a switching transistor;
an amplification transistor electrically connected to the switching transistor;
a reset transistor electrically connected to a gate electrode of the amplification transistor;
a boot transistor electrically connected to a gate electrode of the reset transistor;
a discharge transistor electrically connected to the gate electrode of the amplification transistor; and
a photoelectric conversion element electrically connected to the gate electrode of the amplification transistor;
wherein transistors included in the each of the pixels have the same conductivity type.
2. A device according to claim 1 , wherein the transistors included in the each of the pixels are n-channel type.
3. A device according to claim 1 , wherein the transistors included in the each of the pixels are n-channel type.
4. A device according to claim 1 , wherein the semiconductor device is an electric device having a hand scanner.
5. A device according to claim 1 , wherein the semiconductor device is an electric device selected from the group consisting of a video camera, a digital camera, a lap-top computer, a portable information terminal, a mobile computer, a cellular phone, a portable game machine, and an electronic book.
6. A semiconductor device having a plurality of pixels, each of the pixels comprising:
a plurality of transistors;
a photoelectric conversion element having two electrodes;
power source supply means;
a bootstrap circuit for setting a potential difference between the both electrodes of the photoelectric conversion element to the same potential as the power source supply means; and
a light emitting element,
wherein light emitted from the light emitting element is irradiated onto a subject and light reflected by the subject is irradiated onto the photoelectric conversion element, and
wherein transistors included in each of the pixels have the same conductivity type.
7. A device according to claim 6 , wherein the transistors included in the each of the pixels are n-channel type.
8. A device according to claim 6 , wherein the transistors included in the each of the pixels are p-channel type.
9. A device according to claim 6 , wherein the plurality of transistors comprise at least a switching transistor, an amplification transistor, and a reset transistor.
10. A device according to claim 6 , wherein the semiconductor device is an electric device having a band scanner.
11. A device according to claim 6 , wherein the semiconductor device is an electric device selected from the group consisting of a video camera, a digital camera, a lap-top computer, a portable information terminal, a mobile computer, a cellular phone, a portable game machine, and an electronic book.
12. A semiconductor device having a plurality of pixels, each of the pixels comprising:
a switching transistor;
an amplification transistor electrically connected to the switching transistor;
a reset transistor electrically connected to a gate electrode of the amplification transistor;
a boot transistor electrically connected to a gate electrode of the reset transistor;
a capacitor electrically connected to the gate electrode of the amplification transistor and the gate electrode of the reset transistor;
a discharge transistor electrically connected to the gate electrode of the amplification transistor; and
a photoelectric conversion element electrically connected to the gate electrode of the amplification transistor;
wherein the transistors included in each of the pixels have the same conductivity type.
13. A device according to claim 12 , wherein the transistors included in the each of the pixels are n-channel type.
14. A device according to claim 12 , wherein the transistors included in the each of the pixels are n-channel type.
15. A device according to claim 12 , wherein the gate electrode of the reset transistor is set to a potential higher than that of a power source supply means due to capacitive coupling by the capacitor.
16. A device according to claim 12 , wherein the semiconductor device is an electric device having a hand scanner.
17. A device according to claim 12 , wherein the semiconductor device is an electric device selected from the group consisting of a video camera, a digital camera, a lap-top computer, a portable information terminal, a mobile computer, a cellular phone, a portable game machine, and an electronic book.
18. A semiconductor device having a plurality of pixels, each of the pixels comprising:
a plurality of transistors;
a photoelectric conversion element having two electrodes;
power source supply means;
a bootstrap circuit; and
a light emitting element,
wherein the bootstrap circuit comprises:
a discharge transistor for setting the both electrodes of the photoelectric conversion element to the same potential;
a boot transistor which has a gate electrode, a first electrode, and a second electrode and which is turned off wherein a signal is inputted to the lust electrode, the gate electrode being connected to the power source supply means; and
a capacitor arranged between the photoelectric conversion element and the second electrode of the boot transistor,
wherein light emitted from the light emitting element is irradiated onto a subject and light reflected by the subject is irradiated onto the photoelectric conversion element, and
wherein the transistors included in each of the pixels have the same conductivity type.
19. A device according to claim 18 , wherein the transistors included in the each of the pixels are n-channel type.
20. A device according to claim 18 , wherein the transistors included in the each of the pixels are p-channel type.
21. A device according to claim 18 , wherein the plurality of transistors comprise at least a switching transistor, an amplification transistor and a reset transistor.
22. A device according to claim 21 , wherein the reset transistor has a gate electrode that is set to a potential higher than that of the power source supply means due to capacitive coupling by the capacitor.
23. A device according to claim 18 , wherein the semiconductor device is an electric device having a hand scanner.
24. A device according to claim 18 , wherein the semiconductor device is an electric device selected from the group consisting of a video camera, a digital camera, a lap-top computer, a portable information terminal, a mobile computer, a cellular phone, a portable game machine, and an electronic hook.
25. A semiconductor device having a plurality of pixels, each of the pixels comprising:
a plurality of transistors comprising at least a switching transistor, an amplification transistor, and a reset transistor;
a photoelectric conversion element having first and second terminals;
power source supply means;
a bootstrap circuit;
a discharge signal line: and
a reset signal line,
wherein the bootstrap circuit comprises:
a discharge transistor and a boot transistor, each having a gate electrode, a source region, and a drain region; and
a capacitor having first and second terminals;
wherein the gate electrode of the discharge transistor is connected to the discharge signal line,
wherein one of the source region and the drain region of the discharge transistor is connected to the first terminal of the photoelectric conversion element, and the other is grounded,
wherein the gate electrode of the boot transistor is connected to the power source supply means,
wherein one of the source region and the drain region of the boot transistor is connected to the reset signal line, and the other is connected to the gate electrode of the reset transistor and to the first terminal of the capacitor,
wherein a gate electrode of the reset transistor is connected to the first terminal of the capacitor,
wherein one of a source region and a drain region of the reset transistor is connected to the power source supply means, and the other is connected to the second terminal of the capacitor and to the first terminal of the photoelectric conversion element, and
wherein the transistors included in each of the pixels have the same conductivity type.
26. A device according to claim 25 , wherein the transistors included in the each of the pixels arc n-channel type.
27. A device according to claim 25 , wherein the transistors included in the each of the pixels are p-channel type.
28. A device according to claim 25 , wherein the semiconductor device is an electric device having a hand scanner.
29. A device according to claim 25 , wherein the semiconductor device is an electric device selected from the group consisting of a video camera, a digital camera, a lap-top computer, a portable information terminal, a mobile computer, a cellular phone, a portable game machine, and an electronic book.
30. A semiconductor device having a plurality of pixels, each of the pixels comprising;
a plurality of transistors;
a photoelectric conversion element having first and second terminals;
power source supply means;
a bootstrap circuit;
a light emitting element;
a discharge signal line; and
a reset signal line,
wherein the bootstrap circuit comprises:
a discharge transistor, and a boot transistor, each having a gate electrode, a source region, and a drain region; and
a capacitor having first and second terminals;
wherein the gate electrode of the discharge transistor is connected to the discharge signal line;
wherein one of the source region and the drain region of the discharge transistor is connected to the first terminal of the photoelectric conversion element, and the other is grounded;
wherein the gate electrode of the boot transistor is connected to the power source supply means;
wherein one of the source region and the drain region of the boot transistor is connected to the reset signal line, and the other is connected to the gate electrode of the reset transistor and to the first terminal of the capacitor;
wherein the gate electrode of the reset transistor is connected to the first terminal of the capacitor;
wherein one of the source region and the drain region of the reset transistor is connected to the power source supply means, and the other is connected to the second terminal of the capacitor and to the first terminal of the photoelectric conversion element;
wherein light emitted from the light emitting element is irradiated onto a subject and light reflected by the subject is irradiated onto the photoelectric conversion element; and
wherein the transistors included in each of the pixels have the same conductivity type.
31. A device according to claim 30 , wherein the transistors included in the each of the pixels are n-channel type.
32. A device according to claim 30 , wherein the transistors included in the each of the pixels are n-channel type.
33. A device according to claim 30 , wherein the semiconductor device is an electric device having a hand scanner.
34. A device according to claim 30 , wherein the semiconductor device is an electric, device selected from the group consisting of a video camera, a digital camera, a lap-top computer, a portable information terminal, a mobile computer, a cellular phone, a portable game machine, and an electronic book.
35. A semiconductor device having a pixel region, the pixel region comprising a plurality of pixels and each of the pixels comprising:
a switching element comprising a switching transistor;
an amplification element comprising an amplification transistor;
a reset element comprising a reset transistor;
a bootstrap circuit comprising;
a discharge transistor electrically connected to a gate electrode of the amplification transistor;
a boot transistor electrically connected to a gate electrode of the reset transistor; and
a capacitor electrically connected to the gate electrode of the amplification transistor and the sate electrode of the reset transistor; and
a photoelectric conversion circuit,
wherein the switching transistor, the amplification transistor, the reset transistor, the discharge transistor, and the boot transistor have the same conductivity.
36. A device according to claim 35 , wherein the transistors included in the each of the pixels are n-channel type.
37. A device according to claim 35 , wherein the transistors included in the each of the pixels are p-channel type.
38. A device according to claim 35 , wherein the each of the pixels further comprises; a source signal line; a gate signal line; power source lines; a power source reference line; a discharge signal line; and a reset signal line, a power source reference line.
39. A device according to claim 35 , wherein the each of the pixels further comprises a light emitting element portion.
40. A device according to claim 35 , wherein the semiconductor device is an electric device having a hand scanner.
41. A device according to claim 35 , wherein the semiconductor device is an electric device selected from the group consisting of a video camera, a digital camera, a lap-top computer, a portable information terminal, a mobile computer, a cellular phone, a portable game machine, and an electronic book.