Pinned-photodiode pixel with global shutter
View Patent ↗An image sensor includes a two-dimensional array of pixels having a photodetector for collecting charge in response to incident light; a storage region adjacent the photodetector that receives the charge from the photodetector; a sense node adjacent the storage region that receives the charge from the storage region and converts the charge to a voltage signal; and an input to an amplifier for sensing the voltage signal from the sense node.
1. An image sensor comprising:
a two-dimensional array of pixels comprising:
(a) a photodetector for collecting charge in response to incident light;
(b) a storage region adjacent the photodetector that receives the charge from the photodetector; wherein the storage region is optimized for low dark current and low charge generation defects;
(c) a sense node adjacent the storage region that receives the charge from the storage region and converts the charge to a voltage signal;
(d) a doped region surrounding only the storage region and the sense node for substantially shielding the storage region and the sense node from photo-generated charge not transferred from the photodetector; and
(e) an input to an amplifier for sensing the voltage signal from the sense node.
2. The image sensor as in claim 1 , wherein each pixel comprises the photodetector and the storage region.
3. The image sensor as in claim 2 , wherein the sense node and the input to the amplifier are shared by a subset of pixels.
4. The image sensor as in claim 1 wherein each pixel comprises the photodetector, storage region, sense node and the input to the amplifier.
5. The image sensor as in claim 1 , wherein the storage region is a pinned photodiode.
6. The image sensor as in claim 1 , wherein the photodetector is a pinned photodiode.
7. The image sensor as in claim 1 further comprising a lightshield spanning a substantial portion or all of the sense node.
8. The image sensor as in claim 7 , wherein the lightshield is substantially 50 to 500 nanometers from a top surface of a semiconductor in the sense node.
9. The image sensor as in claim 7 , wherein the lightshield spans both the sense node and a substantial portion or all of the storage region.
10. The image sensor as in claim 1 further comprising an overflow drain adjacent the photodetector.
11. A camera comprising:
an image sensor comprising:
a two-dimensional array of pixels comprising:
(a) a photodetector for collecting charge in response to incident light;
(b) a storage region adjacent the photodetector that receives the charge from the photodetector; wherein the storage region is optimized for low dark current and low charge generation defects;
(c) a sense node adjacent the storage region that receives the charge from the storage region and converts the charge to a voltage signal;
(d) a doped region surrounding only the storage region and the sense node for substantially shielding the storage region and the sense node from photo-generated charge not transferred from the photodetector; and
(e) an input to an amplifier for sensing the voltage signal from the sense node.
12. The camera as in claim 11 , wherein each pixel comprises the photodetector and the storage region.
13. The camera as in claim 12 , wherein the sense node and the input to the amplifier are shared by a subset of pixels.
14. The camera as in claim 11 wherein each pixel comprises the photodetector, storage region, sense node and the input to the amplifier.
15. The camera as in claim 11 , wherein the storage region is a pinned photodiode.
16. The camera as in claim 11 , wherein the photodetector is a pinned photodiode.
17. The camera as in claim 11 further comprising a lightshield spanning a substantial portion or all of the sense node.
18. The camera as in claim 17 , wherein the lightshield is substantially 50 to 500 nanometers from a top surface of a semiconductor in the sense node.
19. The camera as in claim 17 , wherein the lightshield spans both the sense node and a substantial portion or all of the storage region.
20. The camera as in claim 11 further comprising an overflow drain adjacent the photodetector.