Pixel arrays of image sensors, and image sensors including the pixel arrays

Patent metadata

Field	Value
Publication number	US-9640571-B2
Application number	US-201514792862-A
Country	US
Kind code	B2
Filing date	Jul 7, 2015
Priority date	Jul 11, 2014
Publication date	May 2, 2017
Grant date	May 2, 2017

Abstract

Pixel arrays of an image sensor that include a first pixel and a second pixel adjacent the first pixel are provided. The first pixel may include a first photoelectric conversion device, a first charge storage device, a first floating diffusion node and a first transfer gate. The second pixel may include a second photoelectric conversion device, a second charge storage device, a second floating diffusion node and a second transfer gate. The pixel arrays may also include a storage gate on both the first charge storage device and the second charge storage device. The storage gate may have a unitary structure.

First claim

What is claimed is:

1. A pixel array of an image sensor comprising:
a first pixel comprising:
a first photoelectric conversion device configured to generate first charges responding to light incident on the first pixel;
a first charge storage device adjacent the first photoelectric conversion device and configured to store the first charges generated by the first photoelectric conversion device;
a first floating diffusion device adjacent the first charge storage device; and
a first transfer gate configured to control transferring the first charges stored in the first charge storage device to the first floating diffusion device;

a second pixel comprising:
a second photoelectric conversion device configured to generate second charges responding to light incident on the second pixel;
a second charge storage device adjacent the second photoelectric conversion device and configured to store the second charges generated by the second photoelectric conversion device;
a second floating diffusion device adjacent the second charge storage device; and
a second transfer gate configured to control transferring the second charges stored in the second charge storage device to the second floating diffusion device; and

a storage gate on both the first charge storage device and the second charge storage device.

2. The pixel array of claim 1 , further comprising:
a storage gate control line on the storage gate and configured to transmit a storage gate control signal to the storage gate,
wherein the storage gate extends substantially parallel to the storage gate control line.

3. The pixel array of claim 2 , wherein the first pixel and the second pixel are arranged along a row direction, and
wherein the storage gate and the storage gate control line extend in the row direction.

4. The pixel array of claim 2 , wherein the first pixel and the second pixel are arranged along a column direction, and
wherein the storage gate and the storage gate control line extend in the column direction.

5. The pixel array of claim 2 , further comprising at least one contact connecting the storage gate control line to the storage gate.

6. The pixel array of claim 1 , further comprising:
a storage gate control line on the storage gate, wherein the storage gate control line is configured to transmit a storage gate control signal to the storage gate; and
a light shielding layer between the storage gate and the storage gate control line, wherein the light shielding layer is configured to block light incident on the first charge storage device and the second charge storage device.

7. The pixel array of claim 6 , further comprising at least one contact connecting the storage gate control line to the storage gate.

8. The pixel array of claim 1 , further comprising:
a light shielding and storage gate control line on the storage gate, wherein the light shielding and storage gate control line is configured to transmit a storage gate control signal to the storage gate and is configured to block light incident on the first charge storage device and the second charge storage device.

9. The pixel array of claim 8 , wherein the light shielding and storage gate control line is on the storage gate.

10. The pixel array of claim 8 , wherein the light shielding and storage gate control line is a lowest one of a plurality of wiring layers on a substrate on which the pixel array is.

11. The pixel array of claim 1 , wherein the storage gate is on a first surface of a substrate on which the pixel array is, and the pixel array further comprises:
a storage gate control line on the storage gate and configured to transmit a storage gate control signal to the storage gate; and
a light shielding layer on a second surface of the substrate opposite the first surface of the substrate and configured to block light incident on the first charge storage device and the second charge storage device.

12. The pixel array of claim 1 , further comprising:
a first reset gate transistor configured to receive a reset signal to reset the first floating diffusion device responsive to the reset signal;
a first source follower configured to generate a first electrical signal corresponding to charges of the first floating diffusion device;
a first select transistor configured to transmit the first electrical signal to a first output line responsive to a selection signal;
a second reset gate transistor configured to receive a reset signal to reset the second floating diffusion device responsive to the reset signal;
a second source follower configured to generate a second electrical signal corresponding to charges of the second floating diffusion device; and
a second select transistor configured to transfer the second electrical signal to a second output line responsive to the selection signal.

13. The pixel array of claim 12 , wherein the first pixel and the second pixel are arranged in a row direction,
wherein the pixel array further includes a third pixel spaced apart from the first pixel in a column direction, and
wherein the first reset gate transistor, the first source follower and the first select transistor are configured to be shared by the first pixel and the third pixel.

14. A pixel array of an image sensor comprising:
a plurality of pixels arranged in a matrix having a plurality of rows and a plurality of columns,
wherein ones of the plurality of pixels include a photoelectric conversion device, a charge storage device, a transfer gate and a floating diffusion device, and
wherein at least two pixels of the plurality of pixels corresponding to given one of the plurality of rows include a storage gate that comprises a unitary structure.

15. The pixel array of claim 14 , wherein the at least two pixels of the plurality of pixels comprise a first pixel comprising a first photoelectric conversion device and a first charge storage device and a second pixel comprising a second photoelectric conversion device and a second charge storage device, and
wherein the storage gate overlaps both a space between the first photoelectric conversion device and the first charge storage device and a space between the second photoelectric conversion device and the second charge storage device in plan view.

16. An image sensor comprising:
a first pixel comprising a first photoelectric conversion device and a first charge storage device that are on a substrate, the first charge storage device being configured to store first charges generated in the first Photoelectric conversion device;
a second pixel comprising a second photoelectric conversion device and a second charge storage device that are on the substrate, the second charge storage device being configured to store second charges generated in the second photoelectric conversion device; and
a unitary storage gate configured to control transferring the first charges from the first photoelectric conversion device to the first charge storage device and the second charges from the second photoelectric conversion device to the second charge storage device.

17. The image sensor of claim 16 , further comprising a storage gate control line that is configured to transmit a storage gate control signal to the unitary storage gate and extends substantially parallel to the unitary storage gate.

18. The image sensor of claim 17 , further comprising a light shielding layer between the storage gate control line and the unitary storage gate, wherein the light shielding layer is on both the first charge storage device and the second charge storage device.

Assignees

• Kim Seung-Sik
• Kim Young-Chan
• Shim Eun-Sub
• Oh Min-Seok
• Lee Ji-Won
• Lim Moo-Sup
• Kim Tae-Han
• Yang Dong-Joo
• Samsung Electronics Co Ltd

Inventors

• Kim Seung-Sik
• Kim Young-Chan
• Shim Eun-Sub
• Oh Min-Seok
• Lee Ji-Won
• Lim Moo-Sup
• Kim Tae-Han
• Yang Dong-Joo

Classifications

• H01L27/14641

  Electricity · mapped topic

• H01L27/14603

  Electricity · mapped topic

• H01L27/14612 Primary

  Electricity · mapped topic

• H01L27/14623

  Electricity · mapped topic

• H10F39/8057

  Optical shielding · CPC title