Active pixel image sensor with shared amplifier read-out

• US 6,107,655 A
• Filed: 08/15/1997
• Issued: 08/22/2000
• Est. Priority Date: 08/15/1997
• Status: Expired due to Term

• Current Assignee: Omnivision Technologies Incorporated (Will Semiconductor Co., Ltd. Shanghai)
• Original Assignee: Eastman Kodak Company
• Inventors: Guidash, Robert M.
• Primary Examiner(s): Ngo , Ngan V.
• Application Number:
  US08/911,235
• Time in Patent Office: 1,103 Days
• Field of Search: 257/231, 257/232, 257/233, 257/239
• US Class Current: 257/233
• CPC Class Codes: H01L 27/14603 Special geometry or disposition of pixel-elements, address-lines or gate-electrodes
• 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 27/14641 Electronic components shared by two or more pixel-elements, e.g. one amplifier shared by two pixel elements
• CPC Class Codes: H01L 27/14643 Photodiode arrays; MOS imagers
• CPC Class Codes: H04N 25/75 Circuitry for providing, modifying or processing image signals from the pixel array
• CPC Class Codes: H04N 25/778 comprising amplifiers shared between a plurality of pixels, i.e. at least one part of the amplifier must be on the sensor array itself
• CPC Class Codes: H04N 25/78 Readout circuits for addressed sensors, e.g. output amplifiers or A/D converters

Abstract

An image sensor having a plurality of pixels arranged in a series of row and columns comprising: a semiconductor substrate having a plurality of pixels formed in rows and columns with at least two row adjacent pixels and at least two column adjacent pixels formed within the substrate; and at least one electrical function integrated within the adjacent pixels that is shared between the adjacent pixels. The electrical function can be either a contact region or an electrical circuit used in implementing either a photogate, a transfer gate, a reset gate, a row select gate, an amplifier drain, an output node, a floating diffusion contact, a reset drain, a lateral overflow gate, an overflow drain or an amplifier.

Claims

1. An image sensor having a plurality of pixels arranged in a series of rows and columns comprising:

a semiconductor material of a first conductivity type;

at least two row adjacent pixels and at least two column adjacent pixels formed within the substrate; and

at least one shared contact region wherein the contact region is shared between the adjacent pixels and wherein the shared contact is selected from one of the following components (a photogate contact, a reset gate contact, a row select gate contact, an amplifier drain contact, an output node contact, a floating diffusion contact, a reset drain contact, a lateral overflow gate contact, or an amplifier contact).

2. The image sensor of claim 1 wherein the shared function further comprises a shared electrical component.

3. The image sensor of claim 1 wherein the shared function further comprises a shared contact region but not a shared electrical component between the adjacent pixels.

4. The image sensor of claim 1 wherein the shared function further comprises both a shared contact region and a shared electrical component.

5. The image sensor of claim 4 wherein the electrical component is selected from one of the following components (a reset transistor, a row select transistor, an amplifier drain, an output node, a floating diffusion, a lateral overflow gate, or an amplifier).

6. The image sensor of claim 1 further comprising a voltage supply of one pixel that is also used as an overflow drain for the adjacent pixel.

7. An image sensor having a plurality of pixels arranged in rows and columns comprising:

a row select signal that is operative to concurrently select two row adjacent pixels and a row select bus that is operative for the two row adjacent pixels;

a column output bus operative for two column adjacent pixels;

a separate transfer gate for each of the pixels; and

a separate transfer gate bus for every other pixel within a given row.

8. The image sensor of claim 7 further comprising a 1:

2 column bus de-multiplexing scheme for each pair of columns.

9. The image sensor of claim 7 further comprising a contact region formed on an electrical component that is shared by the adjacent pixels.

10. The image sensor of claim 7 further comprising a contact region formed on each of the adjacent pixels for operation of an electrical component that is shared.

11. An image sensor having a plurality of pixels arranged in rows and columns arranged on a semiconductor substrate comprising:

at least two row adjacent pixels and at least two column adjacent pixels each having a photodetector formed within the substrate;

transfer gate provided for each pixel, the transfer gate being connected to a sense node.

12. The image sensor of claim 11 further comprising a shared contact region that is shared by at least two of the adjacent pixels.

13. The image sensor of claim 11 further comprising a shared electrical component that is shared between at least two of the adjacent pixels and wherein the shared component is selected from one of the following components (a reset gate, a row select gate, an amplifier drain, an output node, a floating diffusion, a reset drain, a lateral overflow gate, an overflow drain or an amplifier).

14. The image sensor of claim 13 wherein the electrical component is constructed with at least a portion of the electrical component formed along a common border of the adjacent pixels that share the electrical component.

15. The image sensor of claim 11 further comprising a voltage source of one of the adjacent pixels is also used as an overflow drain for another of the adjacent pixels.

17. The image sensor of claim 15 further comprising a column output bus operative for two column adjacent pixels.

18. The image sensor of claim 17 further comprising a 1:

2 column bus de-multiplexing scheme for each pair of columns.

19. The image sensor of claim 15 further comprising a shared contact region.

16. An image sensor having a plurality of pixels arranged in a series of rows and columns comprising:

a semiconductor material of a first conductivity type;

at least two row adjacent pixels and at least two column adjacent pixels formed within the substrate; and

at least one electrical component that is shared between the adjacent pixels wherein the electrical component is selected from one of the following components (a reset transistor, a row select transistor, an amplifier drain, an output node, a floating diffusion, a lateral overflow gate, or an amplifier).