Pixel cells in a honeycomb arrangement

• US 7,511,323 B2
• Filed: 08/11/2005
• Issued: 03/31/2009
• Est. Priority Date: 08/11/2005
• Status: Active Grant

• Current Assignee: Aptina Imaging Corporation (ON Semiconductor Corporation)
• Original Assignee: Aptina Imaging Corporation (ON Semiconductor Corporation)
• Inventors: McKee, Jeffrey A.
• Primary Examiner(s): Smith; Zandra
• Assistant Examiner(s): Patton; Paul E
• Application Number:
  US11/201,327
• Publication Number:
  US 20070034884A1
• Time in Patent Office: 1,328 Days
• Field of Search: 257290-294, 348311-315, 438/73, 438/75, 438/78
• US Class Current: 257/294
• 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 27/14621 Colour filter arrangements
• 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: H04N 25/76 Addressed sensors, e.g. MOS or CMOS sensors
• 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

Abstract

The present invention, in the various exemplary embodiments, provides a RGB color filter array. The red, green and blue pixel cells are arranged in a honeycomb pattern. The honeycomb layout provides the space to vary the size of pixel cells of an individual color so that, for example, the photosensor of blue pixels can be made larger than that of the red or green pixels. In another aspect of the invention, depicted in the exemplary embodiments, the honeycomb structure can also be implemented with each pixel row having a same color of pixel cells which can simplify can conversion in the readout circuits. In another aspect of the invention, the RGB honeycomb pixel array may be implemented using a shared pixel cell architecture.

Claims

1. An imager comprising:

an array of pixel cells, said array of pixel cells being configured in a honeycomb pattern in rows and columns, and each of said pixel cells comprising a photosensor configured to collect charge; and

a color filter formed over the photosensor,

wherein a plurality of said pixel cells share pixel components, said shared pixel components comprise a diffusion region, a reset transistor, a row select transistor, and a source follower transistor, and each row of said pixel cells within said honeycomb pattern comprises one color of pixel cells, where said shared pixel components are shared by at least two pixel cells from a first column of said array and one pixel cell from a second column of said array.

2. The imager of claim 1, wherein a number of said plurality of the pixel cells sharing pixel components is a multiple of three.

3. The imager of claim 2, wherein the pixel cells sharing pixel have an equal proportion of blue color pixels, green color pixels and red color pixels.

4. The imager of claim 2, wherein the number of said plurality of pixel cells sharing pixel components is three pixel cells.

5. The imager of claim 2, wherein the number of said plurality of pixel cells sharing pixel components is six pixel cells,

6. The imager of claim 1, wherein each pixel cell further comprises a transfer transistor for transferring charge from the photosensor to a shared diffusion region.

7. The imager of claim 1, wherein a pixel size of a predetermined plurality of pixel cells of a first color have a photosensor of a different size then a remaining plurality of pixel color cells.

8. The imager of claim 1, wherein a pixel size of a plurality of green color pixel cells is larger than a plurality of the remaining plurality of pixel color cells.

9. The imager of claim 1, wherein a pixel size of a plurality of blue color pixel cells is larger than a plurality of the remaining plurality of pixel color cells.

10. The imager of claim 1, wherein each photosensor in a row of said array of pixels has said color filter formed of the same color.

11. An imager system, comprising:

a processor;

an imaging device coupled to said processor, said imaging device comprising a plurality of photosensors in rows and columns for collecting charge; and

a color filter formed over each of said plurality of photosensors, said plurality of photosensors being formed in a honeycomb pattern,

wherein a plurality of photosensors share pixel components, said shared pixel components comprise a reset transistor, a source follower transistor and row select transistor, and each row of said honeycomb pattern comprises color filters of the same color, where said shared pixel components share at least two pixel cells from a first column of said array and one pixel cell from a second adjacent column of said array.

12. The system according to claim 11, wherein said plurality of photosensors sharing pixel components is three pixels.

13. The system according to claim 11, wherein said plurality of photosensors sharing pixel components is six pixels.

14. The system according to claim 11, wherein said shared pixel components further comprises a diffusion region.

15. The system according to claim 11, wherein said imaging device further comprises a plurality of microlens formed over said plurality of photosensors.

16. The system according to claim 11, wherein said imaging device further comprises at least one transfer transistor for transferring charge from said photosensors to a diffusion region.

17. An imaging device comprising:

a pixel array comprising an array of rows and columns of pixels sharing at least a diffusion region, a reset transistor, a row select transistor, and a source follower transistor;

a color filter array formed over said pixels;

wherein the array of pixels and the color filter array are formed over the pixel array and are formed in a honeycomb pattern having a row of said pixels corresponding to each colors,

where said shared diffusion region. reset transistor, row select transistor, and source follower transistor are shared having at least two pixel cells from a first column of said array and one pixel cell from an adjacent second column of said array.

18. The imaging device of claim 17, wherein a number of said plurality of the pixel cells sharing pixel components is a multiple of three.

19. An imager comprising:

an array of pixel cells in rows and columns, each of said pixel cells comprising a photosensor configured to collect charge, said array of pixel cells being arranged in a honeycomb pattern, and configured to share a diffusion region, a reset transistor, a row select transistor, and a source follower transistor, wherein each row of said array of pixel cells corresponds to one color,

where said shared pixel components are shared by at least two pixel cells from a first column of said array and one pixel cell from a second column of said array.

20. The imager of claim 19, wherein a number of said plurality of the pixel cells sharing pixel components is a multiple of three.

21. The imager of claim 19, wherein each pixel cell further comprises a transfer transistor for transferring charge from the photosensor to a shared diffusion region.

22. The imager of claim 19, wherein the pixel size of a predetermined plurality of pixel cells have a photosensor of a different size then the remaining plurality of pixel cells.

23. The imager of claim 19, wherein said plurality of pixel cells sharing pixel components is 3 pixel cells.

24. The imager of claim 19, wherein said plurality of pixel cells sharing pixel components is 6 pixel cells.

25. A CMOS imager comprising:

an array of pixel cells, each of said pixel cells comprising a photosensor configured to collect charge; and

a color filter array in rows and columns formed over said pixels, wherein the array of pixels and the color filter array formed over the pixel array are formed in a honeycomb pattern and wherein one color of pixel cells is larger than a remaining plurality of pixel cells, where said honeycomb patter of pixels include at least two pixel cells from a first column of said array and one pixel cell from an adjacent second column of said array.

26. The imager of claim 25, wherein a plurality of said pixel cells share pixel components.

27. The imager of claim 26, wherein said plurality of pixel cells sharing pixel components is 3 pixel cells.

28. The imager of claim 26, wherein said plurality of pixel cells sharing pixel components is 6 pixel cells.

29. The imager of claim 26, wherein said shared pixel components comprise a diffusion region, a reset transistor, a row select transistor, and a source follower transistor.

30. The imager of claim 26, wherein a number of said plurality of the pixel cells sharing pixel components is a multiple of three.

31. The imager of claim 25, wherein each pixel cell further comprises a transfer transistor for transferring charge from the photosensor to a shared diffusion region.

32. A CMOS imager comprising:

an array of pixel cells, each of said pixel cells comprising a photosensor configured to collect charge, said array of pixel cells being arranged in a honeycomb pattern, wherein one color of pixel cells is larger than a remaining plurality of pixel cells, where said honeycomb pattern of pixels includes at least two pixel cells from a first column of said array and one pixel cell from a second column of said array.

33. The imager of claim 32, wherein a plurality of said pixel cells share pixel components.

34. The imager of claim 33, wherein said plurality of pixel cells sharing pixel components is 3 pixel cells.

35. The imager of claim 33, wherein said plurality of pixel cells sharing pixel components is 6 pixel cells.

36. The imager of claim 33, wherein said shared pixel components comprise a diffusion region, a reset transistor, a row select transistor, and a source follower transistor.

37. The imager of claim 33, wherein a number of said plurality of the pixel cells sharing pixel components is a multiple of three.

38. The imager of claim 32, wherein each pixel cell further comprises a transfer transistor for transferring charge from the photosensor to a shared diffusion region.

39. A CMOS imager comprising:

n array of pixel cells, each of said pixel cells comprising a photosensor configured to collect charge, said array of pixel cells in rows and columns being arranged in a honeycomb pattern; and

shared readout circuitry formed arranged between pixel cells in said honeycomb pattern where said shared readout circuitry are shared having at least two pixel cells from a first column of said array and one pixel cell from an adjacent second column of said array.