Active pixel sensor with a diagonal active area

• US 7,692,705 B2
• Filed: 09/15/2003
• Issued: 04/06/2010
• Est. Priority Date: 06/17/1999
• Status: Expired due to Fees

• Current Assignee: Round Rock Research LLC
• Original Assignee: Micron Technology, Inc.
• Inventors: Rhodes, Howard E.
• Primary Examiner(s): Tran; Sinh
• Assistant Examiner(s): BERARDESCA, PAUL M
• Application Number:
  US10/661,494
• Publication Number:
  US 20040080648A1
• Time in Patent Office: 2,395 Days
• Field of Search: 345/75.2, 250/208.1, 348/308
• US Class Current: 348/308
• 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 25/779 Circuitry for scanning or addressing the pixel array
• CPC Class Codes: H04N 25/7795 Circuitry for generating timing or clock signals
• CPC Class Codes: H04N 3/1512 for MOS image-sensors, e.g. MOS-CCD H04N3/1581 takes precedence

Abstract

An imaging device formed as a CMOS semiconductor integrated circuit having two adjacent pixels in a row connected to a common column line. By having adjacent pixels of a row share column lines, the CMOS imager circuit eliminates half the column lines of a traditional imager allowing the fabrication of a smaller imager. The imaging device also may be fabricated to have a diagonal active area to facilitate contact of two adjacent pixels with the single column line and allow linear row select lines, reset lines and column lines.

Claims

1. An imager structure, comprising:

a pixel array having pixels arranged in rows and columns;

said pixel array comprising a first pixel and a second pixel formed in respectively adjacent columns and in conjunction with an active area spanning a first associated photodetector of the first pixel and a second associated photodetector of the second pixel but no other photodetectors of other pixels, said active area having the first associated photodetector and the second associated photodetector at opposite ends of said active area and having a two-dimensional shape as the pixel array is viewed from above; and

a common output for charges generated from the first photodetector and the second photodetector at a portion of said active area between said first and second photodetectors, the common output being coupled to a signal output line shared by the first pixel and the second pixel, wherein the two-dimensional shape of said active area between the first and second associated photodetectors comprises an active area component that extends diagonally with respect to an extending direction of said signal output line within the pixel array.

2. The pixel array of claim 1, wherein the active area is S-shaped.

6. The pixel array of claim 1, wherein the active area covers the first and second associated photodetectors and a continuous area spanning the first and second associated photodetectors.

7. The pixel array of claim 1, wherein the first pixel and the second pixel are in the same row of the pixel array, but are spatially offset from one another in both an X and a Y dimension as viewed from above the pixel array, wherein the X dimension corresponds to an extending direction of the row across the pixel array and the Y dimension corresponds to an orthogonal direction across the pixel array relative to the X dimension.

3. A pixel array, comprising:

a first pixel and a second pixel, the first pixel having a first photodetector and the second pixel having a second photodetector, wherein an active area is shared by only the first photodetector and the second photodetector, said shared active area providing an output for said first and second photodetectors and having a two-dimensional shape as the pixel array is viewed from above; and

a common readout line for receiving a signal from said first and second photodetectors coupled to the active area shared by the first pixel and the second pixel, wherein the two-dimensional shape of the shared active area between the first and second photodetectors comprises an active area component that extends diagonally relative to an extending direction of the common readout line across the pixel array.

4. The pixel array of claim 3, wherein the active area shared by the first and second pixels is S-shaped.

8. The pixel array of claim 3, wherein the active area covers the first and second photodetectors and a continuous area spanning the first and second photodetectors.

9. The pixel array of claim 3, wherein the first pixel and the second pixel are in the same row of the pixel array, but are spatially offset from one another in both an X and a Y dimension as viewed from above the pixel array, wherein the X dimension corresponds to an extending direction of the row across the pixel array and the Y dimension corresponds to an orthogonal direction across the pixel array relative to the X dimension.

5. A pixel array, comprising:

a first pixel and a second pixel, said first pixel having a first photodetector and said second pixel having a second photodetector, wherein an active area is shared by only said first photodetector and said second photodetector, and at least one of said first pixel and said second pixel further comprises a reset transistor, said reset transistor comprising a gate, a first source-drain region, and a second source-drain region in a linear arrangement as viewed from above the pixel array, wherein said shared active area between the first and second photodetectors has a two-dimensional shape as the pixel array is viewed from above, the two-dimensional shape comprising an active area component that extends diagonally relative to the linear arrangement of the reset transistor as the pixel array is viewed from above; and

a common readout line for receiving charge from said shared active area.

10. The pixel array of claim 5, wherein the active area covers the first and second photodetectors and a continuous area spanning the first and second photodetectors.

11. The pixel array of claim 5, wherein the first pixel and the second pixel are in the same row of the pixel array, but are spatially offset from one another in both an X and a Y dimension as viewed from above the pixel array, wherein the X dimension corresponds to an extending direction of the row across the pixel array and the Y dimension corresponds to an orthogonal direction across the pixel array relative to the X dimension.