Solid-state imaging element, method for driving the same, and camera system

• US 20050036050A1
• Filed: 09/20/2004
• Published: 02/17/2005
• Est. Priority Date: 06/08/1998
• Status: Active Grant

• Current Assignee: Kazuya Yonemoto, Koichi Shiono, Ryoji Suzuki, Takahisa Ueno
• Original Assignee: Kazuya Yonemoto, Koichi Shiono, Ryoji Suzuki, Takahisa Ueno
• Inventors: Yonemoto, Kazuya, Suzuki, Ryoji, Ueno, Takahisa, Shiono, Koichi
• Granted Patent: US 7,944,491 B2
• Time in Patent Office: Days
• US Class Current: 348/308
• 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 27/14612 involving a transistor
• CPC Class Codes: H01L 27/14638 Structures specially adapted for transferring the charges across the imager perpendicular to the imaging plane
• CPC Class Codes: H01L 27/14643 Photodiode arrays; MOS imagers
• CPC Class Codes: H04N 25/00 Circuitry of solid-state image sensors [SSIS]; Control thereof
• CPC Class Codes: H04N 25/40 Extracting pixel data from image sensors by controlling scanning circuits, e.g. by modifying the number of pixels sampled or to be sampled
• CPC Class Codes: H04N 25/441 by reading contiguous pixels from selected rows or columns of the array, e.g. interlaced scanning
• CPC Class Codes: H04N 25/65 applied to reset noise, e.g. KTC noise related to CMOS structures by techniques other than CDS
• CPC Class Codes: H04N 25/767 Horizontal readout lines, multiplexers or registers
• CPC Class Codes: H04N 25/77 Pixel circuitry, e.g. memories, A/D converters, pixel amplifiers, shared circuits or shared components
• 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 3/1512 for MOS image-sensors, e.g. MOS-CCD H04N3/1581 takes precedence
• CPC Class Codes: H04N 3/155 Control of the image-sensor operation, e.g. image processing within the image-sensor

Abstract

Since the great number of elements constituting a unit pixel having an amplification function would hinder reduction of pixel size, unit pixel n,m arranged in a matrix form is comprised of a photodiode, a transfer switch for transferring charges stored in the photodiode, a floating diffusion for storing charges transferred by the transfer switch, a reset switch for resetting the floating diffusion, and an amplifying transistor for outputting a signal in accordance with the potential of the floating diffusion to a vertical signal line, and by affording vertical selection pulse φ Vn to the drain of the reset switch to control a reset potential thereof, pixels are selected in units of rows.

Claims

1. A solid-state imaging element, comprising:

unit pixels each of which has a photoelectric conversion element, a transfer switch for transferring charge stored in said photoelectric conversion element and a charge store part for storing charge transferred by said transfer switch;

wherein negative voltage is applied to a gate of said transfer switch for the period during which a charge transfer pulse is not applied to the gate.

2. A solid-state imaging element as claimed in claim 1, wherein a vertical scanning circuit affords vertical selection pulses sequentially output during vertical scanning to a reset switch as a reset potential thereof.

3. A solid-state imaging element as claimed in claim 1, wherein said charge store part is floating diffusion.

4. A solid-state imaging element as claimed in claim 1, further comprising a depression type transistor as a reset transistor.

5. A solid-state imaging element as claimed in claim 1, wherein an output circuit outputs signals read into said vertical signal lines in voltage mode.

6. A solid-state imaging element as claimed in claim 1, wherein an output circuit outputs signals read into said vertical signal lines in current mode.

7. A solid-state imaging element as claimed in claim 1, wherein said unit pixels each include an overflow path between said photoelectric transfer element and an area to which a pixel source voltage is applied, said overflow path being used to discharge excess charges of said photoelectric transfer element.

8. A solid-state imaging element as claimed in claim 1, wherein a negative potential is applied to the control electrode of said transfer switch.

9. A solid-state imaging element as claimed in claim 1, wherein each of said unit pixels include a transfer selection switch for selecting a transfer operation of said transfer switches.

10. A solid-state imaging element as claimed in claim 9, wherein said transfer selection switch makes a controlled input of said vertical selection pulses.

11. A solid-state imaging element as claimed in claim 9, wherein an output circuit outputs signals read into vertical signal lines in current mode.

12-15. -15. (Canceled)