IMAGE SENSOR AND ELECTRONIC CAMERA

• US 20180278860A1
• Filed: 09/27/2016
• Published: 09/27/2018
• Est. Priority Date: 09/30/2015
• Status: Active Grant

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: SARUWATARI, Osamu, KATO, Shutaro, ANDO, Ryoji, TEZUKA, Yojiro, KOMAI, Atsushi
• Granted Patent: US 10,944,924 B2
• Time in Patent Office: Days
• CPC Class Codes: H01L 27/14634 Assemblies, i.e. Hybrid structures
• CPC Class Codes: H01L 27/1464 Back illuminated imager structures
• CPC Class Codes: H01L 27/14643 Photodiode arrays; MOS imagers
• CPC Class Codes: H01L 27/1469 Assemblies, i.e. hybrid integration
• CPC Class Codes: H04N 25/53 Control of the integration time
• CPC Class Codes: H04N 25/63 applied to dark current
• CPC Class Codes: H04N 25/70 SSIS architectures; Circuits associated therewith
• CPC Class Codes: H04N 25/75 Circuitry for providing, modifying or processing image signals from the pixel array
• CPC Class Codes: H04N 25/766 comprising control or output lines used for a plurality of functions, e.g. for pixel output, driving, reset or power
• CPC Class Codes: H04N 25/77 Pixel circuitry, e.g. memories, A/D converters, pixel amplifiers, shared circuits or shared components

Abstract

An image sensor includes a first semiconductor substrate provided with a pixel, including a photoelectric conversion unit that photoelectrically converts incident light to generate an electric charge, an accumulation unit that accumulates the electric charge generated by the photoelectric conversion unit, and a transfer unit that transfers the electric charge generated by the photoelectric conversion unit to the accumulation unit, and a second semiconductor substrate provided with a supply unit for the pixel, the supply unit supplying the transfer unit with a transfer signal to transfer the electric charge from the photoelectric conversion unit to the accumulation unit.

Claims

1. An image sensor comprising:

a first semiconductor substrate provided with a pixel, including a photoelectric conversion unit that photoelectrically converts incident light to generate an electric charge, an accumulation unit that accumulates the electric charge generated by the photoelectric conversion unit, and a transfer unit that transfers the electric charge generated by the photoelectric conversion unit to the accumulation unit; and

a second semiconductor substrate provided with a supply unit for the pixel, the supply unit supplying the transfer unit with a transfer signal to transfer the electric charge from the photoelectric conversion unit to the accumulation unit.

2. The image sensor according to claim 1, wherein:

a first substrate voltage applied to the first semiconductor substrate and a second substrate voltage applied to the second semiconductor substrate are different from each other.

3. The image sensor according to claim 2, wherein:

the supply unit includes a first power supply unit and a second power supply unit; and

at least one of the first power supply unit and the second power supply unit is provided in the second semiconductor substrate.

4. The image sensor according to claim 3, wherein:

the first power supply unit supplies a first voltage higher than the first substrate voltage; and

the second power supply unit supplies a second voltage lower than the first substrate voltage.

5. The image sensor according to claim 4, wherein:

the transfer unit electrically connects the photoelectric conversion unit and the accumulation unit and transfers the electric charge generated by the photoelectric conversion unit to the accumulation unit; and

the supply unit supplies the transfer unit with the transfer signal for electrically connecting or disconnecting the photoelectric conversion unit and the accumulation unit.

6. The image sensor according to claim 4, wherein:

the transfer unit electrically connects the photoelectric conversion unit and the accumulation unit if the first voltage is supplied as the transfer signal, and electrically disconnects the photoelectric conversion unit and the accumulation unit if the second voltage is supplied as the transfer signal.

7. The image sensor according to claim 4, wherein:

the supply unit supplies the transfer signal for transferring the electric charge generated by the photoelectric conversion unit during a first period to the accumulation unit or the transfer signal for transferring the electric charge generated by the photoelectric conversion unit during a second period to the accumulation unit, the second period having a length different from that of the first period.

8. The image sensor according to claim 7, wherein:

an end time of the first period is the same as an end time of the second period.

9. The image sensor according to claim 4, wherein:

one of the first voltage and the second voltage is the second substrate voltage.

10. The image sensor according to claim 4, further comprising:

a first reset unit that is provided in the first semiconductor substrate and resets an electrical charge accumulated in the accumulation unit based on a reset signal;

a reset signal supply unit that is provided in a semiconductor substrate different from the second semiconductor substrate and supplies the first reset unit with either a third voltage not less than the first substrate voltage or a fourth voltage higher than the third voltage as the reset signal.

11. The image sensor according to claim 10, wherein:

one of the third voltage and the fourth voltage is the first substrate voltage.

12. The image sensor according to claim 10, further comprising:

a third semiconductor substrate to which the first substrate voltage is applied, wherein;

the reset signal supply unit is provided in the third semiconductor substrate.

13. The image sensor according to claim 1, comprising:

the plurality of pixels wherein;

the supply unit included in one of a part of the plurality of pixels supplies the transfer signal for transferring the electric charge generated by the photoelectric conversion unit during a first period to the accumulation unit and the supply unit included in one of another part of the plurality of pixels supplies the transfer signal for transferring the electric charge generated by the photoelectric conversion unit during a second period to the accumulation unit, the second period having a length different from that of the first period.

15. The image sensor according to claim 1, further comprising:

an A/D conversion unit that performs an analog/digital conversion on an analog signal based on an amount of electric charge accumulated in the accumulation unit, by a correlated multiplex sampling process.

16. The image sensor according to claim 1, further comprising:

a second reset unit that resets the electric charge accumulated in the photoelectric conversion unit.

17. The image sensor according to claim 1, wherein:

the photoelectric conversion unit is a pinned photodiode.

18. An electronic camera comprising the image sensor according to claim 1.

14. An image sensor comprising:

a photoelectric conversion unit that photoelectrically converts incident light to generate an electric charge;

a transfer unit that transfers an electric charge generated by the photoelectric conversion unit to an accumulation unit based on a transfer signal;

a transfer signal supply unit that supplies the transfer unit with the transfer signal;

a first reset unit that resets the electric charge accumulated in the accumulation unit based on a reset signal;

a reset signal supply unit that supplies the first reset unit with the reset signal;

a first semiconductor substrate provided with the photoelectric conversion unit, the transfer unit, and the first reset unit; and

a second semiconductor substrate provided with the reset signal supply unit arranged in a first diffusion layer and the transfer signal supply unit arranged in a second diffusion layer having a polarity different from that of the first diffusion layer.