Image pickup apparatus and image pickup system

Patent metadata

Field	Value
Publication number	US-9653622-B2
Application number	US-201313741686-A
Country	US
Kind code	B2
Filing date	Jan 15, 2013
Priority date	Jan 18, 2012
Publication date	May 16, 2017
Grant date	May 16, 2017

Abstract

An image pickup apparatus includes photoelectric conversion units each including a first semiconductor region of a first conductivity type and a semiconductor region of a second conductivity type disposed in contact with the first semiconductor region, a potential barrier formed between photoelectric conversion units, and a contact plug disposed in an image sensing area. The number of contact plugs is smaller than the number of photoelectric conversion units. The photoelectric conversion units include first and second photoelectric conversion units and are arranged such that at least two first photoelectric conversion units are adjacent in a first direction. The potential barrier includes a first part formed between the two first photoelectric conversion units disposed adjacently and a second part formed between first and second photoelectric conversion units adjacent to each other. The contact plug is located closer to the first part than to the second part.

First claim

What is claimed is:

1. An image pickup apparatus comprising:
a plurality of photoelectric conversion units each including a first-conductivity-type first semiconductor region configured to accumulate a signal charge and disposed in contact with a second-conductivity-type semiconductor region;
a potential barrier formed between photoelectric conversion units included in the plurality of photoelectric conversion units; and
a plurality of contact plugs which are disposed in an image sensing area and configured to supply a voltage to the second-conductivity-type semiconductor region, the plurality of photoelectric conversion units being disposed in the image sensing area, wherein
a number of contact plugs is smaller than a number of photoelectric conversion units included in the plurality of photoelectric conversion units,
the plurality of photoelectric conversion units include a first photoelectric conversion unit (PCU) and a second PCU, both configured to receive light of a first color and a third PCU configured to receive light of a second color,
the first, second, and third PCUs are arranged respectively in a line in a first direction,
the first and second PCUs are adjacent to each other in a first direction,
the second and third PCUs are adjacent to each other in the first direction,
the potential barrier includes a first part formed between the first and second PCUs and the potential barrier includes a second part formed between the second and third PCUs, and
a distance from a contact plug of the plurality of contact plugs to the first part of the potential barrier is smaller than a distance from the contact plug to the second part of the potential barrier.

2. The image pickup apparatus according to claim 1 , wherein the contact plug is disposed such that a second direction from a region disposed between the first-conductivity-type first semiconductor regions respectively included in the first and second PCUs toward the contact plug crosses the first direction.

3. The image pickup apparatus according to claim 2 , wherein
a wiring configured to supply the voltage to the contact plug is disposed in the first direction, and not disposed between the first and second PCUs.

4. The image pickup apparatus according to claim 1 , wherein
the second-conductivity-type semiconductor region includes a second-conductivity-type second semiconductor region forming the first part of the potential barrier,
the contact plug is disposed in contact with a second-conductivity-type third semiconductor region,
an isolating insulator unit is disposed between the second semiconductor region and the third semiconductor region, and
the second-conductivity-type semiconductor region continuously extends from the third semiconductor region to a PN junction portion between the first semiconductor region and the second semiconductor region, and is disposed under the isolating insulator unit.

5. The image pickup apparatus according to claim 4 , wherein the first-conductivity-type first semiconductor regions respectively included in the first and second PCUs are electrically connected via a first-conductivity-type semiconductor region disposed below the second semiconductor region.

6. The image pickup apparatus according to claim 1 , wherein the contact plug is disposed in a region where the first part of the potential barrier is formed.

7. The image pickup apparatus according to claim 1 , wherein half or more of the contact plugs included in the plurality of contact plugs are disposed at locations closer to the first part than to the second part.

8. The image pickup apparatus according to claim 1 , wherein every contact plug included in the plurality of contact plugs is disposed at a location closer to the first part than to the second part.

9. The image pickup apparatus according to claim 1 , wherein a length of the first part of the potential barrier as seen in the first direction is smaller than a length of the second part of the potential barrier as seen in the first direction.

10. The image pickup apparatus according to claim 1 , further comprising a plurality of amplifying transistors disposed in the image sensing area, each being configured to output a signal based on an amount of charges generated by a corresponding one of the plurality of photoelectric conversion units, wherein
a second contact plug for supplying a voltage to a drain of the amplifying transistor is disposed at a location closer to the first part than to the second part.

11. The image pickup apparatus according to claim 1 , wherein at least one of a transfer transistor configured to transfer an electric charge from a photoelectric conversion unit, an amplifying transistor configured to amplify the electric charge and output a signal, and a reset transistor configured to reset an input node of the amplifying transistor is disposed between the first and second PCUs.

12. The image pickup apparatus according to claim 1 , further comprising a lattice-shaped electrically conductive material electrically connected to the plurality of contact plugs, wherein
part of the electrically conductive material is disposed on a region between the first and second PCUs.

13. An image pickup system comprising:
the image pickup apparatus according to claim 1 ; and
a signal processing apparatus configured to process a signal output from the image pickup apparatus.

14. The image pickup apparatus according to claim 1 , wherein the first part and the second part are arranged in the first direction.

15. The image pickup apparatus according to claim 1 , wherein
a fourth PCU configured to receive light of the second color,
the first, second, third, and fourth PCUs are arranged respectively in a line in the first direction.

16. An image pickup apparatus comprising:
a plurality of photoelectric conversion units each including a first-conductivity-type first semiconductor region configured to accumulate a signal charge and disposed in contact with second-conductivity-type semiconductor region;
a potential barrier formed between photoelectric conversion units included in the plurality of photoelectric conversion units; and
a plurality of contact plugs which are disposed in an image sensing area and configured to supply a voltage to the second-conductivity-type semiconductor region, the plurality of photoelectric conversion units being disposed in the image sensing area, wherein
a number of contact plugs is smaller than a number of photoelectric conversion units included in the plurality of photoelectric conversion units,
the plurality of photoelectric conversion units include a first photoelectric conversion unit (PCU) and a second PCU, both disposed below a first lens, and a third PCU disposed below a second lens,
the first, second, and third PCUs are arranged respectively in a line in a first direction,
the first and second PCUs are adjacent to each other in a first direction,
the second and third PCUs are adjacent to each other in the first direction,
the potential barrier includes a first part formed between the first and second PCUs, and a second part formed between the second and third PCUs, and
a distance from a contact plug of the plurality of contact plugs to the first part of the potential barrier is smaller than the distance from the contact plug to the second part of the potential barrier.

17. An image pickup system comprising:
the image pickup apparatus according to claim 16 ; and
a signal processing apparatus configured to process a signal output from the image pickup apparatus.

18. The im

Assignees

• Canon Kk

Inventors

• Johnson Michiko
• Kobayashi Masahiro
• Wada Yoichi
• Tsuboi Hiromasa

Classifications

• H01L27/14645

  Electricity · mapped topic

• H01L31/0232

  Electricity · mapped topic

• H01L31/02002 Primary

  Electricity · mapped topic

• H01L27/14605

  Electricity · mapped topic

• H01L27/14601

  Electricity · mapped topic