Photoelectric conversion apparatus and equipment

• US 10,784,299 B2
• Filed: 10/10/2018
• Issued: 09/22/2020
• Est. Priority Date: 10/13/2017
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Hara, Koji, Ogawa, Toshiyuki, Ikeda, Hajime
• Primary Examiner(s): Withers, Grant S
• Application Number:
  US16/156,442
• Publication Number:
  US 20190115383A1
• Time in Patent Office: 713 Days
• CPC Class Codes: H01L 27/14603 Special geometry or disposition of pixel-elements, address-lines or gate-electrodes
• CPC Class Codes: H01L 27/14612 involving a transistor
• CPC Class Codes: H01L 27/14623 Optical shielding
• CPC Class Codes: H01L 27/14643 Photodiode arrays; MOS imagers

Abstract

Provided is a photoelectric conversion apparatus including: an interlayer insulating film that covers a semiconductor layer and has a contact hole positioned above a gate electrode; a contact plug that is disposed in the contact hole and connected to the gate electrode; a light-shielding film that is positioned between the interlayer insulating film and the semiconductor layer and includes a first part covering a charge holding portion and a second part covering an upper surface of the gate electrode; and a dielectric layer that is positioned between the second part and the gate electrode, in which a relative dielectric constant of the dielectric layer is lower than a relative dielectric constant of the interlayer insulating film.

Claims

1. A photoelectric conversion apparatus comprising:

a semiconductor layer that includes a photoelectric conversion portion, a charge holding portion which holds electric charge generated by the photoelectric conversion portion, and a charge detection portion to which the electric charge held by the charge holding portion is transferred;

a gate electrode of a transistor, which is disposed on the semiconductor layer;

an insulator film that covers the semiconductor layer and has a contact hole positioned above the gate electrode;

a contact plug that is disposed in the contact hole and connected to the gate electrode, the contact plug being arranged so as to overlap the gate electrode in a plan view;

a light-shielding film that is positioned between an upper surface of the insulator film and an upper surface of the semiconductor layer and includes a first part covering the charge holding portion and a second part covering the gate electrode; and

a dielectric layer that is positioned between the second part and the gate electrode, wherein

a relative dielectric constant of the dielectric layer is lower than a relative dielectric constant of the insulator film.

2. The photoelectric conversion apparatus according to claim 1, wherein

the gate electrode includes an upper surface and a side surface, the second part covers the upper surface of the gate electrode, and the dielectric layer is positioned between the upper surface of the gate electrode and the second part.

3. The photoelectric conversion apparatus according to claim 2, wherein the gate electrode is connected to the charge detection portion.

4. The photoelectric conversion apparatus according to claim 3, wherein a distance between the first part and the semiconductor layer is shorter than a distance between the second part and the semiconductor layer.

5. The photoelectric conversion apparatus according to claim 4, wherein the charge holding portion includes an n-type semiconductor region, and a p-type semiconductor region is disposed between the n-type semiconductor region and a surface of the semiconductor layer.

6. Electronic equipment that includes the photoelectric conversion apparatus according to claim 5, further comprising at least any one of:

an optical system that forms an image in the photoelectric conversion apparatus;

a control apparatus that controls the photoelectric conversion apparatus;

a processing apparatus that performs processing for a signal output from the photoelectric conversion apparatus;

a display apparatus that displays information obtained by the photoelectric conversion apparatus; and

a memory apparatus that stores information obtained by the photoelectric conversion apparatus.

7. The photoelectric conversion apparatus according to claim 3, wherein the dielectric layer includes an opening above the photoelectric conversion portion.

8. The photoelectric conversion apparatus according to claim 3, wherein a dielectric film that has a relative dielectric constant higher than the relative dielectric constant of the dielectric layer is provided between the dielectric layer and the gate electrode.

9. The photoelectric conversion apparatus according to claim 3, wherein the light-shielding film is provided with a first opening positioned above the photoelectric conversion portion and a second opening positioned above the charge detection portion.

10. The photoelectric conversion apparatus according to claim 9, wherein a plurality of contact plugs that include the contact plug connected to the gate electrode are provided in the second opening.

11. The photoelectric conversion apparatus according to claim 9, wherein the light-shielding film is provided with a third opening, and a plurality of contact plugs that include the contact plug connected to the gate electrode are provided in the third opening.

12. The photoelectric conversion apparatus according to claim 2, wherein

a first transfer electrode is provided on a semiconductor region between the photoelectric conversion portion and the charge holding portion, and a second transfer electrode is provided on a semiconductor region between the charge holding portion and the charge detection portion,

a plurality of pixel circuits that are two dimensionally arrayed, a pixel circuit of the plurality of pixel circuits including the first transfer electrode, the second transfer electrode, and the gate electrode, and

the transistor is connected to the charge detection portion.

13. The photoelectric conversion apparatus according to claim 1, wherein the light-shielding film includes a third part that covers a semiconductor region constituting a source or a drain of the transistor, the dielectric layer extends between the third part and the semiconductor layer, and the semiconductor region is arranged apart from the photoelectric conversion portion and the charge holding portion.

14. The photoelectric conversion apparatus according to claim 13, wherein the light-shielding film includes a fourth part that covers a part of the photoelectric conversion portion, and the dielectric layer extends between the fourth part and the semiconductor layer.

15. The photoelectric conversion apparatus according to claim 13, wherein the semiconductor region functions also as the source or the drain of the transistor othcr than the transistor.

16. The photoelectric conversion apparatus according to claim 1, wherein the insulator film and the dielectric layer include Si and O, and the dielectric layer includes at least one of C and F.

17. The photoelectric conversion apparatus according to claim 1, wherein a wiring layer mainly composed of copper is provided on the light-shielding film, and the main component of the light-shielding film is a metal other than copper.

18. Transfer equipment that includes a moving apparatus, further comprising:

the photoelectric conversion apparatus according to claim 1; and

a processing apparatus that performs processing by which the moving apparatus is operated on a basis of information obtained by the photoelectric conversion apparatus.

19. A photoelectric conversion apparatus comprising:

a semiconductor layer that includes a photoelectric conversion portion, a charge holding portion which holds electric charge generated by the photoelectric conversion portion, and a charge detection portion to which the electric charge held by the charge holding portion is transferred;

a gate electrode of a transistor, which is disposed on the semiconductor layer;

a light-shielding film that is positioned between an upper surface of an insulator film and an upper surface of the semiconductor layer and includes a first part covering the charge holding portion and a second part covering the gate electrode;

a contact plug that is connected to the gate electrode and that is arranged so as to overlap the gate electrode in a plan view; and

a dielectric layer that is positioned between the second part and the gate electrode, wherein

the dielectric layer is formed of a low-k material.

20. The photoelectric conversion apparatus according to claim 19, wherein the dielectric layer is formed of an organic polymer and/or a relative dielectric constant of the dielectric layer is equal to or less than 3.5.

21. A photoelectric conversion apparatus comprising:

a semiconductor layer that includes a photoelectric conversion portion, a charge holding portion which holds electric charge generated by the photoelectric conversion portion, and a charge detection portion to which the electric charge held by the charge holding portion is transferred;

a gate electrode of a transistor, which is disposed on the semiconductor layer;

an insulator film that covers the semiconductor layer and has a contact hole positioned above the gate electrode;

a contact plug that is disposed in the contact hole and connected to the gate electrode, the contact plug being arranged so as to overlap the gate electrode in a plan view;

a light-shielding film that is positioned between an upper surface of the insulator film and an upper surface of the semiconductor layer and includes a first part covering the charge holding portion and a second part covering the gate electrode; and

a dielectric layer that is positioned between the second part and the gate electrode, wherein

the insulator film includes Si and O, and at least one of B and P, and the dielectric layer includes Si and O, and at least one of C and F.

22. Electronic equipment that includes the photoelectric conversion apparatus according to claim 21, further comprising at least any one of:

an optical system that forms an image in the photoelectric conversion apparatus;

a control apparatus that controls the photoelectric conversion apparatus;

a processing apparatus that performs processing for a signal output from the photoelectric conversion apparatus;

a display apparatus that displays information obtained by the photoelectric conversion apparatus; and

a memory apparatus that stores information obtained by the photoelectric conversion apparatus.

23. Transfer equipment that includes a moving apparatus, further comprising:

the photoelectric conversion apparatus according to claim 21; and

a processing apparatus that performs processing by which the moving apparatus is operated on a basis of information obtained by the photoelectric conversion apparatus.