Photoelectric conversion element that reduces a residual image while enhancing heat resistance

Patent metadata

Field	Value
Publication number	US-12063800-B2
Application number	US-202117220747-A
Country	US
Kind code	B2
Filing date	Apr 1, 2021
Priority date	Apr 7, 2020
Publication date	Aug 13, 2024
Grant date	Aug 13, 2024

Abstract

A photoelectric conversion element that reduces a residual image while enhancing heat resistance and includes a first electrode; a photoelectric conversion layer; a first interfacial layer; and a second electrode in this order, the photoelectric conversion layer has a quantum dot, the quantum dot is a PbS quantum dot, the first interfacial layer has an organic compound having a glass transition temperature of 100° ° C. or higher, and the following Equation (1) is met: μhEBL≥1.0×10−3 (cm2/Vs) . . . (1), where μhEBL denotes hole mobility of the first interfacial layer.

First claim

What is claimed is:

1. A photoelectric conversion element comprising:
a first electrode;
a photoelectric conversion layer;
a first interfacial layer; and
a second electrode in this order,
wherein the photoelectric conversion layer has a quantum dot,
wherein the quantum dot is a PbS quantum dot,
wherein the first interfacial layer has an organic compound having a glass transition temperature of 100° C. or higher and including a fluorene moiety, and
wherein the organic compound does not have acceptor substituents;
wherein following Equation (1) is met:
μ h EBL ≥1.0×10 −3 (cm 2 /Vs )  Equation (1),

wherein μh EBL denotes hole mobility of the first interfacial layer.

2. The photoelectric conversion element according to claim 1 , wherein a voltage applied between the first electrode and the second electrode is higher than or equal to 1 V.

3. The photoelectric conversion element according to claim 2 , wherein the quantum dot has a nanoparticle, and the nanoparticle includes PbS, PbSe, PbTe, InP, InAs, CdS, CdSe, or CdTe.

4. The photoelectric conversion element according to claim 1 , wherein the organic compound is at least one of following compounds:

5. The photoelectric conversion element according to claim 1 further comprising a second interfacial layer between the first electrode and the photoelectric conversion layer.

6. The photoelectric conversion element according to claim 5 , wherein the second interfacial layer has titanium oxide or zinc oxide that is an n-type wide band gap semiconductor.

7. The photoelectric conversion element according to claim 1 , wherein the first electrode has titanium or titanium nitride.

8. The photoelectric conversion element according to claim 1 , wherein the quantum dot has a nanoparticle, and a surface of the nanoparticle is coordinated with at least one type of organic ligands selected from 1,4-benzenedithiol and 1,3-benzenedithiol.

9. The photoelectric conversion element according to claim 1 , wherein the quantum dot has a nanoparticle, and at least one type of halogens selected from iodine, chlorine, and bromine is added to a surface of the nanoparticle.

10. The photoelectric conversion element according to claim 1 , further comprising at least one layer selected from a passivation layer, a lens layer, and a color filter layer on the first electrode or the second electrode.

11. An image sensor comprising:
a plurality of pixels; and
a signal processing circuit connected to the pixels, wherein the pixel has the photoelectric conversion element according to claim 1 and a readout circuit connected to the photoelectric conversion element.

12. A light receiving element comprising:
the photoelectric conversion element according to claim 1 ;
a readout circuit that reads charges from the photoelectric conversion element; and
a signal processing circuit that receives charges from the readout circuit and processes a signal.

13. An imaging device comprising:
an optical system having a plurality of lenses; and
a light receiving element that receives light that transmitted through the optical system,
wherein the light receiving element has the photoelectric conversion element according to claim 1 .

14. A moving unit comprising:
a body provided with an imaging device; and
a traveling unit that causes the body to move,
wherein the imaging device is the imaging device according to claim 13 .

15. The photoelectric conversion element according to claim 1 , wherein the organic compound has a triarylamine moiety.

16. The photoelectric conversion element according to claim 1 , wherein the organic compound has two or more amino groups.

Assignees

• Canon Kk

Inventors

• Yamaguchi Tomona
• Sumida Takayuki

Classifications

• H10K30/10

  comprising heterojunctions between organic semiconductors and inorganic semiconductors · CPC title

• H10K39/32 Primary

  Organic image sensors · CPC title

• H10K85/636 Primary

  comprising heteroaromatic hydrocarbons as substituents on the nitrogen atom · CPC title

• H10K85/6572

  comprising only nitrogen in the heteroaromatic polycondensed ring system, e.g. phenanthroline or carbazole · CPC title

• H10K85/633

  comprising polycyclic condensed aromatic hydrocarbons as substituents on the nitrogen atom · CPC title