JP2015153911A - Photoelectric conversion element, photosensor and imaging element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a photoelectric conversion element exhibiting excellent low dark current properties, rapid response, heat resistance and production suitability; and an imaging element and a photosensor including the photoelectric conversion element.SOLUTION: A photoelectric conversion element includes: a conductive film; a transparent conductive film; a photoelectric conversion film and an electron blocking film which are disposed between the conductive film and the transparent conductive film. The electron blocking film includes at least one compound selected from the group consisting of a compound A represented by formula (A) and having a molecular weight of 550-900, a compound B represented by formula (B) and having a molecular weight of 650-950, and a compound C represented by formula (C) and having a molecular weight of 800-950. Formula (A) Z-(R). Formula (B) (R)-Y-Y-(R).

Description

  The present invention relates to a photoelectric conversion element, an optical sensor, and an imaging element.

  A conventional optical sensor is an element in which a photodiode (PD) is formed in a semiconductor substrate such as silicon (Si). As a solid-state image sensor, signal charges generated in each PD are arranged in two dimensions. Are widely used.

  In order to realize a color solid-state imaging device, a structure in which a color filter that transmits light of a specific wavelength is arranged on the light incident surface side of the flat solid-state imaging device is generally used. Color filters that transmit blue (B) light, green (G) light, and red (R) light are regularly arranged on each two-dimensionally arranged PD that is currently widely used in digital cameras and the like. Single-plate solid-state imaging devices are well known.

  In recent years, development of solid-state imaging devices having a structure in which an organic photoelectric conversion film is formed on a signal readout substrate has been advanced. In solid-state imaging devices and photoelectric conversion devices using such an organic photoelectric conversion film, a technique for introducing an electron blocking film for the purpose of suppressing dark current is known (for example, Patent Document 1).

JP 2011-176259 A

In recent years, there has been a demand for further noise reduction and responsiveness improvement for image sensors and photosensors. Accordingly, various characteristics (particularly, low dark current characteristics and high-speed responsiveness) are required for the photoelectric conversion elements used for them. There is a need for further improvements.
Moreover, when applying a photoelectric conversion element to various uses, such as an image pick-up element and an optical sensor, it is calculated | required that a photoelectric conversion element shows high heat resistance from the point of process suitability. For example, as a process for forming an image sensor, there are many processes for performing heat treatment such as color filter installation, protective film installation, element soldering, and the photoelectric conversion element has excellent characteristics ( (Low dark current property, high speed response) is required. In recent years, lead-free solder has been widely used due to environmental considerations, and heat treatment at a higher temperature than the conventional lead-containing solder process is required. Therefore, the photoelectric conversion element is required to have higher heat resistance than ever.
Furthermore, with the demand for cost reduction of various devices in which photoelectric conversion elements are used, it is important to manufacture the photoelectric conversion elements with higher productivity. In general, the electron blocking film in the photoelectric conversion element is manufactured by vapor deposition or the like, but it is desirable that a performance difference does not occur between lots of manufactured photoelectric conversion elements. That is, in a production line for forming an electron blocking film by a vapor deposition process, once the electron blocking material is placed in a vapor deposition apparatus and continuous vapor deposition is performed, the photoelectric conversion element produced in the early stage of production and the late production stage are produced. It is desirable that there is no difference in each characteristic (particularly dark current property and responsiveness) with the photoelectric conversion device, that is, a photoelectric conversion device excellent in manufacturing suitability.

  The inventors of the present invention made a photoelectric conversion element using the electron blocking material disclosed in Patent Document 1, and in the obtained photoelectric conversion element, a dark current was applied by a heat treatment with a larger load than before. Or, the response speed was greatly deteriorated, and it became clear that it does not satisfy the demand for heat resistance recently required. Moreover, also in the point of manufacture aptitude, it did not necessarily reach the level requested | required these days, but it discovered that the further improvement was required.

An object of this invention is to provide the photoelectric conversion element which shows the outstanding low dark current property, high-speed response property, heat resistance, and manufacture aptitude in view of the said situation.
Another object of the present invention is to provide an optical sensor and an imaging element including a photoelectric conversion element.

As a result of intensive studies on the above problems, the present inventors have found that the above problems can be solved by using an electron blocking film containing a predetermined electron blocking material, and have completed the present invention.
That is, the above problems can be solved by the following means.

(1) A photoelectric conversion element having a conductive film, a transparent conductive film, and a photoelectric conversion film and an electron blocking film disposed between the conductive film and the transparent conductive film,
The electron blocking film is represented by the formula (A) described later, the compound A having a molecular weight of 550 to 900, the compound B represented by the formula (B) described later, and the molecular weight of 650 to 950, and a formula described later. A photoelectric conversion device comprising at least one compound selected from the group consisting of compound C represented by (C) and having a molecular weight of 800 to 950.
(2) The photoelectric conversion element according to (1), wherein the partial structure represented by Formula (1) is a partial structure represented by Formula (2) described later.
(3) at least one compound is compound C;
In formula (C), Ya is a condensed polycyclic aromatic hydrocarbon group, and Yb and Yc are each independently a condensed polycyclic aromatic heterocyclic group containing a partial structure represented by formula (1). The photoelectric conversion element as described in 1) or (2).
(4) The photoelectric conversion element according to any one of (1) to (3), wherein at least one compound is represented by formula (R) described later and has a molecular weight of 800 to 950.
(5) The photoelectric conversion element according to any one of (1) to (4), wherein the photoelectric conversion film contains a compound represented by the formula (W) described later.
(6) The photoelectric conversion element according to (5), wherein the compound represented by the formula (W) is a compound represented by the formula (W1) described later.
(7) The photoelectric conversion element according to (5) or (6), wherein the compound represented by the formula (W) is a compound represented by the formula (W2) described later.
(8) The photoelectric conversion element according to any one of (1) to (7), wherein the photoelectric conversion film further contains an organic n-type compound.
(9) The photoelectric conversion element according to (8), wherein the organic n-type compound contains fullerenes selected from the group consisting of fullerenes and derivatives thereof.
(10) The photoelectric conversion element according to any one of (1) to (9), wherein light is incident on the photoelectric conversion film via a transparent conductive film.
(11) The photoelectric conversion element according to any one of (1) to (10), wherein the transparent conductive film is made of a transparent conductive metal oxide.
(12) An optical sensor comprising the photoelectric conversion element according to any one of (1) to (11).
(13) An imaging device including the photoelectric conversion device according to any one of (1) to (11).

ADVANTAGE OF THE INVENTION According to this invention, the photoelectric conversion element which shows the outstanding low dark current property, high-speed response property, heat resistance, and manufacture aptitude can be provided. Moreover, according to this invention, the image pick-up element containing a photoelectric conversion element And an optical sensor can be provided.

FIG. 1A and FIG. 1B are schematic cross-sectional views each showing a configuration example of a photoelectric conversion element. It is a cross-sectional schematic diagram for 1 pixel of an image pick-up element.

Below, the suitable embodiment of the photoelectric conversion element of this invention is demonstrated.
One of the features compared with the prior art of the present invention is that an electron blocking material having a predetermined structure is used. First, in the compound used as the electron blocking material, the condensed polycyclic aromatic heterocyclic group containing the partial structure represented by the formula (1) (particularly the carbazole ring group) is contained, thereby reducing dark current and Effective for improving response performance. In addition, when a non-aromatic group is introduced into a condensed polycyclic aromatic hydrocarbon group and a condensed polycyclic aromatic heterocyclic group, it is also effective in suppressing crystallization of the compound, contributing to the improvement of the above characteristics. Yes. Furthermore, the response performance is improved by controlling the content of the condensed polycyclic aromatic hydrocarbon group and the condensed polycyclic aromatic heterocyclic group contained in the compound.
Further, according to the study of the present inventors, it is effective to increase the molecular weight of the compound used in order to maintain low dark current property and high-speed response even after high temperature treatment, that is, to exhibit excellent heat resistance. I understood it. On the other hand, an increase in the molecular weight causes an increase in sublimation temperature, and an increase in the sublimation temperature causes decomposition of the compound, which raises a concern that a difference in performance between lots of photoelectric conversion elements may occur. In other words, it was also found that heat resistance and manufacturing suitability are in a trade-off relationship. Therefore, by controlling the molecular weight of the whole compound and the content of the condensed polycyclic aromatic hydrocarbon group and the condensed polycyclic aromatic heterocyclic group contained in the compound that suppress the decomposition of the compound, Improved manufacturing suitability has been achieved.

Below, the suitable embodiment of the photoelectric conversion element of this invention is demonstrated with reference to drawings. In FIG. 1, the cross-sectional schematic diagram of one Embodiment of the photoelectric conversion element of this invention is shown.
A photoelectric conversion element 10a shown in FIG. 1A includes a conductive film (hereinafter also referred to as a lower electrode) 11 that functions as a lower electrode, an electron blocking film 16A formed on the lower electrode 11, and an electron blocking film 16A. The photoelectric conversion film 12 formed above and a transparent conductive film (hereinafter also referred to as an upper electrode) 15 functioning as an upper electrode are stacked in this order.
FIG. 1B shows a configuration example of another photoelectric conversion element. The photoelectric conversion element 10b shown in FIG. 1B has a configuration in which an electron blocking film 16A, a photoelectric conversion film 12, a hole blocking film 16B, and an upper electrode 15 are laminated on the lower electrode 11 in this order. Have. Note that the stacking order of the electron blocking film 16A, the photoelectric conversion film 12, and the hole blocking film 16B in FIGS. 1A and 1B may be reversed depending on the application and characteristics. For example, the positions of the electron blocking film 16A and the photoelectric conversion film 12 may be reversed.

In the configuration of the photoelectric conversion element 10 a (10 b), it is preferable that light is incident on the photoelectric conversion film 12 through the transparent conductive film 15.
Moreover, when using the photoelectric conversion element 10a (10b), an electric field can be applied. In this case, it is preferable that the conductive film 11 and the transparent conductive film 15 form a pair of electrodes, and an electric field of 1 × 10 ⁻⁵ to 1 × 10 ⁷ V / cm is applied between the pair of electrodes. From the viewpoint of performance and power consumption, an electric field of 1 × 10 ⁻⁴ to 1 × 10 ⁶ V / cm is preferable, and an electric field of 1 × 10 ^{−3 to} 5 × 10 ⁵ V / cm is particularly preferable.
In addition, about the electric field application method, in FIG. 1 (a) and (b), it is preferable to apply so that the electron blocking film | membrane 16A side may become a cathode and the photoelectric converting film 12 side may become an anode. When the photoelectric conversion element 10a (10b) is used as an optical sensor, or when it is incorporated in an imaging element, an electric field can be applied by the same method.

Below, the aspect of each layer (an electron blocking film, a photoelectric conversion film, an electrode, a hole blocking film, etc.) which comprises the photoelectric conversion element of this invention is explained in full detail.
First, the electron blocking film will be described in detail.

[Electron blocking film]
The electron blocking film of the photoelectric conversion element of the present invention is a layer disposed between a transparent conductive film and a conductive film, which will be described later, and at least one selected from the group consisting of compounds A to C described later. Contains two compounds (hereinafter also referred to as specific compounds).
Below, compound A-compound C are explained in full detail first.

(Compound A)
Compound A is a compound represented by the formula (A).
Formula (A) Z- (R) _n
Compound A has a molecular weight of 550 to 900, and is superior in at least one of low dark current property, high-speed response, heat resistance, and production suitability of the photoelectric conversion element (hereinafter simply referred to as “the effect of the present invention”). 580 to 900 are preferable, and 600 to 850 are more preferable.
When the molecular weight of Compound A is less than 550, the heat resistance is poor.
When the molecular weight of Compound A exceeds 900, the vapor deposition temperature becomes high, which tends to cause thermal decomposition and lacks suitability for production.

  In formula (A), Z represents a condensed polycyclic aromatic heterocyclic group containing the partial structure represented by formula (1).

In the formula (1), X ₁ represents N (X ₃ ). X ₃ represents a bond. The bond represents a bond with another atom contained in the condensed polycyclic aromatic heterocyclic group. For example, a bond indicated by an arrow in the following structural formula corresponds to a bond.

X ₂ each independently represents a nitrogen atom or C (X ₄ ), and X ₄ represents a bond or a hydrogen atom.
Incidentally, in that the effect of the present invention more excellent, it is preferable that all X ₂ is C (X _4). That is, the partial structure represented by the formula (2) is preferable. In addition, the condensed polycyclic aromatic heterocyclic group including a partial structure represented by the following formula (2) is, in other words, a condensed polycyclic aromatic heterocyclic group including a carbazole ring.

The condensed polycyclic aromatic heterocyclic group containing the partial structure represented by the above formula (1) is a partial structure represented by the above formula (1), wherein a plurality of ring structures are condensed to exhibit aromaticity. Is a group containing
Especially, as a suitable aspect of Z, it is represented by the group represented by the following formula (Q1), the group represented by the formula (Q2), or the formula (Q3) in that the effect of the present invention is more excellent. Group. In Formula (Q1) and Formula (Q3), R ₅₁ represents C (R ₅₄ ) (R ₅₅ ), an oxygen atom, a sulfur atom, or N (R ₅₆ ). Among these, C (R ₅₄ ) (R ₅₅ ) is preferable in that the effect of the present invention is more excellent.
R ₅₄ and R ₅₅ each independently represent a bond or a hydrogen atom. R ₅₆ represents a bond. In addition, when any of R _{54 to} R ₅₆ is a bond, a non-aromatic group represented by R described later is bonded thereto.
R ₅₇ represents a single bond, C (R ₅₄ ) (R ₅₅ ), an oxygen atom, a sulfur atom, or N (R ₅₆ ). Among these, from the viewpoint of dark current, R ₅₇ is preferably a single bond or C (R ₅₄ ) (R ₅₅ ), and more preferably a single bond.
The definitions of R _{54 to} R ₅₆ are as described above.
In the formula (Q3), ** represents a bonding position with R.
In addition, when R mentioned later substitutes (when n is 1 or more), what is necessary is just to substitute instead of the hydrogen atom in Formula (Q1)-Formula (Q3).

R represents a non-aromatic group. A non-aromatic group is a group that does not exhibit aromaticity, such as an aliphatic hydrocarbon group (for example, an alkyl group, a cycloalkyl group, an alkenyl group, an alkynyl group), a halogen atom (for example, a fluorine atom, a bromine atom). ), Alkoxy group, cyano group, alkylamino group, hydroxy group, nitro group, carboxy group, carboxylic acid ester group, silyloxy group, acyloxy group, carbamoyloxy group, alkoxycarbonyloxy group, amino group, ammonio group, acylamino group, Aminocarbonylamino group, alkoxycarbonylamino group, sulfamoylamino group, alkylsulfonylamino group, mercapto group, alkylthio group, sulfamoyl group, sulfo group, alkylsulfinyl group, alkylsulfonyl group, acyl group, alkoxycarbonyl group, carbamoyl Imide group, phosphino group, phosphinyl group, phosphinyloxy group, phosphinylamino group, phosphono group, silyl group (for example, trimethylsilyl group, triethylsilyl group, tertiary butyldimethylsilyl group), hydrazino group, ureido group , Boronic acid groups (—B (OH) ₂ ), phosphato groups (—OPO (OH) ₂ ), sulfato groups (—OSO ₃ H), and the like. Among them, an aliphatic hydrocarbon group, an alkoxy group, and a silyl group substituted with an alkyl group are preferable, and an aliphatic hydrocarbon group, an alkoxy group, and a silyl group having a molecular weight of 75 or less are more preferable, particularly a tertiary butyl group and a trimethylsilyl group. And a tertiary butyl group is most preferred. When the molecular weight of R is less than 75, the possibility of causing a decrease in heat resistance and a decrease in responsiveness decreases, which is preferable.
n represents 0 or an integer of 1 or more. When n is plural (two or more), the non-aromatic groups may be the same or different. Although the value of n is not particularly limited, it is preferably 0 to 15 and more preferably 2 to 10 because the effects of the present invention are more excellent.

The ratio of the molecular weight of Z to the total molecular weight of compound A is 50% by mass or more, and 55% by mass or more is preferable and 60% by mass or more is more preferable in that the effect of the present invention is more excellent. The upper limit is not particularly limited, but is preferably 90% by mass or less from the viewpoint of ease of synthesis and response performance.
When the said ratio is less than 50 mass%, the fall of response performance will be caused.
In addition, the molecular weight of said Z intends the molecular weight of the condensed polycyclic aromatic heterocyclic group represented by Z. The ratio of the molecular weight of Z to the total molecular weight of compound A is the total molecular weight of compound A (expressed by the molecular weight of Z and n Rs) of the molecular weight of the condensed polycyclic aromatic heterocyclic group represented by Z. Intended as a percentage of the total molecular weight of non-aromatic groups. More specifically, for example, when the molecular weight of the condensed polycyclic aromatic heterocyclic group represented by Z is 400 and the total molecular weight of the compound A is 800, the ratio of Z to the compound A is (400 / 800) × 100 = 50% by mass.

(Compound B)
Compound B is a compound represented by the formula (B).
Formula (B) (R) _n -YY- (R) _n
The molecular weight of Compound B is 650 to 950, and 700 to 950 is preferable and 800 to 900 is more preferable in that the effect of the present invention is more excellent.
When the molecular weight of Compound B is less than 650, the heat resistance is poor.
When the molecular weight of the compound B is more than 950, the deposition temperature becomes high, the thermal decomposition tends to occur, and the production suitability is lacked.

Y each independently represents a condensed polycyclic aromatic hydrocarbon group or a condensed polycyclic aromatic heterocyclic group.
The condensed polycyclic aromatic hydrocarbon group is a group exhibiting aromaticity by condensation of at least two or more rings. This group has a coplanar structure. Examples of the condensed polycyclic aromatic hydrocarbon group include naphthalene ring group, anthracene ring group, phenanthrene ring group, pyrene ring group, fluorene ring group, azulene ring group, chrysene ring group, perylene ring group, triphenylene ring group, pentalene. Examples thereof include a ring group, an indacene ring group, a fluoranthene ring group, an acephenanthrylene ring group, an aceanthrylene ring group, a naphthacene ring group, a pentaphen ring group, a pentacene ring group, and a hexaphen ring group. A spirofluorene ring is counted as two linked polycyclic aromatic hydrocarbon groups (fluorene groups) linked together.
The condensed polycyclic aromatic heterocyclic group is a group that contains a hetero atom as a ring constituent atom and exhibits aromaticity by condensation of at least two or more rings. Examples of the condensed polycyclic aromatic heterocyclic group include a carbazole ring group, an indazole ring group, a benzimidazole ring group, a benzoxazole ring group, a benzoisoxazole ring group, a benzothiazole ring group, a benzoisothiazole ring group, and a benzotriazole. Ring group, benzooxadiazole ring group, benzothiadiazole ring group, phenanthridine ring group, quinoline ring group, benzoquinoline ring group, isoquinoline ring group, benzoisoquinoline ring group, phenanthroline ring group, quinoxaline ring group, quinazoline ring group Cinnoline ring group, phenazine ring group, perimidine ring group, xanthene ring group, benzofuran ring group, dibenzofuran ring group, benzothiophene ring group, dibenzothiophene ring group and the like.
In the present invention, when a condensed polycyclic aromatic hydrocarbon group such as 9,9-dimethylfluorene has a methyl group as a substituent (particularly, a connecting chain portion connecting benzene rings), these two methyl groups Is treated as a non-aromatic group, and the 9-position carbon atom connecting the two benzene rings to form a fluorene ring or the like is treated as a part of the condensed polycyclic aromatic hydrocarbon group.

In addition, at least one of Y represents a condensed polycyclic aromatic heterocyclic group containing the partial structure represented by the formula (1). In addition, both two Y may be a condensed polycyclic aromatic heterocyclic group including the partial structure represented by the formula (1).
The definition of the condensed polycyclic aromatic heterocyclic group including the partial structure represented by the formula (1) is as described above. In the compound B, as a suitable aspect of the condensed polycyclic aromatic heterocyclic group containing the partial structure represented by the formula (1) represented by Y, a group represented by the formula (S1), a formula (S2) , A group represented by the formula (S3), or a group represented by the formula (S4). That is, at least one of the two Y is a group represented by the formula (S1), a group represented by the formula (S2), a group represented by the formula (S3), and the formula (S4). It is preferably a group selected from the group consisting of groups represented by: In the formula (S1) to the formula (S4), * indicates a connection position with the other Y in the formula (1). In the formulas (S1) to (S4), the definitions of R ₅₁ and R ₅₇ are as described above. In the formula (S4), ** represents a bonding position with R.
When R is substituted (when n is 1 or more), substitution may be performed instead of the hydrogen atom in formula (S1) to formula (S4).

Each R independently represents a non-aromatic group. The definition of the non-aromatic group is as described above.
n independently represents an integer of 0 or 1 or more. When n is plural (two or more), the non-aromatic groups may be the same or different. Although the value of n is not particularly limited, it is preferably 0 to 15 and more preferably 2 to 10 because the effects of the present invention are more excellent.

The ratio of the total molecular weight of two Y in compound B to the total molecular weight of compound B is 50% by mass or more, and 55% by mass or more is preferable and 60% by mass or more is more preferable in that the effect of the present invention is more excellent. preferable. The upper limit is not particularly limited, but is preferably 90% by mass or less from the viewpoint of ease of synthesis and response performance.
When the said ratio is less than 50 mass%, the fall of response performance will be caused.

(Compound C)
Compound C is a compound represented by the formula (C).

The molecular weight of Compound C is 800 to 950, and 825 to 950 are preferable and 850 to 950 are more preferable in that the effect of the present invention is more excellent.
When the molecular weight of Compound C is less than 800, the heat resistance is poor.
When the molecular weight of Compound C exceeds 950, the vapor deposition temperature is high, thermal decomposition is likely to occur, and production suitability is lacking.

Ya, Yb and Yc each independently represent a condensed polycyclic aromatic hydrocarbon group or a condensed polycyclic aromatic heterocyclic group. The definitions of the condensed polycyclic aromatic hydrocarbon group and the condensed polycyclic aromatic heterocyclic group are as described above.
In addition, at least one of Ya, Yb, and Yc represents a condensed polycyclic aromatic heterocyclic group including a partial structure represented by Formula (1).
In addition, the definition of the condensed polycyclic aromatic heterocyclic group containing the partial structure represented by Formula (1) is as above-mentioned. In compound C, Yb and Yc are a condensed polycyclic aromatic heterocyclic group containing a partial structure represented by formula (1). Preferred examples of the group represented by formula (S1) are described above. A group represented by the formula (S2), a group represented by the formula (S3), a group represented by the formula (S4), a group represented by the following formula (T1), and a formula (T2). And a group represented by the formula (T3). * Indicates the position of connection to Ya. In the following formulae, the definitions of R ₅₁ and R ₅₇ are as described above. In the formula (T3), ** represents a bonding position with R.
When R is substituted (when n is 1 or more), it may be substituted for a hydrogen atom in each group (formula (S1) to (S4), formula (T1) to formula (T3)). .

  Examples of Ya include a group represented by the following formula (P1) to a group represented by the formula (P6). Among these, a condensed polycyclic aromatic hydrocarbon group is preferable in that the effect of the present invention is more excellent.

The definition of R ₅₁ in formula (P1), formula (P2), and formula (P5) is as described above.
* In the formulas (P1) to (P6) represents a bonding position with Yb and Yc.
When R is substituted (when n is 1 or more), each group (formulas (P1) to (P6) may be substituted instead of a hydrogen atom).

Each R independently represents a non-aromatic group. The definition of the non-aromatic group is as described above.
n independently represents an integer of 0 or 1 or more. When n is plural (two or more), the non-aromatic groups may be the same or different. Although the value of n is not particularly limited, it is preferably 0 to 15 and more preferably 2 to 10 because the effects of the present invention are more excellent.

The ratio of the total molecular weight of Ya, Yb, and Yc in compound C to the total molecular weight of compound C is 50% by mass or more, and 55% by mass or more is preferable and 60% by mass or more is preferable in that the effect of the present invention is more excellent. Is more preferable. The upper limit is not particularly limited, but is preferably 90% by mass or less from the viewpoint of ease of synthesis and response performance.
When the ratio is less than 50% by mass, the response performance is lowered.

(Preferred embodiment)
As a suitable aspect of the said specific compound, the compound R whose molecular weight is 800-950 represented by Formula (R) is mentioned by the point which the effect of this invention is more excellent. As will be described later, the ratio of the total molecular weight of Y1 and two Y2 to the total molecular weight of Compound R is 50% by mass or more. n independently represents an integer of 0 or 1 or more. Although the value of n is not particularly limited, it is preferably 0 to 15 and more preferably 2 to 10 because the effects of the present invention are more excellent.
Each R independently represents a non-aromatic group. The definition of the non-aromatic group is as described above.

  In formula (R), Y1 represents a group represented by formula (K1), a group represented by formula (K2), a group represented by formula (K3), and a group represented by formula (K4). Any one selected from the group consisting of

In formulas (K1) and (K2), R ₁₀₁ independently represents C (R ₁₀₂ ) (R ₁₀₃ ), an oxygen atom, a sulfur atom, or N (R ₁₀₄ ). Among these, C (R ₁₀₂ ) (R ₁₀₃ ) is preferable in that the effect of the present invention is more excellent.
R ₁₀₂ and R ₁₀₃ each independently represent a hydrogen atom or a bond. R ₁₀₄ represents a bond. Note that when any of R _{102 to} R ₁₀₄ is a bond, the bond is bonded to a non-aromatic group represented by R. That is, R is bonded to one end of the bond represented by R _{102 to} R ₁₀₄ .
* Indicates a binding position with Y2.

  In formula (R), Y2 is each independently selected from the group consisting of a group represented by formula (L1), a group represented by formula (L2), and a group represented by formula (L3). Any one of them. Two Y2s may be the same or different, but are preferably the same.

In formula (L1), R _{61 to} R ₆₈ each independently represent a hydrogen atom or a bond. In addition, when any of R _{61 to} R ₆₈ is a bond, the bond is bonded to a non-aromatic group represented by R. That is, R is bonded to one end of the bond represented by R _{61 to} R ₆₈ .
In addition, it is preferable that at least two of R _{61 to} R ₆₈ are bonds, and an alkyl group having 3 to 5 carbon atoms represented by R is bonded to the bonds in terms of more excellent effects of the present invention. R ₆₃ and R ₆₆ are bonds, and it is more preferable that an alkyl group having 3 to 5 carbon atoms represented by R is bonded to the bond.
* Indicates a binding position with Y1.

In formula (L2), R _{71 to} R ₇₆ each independently represent a hydrogen atom or a bond. In addition, when any of R _{71 to} R ₇₆ is a bond, the bond is bonded to a non-aromatic group represented by R. That is, R is bonded to one end of the bond represented by R _{71 to} R ₇₆ .
Note _that either one _{R 72} of _{R 71,} directly, _{or, C (R 102) (R} 103), an oxygen atom, a sulfur atom, or via a linking group represented by _{N (R 104)} They may combine to form a ring.
R ₁₀₅ represents a single bond, or C (R ₁₀₂ ) (R ₁₀₃ ), an oxygen atom, a sulfur atom, or N (R ₁₀₄ ). Among these, from the viewpoint of dark current, R ₁₀₅ is preferably a single bond or C (R ₁₀₂ ) (R ₁₀₃ ), and more preferably a single bond.
Definition of R ₁₀₂ to R ₁₀₄ are as described above.
a represents 3 or 4, b represents 2 or 3, and a + b = 6. A plurality of R ₇₁ and R ₇₆ may be the same or different.
* Indicates a binding position with Y1.
** is bonded to the benzene ring to which R ₇₁ is bonded when a is 3, and is bonded to the benzene ring to which R ₇₆ is bonded when a is 4. More specifically, when a is 3, the group represented by the formula (L2) corresponds to the group represented by the following formula (L2-1), and when a is 4, The group represented by 2) corresponds to the group represented by the formula (L2-2).

In addition, it is preferable that at least two of R _{72 to} R ₇₆ are bonds, and an alkyl group having 3 to 5 carbon atoms represented by R is bonded to the bonds in terms of more excellent effects of the present invention. R ₇₄ and R ₇₆ are bonds, and it is more preferable that an alkyl group having 3 to 5 carbon atoms represented by R is bonded to the bond.

In formula (L3), R _{81 to} R ₉₂ each independently represent a hydrogen atom or a bond. When any of R _{81 to} R ₉₂ is a bond, the bond is bonded to a non-aromatic group represented by R. That is, R is bonded to one end of the bond represented by R _{81 to} R ₉₂ .
R ₁₀₁ independently represents C (R ₁₀₂ ) (R ₁₀₃ ), an oxygen atom, a sulfur atom, or N (R ₁₀₄ ). Among these, C (R ₁₀₂ ) (R ₁₀₃ ) is preferable in that the effect of the present invention is more excellent.
Definition of R ₁₀₂ to R ₁₀₄ are as described above.
* Indicates a binding position with Y1.

In the compound R, the ratio of the total molecular weight of Y1 and two Y2 with respect to the total molecular weight of the compound R is 50% by mass or more, and 55% by mass or more is preferable in that the effect of the present invention is more excellent. The mass% or more is more preferable. The upper limit is not particularly limited, but is preferably 90% by mass or less from the viewpoint of ease of synthesis and response performance.
When the said ratio is less than 50 mass%, the fall of response performance will be caused.

The content of the specific compound in the electron blocking film is preferably 30% by mass or more and 100% by mass or less, and preferably 50% by mass or more and 100% by mass with respect to the total compound mass forming the electron blocking film from the viewpoint of response performance and heat resistance. % By mass or less is more preferable, 75% by mass or more and 100% by mass or less is more preferable, and 100% by mass is most preferable.
The total thickness of the electron blocking film is preferably 5 to 500 nm, more preferably 30 to 300 nm, and particularly preferably 50 to 200 nm from the viewpoint of dark current and response performance.

The electron blocking film may be composed of a plurality of layers.
An inorganic material can also be used as the electron blocking film. In general, since an inorganic material has a dielectric constant larger than that of an organic material, a large voltage is applied to the photoelectric conversion film when used as an electron blocking film, and the photoelectric conversion efficiency can be increased. Materials that can be used as electron blocking films include calcium oxide, chromium oxide, chromium copper oxide, manganese oxide, cobalt oxide, nickel oxide, copper oxide, gallium copper oxide, strontium copper oxide, niobium oxide, molybdenum oxide, indium copper oxide, and oxide. Examples include indium silver and iridium oxide.

  In addition, other electron donating organic materials other than the specific compound can be inserted as the electron blocking film, and further mixed with the specific compound and used as the electron blocking film.

The electron blocking film containing the specific compound also functions as a hole transport film.
A preferred embodiment of the photoelectric conversion element of the present invention is a photoelectric conversion element having a transparent conductive film, a photoelectric conversion film, an electron blocking film, and a conductive film in this order, wherein the electron blocking film is a specific compound. The aspect containing is mentioned.

Compounds A to C of the present invention can be produced by carrying out a partial modification according to a known method.
First, specific examples of the compound (A) are shown below, but the present invention is not limited thereto.

  Although the specific example of a compound (B) is shown below, this invention is not limited to these.

  Specific examples of the compound (C) are shown below, but the present invention is not limited to these.

[Photoelectric conversion film]
A photoelectric conversion film is a layer arrange | positioned between the transparent conductive film mentioned later and a conductive film with the electron blocking film mentioned above.
The organic material constituting the photoelectric conversion film preferably contains at least one of an organic p-type compound and an organic n-type compound.

<Organic p-type compound>
An organic p-type compound (p-type organic semiconductor) is a donor-type organic semiconductor, and is mainly represented by a hole-transporting organic compound and refers to an organic compound having a property of easily donating electrons. More specifically, an organic compound having a smaller ionization potential when two organic materials are used in contact with each other. Therefore, any organic compound can be used as the donor organic compound as long as it is an electron-donating organic compound. For example, triarylamine compound, benzidine compound, pyrazoline compound, styrylamine compound, hydrazone compound, triphenylmethane compound, carbazole compound, polysilane compound, thiophene compound, phthalocyanine compound, cyanine compound, merocyanine compound, oxonol compound, polyamine compound, indole Compounds, pyrrole compounds, pyrazole compounds, polyarylene compounds, condensed aromatic carbocyclic compounds (naphthalene derivatives, anthracene derivatives, phenanthrene derivatives, tetracene derivatives, pyrene derivatives, perylene derivatives, fluoranthene derivatives), nitrogen-containing heterocyclic compounds The metal complex etc. which it has as can be used. Not limited to this, as described above, any organic compound having an ionization potential smaller than that of the organic compound used as the n-type (acceptor property) compound may be used as the donor organic semiconductor.
Among the above, a triarylamine compound is preferable.

  Moreover, as an organic p-type compound, the compound represented by the following general formula (W) is preferable.

In formula (W), Z ₁ represents a ring containing at least two carbon atoms and a 5-membered ring, a 6-membered ring, or a condensed ring containing at least one of a 5-membered ring and a 6-membered ring. Z ₁ may have a substituent.
L ₁ , L ₂ and L ₃ each independently represents a methine group which may have a substituent.
n represents an integer of 0 or more.
Ar ₁₁ represents an arylene group or heteroarylene group which may have a substituent.
Ar ₁₁ and L ₁ may be bonded to each other to form a ring. The ring formed by combining Ar ₁₁ and L ₁ may have a substituent.
Ar ₁₂ and Ar ₁₃ each independently represents an aryl group or a heteroaryl group which may have a substituent. Ar ₁₁ and Ar ₁₂ , Ar ₁₁ and Ar ₁₃ , or Ar ₁₂ and Ar ₁₃ may be bonded to each other to form a ring.

In the above formula (W), Z ₁ represents a ring containing at least two carbon atoms and represents a 5-membered ring, a 6-membered ring, or a condensed ring containing at least one of a 5-membered ring and a 6-membered ring. .
As such a ring, what is normally used as an acidic nucleus with a merocyanine dye is preferable, and specific examples thereof include the following.

(A) 1,3-dicarbonyl nucleus: For example, 1,3-indandione nucleus, 1,3-cyclohexanedione, 5,5-dimethyl-1,3-cyclohexanedione, 1,3-dioxane-4,6 -Dione etc.
(B) pyrazolinone nucleus: for example, 1-phenyl-2-pyrazolin-5-one, 3-methyl-1-phenyl-2-pyrazolin-5-one, 1- (2-benzothiazolyl) -3-methyl-2- Pyrazolin-5-one and the like.
(C) Isoxazolinone nucleus: For example, 3-phenyl-2-isoxazolin-5-one, 3-methyl-2-isoxazolin-5-one and the like.
(D) Oxindole nucleus: For example, 1-alkyl-2,3-dihydro-2-oxindole and the like.
(E) 2,4,6-trioxohexahydropyrimidine nucleus: for example, barbituric acid or 2-thiobarbituric acid and its derivatives. Examples of the derivatives include 1-alkyl compounds such as 1-methyl and 1-ethyl, 1,3-dialkyl compounds such as 1,3-dimethyl, 1,3-diethyl and 1,3-dibutyl, 1,3-diaryls such as diphenyl, 1,3-di (p-chlorophenyl), 1,3-di (p-ethoxycarbonylphenyl), 1-alkyl-1-aryls such as 1-ethyl-3-phenyl And 1,3-diheteroaryls such as 1,3-di (2-pyridyl) and the like.
(F) 2-thio-2,4-thiazolidinedione nucleus: for example, rhodanine and derivatives thereof. Examples of the derivatives include 3-alkylrhodanine such as 3-methylrhodanine, 3-ethylrhodanine and 3-allylrhodanine, 3-arylrhodanine such as 3-phenylrhodanine, and 3- (2-pyridyl). And 3-heteroaryl rhodanine such as rhodanine.

(G) 2-thio-2,4-oxazolidinedione (2-thio-2,4- (3H, 5H) -oxazoledione nucleus: for example, 3-ethyl-2-thio-2,4-oxazolidinedione and the like.
(H) Tianaphthenone nucleus: For example, 3 (2H) -thianaphthenone-1,1-dioxide and the like.
(I) 2-thio-2,5-thiazolidinedione nucleus: For example, 3-ethyl-2-thio-2,5-thiazolidinedione and the like.
(J) 2,4-thiazolidinedione nucleus: For example, 2,4-thiazolidinedione, 3-ethyl-2,4-thiazolidinedione, 3-phenyl-2,4-thiazolidinedione and the like.
(K) Thiazolin-4-one nucleus: For example, 4-thiazolinone, 2-ethyl-4-thiazolinone and the like.
(L) 2,4-imidazolidinedione (hydantoin) nucleus: for example, 2,4-imidazolidinedione, 3-ethyl-2,4-imidazolidinedione, etc.
(M) 2-thio-2,4-imidazolidinedione (2-thiohydantoin) nucleus: for example, 2-thio-2,4-imidazolidinedione, 3-ethyl-2-thio-2,4-imidazolidine Zeon etc.
(N) Imidazolin-5-one nucleus: For example, 2-propylmercapto-2-imidazolin-5-one and the like.
(O) 3,5-pyrazolidinedione nucleus: for example, 1,2-diphenyl-3,5-pyrazolidinedione, 1,2-dimethyl-3,5-pyrazolidinedione and the like.
(P) Benzothiophene-3 (2H) -one nucleus: for example, benzothiophene-3 (2H) -one, oxobenzothiophene-3 (2H) -one, dioxobenzothiophene-3 (2H) -one and the like.
(Q) Indanone nucleus: For example, 1-indanone, 3-phenyl-1-indanone, 3-methyl-1-indanone, 3,3-diphenyl-1-indanone, 3,3-dimethyl-1-indanone and the like.
(R) Benzofuran-3- (2H) -one nucleus: for example, benzofuran-3- (2H) -one and the like.
(S) 2,2-dihydrophenalene-1,3-dione nucleus and the like.

Z ₁ is preferably a group represented by the following formula (Z1) from the viewpoint of more excellent responsiveness and sensitivity.

In formula (Z1), Z ₂ represents a ring containing at least 3 carbon atoms, and represents a 5-membered ring, a 6-membered ring, or a condensed ring containing at least one of a 5-membered ring and a 6-membered ring.
In formula (Z1), * represents a bonding position with L ₁ .

In the above formula (W), L ₁ , L ₂ and L ₃ each independently represent a methine group which may have a substituent. Examples of the substituent include a substituent W described later.
n represents an integer of 0 or more. Especially, it is preferable that it is 0-3, and it is more preferable that it is 0.

In the above formula (W), Ar ₁₁ represents an arylene group or heteroarylene group which may have a substituent. Examples of the substituent include a substituent W described later.
Ar ₁₁ is preferably an arylene group which may have a substituent.

When Ar ₁₁ is an arylene group, it is preferably an arylene group having 6 to 30 carbon atoms, and more preferably an arylene group having 6 to 20 carbon atoms. Specific examples of the ring constituting the arylene group include a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a fluorene ring, a triphenylene ring, a naphthacene ring, and a biphenyl ring. And a terphenyl ring (the three benzene rings may be connected in any connection manner).

When Ar ₁₁ is a heteroarylene group, it is preferably a heteroarylene group consisting of a 5-membered, 6-membered or 7-membered ring or a condensed ring thereof. Examples of the hetero atom contained in the heteroarylene group include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the ring constituting the heteroarylene group include a furan ring, a thiophene ring, a pyrrole ring, a pyrroline ring, a pyrrolidine ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, an imidazole ring, an imidazoline ring, and an imidazolidine. Ring, pyrazole ring, pyrazoline ring, pyrazolidine ring, triazole ring, furazane ring, tetrazole ring, pyran ring, thiine ring, pyridine ring, piperidine ring, oxazine ring, morpholine ring, thiazine ring, pyridazine ring, pyrimidine ring, pyrazine ring, Piperazine ring, triazine ring, benzofuran ring, isobenzofuran ring, benzothiophene ring, indole ring, indoline ring, isoindole ring, benzoxazole ring, benzothiazole ring, indazole ring, benzimidazole ring, quinoline ring, i Quinoline ring, cinnoline ring, phthalazine ring, quinazoline ring, quinoxaline ring, dibenzofuran ring, dibenzothiophene ring, carbazole ring, xanthene ring, acridine ring, phenanthridine ring, phenanthroline ring, phenazine ring, phenoxazine ring, thianthrene ring, India Examples include lysine ring, quinolidine ring, quinuclidine ring, naphthyridine ring, purine ring, and pteridine ring.

Ar ₁₁ and L ₁ may be bonded to each other to form a ring. Examples of the ring formed include a ring R described later. The ring formed by combining Ar ₁₁ and L ₁ may have a substituent. Examples of the substituent include a substituent W described later.

In the formula (W), Ar ₁₂ and Ar ₁₃ each independently represents an aryl group or a heteroaryl group which may have a substituent. Examples of the substituent include a substituent W described later.

When Ar ₁₂ or Ar ₁₃ is an aryl group, it is preferably an aryl group having 6 to 30 carbon atoms, and more preferably an aryl group having 6 to 20 carbon atoms. Specific examples of the ring constituting the aryl group are the same as the case where Ar ₁₁ described above is an arylene group.

When Ar ₁₂ or Ar ₁₃ is a heteroarylene group, a heteroarylene group consisting of a 5-membered, 6-membered or 7-membered ring or a condensed ring thereof is preferred. Specific examples of the hetero atom contained in the heteroarylene group are the same as those in the case where Ar ₁₁ described above is a heteroaryl group. Specific examples of the ring constituting the heteroarylene group are the same as the case where Ar ₁₁ described above is a heteroaryl group.

Ar ₁₁ and Ar ₁₂ , Ar ₁₁ and Ar ₁₃ , or Ar ₁₂ and Ar ₁₃ may be bonded to each other to form a ring. Examples of the ring formed include a ring R described later.

  As a suitable aspect of the compound represented by the said Formula (W), the compound represented by a following formula (W1) is mentioned, for example.

In the above formula (W1), the definition, specific examples and preferred embodiments of Z ₁ are the same as those in the above formula (W).

In the formula _{(W1), R} 41 ~R ₄₇ independently represent a hydrogen atom or a substituent. Examples of the substituent include a substituent W described later. R ₄₂ and R ₄₃ , R ₄₃ and R ₄₄ , R ₄₅ and R ₄₆ , and R ₄₁ and R ₄₆ may be bonded to each other to form a ring. Examples of the ring formed include a ring R described later.

  In the above formula (W1), m represents 0 or 1. Among these, 1 is preferable.

In the above formula (W1), the definitions, specific examples and preferred embodiments of Ar ₁₂ and Ar ₁₃ are the same as those in the above formula (W).
At least one of Ar ₁₂ and Ar ₁₃ is bonded to any one of R _{41 to} R ₄₆ via Xa which is a single bond or a divalent group to form a ring.
Here, Xa is an oxygen atom (—O—), a sulfur atom (—S—), an alkylene group, a silylene group (—SiR _a R _b —: R _a and R _b are each independently a hydrogen atom or A substituent (for example, a substituent W described later), —NR _a — (R _a represents a hydrogen atom or a substituent (for example, a substituent W described later)), an alkenylene group, a cycloalkylene group, a cyclo It represents an alkenylene group, an arylene group, a heteroarylene group, or a group obtained by combining these. Xa may have a substituent.

  As a most suitable aspect of the compound represented by the said compound (W), the compound represented by a following formula (W2) is mentioned, for example.

In the above formula (W2), Rz _{1 to} Rz ₄ each independently represents a hydrogen atom or a substituent. Examples of the substituent include a substituent W described later. Rz ₁ and Rz ₂ , Rz ₂ and Rz ₃ , Rz ₃ and Rz ₄ may be bonded to each other to form a ring. Examples of the ring formed include a ring R described later.

In the formula (W2), R ₄₁ , R ₄₂ , R ₄₃ , R ₄₅ and R ₄₆ each independently represent a hydrogen atom or a substituent. Examples of the substituent include a substituent W described later. R ₄₂ and R ₄₃ , R ₄₅ and R ₄₆ , R ₄₁ and R ₄₆ may be bonded to each other to form a ring. Examples of the ring formed include a ring R described later.

In the formula (W2), R _1a and R _1b each independently represent a hydrogen atom or a substituent. Examples of the substituent include a substituent W described later. Especially, it is preferable that it is an alkyl group (especially C1-C20), and it is more preferable that it is a C1-C3 alkyl group. R _1a and R _1b may combine with each other to form a ring. Examples of the ring formed include a ring R described later.

In the formula _{(W2), R} 51 ~R ₅₄ independently represent a hydrogen atom or a substituent. Examples of the substituent include a substituent W described later. R ₅₁ and R ₅₂ , R ₅₂ and R ₅₃ , R ₅₃ and R ₅₄ may be bonded to each other to form a ring. Examples of the ring formed include a ring R described later.

In the formula _{(W2), R} 55 ~R ₅₉ independently represents a hydrogen atom or a substituent. Examples of the substituent include a substituent W described later. R ₅₅ and R ₅₆ , R ₅₆ and R ₅₇ , R ₅₇ and R ₅₈ , and R ₅₈ and R ₅₉ may be bonded to each other to form a ring. Examples of the ring formed include a ring R described later.

(Substituent W)
It describes about the substituent W in this specification.
Examples of the substituent W include a halogen atom, an alkyl group (including a cycloalkyl group, a bicycloalkyl group, and a tricycloalkyl group), an alkenyl group (including a cycloalkenyl group and a bicycloalkenyl group), an alkynyl group, an aryl group, Heterocyclic group (may be referred to as heterocyclic group), cyano group, hydroxy group, nitro group, carboxy group, alkoxy group, aryloxy group, silyloxy group, heterocyclic oxy group, acyloxy group, carbamoyloxy group, alkoxycarbonyl Oxy group, aryloxycarbonyloxy group, amino group (including anilino group), ammonio group, acylamino group, aminocarbonylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfamoylamino group, alkyl or arylsulfo Ruamino group, mercapto group, alkylthio group, arylthio group, heterocyclic thio group, sulfamoyl group, sulfo group, alkyl or arylsulfinyl group, alkyl or arylsulfonyl group, acyl group, aryloxycarbonyl group, alkoxycarbonyl group, carbamoyl group, Aryl or heterocyclic azo group, imide group, phosphino group, phosphinyl group, phosphinyloxy group, phosphinylamino group, phosphono group, silyl group, hydrazino group, ureido group, boronic acid group (-B (OH) ₂ ), A phosphato group (—OPO (OH) ₂ ), a sulfato group (—OSO ₃ H), and other known substituents.
Details of the substituent are described in paragraph [0023] of JP-A-2007-234651.

(Ring R)
It describes about the ring R in this specification.
Examples of the ring R include an aromatic hydrocarbon ring, an aromatic heterocycle, a non-aromatic hydrocarbon ring, a non-aromatic heterocycle, or a polycyclic fused ring formed by combining these. More specifically, benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, fluorene ring, triphenylene ring, naphthacene ring, biphenyl ring, pyrrole ring, furan ring, thiophene ring, imidazole ring, oxazole ring, thiazole ring, pyridine ring , Pyrazine ring, pyrimidine ring, pyridazine ring, indolizine ring, indole ring, benzofuran ring, benzothiophene ring, isobenzofuran ring, quinolidine ring, quinoline ring, phthalazine ring, naphthyridine ring, quinoxaline ring, quinoxazoline ring, isoquinoline ring, carbazole Ring, phenanthridine ring, acridine ring, phenanthroline ring, thianthrene ring, chromene ring, xanthene ring, phenoxathiin ring, phenothiazine ring, phenazine ring, cyclopentane ring, cyclohexane ring, pyro Jin ring, piperidine ring, a tetrahydrofuran ring, tetrahydropyran ring, a tetrahydrothiophene ring, a tetrahydrothiopyran ring.
The ring R may have the substituent W.

  The compound represented by the general formula (W) can be produced by carrying out a partial modification according to a known method. Specific examples of the compound represented by the general formula (W) include the compounds described in JP2012-77064A and JP2013-214730A, and the compounds described below. It is not limited. Here, Me in the following specific examples represents methyl, and TMS represents trimethylsilyl.

<Organic n-type compound>
An organic n-type compound (n-type organic semiconductor) is an acceptor semiconductor, and is mainly represented by an electron-transporting compound and refers to a compound that easily accepts electrons. More specifically, it refers to a compound having a higher electron affinity when two compounds are used in contact with each other. Therefore, as the acceptor semiconductor, any compound can be used as long as it is an electron-accepting compound. Preferably, fullerenes selected from the group consisting of fullerenes and derivatives thereof, condensed aromatic carbocyclic compounds (naphthalene derivatives, anthracene derivatives, phenanthrene derivatives, tetracene derivatives, pyrene derivatives, perylene derivatives, fluoranthene derivatives), nitrogen atoms, oxygen Heterocyclic compounds containing atoms and sulfur atoms (for example, pyridine, pyrazine, pyrimidine, pyridazine, triazine, quinoline, quinoxaline, quinazoline, phthalazine, cinnoline, isoquinoline, pteridine, acridine, phenazine, phenanthroline, tetrazole, pyrazole, imidazole, thiazole , Oxazole, indazole, benzimidazole, benzotriazole, benzoxazole, benzothiazole, carbazole, purine, triazo Pyridazine, triazolopyrimidine, tetrazaindene, oxadiazole, imidazopyridine, pyralidine, pyrrolopyridine, thiadiazolopyridine, dibenzazepine, tribenzazepine, etc.), polyarylene compounds, fluorene compounds, cyclopentadiene compounds, silyl compounds, Examples thereof include a metal complex having a nitrogen heterocyclic compound as a ligand.

As said organic n-type compound, fullerene selected from the group which consists of fullerene and its derivative (s) is preferable. The fullerene, fullerene C _60, fullerene C _70, fullerene C _76, fullerene C _78, fullerene C _80, fullerene C _82, fullerene C _84, fullerene C _90, fullerene C _96, fullerene C _240, fullerene C _540, mixed Fullerene is represented, and the fullerene derivative represents a compound having a substituent added thereto. As the substituent, an alkyl group, an aryl group, or a heterocyclic group is preferable. As a fullerene derivative, the compound as described in Unexamined-Japanese-Patent No. 2007-123707 is preferable.

  The photoelectric conversion film preferably has a bulk heterostructure formed by mixing the above-described p-type compound (preferably a compound represented by the general formula (W)) and fullerenes. The bulk heterostructure is a film in which a p-type compound and an n-type compound are mixed and dispersed in a photoelectric conversion film, and can be formed by either a wet method or a dry method, but is preferably formed by a co-evaporation method. By including the heterojunction structure, it is possible to make up for the disadvantage that the carrier diffusion length of the photoelectric conversion film is short and to improve the photoelectric conversion efficiency of the photoelectric conversion film. The bulk heterojunction structure is described in detail in JP-A-2005-303266, [0013] to [0014].

  Content of fullerenes relative to the total content of p-type compounds and fullerenes (= film thickness in terms of single layer of fullerenes / (film thickness in terms of single layer of p-type compounds + single layer conversion of fullerenes) Is preferably 50% by volume or more, more preferably 55% by volume or more, and still more preferably 65% by volume or more. The upper limit is not particularly limited, but is preferably 95% by volume or less, and more preferably 90% by volume or less.

<Film formation method>
The photoelectric conversion film can be formed by a dry film formation method or a wet film formation method. Specific examples of the dry film forming method include a physical vapor deposition method such as a vacuum deposition method, a sputtering method, an ion plating method, and an MBE method, or a CVD method such as plasma polymerization. As the wet film forming method, an inkjet method, a spray method, a nozzle printing method, a spin coating method, a dip coating method, a casting method, a die coating method, a roll coating method, a bar coating method, a gravure coating method, etc. can be used. From the viewpoint of high-precision patterning, the inkjet method is preferable. A dry film forming method is preferable, and a vacuum evaporation method is more preferable. When forming a film by a vacuum evaporation method, manufacturing conditions such as the degree of vacuum and the evaporation temperature can be set according to a conventional method.

  The thickness of the photoelectric conversion film is not particularly limited, but is preferably 10 nm to 1000 nm, more preferably 50 nm to 800 nm, and particularly preferably 100 nm to 500 nm.

[electrode]
The electrodes (upper electrode (transparent conductive film) 15 and lower electrode (conductive film) 11) are made of a conductive material. As the conductive material, a metal, an alloy, a metal oxide, an electrically conductive compound, or a mixture thereof can be used.
Since light is incident from the upper electrode 15, it is preferable that the upper electrode 15 is sufficiently transparent to the light to be detected. Specifically, conductive metal oxides such as tin oxide (ATO, FTO) doped with antimony or fluorine, tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO), Metal thin films such as gold, silver, chromium, nickel, etc., and mixtures or laminates of these metals and conductive metal oxides, inorganic conductive materials such as copper iodide and copper sulfide, organics such as polyaniline, polythiophene, and polypyrrole Examples thereof include conductive materials and laminates of these with ITO. Among these, a transparent conductive metal oxide is preferable from the viewpoint of high conductivity and transparency.

  Usually, when the conductive film is made thinner than a certain range, a rapid increase in resistance value is caused. However, in the solid-state imaging device incorporating the photoelectric conversion element according to the present embodiment, the sheet resistance is preferably 100 to 10,000 Ω / □. Well, there is a large degree of freedom in the range of film thickness that can be made thin. Further, as the thickness of the upper electrode (transparent conductive film) 15 decreases, the amount of light absorbed decreases, and the light transmittance generally increases. An increase in light transmittance is very preferable because it increases the light absorption in the photoelectric conversion film 12 and increases the photoelectric conversion ability. Considering the suppression of leakage current, the increase in the resistance value of the thin film, and the increase in transmittance due to the thinning, the thickness of the upper electrode 15 is preferably 5 to 100 nm, more preferably 5 to 20 nm. It is desirable.

  Depending on the application, the lower electrode 11 may have transparency, or conversely, may use a material that does not have transparency and reflects light. Specifically, conductive metal oxides such as tin oxide doped with antimony or fluorine (ATO, FTO), tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO), Metals such as gold, silver, chromium, nickel, titanium, tungsten, and aluminum, and conductive compounds such as oxides and nitrides of these metals (for example, titanium nitride (TiN)), and these metals and conductivity Examples include mixtures or laminates with metal oxides, inorganic conductive materials such as copper iodide and copper sulfide, organic conductive materials such as polyaniline, polythiophene, and polypyrrole, and laminates of these with ITO or titanium nitride. .

The method for forming the electrode is not particularly limited, and can be appropriately selected depending on the electrode material. Specifically, it can be formed by a wet method such as a printing method or a coating method, a physical method such as a vacuum deposition method, a sputtering method, or an ion plating method, or a chemical method such as CVD or plasma CVD method.
When the material of the electrode is ITO, it can be formed by a method such as an electron beam method, a sputtering method, a resistance heating vapor deposition method, a chemical reaction method (such as a sol-gel method), or a dispersion of indium tin oxide. Furthermore, UV-ozone treatment, plasma treatment, or the like can be performed on a film formed using ITO. When the electrode material is TiN, various methods including a reactive sputtering method can be used, and further UV-ozone treatment, plasma treatment, and the like can be performed.

[Hole blocking film]
The photoelectric conversion element of the present invention may have a hole blocking (hole blocking) film.
An electron-accepting organic material can be used for the hole blocking film.
Examples of electron accepting materials include 1,3-bis (4-tert-butylphenyl-1,3,4-oxadiazolyl) phenylene (OXD-7) and other oxadiazole derivatives, anthraquinodimethane derivatives, and diphenylquinone derivatives. , Bathocuproine, bathophenanthroline, and derivatives thereof, triazole compounds, tris (8-hydroxyquinolinato) aluminum complexes, bis (4-methyl-8-quinolinato) aluminum complexes, distyrylarylene derivatives, silole compounds, etc. Can do. Moreover, even if it is not an electron-accepting organic material, it can be used if it is a material which has sufficient electron transport property. A porphyrin compound, a styryl compound such as DCM (4-dicyanomethylene-2-methyl-6- (4- (dimethylaminostyryl))-4H pyran), or a 4H pyran compound can be used. Specifically, compounds described in JP-A-2008-72090, [0073] to [0078] are preferable.

The thickness of each hole blocking film is preferably 10 to 200 nm, more preferably 30 to 150 nm, and particularly preferably 50 to 100 nm. This is because if the thickness is too thin, the dark current suppressing effect is lowered, and if it is too thick, the photoelectric conversion efficiency is lowered.
The manufacturing method of the hole blocking film is the same as the electron blocking film described above.

[substrate]
The photoelectric conversion element may further include a substrate. The type of the substrate used is not particularly limited, and a semiconductor substrate, a glass substrate, or a plastic substrate can be used.
The position of the substrate is not particularly limited, but usually a conductive film, a photoelectric conversion film, and a transparent conductive film are laminated on the substrate in this order.

[Sealing layer]
The photoelectric conversion element may further include a sealing layer. The performance of photoelectric conversion materials may deteriorate significantly due to the presence of degradation factors such as water molecules. Ceramics such as dense metal oxides, metal nitrides, and metal nitride oxides that do not penetrate water molecules and diamond-like materials Covering and sealing the entire photoelectric conversion film with a sealing layer such as carbon (DLC) can prevent the deterioration.
In addition, as a sealing layer, you may select and manufacture a material according to description of Paragraph [0210]-[0215] of Unexamined-Japanese-Patent No. 2011-082508.

[Optical sensor]
Examples of the use of the photoelectric conversion element include a photovoltaic cell and an optical sensor, but the photoelectric conversion element of the present invention is preferably used as an optical sensor. As an optical sensor, the photoelectric conversion element used alone may be used, or a line sensor in which the photoelectric conversion elements are linearly arranged or a two-dimensional sensor arranged on a plane is preferable. The photoelectric conversion element of the present invention converts optical image information into an electrical signal using an optical system and a drive unit like a scanner in a line sensor, and optically converts optical image information like an imaging module in a two-dimensional sensor. The system functions as an image sensor by forming an image on a sensor and converting it into an electrical signal.
Since the photovoltaic cell is a power generation device, the efficiency of converting light energy into electrical energy is an important performance, but dark current, which is a current in a dark place, is not a functional problem. Further, a subsequent heating step such as installation of a color filter is not necessary. Since it is important to convert light and dark signals into electrical signals with high accuracy, the efficiency of converting light intensity into current is also important for optical sensors. Low dark current is required.

[Image sensor]
Next, a configuration example of an image sensor including the photoelectric conversion element 10a will be described.
In the configuration examples described below, members having the same configuration / action as those already described are denoted by the same or corresponding reference numerals in the drawings, and the description is simplified or omitted.
An image sensor is an element that converts optical information of an image into an electric signal. A plurality of photoelectric conversion elements are arranged on a matrix in the same plane, and an optical signal is converted into an electric signal in each photoelectric conversion element (pixel). That can be output to the outside of the imaging device for each pixel sequentially. Therefore, each pixel is composed of one photoelectric conversion element and one or more transistors.
FIG. 2 is a schematic cross-sectional view showing a schematic configuration of an image sensor for explaining an embodiment of the present invention. This imaging device is used by being mounted on an imaging device such as a digital camera or a digital video camera, an imaging module such as an electronic endoscope or a mobile phone, or the like.
This imaging element has a plurality of photoelectric conversion elements having the configuration shown in FIG. 1 and a circuit board on which a readout circuit for reading a signal corresponding to the charge generated in the photoelectric conversion film of each photoelectric conversion element is formed. A plurality of photoelectric conversion elements are arranged one-dimensionally or two-dimensionally on the same surface above the circuit board.

  2 includes a substrate 101, an insulating layer 102, a connection electrode 103, a pixel electrode (lower electrode) 104, a connection portion 105, a connection portion 106, the photoelectric conversion film, and the electron blocking. A photoelectric conversion layer 107 made of a film, a counter electrode (upper electrode) 108, a buffer layer 109, a sealing layer 110, a color filter (CF) 111, a partition 112, a light shielding layer 113, and a protective layer 114 A counter electrode voltage supply unit 115 and a readout circuit 116.

  The pixel electrode 104 has the same function as the lower electrode 11 of the photoelectric conversion element 10a shown in FIG. The counter electrode 108 has the same function as the upper electrode 15 of the photoelectric conversion element 10a shown in FIG. The photoelectric conversion layer 107 has the same configuration as the layer provided between the lower electrode 11 and the upper electrode 15 of the photoelectric conversion element 10a illustrated in FIG.

  The substrate 101 is a glass substrate or a semiconductor substrate such as Si. An insulating layer 102 is formed on the substrate 101. A plurality of pixel electrodes 104 and a plurality of connection electrodes 103 are formed on the surface of the insulating layer 102.

  The photoelectric conversion layer 107 is a layer common to all the photoelectric conversion elements provided on the plurality of pixel electrodes 104 so as to cover them.

  The counter electrode 108 is one electrode provided on the photoelectric conversion layer 107 and common to all the photoelectric conversion elements. The counter electrode 108 is formed up to the connection electrode 103 arranged outside the photoelectric conversion layer 107 and is electrically connected to the connection electrode 103.

  The connection part 106 is embedded in the insulating layer 102 and is a plug or the like for electrically connecting the connection electrode 103 and the counter electrode voltage supply part 115. The counter electrode voltage supply unit 115 is formed on the substrate 101 and applies a predetermined voltage to the counter electrode 108 via the connection unit 106 and the connection electrode 103. When the voltage to be applied to the counter electrode 108 is higher than the power supply voltage of the image sensor, the power supply voltage is boosted by a booster circuit such as a charge pump to supply the predetermined voltage.

  The readout circuit 116 is provided on the substrate 101 corresponding to each of the plurality of pixel electrodes 104, and reads out a signal corresponding to the charge collected by the corresponding pixel electrode 104. The readout circuit 116 is configured by, for example, a CCD, a CMOS circuit, a TFT circuit, or the like, and is shielded from light by a light shielding layer (not shown) disposed in the insulating layer 102. The readout circuit 116 is electrically connected to the corresponding pixel electrode 104 via the connection unit 105.

  The buffer layer 109 is formed on the counter electrode 108 so as to cover the counter electrode 108. The sealing layer 110 is formed on the buffer layer 109 so as to cover the buffer layer 109. The color filter 111 is formed at a position facing each pixel electrode 104 on the sealing layer 110. The partition wall 112 is provided between the color filters 111 and is for improving the light transmission efficiency of the color filter 111.

  The light blocking layer 113 is formed in a region other than the region where the color filter 111 and the partition 112 are provided on the sealing layer 110, and prevents light from entering the photoelectric conversion layer 107 formed outside the effective pixel region. The protective layer 114 is formed on the color filter 111, the partition 112, and the light shielding layer 113, and protects the entire image sensor 100.

  In the imaging device 100 configured as described above, when light is incident, the light is incident on the photoelectric conversion layer 107, and charges are generated here. Holes in the generated charges are collected by the pixel electrode 104, and a voltage signal corresponding to the amount is output to the outside of the image sensor 100 by the readout circuit 116.

The manufacturing method of the image sensor 100 is as follows.
On the circuit board on which the common electrode voltage supply unit 115 and the readout circuit 116 are formed, the connection units 105 and 106, the plurality of connection electrodes 103, the plurality of pixel electrodes 104, and the insulating layer 102 are formed. The plurality of pixel electrodes 104 are arranged on the surface of the insulating layer 102 in a square lattice pattern, for example.

  Next, the photoelectric conversion layer 107 is formed on the plurality of pixel electrodes 104 by, for example, a vacuum heating deposition method. Next, the counter electrode 108 is formed on the photoelectric conversion layer 107 under vacuum by, for example, sputtering. Next, the buffer layer 109 and the sealing layer 110 are sequentially formed on the counter electrode 108 by, for example, a vacuum heating deposition method. Next, after forming the color filter 111, the partition 112, and the light shielding layer 113, the protective layer 114 is formed, and the imaging element 100 is completed.

  Even in the method for manufacturing the image sensor 100, a plurality of steps can be taken even if a step of placing the image sensor 100 being manufactured under non-vacuum is added between the process of forming the photoelectric conversion layer 107 and the process of forming the sealing layer 110. The performance deterioration of the photoelectric conversion element can be prevented. By adding this step, it is possible to suppress the manufacturing cost while preventing the performance degradation of the image sensor 100.

  Examples are shown below, but the present invention is not limited thereto.

<Example A>
<Example 1>
<Production of photoelectric conversion element>
A photoelectric conversion element having the configuration shown in FIG. Here, the photoelectric conversion element includes the lower electrode 11, the electron blocking film 16 </ b> A, the photoelectric conversion film 12, and the upper electrode 15.
Specifically, an amorphous ITO film is formed on a glass substrate by a sputtering method to form a lower electrode 11 (thickness: 30 nm), and a compound (1) described later is vacuum-heat deposited on the lower electrode 11. An electron blocking film 16A (thickness: 200 nm) was formed by the method. Here, the vapor deposition was performed by putting the compound (1) in a crucible and heating it under vacuum (a vacuum degree of 4 × 10 ⁻⁴ Pa or less). Moreover, it vapor-deposited so that the vapor deposition rate of a compound (1) might be set to 3.0 Å (angstrom) / second (3.0 * 10 < ^-10 > m / second).
Further, with the substrate temperature controlled at 25 ° C., the following photoelectric conversion material Dye (1) and fullerene (C ₆₀ ) are vacuumed on the electron blocking film 16A so as to be 100 nm and 300 nm, respectively, in terms of a single layer. A photoelectric conversion film 12 was formed by co-evaporation by heating vapor deposition.
Further, an amorphous ITO film was formed on the photoelectric conversion film 12 by sputtering to form an upper electrode 15 (transparent conductive film) (thickness: 10 nm). An SiO film was formed as a sealing layer on the upper electrode 15 by heat evaporation, and then an aluminum oxide (Al ₂ O ₃ ) layer was formed thereon by ALCVD to produce a photoelectric conversion element (1st element).

Next, the crucible used when the 1st element was produced (the one containing the remaining compound (1)) was used as it was, and the deposition rate was 3.0 Å / second (3.0 × 10 ⁻¹⁰ m / second). The deposition was carried out for 5 hours. After newly replacing the glass substrate, a photoelectric conversion element (2nd element) was produced according to the same procedure as the 1st element, except that the vapor deposition was performed using the compound (1) remaining in the crucible.

<Examples 2-18, Comparative Examples 1-20>
A photoelectric conversion element (1st) was prepared in the same manner as in Example 1 except that compounds (2) to (18) and comparative compounds RC (1) to (20) described later were used instead of the compound (1). Element and 2nd element).
Hereinafter, compounds (1) to (18) are shown.

  Hereinafter, comparative compounds RC (1) to (20) are shown.

In addition, the said compounds (1)-(18) and comparative compound RD (1) -RD (20) were synthesize | combined using a well-known method. The compound was identified by MS measurement and ¹ H-NMR measurement.

<Confirmation of element drive>
About the obtained photoelectric conversion element (1st element, 2nd element), it was confirmed whether it functions as a photoelectric conversion element. Specifically, a voltage is applied to the lower electrode and the upper electrode of the obtained photoelectric conversion element so that the electric field strength is 2.0 × 10 ⁵ V / cm, and the current values in the dark place and the bright place are obtained. It was measured. As a result, each photoelectric conversion element showed a dark current of 100 nA / cm ² or less in the dark place, but showed a current of 10 μA / cm ² or more in the bright place, and it was confirmed that it functions as a photoelectric conversion element.

<Dark current evaluation>
About the obtained photoelectric conversion element (1st element, 2nd element), the element produced as an annealing process was left for 30 minutes on a 200 degreeC hotplate, and after cooling to room temperature, the dark current was measured. As a result, when the dark current of the photoelectric conversion element of Example 1 is 1, the relative value is 5 or less is “A”, the relative value is greater than 5 and 20 or less is “B”, and the relative value is greater than 20 is “C”. " The results are shown in Table 1. Practically, “A” or “B” is preferable, and “A” is preferable.
The relative value is calculated from the following formula.
(Relative value) = (dark current value in each photoelectric conversion element / dark current value in the photoelectric conversion element of Example 1)
Further, in order to verify the heat resistance of each element, the prepared element was left on a hot plate at 220 ° C. for 30 minutes, cooled to room temperature, and then dark current was measured in the same manner as described above. In Table 1, “A” indicates that the relative value with respect to the dark current value of each element before heating is 3 or less, “B” indicates that it is greater than 3 and 5 or less, and “C” indicates that it is greater than 5. Practically, “A” or “B” is preferable, and “A” is preferable.

<Response evaluation>
About the obtained photoelectric conversion element (1st element, 2nd element), the element produced as annealing treatment was left to stand on a 200 degreeC hotplate for 30 minutes, and after cooling to room temperature, the responsiveness was evaluated. Measure the photocurrent when applying an electric field of 1.0 × 10 ⁵ V / cm to the annealed photoelectric conversion element (1st element, 2nd element) and irradiating light from the upper electrode (transparent conductive film) side Then, the rise time from 0 to 98% signal intensity was obtained. As a result, when the rise time of the photoelectric conversion element a of Example 1 is 1, the relative value is 1.2 or less “A”, the relative value greater than 1.2 and 1.5 or less “B”, A value larger than 1.5 was designated as “C”. The results are shown in Table 2. Practically, it is preferably “A” or “B”, and more preferably “A”.
The relative value is calculated from the following formula.
(Relative value) = (rise time from 0 to 98% signal intensity in each photoelectric conversion element / rise time from 0 to 98% signal intensity in the photoelectric conversion element a of Example 1)
Furthermore, in order to verify the heat resistance of each device, the fabricated device was left on a hot plate at 220 ° C. for 30 minutes, cooled to room temperature, and then responsiveness was measured in the same manner as described above. Table 1 shows that the relative value of the rise time from 0 to 98% signal intensity of each element before heating is 2 or less “A”, 2 to 5 and less than “B” and 5 or more. “C”. Practically, “A” or “B” is preferable, and “A” is preferable.

In Table 1, the “total molecular weight” column intends the total molecular weight of the electron blocking material used in each example and comparative example, and is a value obtained by rounding off the first decimal place.
The “partial molecular weight” column intends the molecular weight of Z when the electron blocking material is Compound A, the total molecular weight of two Y when Compound B is used, and the total molecular weight of Ya, Yb and Yc when Compound C is used. The value rounded to the first place.
The “partial molecular weight / total molecular weight × 100 (%)” column shows the value of the above (partial molecular weight / total molecular weight) × 100, and is a value obtained by rounding off the first decimal place.

As shown in Table 1 above, it was confirmed that the photoelectric conversion element of the present invention exhibited excellent low dark current property, high-speed response, heat resistance, and manufacturing suitability.
In particular, it was confirmed that when the compounds (1), (5), (6), (8), and (10) were used (corresponding to the above compound R), more excellent effects were obtained.

  On the other hand, when RD-1 used in the Example column of Patent Document 1 is used (corresponding to Comparative Example 1) and when other compounds are used (Comparative Examples 2 to 20), the desired effect is obtained. It was not obtained.

<Example B>
The photoelectric conversion element was produced similarly to the said Example 1 except having changed the photoelectric conversion material Dye (1) of Example 1 into the following photoelectric conversion material Dye (2).

For other electron blocking materials other than the compound (1), photoelectric conversion elements were produced according to the same procedure as in Example A, and the same evaluation was performed. The same results as in Table 1 were obtained. Furthermore, the efficiency (external quantum efficiency) was evaluated. A voltage was applied to the obtained photoelectric conversion element so that the electric field strength was 2.0 × 10 ⁵ V / cm, and the sensitivity at the wavelength where the extinction coefficient was the largest in the wavelength region of 500 nm or more at this voltage was measured. did. As a result, in all the corresponding elements, the efficiency improvement of about 1.1 to 1.2 times can be confirmed when the photoelectric conversion material Dye (2) is used rather than the photoelectric conversion material Dye (1). It was.

<Production of image sensor>
An image sensor similar to that shown in FIG. 2 was produced. That is, after depositing amorphous TiN 30 nm on the CMOS substrate by sputtering, patterning is performed by photolithography so that one pixel exists on each photodiode (PD) on the CMOS substrate to form the lower electrode. After the film formation of the electron blocking material, it was prepared in the same manner as each example and each comparative example. The evaluation was performed in the same manner, and the same results as in Table 1 were obtained. It was found that the imaging element is suitable for manufacturing and exhibits excellent performance.

10a, 10b Photoelectric conversion element 11 Lower electrode (conductive film)
12 Photoelectric conversion film 15 Upper electrode (transparent conductive film)
16A Electron blocking film 16B Hole blocking film 100 Image sensor 101 Substrate 102 Insulating layer 103 Connection electrode 104 Pixel electrode (lower electrode)
105 connecting portion 106 connecting portion 107 photoelectric conversion layer 108 counter electrode (upper electrode)
109 Buffer layer 110 Sealing layer 111 Color filter (CF)
112 partition wall 113 light shielding layer 114 protective layer 115 counter electrode voltage supply unit 116 readout circuit

Claims (13)

A photoelectric conversion element having a conductive film, a transparent conductive film, and a photoelectric conversion film and an electron blocking film disposed between the conductive film and the transparent conductive film,
The electron blocking film is represented by the formula (A), the compound A having a molecular weight of 550 to 900, the compound B represented by the formula (B), the compound B having a molecular weight of 650 to 950, and the formula (C). And a photoelectric conversion element comprising at least one compound selected from the group consisting of compound C having a molecular weight of 800 to 950.
Formula (A) Z- (R) _n
(Z represents a condensed polycyclic aromatic heterocyclic group containing the partial structure represented by formula (1). R represents a non-aromatic group. N represents 0 or an integer of 1 or more. The ratio of the molecular weight of Z to the total molecular weight of Compound A is 50% by mass or more.
In the formula (1), X ₁ represents N (X ₃ ). X ₃ represents a bond. X ₂ each independently represents a nitrogen atom or C (X ₄ ), and X ₄ represents a bond or a hydrogen atom. )

Formula (B) (R) _n -YY- (R) _n
(Y each independently represents a condensed polycyclic aromatic hydrocarbon group or a condensed polycyclic aromatic heterocyclic group, and at least one of Y is a condensed polycyclic aromatic containing a partial structure represented by the formula (1) R represents a non-aromatic group, each independently represents an integer of 0 or an integer greater than or equal to 1. The total molecular weight of two Ys relative to the total molecular weight of compound B Is at least 50% by mass.)

(Ya, Yb and Yc each independently represent a condensed polycyclic aromatic hydrocarbon group or a condensed polycyclic aromatic heterocyclic group, and at least one of Ya, Yb and Yc is represented by the formula (1). And R each independently represents a non-aromatic group, each n independently represents an integer of 0 or 1 or more. (The ratio of the total molecular weight of Ya, Yb and Yc to the molecular weight is 50% by mass or more.) The photoelectric conversion element according to claim 1, wherein the partial structure represented by the formula (1) is a partial structure represented by the formula (2).

(In formula (2), X ₁ represents N (X ₃ ). X ₃ represents a bond. X ₄ each independently represents a bond or a hydrogen atom.) The at least one compound is the compound C;
In formula (C), Ya is a condensed polycyclic aromatic hydrocarbon group, and Yb and Yc are each independently a condensed polycyclic aromatic heterocyclic group containing a partial structure represented by the above formula (1). The photoelectric conversion element according to claim 1. The photoelectric conversion element according to claim 1, wherein the at least one compound is a compound R represented by the formula (R) and having a molecular weight of 800 to 950.

(In Formula (R), Y1 is represented by the group represented by Formula (K1), the group represented by Formula (K2), the group represented by Formula (K3), and the formula (K4). Y2 represents the same group selected from the group consisting of groups, the group represented by the formula (L1), the group represented by the formula (L2), and the formula (L3). R represents any one selected from the group consisting of the groups represented by R. Each R independently represents a non-aromatic group, each n independently represents 0 or an integer of 1 or more. The ratio of the total molecular weight of Y1 and two Y2 to the total molecular weight is 50% by mass or more.)


(In formulas (K1) and (K2), R ₁₀₁ independently represents C (R ₁₀₂ ) (R ₁₀₃ ), an oxygen atom, a sulfur atom, or N (R ₁₀₄ ). R ₁₀₂ and R ₁₀₃ Each independently represents a hydrogen atom or a bond, R ₁₀₄ represents a bond, and in formulas (K1) to (K4), * represents a bonding position with Y2. R _{102 to} R ₁₀₄ When any of these is a bond, the bond is bonded to R.
In formula (L1), R _{61 to} R ₆₈ each independently represent a hydrogen atom or a bond. When any of R _{61 to} R ₆₈ is a bond, the bond is bonded to R. * Indicates a binding position with Y1.
In formula (L2), R _{71 to} R ₇₆ each independently represent a hydrogen atom or a bond. R ₁₀₅ represents a single bond. a represents 3 or 4, b represents 2 or 3, and a + b = 6. A plurality of R ₇₁ and R ₇₆ may be the same or different. * Indicates a binding position with Y1. Note _that either one _{R 72} of _{R 71,} directly, _{or, C (R 102) (R} 103), an oxygen atom, a sulfur atom, or via a linking group represented by _{N (R 104)} They may combine to form a ring. R ₁₀₂ and R ₁₀₃ each independently represent a hydrogen atom or a bond. R ₁₀₄ represents a bond. When any of R _{71 to} R ₇₆ and R _{102 to} R ₁₀₄ is a bond, the bond is bonded to R. In formula (L2), ** is bonded to the benzene ring to which R ₇₁ is bonded when a is 3, and is bonded to the benzene ring to which R ₇₆ is bonded when a is 4.
In formula (L3), R _{81 to} R ₉₂ each independently represent a hydrogen atom or a bond. R ₁₀₁ independently represents C (R ₁₀₂ ) (R ₁₀₃ ), an oxygen atom, a sulfur atom, or N (R ₁₀₄ ). R ₁₀₂ and R ₁₀₃ each independently represent a hydrogen atom or a bond. R ₁₀₄ represents a bond. * Indicates a binding position with Y1. When any of R _{81 to} R ₉₂ and R _{102 to} R ₁₀₄ is a bond, the bond is bonded to R. ) The photoelectric conversion element of any one of Claims 1-4 in which the said photoelectric conversion film contains the compound represented by Formula (W).

(In the formula (W), Z ₁ represents a ring containing at least two carbon atoms and represents a 5-membered ring, a 6-membered ring, or a condensed ring containing at least one of a 5-membered ring and a 6-membered ring. Z ₁ may have a substituent.
L ₁ , L ₂ and L ₃ each independently represents a methine group which may have a substituent.
n represents an integer of 0 or more.
Ar ₁₁ represents an arylene group or heteroarylene group which may have a substituent.
Ar ₁₁ and L ₁ may be bonded to each other to form a ring. The ring formed by combining Ar ₁₁ and L ₁ may have a substituent.
Ar ₁₂ and Ar ₁₃ each independently represents an aryl group or a heteroaryl group which may have a substituent. Ar ₁₁ and Ar ₁₂ , Ar ₁₁ and Ar ₁₃ , or Ar ₁₂ and Ar ₁₃ may be bonded to each other to form a ring. ) The photoelectric conversion element according to claim 5, wherein the compound represented by the formula (W) is a compound represented by the formula (W1).

(In Formula (W1), Z ₁ represents a ring containing at least two carbon atoms and represents a 5-membered ring, a 6-membered ring, or a condensed ring containing at least one of a 5-membered ring and a 6-membered ring. Z ₁ may have a substituent.
R _{41 to} R ₄₇ each independently represent a hydrogen atom or a substituent. R ₄₂ and R ₄₃ , R ₄₃ and R ₄₄ , R ₄₅ and R ₄₆ , and R ₄₁ and R ₄₆ may be bonded to each other to form a ring.
m represents 0 or 1.
Ar ₁₂ and Ar ₁₃ each independently represents an aryl group or a heteroaryl group which may have a substituent. Ar ₁₂ and Ar ₁₃ may be bonded to each other to form a ring.
At least one of Ar ₁₂ and Ar ₁₃ is bonded to any one of R _{41 to} R ₄₆ via Xa which is a single bond or a divalent group to form a ring. Xa represents an oxygen atom, a sulfur atom, an alkylene group, a silylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, a heteroarylene group, —NR _a — (R _a represents a hydrogen atom or a substituent. ) Or a combination of these. Xa may have a substituent. ) The photoelectric conversion element according to claim 5 or 6, wherein the compound represented by the formula (W) is a compound represented by the formula (W2).

(In formula (W2), Rz _{1 to} Rz ₄ each independently represents a hydrogen atom or a substituent. Rz ₁ and Rz ₂ , Rz ₂ and Rz ₃ , Rz ₃ and Rz ₄ are bonded to each other. A ring may be formed.
R ₄₁ , R ₄₂ , R ₄₃ , R ₄₅ and R ₄₆ each independently represents a hydrogen atom or a substituent. R ₄₂ and R ₄₃ , R ₄₅ and R ₄₆ , and R ₄₁ and R ₄₆ may be bonded to each other to form a ring.
R _1a and R _1b each independently represent a hydrogen atom or a substituent. R _1a and R _1b may be bonded to each other to form a ring.
R _{51 to} R ₅₄ each independently represents a hydrogen atom or a substituent. R ₅₁ and R ₅₂ , R ₅₂ and R ₅₃ , and R ₅₃ and R ₅₄ may be bonded to each other to form a ring.
R ₅₅ to R ₅₉ each independently represent a hydrogen atom or a substituent. R ₅₅ and R ₅₆ , R ₅₆ and R ₅₇ , R ₅₇ and R ₅₈ , and R ₅₈ and R ₅₉ may be bonded to each other to form a ring. )   The photoelectric conversion element according to claim 1, wherein the photoelectric conversion film further contains an organic n-type compound.   The photoelectric conversion element according to claim 8, wherein the organic n-type compound contains fullerenes selected from the group consisting of fullerenes and derivatives thereof.   The photoelectric conversion element of any one of Claims 1-9 in which light injects into the said photoelectric converting film through the said transparent conductive film.   The photoelectric conversion element according to claim 1, wherein the transparent conductive film is made of a transparent conductive metal oxide.   The optical sensor which consists of a photoelectric conversion element of any one of Claims 1-11.   The image pick-up element containing the photoelectric conversion element of any one of Claims 1-11.