CN117769897A - Compound, composition, and photoelectric conversion element - Google Patents

Abstract

The subject of the present invention is to reduce dark current. The solution is a composition containing a p-type semiconductor material and an n-type semiconductor material, wherein the n-type semiconductor material contains a compound represented by the following formula (I). D ¹ -B ¹ -A ¹ (I) (In formula (I), D ¹ represents an electron-donating group, A ¹ represents an electron-withdrawing group, and B ¹ represents one or more structural units and constitutes a π total The divalent group of the yoke system.) The band gap of the n-type semiconductor material is preferably larger than the band gap of the p-type semiconductor material.

Description

Compound, composition and photoelectric conversion element

Technical Field

The present invention relates to a compound as a semiconductor material, a composition containing the compound, and a photoelectric conversion element using the composition as a material.

Background Art

Photoelectric conversion elements are extremely useful devices from the viewpoints of, for example, energy saving and reduction of carbon dioxide emissions, and have attracted attention.

A photoelectric conversion element refers to an element having at least a pair of electrodes consisting of an anode and a cathode, and an active layer disposed between the pair of electrodes. In a photoelectric conversion element, at least one of the pair of electrodes is made of a transparent or translucent material, and light is incident on the active layer from the side of the transparent or translucent electrode. By the energy (hν) of the light incident on the active layer, charges (holes and electrons) are generated in the active layer, and the generated holes move toward the anode and the electrons move toward the cathode. Then, the charges reaching the anode and the cathode are taken out to the outside of the element.

In photoelectric conversion elements, further improvement of the photoelectric conversion efficiency is required, and therefore, various semiconductor materials have been developed and reported (see Non-Patent Document 1).

Prior art literature

Non-patent literature

Non-patent document 1: Joule 3, 1140-1151, April 17, 2019

Summary of the invention

Problems to be solved by the invention

However, it is reported that the n-type semiconductor material reported in the above-mentioned Non-Patent Document 1 can indeed achieve a photoelectric conversion efficiency of about 15%.

However, it is still difficult to say that the reduction of dark current required for a photoelectric conversion element as a light detection element is sufficient.

Therefore, there is a need for a further semiconductor material that can satisfy the characteristics required of a photoelectric conversion element, in particular, can reduce dark current in a photodetection element.

Means for solving problems

The present inventors have conducted intensive studies to solve the above problems and, as a result, have found that the above problems can be solved by a compound having a predetermined structure and a composition containing the compound described below, thereby completing the present invention.

Therefore, the present invention provides the following [1] to [13].

[1] A composition comprising a p-type semiconductor material and an n-type semiconductor material,

The n-type semiconductor material includes a compound represented by the following formula (I).

D ¹ -B ¹ -A ¹ (I)

(In formula (I),

^D1 represents an electron-donating group,

^A1 represents an electron-withdrawing group,

^B1 represents a divalent group containing one or more structural units and constituting a π-conjugated system.

[2] The composition according to [1], wherein the band gap of the n-type semiconductor material is larger than the band gap of the p-type semiconductor material.

[3] The composition according to [1] or [2], wherein the energy level of the LUMO of ^D1 ( _ED-LUMO ), the energy level of the LUMO of at least one of the one or more structural units constituting ^B1 (Eπ _-LUMO ), and the energy level of the LUMO of ^A1 ( _EA-LUMO ) satisfy the conditions represented by the following formula.

E _D-LUMO ＞E _B-LUMO ＞E _A-LUMO

[4] The composition according to any one of [1] to [3], wherein the p-type semiconductor material is a polymer compound.

[5] The composition according to [4], wherein the p-type semiconductor material is a polymer compound having an absorption peak wavelength greater than 700 nm.

[6] An ink composition comprising the composition according to any one of [1] to [5] and a solvent.

[7] A film having a bulk heterojunction structure, comprising the composition described in any one of [1] to [5].

[8] A photoelectric conversion element comprising the film described in [7] as an active layer.

[9] The photoelectric conversion element according to claim 8, which is a light detection element.

[10] A compound represented by the following formula (I).

D ¹ -B ¹ -A ¹ (I)

(In formula (I),

^D1 represents an electron-donating group,

^A1 is an electron withdrawing group, which means an electron withdrawing group having a ring structure,

^B1 represents a divalent group containing one or more structural units and constituting a π-conjugated system,

At least one of the first structural units among the one or more structural units is a structural unit represented by the following formula (II), and the remaining second structural units other than the first structural unit are divalent groups containing unsaturated bonds, divalent aromatic carbocyclic groups, or divalent aromatic heterocyclic groups.

When there are two or more first structural units, the two or more first structural units may be the same or different from each other. When there are two or more second structural units, the two or more second structural units may be the same or different from each other.

[Chemical formula 1]

(In formula (II),

^Ar1 and ^Ar2 each independently represent an aromatic carbon ring which may have a substituent or an aromatic hetero ring which may have a substituent,

Y represents a direct bond, a group represented by -C(=O)-, or an oxygen atom,

R independently represents:

Hydrogen atoms,

Halogen atoms,

An alkyl group which may have a substituent,

a cycloalkyl group which may have a substituent, an aryl group which may have a substituent, an alkoxy group which may have a substituent, a cycloalkyloxy group which may have a substituent, an aryloxy group which may have a substituent, an alkylthio group which may have a substituent, a cycloalkylthio group which may have a substituent, an arylthio group which may have a substituent, a monovalent heterocyclic group which may have a substituent, a substituted amino group which may have a substituent, an acyl group which may have a substituent, an imine residue which may have a substituent, an amide group which may have a substituent, an imido group which may have a substituent, a substituted oxycarbonyl group which may have a substituent, an alkenyl group which may have a substituent, a cycloalkenyl group which may have a substituent, an alkynyl group which may have a substituent, a cycloalkynyl group which may have a substituent, a cyano group,

Nitro,

a group represented by -C(=O)-R ^a , or a group represented by -SO ₂ -R ^b ,

^Ra and ^Rb each independently represent:

Hydrogen atoms,

An alkyl group which may have a substituent, an aryl group which may have a substituent, an alkoxy group which may have a substituent, an aryloxy group which may have a substituent, or a monovalent heterocyclic group which may have a substituent.

The multiple Rs present may be the same or different from each other.)

[11] The compound according to [10], wherein the first structural unit is a structural unit represented by the following formula (III).

[Chemical formula 2]

(In formula (III),

Y and R are as defined above,

^X1 and ^X2 each independently represent a sulfur atom or an oxygen atom,

^Z1 and ^Z2 each independently represent a group represented by =C(R)- or a nitrogen atom.)

[12] The compound according to [11], wherein the first structural unit is a structural unit represented by the following formula (IV-1).

[Chemical formula 3]

(In formula (IV-1),

Y represents a group represented by -C(=O)- or an oxygen atom,

R independently represents:

Hydrogen atoms,

Halogen atoms,

An alkyl group which may have a substituent,

A cycloalkyl group which may have a substituent,

an aryl group which may have a substituent,

An alkoxy group which may have a substituent,

A cycloalkoxy group which may have a substituent,

an aryloxy group which may have a substituent,

an alkylthio group which may have a substituent,

a cycloalkylthio group which may have a substituent,

an arylthio group which may have a substituent,

a monovalent heterocyclic group which may have a substituent,

A substituted amino group which may have a substituent,

an acyl group which may have a substituent,

an imine residue which may have a substituent,

an amide group which may have a substituent,

an imide group which may have a substituent,

an optionally substituted oxycarbonyl group,

an alkenyl group which may have a substituent,

A cycloalkenyl group which may have a substituent,

an alkynyl group which may have a substituent,

a cycloalkynyl group which may have a substituent,

Cyano,

Nitro,

-C(=O)-R ^a group, or

-SO ₂ -R ^b represented by the group,

^Ra and ^Rb each independently represent:

Hydrogen atoms,

An alkyl group which may have a substituent,

an aryl group which may have a substituent,

An alkoxy group which may have a substituent,

An aryloxy group which may have a substituent, or

A monovalent heterocyclic group which may have a substituent.

The multiple Rs present may be the same or different from each other.)

[13] The compound according to any one of [10] to [12], wherein ^B1 is a divalent group having any one structure selected from the group consisting of the structures represented by the following formulae (VI-1) to (VI-16).

-CU1-(VI-1)

-CU1-CU1-(VI-2)

-CU1-CU2-(VI-3)

-CU1-CU1-CU1-(VI-4)

-CU1-CU2-CU1-(VI-5)

-CU1-CU1-CU2-(VI-6)

-CU1-CU2-CU2-(VI-7)

-CU2-CU1-CU2-(VI-8)

-CU1-CU1-CU1-CU1-(VI-9)

-CU1-CU1-CU1-CU2-(VI-10)

-CU1-CU1-CU2-CU1-(VI-11)

-CU1-CU1-CU2-CU2-(VI-12)

-CU1-CU2-CU1-CU2-(VI-13)

-CU1-CU2-CU2-CU1-(VI-14)

-CU1-CU2-CU2-CU2-(VI-15)

-CU2-CU1-CU2-CU2-(VI-16)

(In formula (V-1) to formula (V-16),

CU1 represents the first structural unit mentioned above,

CU2 represents the above-mentioned second structural unit.

When there are more than two CU1s, the two or more CU1s may be the same or different from each other, and when there are more than two CU2s, the two or more CU2s may be the same or different from each other. In formula (VI-8), the case where the two CU2s are the same is not included.)

Effects of the Invention

According to the present invention, it is possible to provide a compound that is particularly effective in reducing dark current, a composition containing the compound, and a photoelectric conversion element using the composition as a material for a functional layer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram schematically showing a configuration example of a photoelectric conversion element.

FIG. 2 is a diagram schematically showing a configuration example of an image detection unit.

FIG. 3 is a diagram schematically showing a configuration example of a fingerprint detection unit.

FIG. 4 is a diagram schematically showing a configuration example of an image detection unit for an X-ray imaging device.

FIG. 5 is a diagram schematically showing a configuration example of a vein detection unit used in a vein recognition device.

FIG. 6 is a diagram schematically showing a configuration example of an image detection unit for an indirect TOF type distance measuring device.

DETAILED DESCRIPTION

Hereinafter, the compound of the embodiment of the present invention is described, and the photoelectric conversion element using the compound of the present embodiment is described further with reference to the accompanying drawings. It should be noted that the accompanying drawings only schematically illustrate the shape, size and configuration of the constituent elements to the extent that the invention can be understood. The present invention is not limited to the following description, and each constituent element can be appropriately changed within the scope of the present invention. In addition, the composition of the embodiment of the present invention is not necessarily limited to manufacturing or using the configuration shown in the accompanying drawings.

First, the terms commonly used in the following description are explained.

The "non-fullerene compound" refers to a compound that is neither fullerene nor a fullerene derivative.

The "π-conjugated system" refers to a system in which π electrons are delocalized in multiple bonds.

The "polymer compound" refers to a polymer having a molecular weight distribution and a polystyrene-equivalent number average molecular weight of 1×10 ³ or more and 1×10 ⁸ or less. The total amount of structural units contained in the polymer compound is 100 mol%.

The "structural unit" means that one or more residues derived from a raw material compound (monomer) exist in the compound and polymer compound of the present embodiment.

A "hydrogen atom" may be a protium atom or a deuterium atom.

Examples of the "halogen atom" include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

The embodiment of “optionally having a substituent” includes two embodiments: the case where all hydrogen atoms constituting the compound or group are unsubstituted, and the case where part or all of one or more hydrogen atoms are substituted with a substituent.

Examples of the "substituent" include a halogen atom, an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, an alkynyl group, a cycloalkynyl group, an alkoxy group, a cycloalkyloxy group, an alkylthio group, a cycloalkylthio group, an aryl group, an aryloxy group, an arylthio group, a monovalent heterocyclic group, a substituted amino group, an acyl group, an imide residue, an amide group, an imido group, a substituted oxycarbonyl group, a cyano group, an alkylsulfonyl group, and a nitro group. It should be noted that when the number of carbon atoms is referred to in this specification, the number of carbon atoms does not include the number of carbon atoms of the substituent.

In this specification, unless otherwise specified, "alkyl" may be any of linear, branched, and cyclic. The number of carbon atoms in a linear alkyl group does not include the number of carbon atoms in the substituent, and is usually 1 to 50, preferably 1 to 30, and more preferably 1 to 20. The number of carbon atoms in a branched or cyclic alkyl group does not include the number of carbon atoms in the substituent, and is usually 3 to 50, preferably 3 to 30, and more preferably 4 to 20.

Specific examples of the alkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, 2-ethylbutyl, n-hexyl, cyclohexyl, n-heptyl, cyclohexylmethyl, cyclohexylethyl, n-octyl, 2-ethylhexyl, 3-n-propylheptyl, adamantyl, n-decyl, 3,7-dimethyloctyl, 2-ethyloctyl, 2-n-hexyl-decyl, n-dodecyl, tetradecyl, hexadecyl, octadecyl and eicosyl.

The alkyl group may have a substituent. The alkyl group having a substituent is, for example, a group in which a hydrogen atom in the alkyl group exemplified above is substituted with a substituent such as an alkoxy group, an aryl group, or a fluorine atom.

Specific examples of the alkyl group having a substituent include a trifluoromethyl group, a pentafluoroethyl group, a perfluorobutyl group, a perfluorohexyl group, a perfluorooctyl group, a 3-phenylpropyl group, a 3-(4-methylphenyl)propyl group, a 3-(3,5-dihexylphenyl)propyl group, and a 6-ethoxyhexyl group.

The "cycloalkyl group" may be a monocyclic group or a polycyclic group. The cycloalkyl group may have a substituent. The number of carbon atoms in the cycloalkyl group does not include the number of carbon atoms in the substituent, and is usually 3 to 30, preferably 12 to 19.

Examples of the cycloalkyl group include unsubstituted alkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl and adamantyl, and groups in which hydrogen atoms in these groups are substituted with substituents such as alkyl groups, alkoxy groups, aryl groups and fluorine atoms.

Specific examples of the cycloalkyl group having a substituent include a methylcyclohexyl group and an ethylcyclohexyl group.

The "p-valent aromatic carbocyclic group" refers to an atomic group remaining after removing p hydrogen atoms directly bonded to carbon atoms constituting the ring from an aromatic hydrocarbon which may have a substituent. The p-valent aromatic carbocyclic group may further have a substituent.

The "aryl group" is a monovalent aromatic carbocyclic group, and refers to an atomic group remaining after removing one hydrogen atom directly bonded to a carbon atom constituting the ring from an aromatic hydrocarbon which may have a substituent.

The aryl group may have a substituent. Specific examples of the aryl group include phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-pyrenyl, 2-pyrenyl, 4-pyrenyl, 2-fluorenyl, 3-fluorenyl, 4-fluorenyl, 2-phenylphenyl, 3-phenylphenyl, 4-phenylphenyl, and groups in which hydrogen atoms in these groups are substituted with substituents such as alkyl, alkoxy, aryl, and fluorine atoms.

The "alkoxy group" may be any of linear, branched, and cyclic. The number of carbon atoms in a linear alkoxy group does not include the number of carbon atoms in the substituent, and is usually 1 to 40, preferably 1 to 10. The number of carbon atoms in a branched or cyclic alkoxy group does not include the number of carbon atoms in the substituent, and is usually 3 to 40, preferably 4 to 10.

The alkoxy group may have a substituent. Specific examples of the alkoxy group include a methoxy group, an ethoxy group, a n-propoxy group, an isopropoxy group, a n-butoxy group, an isobutoxy group, a tert-butoxy group, a n-pentyloxy group, a n-hexyloxy group, a cyclohexyloxy group, a n-heptyloxy group, a n-octyloxy group, a 2-ethylhexyloxy group, a n-nonyloxy group, a n-decyloxy group, a 3,7-dimethyloctyloxy group, a 3-heptyldodecyloxy group, a lauryloxy group, and groups in which hydrogen atoms in these groups are substituted with alkoxy groups, aryl groups, or fluorine atoms.

The cycloalkyl group of the "cycloalkoxy group" may be a monocyclic group or a polycyclic group. The cycloalkoxy group may have a substituent. The number of carbon atoms in the cycloalkoxy group is usually 3 to 30, preferably 12 to 19, excluding the number of carbon atoms in the substituent.

Examples of the cycloalkoxy group include unsubstituted cycloalkoxy groups such as cyclopentyloxy groups, cyclohexyloxy groups, and cycloheptyloxy groups, and groups in which hydrogen atoms in these groups are substituted with fluorine atoms or alkyl groups.

The number of carbon atoms in the "aryloxy group" is usually 6 to 60, preferably 6 to 48, not including the number of carbon atoms in the substituent.

The aryloxy group may have a substituent. Specific examples of the aryloxy group include phenoxy, 1-naphthyloxy, 2-naphthyloxy, 1-anthryloxy, 9-anthryloxy, 1-pyreneoxy, and groups in which hydrogen atoms in these groups are substituted with substituents such as alkyl groups, alkoxy groups, and fluorine atoms.

The "alkylthio group" may be any of linear, branched, and cyclic. The number of carbon atoms in a linear alkylthio group does not include the number of carbon atoms in the substituent, and is usually 1 to 40, preferably 1 to 10. The number of carbon atoms in a branched or cyclic alkylthio group does not include the number of carbon atoms in the substituent, and is usually 3 to 40, preferably 4 to 10.

The alkylthio group may have a substituent. Specific examples of the alkylthio group include methylthio, ethylthio, propylthio, isopropylthio, butylthio, isobutylthio, tert-butylthio, pentylthio, hexylthio, cyclohexylthio, heptylthio, octylthio, 2-ethylhexylthio, nonylthio, decylthio, 3,7-dimethyloctylthio, laurylthio and trifluoromethylthio.

The cycloalkyl group of the "cycloalkylthio group" may be a monocyclic group or a polycyclic group. The cycloalkylthio group may have a substituent. The number of carbon atoms in the cycloalkylthio group is usually 3 to 30, preferably 12 to 19, excluding the number of carbon atoms in the substituent.

As an example of the cycloalkylthio group which may have a substituent, a cyclohexylthio group can be mentioned.

The number of carbon atoms in the "arylthio group" is usually 6 to 60, preferably 6 to 48, not including the number of carbon atoms in the substituent.

The arylthio group may have a substituent. Examples of the arylthio group include a phenylthio group, a C1-C12 alkoxyphenylthio group (C1-C12 means that the carbon number of the group immediately following it is 1-12. The same applies hereinafter), a C1-C12 alkylphenylthio group, a 1-naphthylthio group, a 2-naphthylthio group, and a pentafluorophenylthio group.

The “p-valent heterocyclic group” (p represents an integer of 1 or greater) refers to an atomic group remaining after removing p hydrogen atoms directly bonded to a carbon atom or a heteroatom constituting the ring from a heterocyclic compound which may have a substituent.

The p-valent heterocyclic group may further have a substituent. The p-valent heterocyclic group generally has 2 to 30 carbon atoms, preferably 2 to 6 carbon atoms, excluding the carbon atoms of the substituent.

Examples of substituents that the heterocyclic compound may have include halogen atoms, alkyl groups, aryl groups, alkoxy groups, aryloxy groups, alkylthio groups, arylthio groups, monovalent heterocyclic groups, substituted amino groups, acyl groups, imide residues, amide groups, imide groups, substituted oxycarbonyl groups, alkenyl groups, alkynyl groups, cyano groups, and nitro groups. The p-valent heterocyclic group includes a "p-valent aromatic heterocyclic group".

The "p-valent aromatic heterocyclic group" refers to an atomic group remaining after removing p hydrogen atoms directly bonded to carbon atoms or heteroatoms constituting the ring from an aromatic heterocyclic compound which may have a substituent. The p-valent aromatic heterocyclic group may further have a substituent.

The aromatic heterocyclic compound includes compounds in which the heterocycle itself exhibits aromaticity and compounds in which the heterocycle itself does not exhibit aromaticity but an aromatic ring is fused to the heterocycle.

Specific examples of the aromatic heterocyclic compounds in which the heterocyclic ring itself exhibits aromaticity include oxadiazole, thiadiazole, thiazole, oxazole, thiophene, pyrrole, phosphole, furan, pyridine, pyrazine, pyrimidine, triazine, pyridazine, quinoline, isoquinoline, carbazole and dibenzophosphole.

Among the aromatic heterocyclic compounds, specific examples of compounds in which the aromatic heterocyclic ring itself does not exhibit aromaticity but an aromatic ring is condensed on the heterocyclic ring include phenoxazine, phenothiazine, dibenzoborole, dibenzosilole and benzopyran.

The number of carbon atoms in the monovalent heterocyclic group is usually 2 to 60, preferably 4 to 20, not including the number of carbon atoms in the substituent.

The monovalent heterocyclic group may have a substituent. Specific examples of the monovalent heterocyclic group include a thienyl group, a pyrrolyl group, a furyl group, a pyridyl group, a piperidyl group, a quinolyl group, an isoquinolyl group, a pyrimidyl group, a triazine group, and groups in which hydrogen atoms in these groups are substituted with an alkyl group, an alkoxy group, or the like.

"Substituted amino group" refers to an amino group having a substituent. Examples of the substituent of the amino group include an alkyl group, an aryl group, and a monovalent heterocyclic group, and an alkyl group, an aryl group, or a monovalent heterocyclic group is preferred. The substituted amino group usually has 2 to 30 carbon atoms.

Examples of the substituted amino group include dialkylamino groups such as dimethylamino and diethylamino; and diarylamino groups such as diphenylamino, bis(4-methylphenyl)amino, bis(4-tert-butylphenyl)amino and bis(3,5-di-tert-butylphenyl)amino.

The "acyl group" may have a substituent. The number of carbon atoms of the acyl group does not include the number of carbon atoms of the substituent, and is usually 2 to 20, preferably 2 to 18. Specific examples of the acyl group include acetyl, propionyl, butyryl, isobutyryl, pivaloyl, benzoyl, trifluoroacetyl and pentafluorobenzoyl.

"Imine residue" refers to the atomic group remaining after removing one hydrogen atom directly bonded to a carbon atom or a nitrogen atom constituting a carbon-nitrogen double bond from an imine compound. "Imine compound" refers to an organic compound having a carbon-nitrogen double bond in the molecule. Examples of imine compounds include aldimine, ketimines, and compounds in which the hydrogen atom bonded to the nitrogen atom constituting a carbon-nitrogen double bond in aldimine is substituted with an alkyl group or the like.

The imine residue generally has 2 to 20 carbon atoms, and preferably has 2 to 18 carbon atoms. Examples of the imine residue include groups represented by the following structural formulas.

[Chemical formula 4]

"Acylamide" refers to the atomic group remaining after removing one hydrogen atom bonded to a nitrogen atom from an amide. The number of carbon atoms in an amide is usually 1 to 20, preferably 1 to 18. Specific examples of amide include formamide, acetamide, propionamide, butyramide, benzamide, trifluoroacetamide, pentafluorobenzamide, diformamide, diacetamide, dipropionamide, dibutyramide, dibenzamide, di-trifluoroacetamide and di-pentafluorobenzamide.

The "acylimido group" refers to an atomic group remaining after removing one hydrogen atom bonded to a nitrogen atom from an imide. The number of carbon atoms in the acylimido group is usually 4 to 20. Specific examples of the acylimido group include groups represented by the following structural formulas.

[Chemical formula 5]

The "substituted oxycarbonyl group" refers to a group represented by R'-O-(C=O)-, wherein R' represents an alkyl group, an aryl group, an aralkyl group or a monovalent heterocyclic group.

The number of carbon atoms of the substituted oxycarbonyl group is usually 2 to 60, preferably 2 to 48, not including the number of carbon atoms of the substituent.

Specific examples of the substituted oxycarbonyl group include methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, isobutoxycarbonyl, tert-butoxycarbonyl, pentyloxycarbonyl, hexyloxycarbonyl, cyclohexyloxycarbonyl, heptyloxycarbonyl, octyloxycarbonyl, 2-ethylhexyloxycarbonyl, nonyloxycarbonyl, decyloxycarbonyl, 3,7-dimethyloctyloxycarbonyl, dodecyloxycarbonyl, trifluoromethoxycarbonyl, pentafluoroethoxycarbonyl, perfluorobutoxycarbonyl, perfluorohexyloxycarbonyl, perfluorooctyloxycarbonyl, phenoxycarbonyl, naphthoxycarbonyl and pyridyloxycarbonyl.

The "alkenyl group" may be any of a linear, branched, or cyclic group. The number of carbon atoms in a linear alkenyl group does not include the number of carbon atoms in the substituent, and is usually 2 to 30, preferably 3 to 20. The number of carbon atoms in a branched or cyclic alkenyl group does not include the number of carbon atoms in the substituent, and is usually 3 to 30, preferably 4 to 20.

The alkenyl group may have a substituent. Specific examples of the alkenyl group include vinyl, 1-propenyl, 2-propenyl, 2-butenyl, 3-butenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 5-hexenyl, 7-octenyl, and groups in which hydrogen atoms in these groups are substituted by alkyl groups, alkoxy groups, aryl groups, or fluorine atoms.

The "cycloalkenyl group" may be a monocyclic group or a polycyclic group. The cycloalkenyl group may have a substituent. The number of carbon atoms in the cycloalkenyl group is usually 3 to 30, preferably 12 to 19, excluding the number of carbon atoms in the substituent.

Examples of the cycloalkenyl group include unsubstituted cycloalkenyl groups such as cyclohexenyl group and groups in which hydrogen atoms in these groups are substituted with alkyl groups, alkoxy groups, aryl groups or fluorine atoms.

Examples of the cycloalkenyl group having a substituent include a methylcyclohexenyl group and an ethylcyclohexenyl group.

The "alkynyl group" may be any of a linear, branched, and cyclic group. The number of carbon atoms in a linear alkenyl group does not include the number of carbon atoms in the substituent, and is usually 2 to 20, preferably 3 to 20. The number of carbon atoms in a branched or cyclic alkenyl group does not include the number of carbon atoms in the substituent, and is usually 4 to 30, preferably 4 to 20.

The alkynyl group may have a substituent. Specific examples of the alkynyl group include ethynyl, 1-propynyl, 2-propynyl, 2-butynyl, 3-butynyl, 3-pentynyl, 4-pentynyl, 1-hexynyl, 5-hexynyl, and groups in which hydrogen atoms in these groups are substituted with alkoxy groups, aryl groups, or fluorine atoms.

The "cycloalkynyl group" may be a monocyclic group or a polycyclic group. The cycloalkynyl group may have a substituent. The number of carbon atoms in the cycloalkynyl group is usually 4 to 30, preferably 12 to 19, excluding the number of carbon atoms in the substituent.

Examples of the cycloalkynyl group include cycloalkynyl groups having no substituent such as cyclohexynyl group, and groups in which hydrogen atoms in these groups are substituted with an alkyl group, an alkoxy group, an aryl group or a fluorine atom.

Examples of the cycloalkynyl group having a substituent include a methylcyclohexynyl group and an ethylcyclohexynyl group.

The "alkylsulfonyl group" may be linear or branched. The alkylsulfonyl group may have a substituent. The number of carbon atoms in the alkylsulfonyl group does not include the number of carbon atoms in the substituent, and is usually 1 to 30. Specific examples of the alkylsulfonyl group include a methylsulfonyl group, an ethylsulfonyl group, and a dodecylsulfonyl group.

The symbol "*" that may be added to a chemical formula represents a bonding bond.

"Ink composition" refers to a liquid used in a coating method, and is not limited to a colored liquid. In addition, "coating method" includes a method of forming a film (layer) using a liquid substance, for example, a slit die coating method, a slit coating method, a doctor blade coating method, a spin coating method, a casting method, a micro-gravure coating method, a gravure coating method, a rod coating method, a roller coating method, a wire rod coating method, a dip coating method, a spray coating method, a screen printing method, a gravure printing method, a flexographic printing method, an offset printing method, an inkjet coating method, a dispenser printing method, a nozzle coating method, and a capillary coating method.

The ink composition may be a solution, or may be a dispersion such as a dispersion, an emulsion (emulsion), or a suspension (suspension).

The “absorption peak wavelength” is a parameter determined based on an absorption peak of an absorption spectrum measured within a predetermined wavelength range, and refers to the wavelength of an absorption peak having the highest absorbance among the absorption peaks of the absorption spectrum.

The composition according to the embodiment of the present invention is a composition containing a p-type semiconductor material and an n-type semiconductor material, and the n-type semiconductor material contains a compound represented by the following formula (I).

D ¹ -B ¹ -A ¹ (I)

In formula (I),

^D1 represents an electron-donating group,

^A1 represents an electron-withdrawing group,

^B1 represents a divalent group including one or more structural units and constituting a π-conjugated system.

The following is a specific description.

1. Compounds (n-type semiconductor materials)

First, the "compound" of this embodiment will be described. The compound of this embodiment is generally an n-type semiconductor material, and can be suitably used as a semiconductor material of a photoelectric conversion element, especially an active layer.

It should be noted that in the active layer, whether the compound of the present embodiment functions as a p-type semiconductor material or an n-type semiconductor material can be relatively determined based on the energy level value of the HOMO (Highest Occupied Molecular Orbital: the highest occupied molecular orbital) or the energy level value of the LUMO (Lowest Unoccupied Molecular Orbital: the lowest unoccupied molecular orbital) of the selected compound. The compound of the present embodiment can be particularly suitable for use as an n-type semiconductor material in the active layer of a photoelectric conversion element.

The relationship between the HOMO and LUMO energy level values of the p-type semiconductor material contained in the active layer and the HOMO and LUMO energy level values of the n-type semiconductor material can be appropriately set within the range in which the photoelectric conversion element (photodetection element) operates.

The “compound” in this embodiment is a compound represented by the following formula (I).

D ¹ -B ¹ -A ¹ (I)

In formula (I),

^D1 represents an electron-donating group,

^A1 represents an electron-withdrawing group,

^B1 represents a divalent group including one or more structural units and constituting a π-conjugated system.

The compound of this embodiment is a non-fullerene compound represented by the above formula (I), and is a compound in which ^A1 as an electron-withdrawing monovalent group is bonded to one end of ^B1 , and ^D1 as an electron-donating monovalent group is bonded to the other end, and ^B1 is a divalent group containing one or more structural units and constituting a π conjugated system. In the compound of this embodiment, it is preferred that the compound including ^D1 and ^A1 as a whole constitutes a π conjugated system.

Hereinafter, A ¹ , B ¹ and D ¹ which can constitute the compound represented by formula (I) will be specifically described.

(1) About ^A1

^A1 is an electron-withdrawing monovalent group.

Specifically, ^A1 is a monovalent group having a function of further reducing the electron density of ^B1 which is a divalent group constituting the π-conjugated system.

^A1 is preferably an electron withdrawing group having a ring structure.

In the present embodiment, examples of ^A1 as an electron-withdrawing monovalent group include a group represented by -CH=C(-CN) ₂ and groups represented by the following formulae (a-1) to (a-10).

[Chemical formula 6]

In formula (a-1) to formula (a-8),

T represents a carbocyclic ring which may have a substituent or a heterocyclic ring which may have a substituent. The carbocyclic ring and the heterocyclic ring may be a monocyclic ring or a condensed ring. When these rings have multiple substituents, the multiple substituents present may be the same or different from each other.

As examples of the carbocyclic ring which may have a substituent as represented by T, aliphatic carbocyclic rings and aromatic carbocyclic rings may be cited, preferably aromatic carbocyclic rings. As specific examples of the carbocyclic ring which may have a substituent as represented by T, a benzene ring, a naphthalene ring, an anthracene ring, a tetracene ring, a pentacene ring, a pyrene ring and a phenanthrene ring may be cited, preferably a benzene ring, a naphthalene ring and a phenanthrene ring, more preferably a benzene ring and a naphthalene ring, and further preferably a benzene ring. These rings may have a substituent.

Examples of the heterocyclic ring which may have a substituent represented by T include aliphatic heterocyclic rings and aromatic heterocyclic rings, preferably aromatic carbocyclic rings. Specific examples of the heterocyclic ring which may have a substituent represented by T include pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, pyrrole ring, furan ring, thiophene ring, imidazole ring, oxazole ring, thiazole ring and thienothiophene ring, preferably thiophene ring and pyridine ring, pyrazine ring, thiazole ring and thienothiophene ring, more preferably thiophene ring. These rings may have a substituent.

Examples of the substituent that the carbocyclic or heterocyclic ring represented by T may have include a halogen atom, an alkyl group, an alkoxy group, an aryl group, a cyano group, and a monovalent heterocyclic group, preferably a fluorine atom, a chlorine atom, an alkoxy group having 1 to 6 carbon atoms, and/or an alkyl group having 1 to 6 carbon atoms.

X ⁴ , X ⁵ and X ⁶ each independently represent an oxygen atom, a sulfur atom, an alkylidene group or a group represented by ═C(—CN) ₂ , preferably an oxygen atom, a sulfur atom or a group represented by ═C(—CN) ₂ .

^X7 represents a hydrogen atom or a halogen atom, a cyano group, an alkyl group which may have a substituent, an alkoxy group which may have a substituent, an aryl group which may have a substituent, or a monovalent heterocyclic group. ^X7 is preferably a cyano group.

^Ra1 , ^Ra2 , ^Ra3 , ^Ra4 , ^Ra5 and ^Ra6 each independently represent a hydrogen atom, an alkyl group which may have a substituent, a halogen atom, an alkoxy group which may have a substituent, an aryl group which may have a substituent, or a monovalent heterocyclic group, preferably an alkyl group which may have a substituent or an aryl group which may have a substituent.

[Chemical formula 7]

In formula (a-9) and formula (a-10),

^Ra7 and ^Ra8 each independently represent a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an alkoxy group which may have a substituent, a cycloalkyloxy group which may have a substituent, a monovalent aromatic carbocyclic group which may have a substituent, or a monovalent aromatic heterocyclic group which may have a substituent, and the multiple ^Ra7 and ^Ra8 present may be the same as or different from each other.

Specific examples of the electron withdrawing group represented by ^A1 include groups represented by the following formulae (a-1-1) to (a-1-4), (a-5-1), (a-6-1), (a-6-2), and (a-7-1).

[Chemical formula 8]

In formula (a-1-1) to formula (a-1-4), formula (a-5-1), formula (a-6-1) and formula (a-7-1),

The multiple R ^a11s present each independently represent a hydrogen atom or a substituent,

^Ra1 , ^Ra2 , ^Ra3 , ^Ra4 and ^Ra5 each independently have the same meaning as above.

^Ra11 is preferably a hydrogen atom, a halogen atom, an alkoxy group, a cyano group or an alkyl group. ^Ra1 , ^Ra2 , ^Ra3 , ^Ra4 and ^Ra5 are preferably an alkyl group which may have a substituent or an aryl group which may have a substituent.

Preferred examples of the electron withdrawing group represented by ^A1 include groups represented by the following formulas.

[Chemical formula 9]

[Chemical formula 10]

(2) About ^B1

^B1 is a divalent group including one or more structural units and constituting a π-conjugated system. Specifically, ^B1 is a divalent group including one or more atoms π-bonded to each other and having a π electron cloud extending over the entire ^B1 .

The one or more structural units contained in ^B1 preferably include a structural unit represented by the following formula (III).

[Chemical formula 11]

In formula (III),

^Ar1 and ^Ar2 each independently represent an aromatic carbon ring which may have a substituent or an aromatic hetero ring which may have a substituent,

Y represents a direct bond, a group represented by -C(=O)-, or an oxygen atom,

R independently represents:

Hydrogen atoms,

Halogen atoms,

An alkyl group which may have a substituent,

A cycloalkyl group which may have a substituent,

an aryl group which may have a substituent,

An alkoxy group which may have a substituent,

A cycloalkoxy group which may have a substituent,

an aryloxy group which may have a substituent,

an alkylthio group which may have a substituent,

a cycloalkylthio group which may have a substituent,

an arylthio group which may have a substituent,

a monovalent heterocyclic group which may have a substituent,

A substituted amino group which may have a substituent,

an acyl group which may have a substituent,

an imine residue which may have a substituent,

an amide group which may have a substituent,

an imide group which may have a substituent,

an optionally substituted oxycarbonyl group,

an alkenyl group which may have a substituent,

A cycloalkenyl group which may have a substituent,

an alkynyl group which may have a substituent,

a cycloalkynyl group which may have a substituent,

Cyano,

Nitro,

-C(=O)-R ^a group, or

-SO ₂ -R ^b represented by the group,

^Ra and ^Rb each independently represent:

Hydrogen atoms,

An alkyl group which may have a substituent,

an aryl group which may have a substituent,

An alkoxy group which may have a substituent,

An aryloxy group which may have a substituent, or

A monovalent heterocyclic group which may have a substituent.

The multiple Rs that exist may be the same as or different from each other.

In formula (III), the aromatic carbon ring that can constitute Ar ¹ and Ar ² is preferably a benzene ring and a naphthalene ring, more preferably a benzene ring and a naphthalene ring, and further preferably a benzene ring. These rings may have a substituent.

The aromatic heterocyclic ring that can constitute Ar ¹ and Ar ² is preferably an oxadiazole ring, a thiadiazole ring, a thiazole ring, an oxazole ring, a thiophene ring, a thienothiophene ring, a benzothiophene ring, a pyrrole ring, a phosphole ring, a furan ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, a triazine ring, a pyridazine ring, a quinoline ring, an isoquinoline ring, a carbazole ring and a dibenzophosphole ring, and a phenoxazine ring, a phenothiazine ring, a dibenzoborole ring, a dibenzosilole ring and a benzopyran ring. These rings may have a substituent.

The halogen atom represented by R is preferably a fluorine atom.

The alkyl group which may have a substituent and is represented by R is preferably an alkyl group which may have a carbon number of 1 to 20 which may have a substituent, more preferably an alkyl group which may have a carbon number of 1 to 15 which may have a substituent, further preferably an alkyl group which may have a carbon number of 1 to 12 which may have a substituent, and still further preferably an alkyl group which may have a carbon number of 1 to 10 which may have a substituent.

The substituent that the alkyl group represented by R may have is preferably a halogen atom, more preferably a fluorine atom and/or a chlorine atom.

The cycloalkyl group which may have a substituent and is represented by R is preferably a cycloalkyl group having 3 to 10 carbon atoms which may have a substituent, more preferably a cycloalkyl group having 5 to 6 carbon atoms which may have a substituent, and still more preferably a cyclohexyl group which may have a substituent.

The aryl group which may have a substituent and is represented by R is preferably an aryl group having 6 to 15 carbon atoms which may have a substituent, and more preferably a phenyl group or a naphthyl group which may have a substituent.

The substituent that the aryl group represented by R may have is preferably a halogen atom (e.g., a chlorine atom, a fluorine atom), an alkyl group having 1 to 12 carbon atoms (e.g., a methyl group, a trifluoromethyl group, a tert-butyl group, an octyl group, a dodecyl group), an alkoxy group having 1 to 12 carbon atoms (e.g., a methoxy group, an ethoxy group, an octyloxy group), an alkylsulfonyl group having 1 to 12 carbon atoms (e.g., a dodecylsulfonyl group) and/or a cyano group.

The alkoxy group which may have a substituent and is represented by R is preferably an alkoxy group having 1 to 10 carbon atoms which may have a substituent, more preferably an alkoxy group having 1 to 8 carbon atoms which may have a substituent, and further preferably a methoxy group, an ethoxy group, a propoxy group, a 3-methylbutoxy group or a 2-ethylhexyloxy group, and these groups may have a substituent.

The aryloxy group which may have a substituent and is represented by R is preferably an aryloxy group having 6 to 15 carbon atoms which may have a substituent, and more preferably a phenoxy group or anthracenyloxy group which may have a substituent.

The substituent that the aryloxy group represented by R may have is preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms, and further preferably a methyl group.

The optionally substituted alkylthio group represented by R is preferably an optionally substituted alkylthio group having 1 to 6 carbon atoms, more preferably an optionally substituted alkylthio group having 1 to 3 carbon atoms, further preferably an optionally substituted methylthio group or propylthio group.

The arylthio group which may have a substituent and is represented by R is preferably an arylthio group having 6 to 10 carbon atoms which may have a substituent, and more preferably a phenylthio group which may have a substituent.

The substituent that the arylthio group represented by R may have is preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms, and further preferably a methyl group.

The monovalent heterocyclic group which may have a substituent represented by R is preferably a 5-membered or 6-membered monovalent heterocyclic group which may have a substituent. Examples of the 5-membered monovalent heterocyclic group include thienyl, furanyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, isothiazolyl, oxazolyl, isoxazolyl and pyrrolidinyl. Examples of the 6-membered monovalent heterocyclic group include pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, piperidinyl, piperazinyl, morpholinyl and tetrahydropyranyl.

The monovalent heterocyclic group which may have a substituent represented by R is more preferably a thienyl group, a furyl group, a thiazolyl group, an oxazolyl group, a pyridyl group or a pyrazinyl group, and these groups may have a substituent.

The substituent that the monovalent heterocyclic group represented by R may have is preferably an alkyl group having 1 to 12 carbon atoms (for example, a methyl group, a trifluoromethyl group, a propyl group, a hexyl group, an octyl group, and a dodecyl group).

The optionally substituted alkenyl group represented by R is preferably an optionally substituted alkenyl group having 2 to 10 carbon atoms, more preferably an optionally substituted alkenyl group having 2 to 6 carbon atoms, and further preferably an optionally substituted 2-propenyl group or 5-hexenyl group.

The cycloalkenyl group which may have a substituent and is represented by R is preferably a cycloalkenyl group having 3 to 10 carbon atoms which may have a substituent, more preferably a cycloalkenyl group having 6 to 7 carbon atoms which may have a substituent, and further preferably a cyclohexenyl group or cycloheptenyl group which may have a substituent.

The substituent that the cycloalkenyl group represented by R may have is preferably an alkyl group having 1 to 12 carbon atoms.

The alkynyl group which may have a substituent and is represented by R is preferably an alkynyl group having 2 to 10 carbon atoms which may have a substituent, more preferably an alkynyl group having 5 to 6 carbon atoms which may have a substituent, and further preferably 5-hexynyl or 3-methyl-1-butynyl which may have a substituent.

The cycloalkynyl group which may have a substituent and is represented by R is preferably a cycloalkynyl group having 6 to 10 carbon atoms which may have a substituent, more preferably a cycloalkynyl group having 7 to 8 carbon atoms which may have a substituent, and further preferably a cycloheptynyl group or cyclooctynyl group which may have a substituent.

The substituent that the cycloalkynyl group represented by R may have is preferably a C1-C12 alkyl group.

The multiple R groups present are each independently preferably an alkyl group which may have a substituent, more preferably an alkyl group having 1 to 15 carbon atoms which may have a substituent, further preferably an alkyl group having 1 to 12 carbon atoms which may have a substituent, and further preferably an alkyl group having 1 to 10 carbon atoms which may have a substituent. It is particularly preferred that the multiple R groups present are all alkyl groups having 1 to 10 carbon atoms which may have a substituent.

In the group represented by -C(＝O)-Ra and the group represented by _-SO2 - ^Rb represented by ^R , ^Ra is preferably a hydrogen atom, and ^Rb is preferably an alkyl group which may have a substituent or an alkoxy group which may have a substituent, more preferably an alkyl group having 1 to 12 carbon atoms which may have a substituent or an alkoxy group having 1 to 12 carbon atoms which may have a substituent, further preferably an alkyl group having 1 to 12 carbon atoms which may have a substituent or an alkoxy group having 1 to 6 carbon atoms which may have a substituent, further preferably a methyl group, an ethyl group, a 2-methylpropyl group, an octyl group, a dodecyl group or an ethoxy group, and these groups may have a substituent.

Examples of the structural unit represented by formula (III) include structural units represented by the following formulae.

[Chemical formula 12]

[Chemical formula 13]

[Chemical formula 14]

In the above formula, R is as described above.

The structural unit represented by the above formula (III) which can constitute ^B1 is preferably a structural unit represented by the following formula (IV).

[Chemical formula 15]

In formula (IV), Y and R are as described above. ^X1 and ^X2 each independently represent a sulfur atom or an oxygen atom, and ^Z1 and ^Z2 each independently represent a group represented by =C(R)- or a nitrogen atom.

Examples of the structural unit represented by formula (IV) include structural units represented by the following formulae.

[Chemical formula 16]

The structural unit represented by the above formula (IV) which can constitute ^B1 is preferably a structural unit represented by the following formula (IV-1) which is a divalent polycyclic condensed ring group containing two or more thiophene rings and sp3 carbon atoms as constituent elements and which may have a substituent.

[Chemical formula 17]

In formula (IV-1), Y and R are as defined above.

Preferred specific examples of the structural unit represented by the above formula (IV-1) include structural units represented by the following formulae.

[Chemical formula 18]

The structural unit represented by the formula (IV) that can constitute ^B1 may be a structural unit represented by the following formula (IV-2).

[Chemical formula 19]

In the formula (IV-2), ^X1 and ^X2 , ^Z1 and ^Z2 , and R are as described above.

Examples of the structural unit represented by the formula (IV-2) include structural units represented by the following formulae (IV-2-1) to (IV-2-16).

[Chemical formula 20]

Preferred specific examples of the structural unit represented by formula (IV-2) include structural units represented by the following formulae.

[Chemical formula 21]

In the compound of this embodiment, ^B1 preferably includes one structural unit represented by the above formula (III) or formula (IV) (hereinafter referred to as the first structural unit CU1).

Examples of the structural unit that ^B1 may contain other than the structural unit represented by the above formula (III) or (IV) (hereinafter referred to as the second structural unit CU2) include a divalent group containing an unsaturated bond, a divalent aromatic carbocyclic group, and a divalent aromatic heterocyclic group.

Examples of the "divalent group containing an unsaturated bond" as the second structural unit CU2 include a group represented by -(CR=CR)n- (R is as defined above, and n is an integer greater than 1. The value of n is preferably 1 or 2, more preferably 1), a group represented by -C≡C-, and a phenylene group.

Specific examples of the "divalent group containing an unsaturated bond" include ethylene-1,2-diyl group, 1,3-butadiene-1,4-diyl group, acetylene-1,2-diyl group, and phenylene group.

Specific examples of the "divalent aromatic heterocyclic group" of the second structural unit CU2 include groups represented by the following formulae (101) to (191). These groups may further have a substituent.

[Chemical formula 22]

[Chemical formula 23]

[Chemical formula 24]

[Chemical formula 25]

In formula (101) to formula (191), R has the same meaning as above.

Specific examples of the "divalent aromatic carbon ring group" of the second structural unit CU2 include phenylene (for example, the following formulas 1 to 3), naphthalene-diyl (for example, the following formulas 4 to 13), anthracene-diyl (for example, the following formulas 14 to 19), biphenyl-diyl (for example, the following formulas 20 to 25), terphenyl-diyl (for example, the following formulas 26 to 28), condensed ring compound groups (for example, the following formulas 29 to 35), fluorene-diyl (for example, the following formulas 36 to 38) and benzofluorene-diyl (for example, the following formulas 39 to 46).

[Chemical formula 26]

[Chemical formula 27]

[Chemical formula 28]

[Chemical formula 29]

[Chemical formula 30]

[Chemical formula 31]

[Chemical formula 32]

[Chemical formula 33]

In Formulae 1 to 46, R has the same meaning as above.

In the compound of this embodiment, the second structural unit CU2 is preferably a structural unit selected from a divalent group containing an unsaturated bond and a group represented by the following formula (V-1) to (V-12), among which a structural unit selected from the groups represented by formula (V-10) to (V-12) is more preferred.

[Chemical formula 34]

In formula (V-1) to formula (V-12), X ¹ , X ² , Z ¹ , Z ² and R are as defined above.

When there are two Rs, the two Rs may be the same as or different from each other.

More specific preferred examples of the second structural unit CU2 include structural units represented by the following formulae: These structural units may further have a substituent.

[Chemical formula 35]

In the compound of this embodiment, ^B1 includes one or more structural units, at least one of the one or more structural units is a first structural unit CU1, and the remaining structural units other than the first structural unit CU1 are second structural units CU2.

The combination and arrangement of the first structural unit CU1 and the second structural unit CU2 contained in ^B1 are not particularly limited as long as a π-conjugated system can be formed.

^B1 is preferably a divalent group having any one structure selected from the groups represented by the following formula (VI-1) to formula (VI-16).

-CU1-(VI-1)

-CU1-CU1-(VI-2)

-CU1-CU2-(VI-3)

-CU1-CU1-CU1-(VI-4)

-CU1-CU2-CU1-(VI-5)

-CU1-CU1-CU2-(VI-6)

-CU1-CU2-CU2-(VI-7)

-CU2-CU1-CU2-(VI-8)

-CU1-CU1-CU1-CU1-(VI-9)

-CU1-CU1-CU1-CU2-(VI-10)

-CU1-CU1-CU2-CU1-(VI-11)

-CU1-CU1-CU2-CU2-(VI-12)

-CU1-CU2-CU1-CU2-(VI-13)

-CU1-CU2-CU2-CU1-(VI-14)

-CU1-CU2-CU2-CU2-(VI-15)

-CU2-CU1-CU2-CU2-(VI-16)

In formula (VI-1) to formula (VI-16),

CU1 represents the first structural unit CU1,

CU2 represents the second structural unit CU2.

When there are two or more CU1s, the two or more CU1s may be the same or different from each other, and when there are two or more CU2s, the two or more CU2s may be the same or different from each other. However, formula (VI-8) does not include the case where the two CU2s are the same.

Among the above formulas (VI-1) to (VI-16), preferred are divalent groups having structures represented by formulas (VI-1) to (VI-8), (VI-15) and (VI-16), and more preferred are divalent groups having structures represented by formulas (VI-1), (VI-3), (VI-7), (VI-8), (VI-15) and (VI-16).

The total number of the first structural unit CU1 and the second structural unit CU2 that can be included in ^B1 is usually 1 or more, preferably 2 or more, more preferably 3 or more, and is usually 7 or less, preferably 5 or less, more preferably 4 or less.

The number of the first structural unit CU1 that can be contained in ^B1 is usually 5 or less, preferably 3 or less, and more preferably 1.

The number of the second structural units CU2 that can be included in ^B1 is usually 5 or less, preferably 3 or less, and more preferably 1 or less.

Specific preferred examples of ^B1 include divalent groups represented by the following formula.

[Chemical formula 36]

[Chemical formula 37]

[Chemical formula 38]

[Chemical formula 39]

[Chemical formula 40]

[Chemical formula 41]

In the formula, R is as defined above.

(3) About ^D1

In the compound of the present embodiment, ^D1 is a monovalent group which is an electron donating group.

Specifically, ^D1 is a monovalent group having a function of further increasing the electron density of ^{B1, which} is a divalent group constituting a π-conjugated system. In the compound of this embodiment, the energy level of HOMO of ^D1 is preferably smaller than the energy level of HOMO of ^A1 .

In the present embodiment, examples of the electron-donating group as ^D1 include a monovalent group containing an unsaturated bond, a monovalent aromatic carbocyclic group, a monovalent aromatic heterocyclic group, an alkylamino group which may have a substituent, an arylamino group which may have a substituent, an arylalkoxy group which may have a substituent, and an arylthioalkoxy group which may have a substituent.

Specific examples of the "monovalent group containing an unsaturated bond" of the electron-donating group include a vinyl group, a 1,3-butadien-1-yl group, and an ethynyl group.

Examples of "monovalent aromatic carbocyclic group" and "monovalent aromatic heterocyclic group" as electron-donating groups include atomic groups remaining after removing one hydrogen atom directly bonded to atoms constituting a ring from a triarylamine derivative; aryl groups; and atomic groups remaining after removing one hydrogen atom directly bonded to atoms constituting a ring from a 5-membered heterocyclic ring such as a thiophene ring, a furan ring, a pyrrole ring, a cyclopentadiene, a silocyclopentadiene, or a structure containing them as a condensed ring.

Here, examples of the triarylamine derivative include triphenylamine, dinaphthylphenylamine, bis(4-alkylphenyl)phenylamine, bis(4-alkoxyphenyl)phenylamine, bis(9,9-dimethylfluoren-2-yl)phenylamine, diphenylthienylamine, bis(4-alkylphenyl)thienylamine, bis(4-alkoxyphenyl)thienylamine, bis(9,9-dimethylfluoren-2-yl)thienylamine, etc. Preferred are triphenylamine, bis(4-alkylphenyl)phenylamine, and bis(4-alkoxyphenyl)phenylamine.

Examples of the carbazole derivative include carbazole, 9-alkylcarbazole, 9-arylcarbazole, and the like. Specifically, carbazole, 9-ethylcarbazole, 9-phenylcarbazole, 9-fluorenylcarbazole, and the like are mentioned. Carbazole is preferred.

As the aryl group which may have a substituent, for example, phenyl, 4-alkoxyphenyl, 4-tetraethylene glycoloxyphenyl (Japanese: 4-tetraethylene glycoloxyphenyl), 3,4,5-trialkoxyphenyl, dimethylaminophenyl, diethylaminophenyl, pyrrolylphenyl, thienyl, alkylthienyl, alkoxythienyl, ethylenedioxythienyl, phenothiazinyl, thianthrenyl (Japanese: チアントレニル基). As the alkyl group of the alkylthienyl group and the alkoxy group of the alkoxythienyl group, the groups already described can be mentioned. In addition, a plurality of aryl groups in the aryl group may be linked. As the aryl group, diethylaminophenyl, 3,4,5-trialkoxyphenyl, and ethylenedioxythienyl are preferred.

Examples of the optionally substituted alkylamino group include alkylamino groups having 1 to 8 carbon atoms, such as methylamino, ethylamino, isopropylamino, n-butylamino, dimethylamino, diethylamino and diisopropylamino, and dimethylamino is preferred.

Examples of the arylamino group which may have a substituent include a phenylamino group, a naphthylamino group, a diphenylamino group, a di-4-ethylphenylamino group, and a di-4-methylphenylamino group, and a diphenylamino group is preferred.

Examples of the arylalkoxy group which may have a substituent include phenyl, 4-alkoxyphenyl, 4-hexyloxyphenyl, 4-tetraethylene glycoloxyphenyl, 3,4,5-trialkoxyphenyl, dimethylaminophenyl, diethylaminophenyl, and pyrrolylphenyl as an aryl group which may have a substituent. The arylalkoxy group is preferably a phenoxy group or a 4-hexyloxyphenoxy group.

Examples of the arylthioalkoxy group which may have a substituent include phenyl, 4-alkoxyphenyl, 4-hexyloxyphenyl, 4-tetraethylene glycoloxyphenyl, 3,4,5-trialkyloxyphenyl, dimethylaminophenyl, diethylaminophenyl, and pyrrolylphenyl groups as the aryl group which may have a substituent. The aryl group in the arylthioalkoxy group is preferably 4-hexyloxyphenyl.

Examples of 5-membered heterocyclic rings such as thiophene ring, furan ring, pyrrole ring, cyclopentadiene, silacyclopentadiene, and structures containing them as condensed rings include fluorene, silafluorene, dithienopentalene, dithienosilacyclopentalene, dithienopyrrole, and benzodithiophene.

As other monovalent aromatic heterocyclic groups, groups represented by the following formulae are mentioned.

[Chemical formula 42]

Specifically, in the compound of the present embodiment, ^D1 is preferably an N-carbazolyl group, a diphenylamino group, or a phenoxy group, more preferably a group represented by the following formula, and more preferably an N-carbazolyl group, a diphenylamino group, or a group represented by the following formula.

[Chemical formula 43]

Specific examples of the compound represented by formula (I) according to the present embodiment include compounds represented by the following formulas.

[Chemical formula 44]

[Chemical formula 45]

[Chemical formula 46]

[Chemical formula 47]

[Chemical formula 48]

More specific preferred examples of the compound represented by formula (I) according to the present embodiment include compounds represented by the following formulas.

[Chemical formula 49]

In the compound represented by formula (I) which is the compound of the present embodiment, from the viewpoint of reducing dark current, it is preferred that the energy level of the LUMO of ^D1 ( _ED-LUMO ), the energy level of the LUMO of at least one structural unit among the one or more structural units constituting ^B1 (usually the first structural unit CU) ( _Eπ-LUMO ) and the energy level of the LUMO of ^A1 ( _EA-LUMO ) satisfy the conditions shown in the following formula.

E _D-LUMO ＞E _B-LUMO ＞E _A-LUMO

In the compound represented by formula (I) of the present embodiment, the LUMO energy level ( _EB-LUMO )min of the structural unit having the lowest LUMO energy level among the one or more structural units constituting ^B1 preferably satisfies the following condition.

E _D-LUMO ＞(E _B-LUMO )min＞E _A-LUMO

In the compound represented by formula (I) as the compound of this embodiment, it is preferred that the average value ( _EB-LUMO )ave of the LUMO energy levels of one or more structural units constituting ^B1 satisfies the condition represented by the following formula.

E _D-LUMO ＞(E _B-LUMO )ave＞E _A-LUMO

The energy level value (eV) of the LUMO of the structural unit ( ^D1 , ^B1 and ^A1 ) contained in the compound represented by formula (I) can be calculated by any suitable computational science method known in the art. As a computational science method, for example, the following method can be applied: using the quantum chemical calculation program Gaussian 03, the density functional method at the B3LYP level is used to perform ground state structural optimization, using 6-31g* as the basis function.

Specifically, the above method can be applied to each structure (compound) derived from each structural unit obtained by cleaving the bonds between structural units (D ¹ , B ¹ and A ¹ ) and adding hydrogen atoms to the bonds generated by the cleavage.

The compound of this embodiment can be suitably used as a semiconductor material of an active layer of a photoelectric conversion element, particularly as a non-fullerene compound as an n-type semiconductor material.

In particular, when the compound of this embodiment is used as an n-type semiconductor material for the material of the active layer, it is possible to effectively reduce the dark current required for a photoelectric conversion element as a light detection element.

Two or more compounds of this embodiment used as n-type semiconductor materials may be contained as materials for the active layer.

The active layer of the photoelectric conversion element (details are described later) may contain only the compound of the present embodiment as an n-type semiconductor material, or may contain compounds other than the compound of the present embodiment as n-type semiconductor materials as other n-type semiconductor materials. The compound other than the compound of the present embodiment that can be contained as other n-type semiconductor materials may be a low molecular weight compound or a high molecular weight compound.

Examples of n-type semiconductor materials (electron accepting compounds) other than the "compounds of the present embodiment" as low molecular weight compounds include oxadiazole derivatives, anthraquinone dimethane and its derivatives, benzoquinone and its derivatives, naphthoquinone and its derivatives, anthraquinone and its derivatives, tetracyanoanthraquinone dimethane and its derivatives, fluorenone derivatives, diphenyldicyanoethylene and its derivatives, diphenoquinone derivatives, metal complexes of 8-hydroxyquinoline and its derivatives, and phenanthrene derivatives such as bathocuproin.

Examples of n-type semiconductor materials other than the “compound of the present embodiment” as polymer compounds include polyvinylcarbazole and its derivatives, polysilane and its derivatives, polysiloxane derivatives having an aromatic amine structure in the side chain or the main chain, polyaniline and its derivatives, polythiophene and its derivatives, polypyrrole and its derivatives, polyphenylene vinylene (Japanese: ポリフェニレンビレン) and its derivatives, polythiophene acetylene (Japanese: ポリチエニレンビレン) and its derivatives, polyquinoline and its derivatives, polyquinoxaline and its derivatives, and polyfluorene and its derivatives.

Compounds other than the “compound of the present embodiment” may contain a fullerene derivative.

Here, the fullerene derivative refers to a compound in which at least a part of fullerene ( _C60 fullerene, _C70 fullerene, _C76 fullerene, _C78 fullerene and _C84 fullerene) is modified. In other words, it refers to a compound having one or more groups added to the fullerene skeleton. Hereinafter, in particular, a fullerene derivative of _C60 fullerene is sometimes referred to as a " _C60 fullerene derivative", and a fullerene derivative of _C70 fullerene is sometimes referred to as a " _C70 fullerene derivative".

Fullerene derivatives other than the "compound of the present embodiment" that can be used as an n-type semiconductor material are not particularly limited unless the object of the present invention is impaired.

Specific examples of C ₆₀ fullerene derivatives that can be used as n-type semiconductor materials other than the “compound of the present embodiment” include the following compounds.

[Chemical formula 50]

In the formula, R is as defined above. When there are multiple Rs, the multiple Rs may be the same as or different from each other.

Examples of C ₇₀ fullerene derivatives include the following compounds.

[Chemical formula 51]

2. Photoelectric conversion element

The photoelectric conversion element of this embodiment includes an anode, a cathode, and an active layer provided between the anode and the cathode and including a p-type semiconductor material and an n-type semiconductor material, and includes the compound of this embodiment described above as the n-type semiconductor material.

According to the photoelectric conversion element of this embodiment, by having the above-mentioned configuration, it is possible to effectively reduce the dark current required for the photoelectric conversion element as a light detection element in particular.

Here, a configuration example that can be adopted by the photoelectric conversion element of this embodiment will be described. Fig. 1 is a diagram schematically showing the configuration of the photoelectric conversion element of this embodiment.

As shown in FIG1 , the photoelectric conversion element 10 is provided on a supporting substrate 11. The photoelectric conversion element 10 includes an anode 12 provided in contact with the supporting substrate 11, a hole transport layer 13 provided in contact with the anode 12, an active layer 14 provided in contact with the hole transport layer 13, an electron transport layer 15 provided in contact with the active layer 14, and a cathode 16 provided in contact with the electron transport layer 15. In this configuration example, a sealing member 17 is further provided in contact with the cathode 16.

Hereinafter, constituent elements that may be included in the photoelectric conversion element of this embodiment will be described in detail.

(Substrate)

The photoelectric conversion element is usually formed on a substrate (support substrate). In addition, sometimes a substrate (sealing substrate) is used for sealing. One of a pair of electrodes consisting of an anode and a cathode is usually formed on the substrate. There is no particular limitation on the material of the substrate as long as it is a material that does not undergo chemical changes when forming a layer, especially a layer containing an organic compound.

As the material of the substrate, for example, glass, plastic, polymer film, silicon can be cited. When an opaque substrate is used, it is preferred that the electrode on the opposite side to the electrode provided on the opaque substrate side (in other words, the electrode on the side away from the opaque substrate) is a transparent or translucent electrode.

(electrode)

The photoelectric conversion element includes an anode and a cathode as a pair of electrodes. In order to allow light to enter, at least one of the anode and the cathode is preferably a transparent or semi-transparent electrode.

As examples of materials for transparent or translucent electrodes, conductive metal oxide films and translucent metal films can be cited. Specifically, conductive materials such as indium oxide, zinc oxide, tin oxide and indium tin oxide (ITO), indium zinc oxide (IZO), NESA, gold, platinum, silver, and copper as their composites can be cited. As materials for transparent or translucent electrodes, ITO, IZO, and tin oxide are preferred. In addition, as electrodes, transparent conductive films using organic compounds such as polyaniline and derivatives thereof, polythiophene and derivatives thereof as materials can be used. The transparent or translucent electrode can be an anode or a cathode.

If one of a pair of electrodes is transparent or translucent, the other electrode can be an electrode with low light transmittance. Examples of materials for electrodes with low light transmittance include metals and conductive polymers. Specific examples of materials for electrodes with low light transmittance include metals such as lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, aluminum, scandium, vanadium, zinc, yttrium, indium, cerium, samarium, europium, terbium, and ytterbium, and alloys of two or more of them; or alloys of one or more of them with one or more of the metals selected from gold, silver, platinum, copper, manganese, titanium, cobalt, nickel, tungsten, and tin; graphite, graphite intercalation compounds, polyaniline and its derivatives, polythiophene and its derivatives. As alloys, magnesium-silver alloys, magnesium-indium alloys, magnesium-aluminum alloys, indium-silver alloys, lithium-aluminum alloys, lithium-magnesium alloys, lithium-indium alloys, and calcium-aluminum alloys can be cited.

(Active layer)

The active layer of the photoelectric conversion element of this embodiment is assumed to have a bulk heterojunction structure including a p-type semiconductor material and an n-type semiconductor material, and includes the compound of this embodiment as the n-type semiconductor material (details will be described later).

In this embodiment, the thickness of the active layer is not particularly limited. Considering the balance between the suppression of dark current and the extraction of the generated photocurrent, the thickness of the active layer can be set to any appropriate thickness. In particular, from the viewpoint of further reducing the dark current, the thickness of the active layer is preferably 100 nm or more, more preferably 150 nm or more, and further preferably 200 nm or more. In addition, the thickness of the active layer is preferably 10 μm or less, more preferably 5 μm or less, and further preferably 1 μm or less.

Here, as a material for the active layer of this embodiment, a p-type semiconductor material that can be appropriately used in combination with the n-type semiconductor material as the compound of this embodiment described above will be described.

The p-type semiconductor material of the present embodiment is preferably a polymer compound having a predetermined weight average molecular weight in terms of polystyrene.

In addition, the p-type semiconductor material of the present embodiment is preferably a polymer compound having an absorption peak wavelength greater than 700 nm.

The "absorption peak wavelength" can be measured using any appropriate conventionally known ultraviolet-visible-near-infrared spectrophotometer (for example, "JASCO-V670" manufactured by JASCO Corporation).

Here, the polystyrene-equivalent weight average molecular weight refers to a weight average molecular weight calculated using a standard sample of polystyrene by gel permeation chromatography (GPC).

In particular, from the viewpoint of improving solubility in a solvent, the polystyrene-equivalent weight average molecular weight of the p-type semiconductor material is preferably 3,000 or more and 500,000 or less.

In this embodiment, the p-type semiconductor material is preferably a π-conjugated polymer compound (also called a D-A type conjugated polymer compound or simply a conjugated polymer compound) comprising a donor structural unit (also called a D structural unit) and an acceptor structural unit (also called an A structural unit). It should be noted that which one is the donor structural unit or the acceptor structural unit can be relatively determined based on the energy level of HOMO or LUMO.

Here, the donor structural unit is a structural unit having excess π electrons, and the acceptor structural unit is a structural unit having deficiency of π electrons.

In this embodiment, the structural units that can constitute the p-type semiconductor material also include structural units formed by direct bonding of donor structural units and acceptor structural units, and structural units formed by bonding of donor structural units and acceptor structural units via any suitable spacer (group or structural unit).

Regarding p-type semiconductor materials as polymer compounds, for example, polyvinylcarbazole and its derivatives, polysilane and its derivatives, polysiloxane derivatives containing an aromatic amine structure in the side chain or the main chain, polyaniline and its derivatives, polythiophene and its derivatives, polypyrrole and its derivatives, polyphenylene vinylene and its derivatives, polythiophene vinylene and its derivatives, polyfluorene and its derivatives.

The polymer compound including the structural unit represented by the following formula (VII) in the present embodiment is preferred. The structural unit represented by the following formula (VII) is usually a donor structural unit in the present embodiment.

[Chemical formula 52]

In formula (VII), Ar ³ and Ar ⁴ represent a trivalent aromatic heterocyclic group which may have a substituent, and Z represents a group represented by the following formulae (Z-1) to (Z-7).

[Chemical formula 53]

In formulas (Z-1) to (Z-7),

R is as defined above.

In each group of formula (Z-1) to formula (Z-7), when there are two Rs, the two Rs may be the same as or different from each other.

The aromatic heterocyclic rings which may constitute ^Ar3 and ^Ar4 include not only monocyclic rings and condensed rings in which the heterocyclic ring itself is aromatic, but also rings in which an aromatic ring is condensed to a heterocyclic ring even though the heterocyclic ring constituting the ring itself is not aromatic.

The aromatic heterocycles that can constitute ^Ar3 and ^Ar4 can be monocyclic or condensed rings. When the aromatic heterocycles are condensed rings, the rings constituting the condensed rings can all be condensed rings with aromaticity, or can be condensed rings with only a portion of aromaticity. When these rings have multiple substituents, these substituents can be the same or different.

Specific examples of the aromatic carbon ring that can constitute Ar ³ and Ar ⁴ include a benzene ring, a naphthalene ring, an anthracene ring, a tetracene ring, a pentacene ring, a pyrene ring, and a phenanthrene ring, preferably a benzene ring and a naphthalene ring, more preferably a benzene ring and a naphthalene ring, and further preferably a benzene ring. These rings may have a substituent.

As specific examples of aromatic heterocycles, ring structures possessed by compounds described as aromatic heterocyclic compounds can be cited, and examples thereof include oxadiazole rings, thiadiazole rings, thiazole rings, oxazole rings, thiophene rings, pyrrole rings, phosphole rings, furan rings, pyridine rings, pyrazine rings, pyrimidine rings, triazine rings, pyridazine rings, quinoline rings, isoquinoline rings, carbazole rings, dibenzophosphole rings, and phenoxazine rings, phenothiazine rings, dibenzoborole rings, dibenzosilole rings, and benzopyran rings. These rings may have substituents.

The structural unit represented by formula (VII) is preferably a structural unit represented by the following formula (VIII) or (IX). In other words, in this embodiment, the p-type semiconductor material is preferably a polymer compound including a structural unit represented by the following formula (VIII) or (IX).

[Chemical formula 54]

In formulae (VIII) and (IX), Ar ³ , Ar ⁴ and R are as defined above.

Examples of suitable structural units represented by formulae (VII) and (IX) include structural units represented by the following formulae (VII-1) and (VII-2) and formulae (IX-1) and (IX-2).

[Chemical formula 55]

In formula (VII-1), formula (VII-2), formula (IX-1) and formula (IX-2),

R is as defined above.

When there are two Rs, the two Rs may be the same or different.

More specific preferred examples of the structural unit represented by formula (VII-1) include structural units represented by the following formulas (VII-1-1) and (VII-1-2).

[Chemical formula 56]

In addition, the structural unit represented by formula (VIII) is preferably a structural unit represented by the following formula (X). In other words, in this embodiment, the p-type semiconductor material may be a polymer compound including the structural unit represented by the following formula (X).

[Chemical formula 57]

In formula (X),

^X1 and ^X2 are each independently a sulfur atom or an oxygen atom,

^Z1 and ^Z2 are each independently a group represented by =C(R)- or a nitrogen atom,

R is as defined above.

Preferred examples of the structural unit represented by formula (IX) include structural units represented by the following formulae (X-1) to (X-16).

[Chemical formula 58]

As the structural unit represented by the formula (X), a structural unit in which ^X1 and ^X2 are sulfur atoms and ^Z1 and ^Z2 are groups represented by =C(R)- is preferred.

In the present embodiment, the polymer compound as the p-type semiconductor material preferably includes a structural unit represented by the following formula (XI). The structural unit represented by the following formula (XI) is usually an acceptor structural unit in the present embodiment.

[Chemical formula 59]

-Ar ⁵ -(XⅠ)

In the formula (XI), Ar ⁵ represents a divalent aromatic heterocyclic group.

The divalent aromatic heterocyclic group represented by Ar ⁵ has usually 2 to 60 carbon atoms, preferably 4 to 60 carbon atoms, and more preferably 4 to 20 carbon atoms.

The divalent aromatic heterocyclic group represented by Ar ^{5 may have a substituent. Examples of the substituent that the divalent aromatic heterocyclic group represented by Ar 5 may} have include a halogen atom, an alkyl group that may have a substituent, an aryl group that may have a substituent, an alkoxy group that may have a substituent, an aryloxy group that may have a substituent, an alkylthio group that may have a substituent, an arylthio group that may have a substituent, a monovalent heterocyclic group that may have a substituent, a substituted amino group that may have a substituent, an acyl group that may have a substituent, an imine residue that may have a substituent, an amide group that may have a substituent, an imide group that may have a substituent, a substituted oxycarbonyl group that may have a substituent, an alkenyl group that may have a substituent, an alkynyl group that may have a substituent, a cyano group, and a nitro group.

As the structural unit represented by the formula (X), structural units represented by the following formulae (X-1) to (X-10) are preferred.

[Chemical formula 60]

In formula (X-1) to formula (X-10),

X ¹ , X ² , Z ¹ , Z ² and R are as defined above.

When there are two Rs, the two Rs may be the same as or different from each other.

From the viewpoint of availability of raw material compounds, ^X1 and ^X2 in Formula (X-1) to Formula (X-10) are preferably both sulfur atoms.

It should be noted that the structural units represented by formula (X-1) to formula (X-10) can generally function as acceptor structural units as described above. However, this is not limited to this, and in particular, the structural units represented by formula (X-4), formula (X-5) and formula (X-7) can also function as donor structural units.

In the present embodiment, the p-type semiconductor material is preferably a π-conjugated polymer compound including a structural unit containing a thiophene skeleton and including a π-conjugated system.

Specific examples of the divalent aromatic heterocyclic group represented by Ar ⁵ include groups represented by the following formulae (101) to (191). These groups may further have a substituent.

[Chemical formula 61]

[Chemical formula 62]

[Chemical formula 63]

[Chemical formula 64]

In formulae (101) to (191), R has the same meaning as above. When there are multiple Rs, the multiple Rs may be the same as or different from each other.

The polymer compound as the p-type semiconductor material of the present embodiment is preferably a π-conjugated polymer compound including a structural unit represented by formula (VI) as a donor structural unit and a structural unit represented by formula (X) as an acceptor structural unit.

The polymer compound as a p-type semiconductor material may contain two or more structural units represented by formula (VI), or may contain two or more structural units represented by formula (X).

For example, from the viewpoint of improving solubility in a solvent, the polymer compound as a p-type semiconductor material of the present embodiment may include a structural unit represented by the following formula (XII).

[Chemical formula 65]

-Ar ⁶ -(XII)

In the formula (XII), Ar ⁶ represents a divalent aromatic carbocyclic group.

The divalent aromatic carbocyclic group represented by Ar ⁶ refers to an atomic group remaining after removing two hydrogen atoms from an aromatic hydrocarbon which may have a substituent. Aromatic hydrocarbons also include compounds having a condensed ring, and compounds in which two or more selected from independent benzene rings and condensed rings are bonded directly or through a divalent group such as vinylene.

Examples of the substituent which the aromatic hydrocarbon may have include the same substituents as exemplified as the substituent which the heterocyclic compound may have.

The number of carbon atoms of the divalent aromatic carbocyclic group represented by Ar ⁶ is not including the number of carbon atoms of the substituent, and is usually 6 to 60, preferably 6 to 20. The number of carbon atoms including the substituent is usually 6 to 100.

Examples of the divalent aromatic carbocyclic group represented by Ar ⁶ include phenylene (for example, the following formulas 1 to 3), naphthalene-diyl (for example, the following formulas 4 to 13), anthracene-diyl (for example, the following formulas 14 to 19), biphenyl-diyl (for example, the following formulas 20 to 25), terphenyl-diyl (for example, the following formulas 26 to 28), condensed ring compound groups (for example, the following formulas 29 to 35), fluorene-diyl (for example, the following formulas 36 to 38) and benzofluorene-diyl (for example, the following formulas 39 to 46).

[Chemical formula 66]

[Chemical formula 67]

[Chemical formula 68]

[Chemical formula 69]

[Chemical formula 70]

[Chemical formula 71]

[Chemical formula 72]

[Chemical formula 73]

In the formula, R is as defined above. A plurality of Rs present may be the same as or different from each other.

The structural unit represented by formula (XII) is preferably a structural unit represented by the following formula (XIII).

[Chemical formula 74]

In formula (XIII), R is as defined above. The two Rs present may be the same as or different from each other.

The structural unit constituting the polymer compound serving as a p-type semiconductor material may be a structural unit in which two or more structural units selected from the above structural units are combined and linked.

In the case where a polymer compound serving as a p-type semiconductor material contains a structural unit represented by formula (VI) and/or a structural unit represented by formula (X), when the amount of all structural units contained in the polymer compound is set to 100 mol %, the total amount of the structural unit represented by formula (VI) and the structural unit represented by formula (X) is generally 20 mol % to 100 mol %, preferably 40 mol % to 100 mol %, and more preferably 50 mol % to 100 mol % for the purpose of improving the charge transport properties as a p-type semiconductor material.

Specific examples of the polymer compound serving as the p-type semiconductor material of the present embodiment include polymer compounds represented by the following formulae (P-1) to (P-17).

[Chemical formula 75]

[Chemical formula 76]

[Chemical formula 77]

[Chemical formula 78]

[Chemical formula 79]

[Chemical formula 80]

[Chemical formula 81]

In the formula, R is as defined above. The multiple Rs present may be the same or different from each other.

When the polymer compound exemplified above is used as a p-type semiconductor material, it is possible to effectively reduce a dark current required for a photoelectric conversion element as a light detection element.

(Middle layer)

As shown in FIG. 1 , the photoelectric conversion element of this embodiment preferably includes an intermediate layer (buffer layer) such as a charge transport layer (electron transport layer, hole transport layer, electron injection layer, hole injection layer) as a component for improving characteristics such as photoelectric conversion efficiency.

Examples of materials used in the intermediate layer include metals such as calcium, inorganic oxide semiconductors such as molybdenum oxide and zinc oxide, and a mixture of PEDOT (poly(3,4-ethylenedioxythiophene)) and PSS (poly(4-styrenesulfonate)) (PEDOT:PSS).

As shown in Fig. 1 , the photoelectric conversion element preferably includes a hole transport layer between the anode and the active layer. The hole transport layer has a function of transporting holes from the active layer to the electrode.

The hole transport layer provided in contact with the anode is sometimes specifically referred to as a hole injection layer. The hole transport layer (hole injection layer) provided in contact with the anode has the function of promoting the injection of holes into the anode. The hole transport layer (hole injection layer) may be in contact with the active layer.

The hole transport layer contains a hole transport material. Examples of the hole transport material include polythiophene and its derivatives, aromatic amine compounds, polymer compounds containing a structural unit having an aromatic amine residue, CuSCN, CuI, NiO, tungsten oxide (WO ₃ ) and molybdenum oxide (MoO ₃ ).

The intermediate layer can be formed by any conventionally known appropriate formation method. The intermediate layer can be formed by a vacuum deposition method or a coating method similar to the formation method of the active layer.

The photoelectric conversion element of this embodiment preferably has a structure in which the intermediate layer is an electron transport layer, and a substrate (support substrate), an anode, a hole transport layer, an active layer, an electron transport layer, and a cathode are sequentially stacked in contact with each other.

As shown in FIG1 , the photoelectric conversion element of this embodiment preferably has an electron transport layer as an intermediate layer between the cathode and the active layer. The electron transport layer has the function of transporting electrons from the active layer to the cathode. The electron transport layer may be in contact with the cathode. The electron transport layer may be in contact with the active layer.

The electron transport layer provided in contact with the cathode is sometimes particularly referred to as an electron injection layer. The electron transport layer (electron injection layer) provided in contact with the cathode has a function of promoting the injection of electrons generated in the active layer into the cathode.

The electron transport layer contains an electron transport material. Examples of the electron transport material include polyalkyleneimine and its derivatives, polymer compounds containing a fluorene structure, metals such as calcium, and metal oxides.

Examples of polyalkyleneimines and their derivatives include polymers obtained by polymerizing one or more of alkyleneimines having 2 to 8 carbon atoms, particularly alkyleneimines having 2 to 4 carbon atoms, such as ethyleneimine, propyleneimine, butyleneimine, dimethylethyleneimine, pentyleneimine, hexyleneimine, heptyleneimine, and octyleneimine by conventional methods, and polymers obtained by chemically modifying these alkyleneimines by reacting them with various compounds. Polyalkyleneimines and their derivatives are preferably polyethyleneimine (PEI) and ethoxylated polyethyleneimine (PEIE).

Examples of polymer compounds containing a fluorene structure include poly[(9,9-bis(3'-(N,N-dimethylamino)propyl)-2,7-fluorene)-o-2,7-(9,9'-dioctylfluorene)] (PFN) and PFN-P2.

Examples of the metal oxide include zinc oxide, gallium-doped zinc oxide, aluminum-doped zinc oxide, titanium oxide, and niobium oxide. As the metal oxide, a metal oxide containing zinc is preferred, and zinc oxide is preferred among them.

Examples of other electron transporting materials include poly(4-vinylphenol) and perylene diimide.

(Sealing member)

The photoelectric conversion element of this embodiment further includes a sealing member, and is preferably formed into a sealed body sealed by the sealing member.

Any suitable conventionally known member can be used as the sealing member. Examples of the sealing member include a combination of a glass substrate as a substrate (sealing substrate) and a sealing material (adhesive) such as a UV curable resin.

The sealing member may be a sealing layer having a layer structure of one or more layers. Examples of the layer constituting the sealing layer include a gas barrier layer and a gas barrier film.

The sealing layer is preferably formed of a material having a property of blocking moisture (water vapor barrier property) or a property of blocking oxygen (oxygen barrier property). Examples of suitable materials for the sealing layer include organic materials such as trifluoroethylene, polychlorotrifluoroethylene (PCTFE), polyimide, polycarbonate, polyethylene terephthalate, alicyclic polyolefin, ethylene-vinyl alcohol copolymer, and inorganic materials such as silicon oxide, silicon nitride, aluminum oxide, and diamond-like carbon.

The sealing member is generally made of a material that can withstand a heat treatment performed when the sealing member is assembled into a device to which the photoelectric conversion element is applied, for example, in the following application example.

(3) Application of photoelectric conversion elements

Examples of applications of the photoelectric conversion element of this embodiment include a light detection element and a solar cell.

More specifically, the photoelectric conversion element of this embodiment can flow photocurrent by irradiating light from the transparent or translucent electrode side while applying a voltage (reverse bias voltage) between the electrodes, and can work as a light detection element (light sensor). In addition, it can also be used as an image sensor by integrating multiple light detection elements. The photoelectric conversion element of this embodiment can be particularly suitable for use as a light detection element.

In addition, the photoelectric conversion element of this embodiment can generate a photovoltaic force between electrodes by being irradiated with light, and can operate as a solar cell. A plurality of photoelectric conversion elements can also be integrated to form a solar cell module.

(4) Application examples of photoelectric conversion elements

The photoelectric conversion element of this embodiment can be suitably used as a light detection element in detection units included in various electronic devices such as workstations, personal computers, portable information terminals, room entry and exit management systems, digital cameras, and medical equipment.

The photoelectric conversion element of this embodiment can be appropriately applied to image detection units (e.g., image sensors such as X-ray sensors) for solid-state imaging devices such as X-ray imaging devices and CMOS image sensors, detection units (e.g., near-infrared sensors) of biological information recognition devices that detect specific features of a part of a biological body, such as fingerprint detection units, face detection units, vein detection units, and iris detection units, and detection units of optical biosensors such as pulse oximeters, etc., which are possessed by the electronic devices exemplified above.

The photoelectric conversion element of this embodiment can be further suitably applied to a time-of-flight (TOF) distance measuring device (TOF distance measuring device) as an image detection unit for a solid-state imaging device.

In a TOF type distance measuring device, the distance is measured by using a photoelectric conversion element to receive the reflected light reflected by the radiated light from the light source in the measured object. Specifically, the flight time from the radiated light emitted from the light source to the measured object and returned as reflected light is detected to find the distance to the measured object. There are direct TOF methods and indirect TOF methods in the TOF type. In the direct TOF method, the difference between the time when the light is radiated from the light source and the time when the reflected light is received by the photoelectric conversion element is directly measured. In the indirect TOF method, the distance is measured by converting the change in the charge accumulation amount that depends on the flight time into a time change. In the distance measurement principle of obtaining the flight time by charge accumulation used in the indirect TOF method, there are continuous wave (especially sine wave) modulation methods and pulse modulation methods that calculate the flight time based on the phase of the radiated light from the light source and the reflected light reflected by the measured object.

Hereinafter, with reference to the accompanying drawings, examples of the configuration of an image detection unit for a solid-state imaging device and an image detection unit for an X-ray imaging device, a fingerprint detection unit and a vein detection unit for a biometric identification device (for example, a fingerprint identification device, a vein identification device, etc.), and an image detection unit for a TOF type ranging device (indirect TOF method) among the detection units to which the photoelectric conversion element of the present embodiment can be appropriately applied, are described.

(Image detection unit for solid-state imaging device)

FIG. 2 is a diagram schematically showing a configuration example of an image detection unit for a solid-state imaging device.

The image detection unit 1 includes: a CMOS transistor substrate 20; an interlayer insulating film 30 arranged in a manner covering the CMOS transistor substrate 20; a photoelectric conversion element 10 of an embodiment of the present invention arranged on the interlayer insulating film 30; an interlayer wiring portion 32 arranged in a manner penetrating the interlayer insulating film 30 and electrically connecting the CMOS transistor substrate 20 and the photoelectric conversion element 10; a sealing layer 40 arranged in a manner covering the photoelectric conversion element 10; and a color filter 50 arranged on the sealing layer 40.

The CMOS transistor substrate 20 has any suitable configuration known in the art in accordance with the design.

The CMOS transistor substrate 20 includes functional elements such as transistors and capacitors formed within the thickness of the substrate and CMOS transistor circuits (MOS transistor circuits) for realizing various functions.

Examples of the functional element include a floating diffusion element, a reset transistor, an output transistor, and a selection transistor.

A signal readout circuit and the like are fabricated on the CMOS transistor substrate 20 by means of such functional elements, wirings and the like.

The interlayer insulating film 30 may be made of any suitable insulating material known in the past, such as silicon oxide, insulating resin, etc. The interlayer wiring portion 32 may be made of any suitable conductive material (wiring material) known in the past, such as copper, tungsten, etc. The interlayer wiring portion 32 may be, for example, an in-hole wiring formed simultaneously with the formation of the wiring layer, or may be a buried plug formed separately from the wiring layer.

The sealing layer 40 can be made of any suitable material known in the art, provided that it can prevent or suppress the penetration of harmful substances such as oxygen and water that may deteriorate the functionality of the photoelectric conversion element 10. The sealing layer 40 can be made of the same structure as the sealing member 17 described above.

As the color filter 50, for example, a primary color filter made of any suitable material known in the past and corresponding to the design of the image detection unit 1 can be used. In addition, as the color filter 50, a complementary color filter that can be thinner than the primary color filter can also be used. As the complementary color filter, for example, a color filter composed of three colors (yellow, cyan, magenta), three colors (yellow, cyan, transparent), three colors (yellow, transparent, magenta) and three colors (transparent, cyan, magenta) can be used. They can be set to any suitable configuration corresponding to the design of the photoelectric conversion element 10 and the CMOS transistor substrate 20, with the condition that they can generate color image data.

The light received by the photoelectric conversion element 10 through the color filter 50 is converted into an electrical signal according to the amount of received light by the photoelectric conversion element 10 and output to the outside of the photoelectric conversion element 10 through the electrode as a light reception signal, that is, an electrical signal corresponding to the object.

Next, the light-receiving signal output from the photoelectric conversion element 10 is input to the CMOS transistor substrate 20 via the interlayer wiring portion 32, read out by a signal readout circuit manufactured on the CMOS transistor substrate 20, and processed by any other suitable previously known functional portion not shown, thereby generating image information based on the photographed object.

(Fingerprint Detection Unit)

FIG. 3 is a diagram schematically showing a configuration example of a fingerprint detection unit configured integrally with a display device.

The display device 2 of the portable information terminal includes a fingerprint detection unit 100 including the photoelectric conversion element 10 according to the embodiment of the present invention as a main component, and a display panel unit 200 provided on the fingerprint detection unit 100 and displaying a predetermined image.

In this configuration example, the fingerprint detection unit 100 is provided in a region that coincides with the display region 200 a of the display panel unit 200 . In other words, the display panel unit 200 is integrally stacked above the fingerprint detection unit 100 .

When fingerprint detection is performed only in a part of the display area 200 a , the fingerprint detection unit 100 may be provided only corresponding to the part of the area.

The fingerprint detection unit 100 includes the photoelectric conversion element 10 of the embodiment of the present invention as a functional unit that performs substantial functions. The fingerprint detection unit 100 may include any suitable conventionally known components such as a protection film (not shown), a support substrate, a sealing substrate, a sealing member, a barrier film, a bandpass filter, and an infrared cutoff film in a manner corresponding to the design to obtain the desired characteristics. The fingerprint detection unit 100 may also adopt the configuration of the image detection unit described above.

The photoelectric conversion element 10 may be included in the display region 200a in any manner. For example, a plurality of photoelectric conversion elements 10 may be arranged in a matrix.

As described above, the photoelectric conversion element 10 is provided on the supporting substrate 11 , and the electrodes (first electrodes or second electrodes) are provided on the supporting substrate 11 in a matrix form, for example.

The light received by the photoelectric conversion element 10 is converted into an electrical signal according to the amount of light received by the photoelectric conversion element 10 and output to the outside of the photoelectric conversion element 10 via the electrode in the form of a light reception signal, that is, an electrical signal corresponding to the photographed fingerprint.

In this configuration example, the display panel unit 200 is configured as an organic electroluminescent display panel (organic EL display panel) including a touch sensor panel. The display panel unit 200 may be configured as a display panel having any suitable conventionally known configuration, such as a liquid crystal display panel including a light source such as a backlight, instead of the organic EL display panel.

The display panel unit 200 is provided on the fingerprint detection unit 100 described above. The display panel unit 200 includes an organic electroluminescent element (organic EL element) 220 as a functional unit that performs substantial functions. The display panel unit 200 may further include any suitable substrate (support substrate 210 or sealing substrate 240) such as a glass substrate, a sealing member, a barrier film, a polarizing plate such as a circular polarizing plate, a touch sensor panel 230, and any other suitable components known in the past in a manner corresponding to the desired characteristics.

In the configuration example described above, the organic EL element 220 is used as a light source for pixels in the display region 200 a and is also used as a light source for capturing a fingerprint in the fingerprint detection unit 100 .

Here, the operation of the fingerprint detection unit 100 will be briefly described.

When performing fingerprint recognition, the fingerprint detection unit 100 detects the fingerprint using the light emitted from the organic EL element 220 of the display panel unit 200. Specifically, the light emitted from the organic EL element 220 passes through the components between the organic EL element 220 and the photoelectric conversion element 10 of the fingerprint detection unit 100, and is reflected by the skin (finger surface) of the fingertip of the finger placed in contact with the surface of the display panel unit 200 in the display area 200a. At least a portion of the light reflected by the finger surface passes through the components present therebetween and is received by the photoelectric conversion element 10, and is converted into an electrical signal corresponding to the amount of light received by the photoelectric conversion element 10. Then, the converted electrical signal constitutes image information related to the fingerprint on the finger surface.

The portable information terminal including the display device 2 compares the obtained image information with fingerprint data for fingerprint recognition recorded in advance through any suitable procedure known in the art to perform fingerprint recognition.

(Image detection unit for X-ray imaging device)

FIG. 4 is a diagram schematically showing a configuration example of an image detection unit for an X-ray imaging device.

The image detection unit 1 for an X-ray imaging device includes: a CMOS transistor substrate 20; an interlayer insulating film 30 arranged in a manner covering the CMOS transistor substrate 20; a photoelectric conversion element 10 of an embodiment of the present invention arranged on the interlayer insulating film 30; an interlayer wiring portion 32 arranged in a manner penetrating the interlayer insulating film 30 and electrically connecting the CMOS transistor substrate 20 and the photoelectric conversion element 10; a sealing layer 40 arranged in a manner covering the photoelectric conversion element 10; a scintillator 42 arranged on the sealing layer 40; a reflective layer 44 arranged in a manner covering the scintillator 42; and a protective layer 46 arranged in a manner covering the reflective layer 44.

The CMOS transistor substrate 20 has any suitable configuration known in the art in accordance with the design.

The CMOS transistor substrate 20 includes functional elements such as transistors and capacitors formed within the thickness of the substrate and CMOS transistor circuits (MOS transistor circuits) for realizing various functions.

Examples of the functional element include a floating diffusion element, a reset transistor, an output transistor, and a selection transistor.

A signal readout circuit and the like are fabricated on the CMOS transistor substrate 20 by means of such functional elements, wirings and the like.

The interlayer insulating film 30 may be made of any suitable insulating material known in the past, such as silicon oxide, insulating resin, etc. The interlayer wiring portion 32 may be made of any suitable conductive material (wiring material) known in the past, such as copper, tungsten, etc. The interlayer wiring portion 32 may be, for example, an in-hole wiring formed simultaneously with the formation of the wiring layer, or may be a buried plug formed separately from the wiring layer.

The sealing layer 40 can be made of any suitable material known in the art, provided that it can prevent or suppress the penetration of harmful substances such as oxygen and water that may deteriorate the functionality of the photoelectric conversion element 10. The sealing layer 40 can be made of the same structure as the sealing member 17 described above.

The scintillator 42 can be made of any suitable material known in the art that corresponds to the design of the image detection unit 1 for the X-ray imaging device. Examples of suitable materials for the scintillator 42 include inorganic crystals of inorganic materials such as CsI (cesium iodide), NaI (sodium iodide), ZnS (zinc sulfide), GOS (gadolinium oxysulfide), and GSO (gadolinium silicate); organic crystals of organic materials such as anthracene, naphthalene, and stilbene; organic liquids obtained by dissolving organic materials such as diphenyloxazole (PPO) and terphenyl (TP) in organic solvents such as toluene, xylene, and dioxane; gases such as xenon and helium; plastics, and the like.

The above-mentioned components can be arranged in any appropriate manner corresponding to the design of the photoelectric conversion element 10 and the CMOS transistor substrate 20 , provided that the scintillator 42 can convert incident X-rays into light having a wavelength centered in the visible light region to generate image data.

The reflective layer 44 reflects the light converted by the scintillator 42. The reflective layer 44 can reduce the loss of the converted light and increase the detection sensitivity. In addition, the reflective layer 44 can also block the light directly incident from the outside.

The protective layer 46 can be made of any suitable material known in the art, provided that it can prevent or suppress the penetration of harmful substances such as oxygen and water that may deteriorate the functionality of the scintillator 42 .

Here, the operation of the image detection unit 1 for the X-ray imaging device having the above-mentioned configuration will be briefly described.

When radiation energy such as X-rays and gamma rays enters the scintillator 42 , the scintillator 42 absorbs the radiation energy and converts it into light (fluorescence) having a wavelength in the ultraviolet to infrared region centered on the visible light region. The light converted by the scintillator 42 is then received by the photoelectric conversion element 10 .

In this way, the light received by the photoelectric conversion element 10 via the scintillator 42 is converted into an electrical signal corresponding to the amount of light received by the photoelectric conversion element 10, and is output to the outside of the photoelectric conversion element 10 via the electrode in the form of a light receiving signal, that is, an electrical signal corresponding to the object of imaging. The radiation energy (X-ray) to be detected can be incident from either the scintillator 42 side or the photoelectric conversion element 10 side.

Next, the light-receiving signal output from the photoelectric conversion element 10 is input to the CMOS transistor substrate 20 via the interlayer wiring portion 32, read out by a signal readout circuit manufactured on the CMOS transistor substrate 20, and processed by any other suitable previously known functional portion not shown, thereby generating image information based on the photographed object.

(Vein Detection Section)

5 is a diagram schematically showing an example of the configuration of a vein detection unit for a vein identification device. The vein detection unit 300 for a vein identification device is composed of a cover 306, a light source unit 304, a photoelectric conversion element 10, a support substrate 11, and a glass substrate 302. The cover 306 defines an insertion portion 310 into which a finger (e.g., a fingertip, a finger, or a palm of one or more fingers) as a measurement object is inserted during measurement. The light source unit 304 is provided in the cover 306 to irradiate light to the measurement object. The photoelectric conversion element 10 receives the light irradiated from the light source unit 304 via the measurement object. The support substrate 11 supports the photoelectric conversion element 10. The glass substrate 302 is arranged in a manner opposite to the support substrate 11 with the photoelectric conversion element 10 interposed therebetween, and is separated from the cover 306 by a predetermined distance, and defines the insertion portion 306 together with the cover 306.

In this configuration example, a transmission type imaging method is shown in which the light source unit 304 is integrally configured with the cover unit 306 so as to be separated from the photoelectric conversion element 10 via the measurement object during use. However, the light source unit 304 does not necessarily need to be located on the cover unit 306 side.

On the condition that the light from the light source unit 304 can be effectively irradiated to the measurement object, for example, a reflection type imaging method may be adopted in which the measurement object is irradiated from the photoelectric conversion element 10 side.

The vein detection unit 300 includes the photoelectric conversion element 10 of the embodiment of the present invention as a functional unit that exerts substantial functions. The vein detection unit 300 may include any suitable conventionally known components such as a protection film (not shown), a sealing member, a barrier film, a bandpass filter, a near infrared transmission filter, a visible light cutoff film, and a finger placement guide in a manner corresponding to the design that obtains the desired characteristics. The vein detection unit 300 may also adopt the configuration of the image detection unit 1 that has been described.

The photoelectric conversion element 10 may be included in any manner. For example, a plurality of photoelectric conversion elements 10 may be arranged in a matrix.

As described above, the photoelectric conversion element 10 is provided on the supporting substrate 11 , and the electrodes (first electrodes or second electrodes) are provided on the supporting substrate 11 in a matrix form, for example.

The light received by the photoelectric conversion element 10 is converted into an electrical signal according to the amount of light received by the photoelectric conversion element 10 and is output to the outside of the photoelectric conversion element 10 via the electrodes as a light reception signal, that is, an electrical signal corresponding to the imaged vein.

During vein detection (during use), the object to be measured may or may not be in contact with the glass substrate 302 on the photoelectric conversion element 10 side.

Here, the operation of the vein detection unit 300 will be briefly described.

During vein detection, the vein detection unit 300 detects the vein pattern of the object to be measured using the light emitted from the light source unit 304. Specifically, the light emitted from the light source unit 304 is transmitted through the object to be measured and converted into an electrical signal corresponding to the amount of light received by the photoelectric conversion element 10. Then, the converted electrical signal constitutes image information of the vein pattern of the object to be measured.

In the vein recognition device, vein recognition is performed by comparing the obtained image information with pre-recorded vein data for vein recognition through any conventionally known appropriate procedure.

(Image detection unit for TOF type distance measuring device)

FIG. 6 is a diagram schematically showing a configuration example of an image detection unit for an indirect TOF type distance measuring device.

The image detection unit 400 for a TOF type distance measuring device includes: a CMOS transistor substrate 20; an interlayer insulating film 30 provided in a manner covering the CMOS transistor substrate 20; a photoelectric conversion element 10 of an embodiment of the present invention provided on the interlayer insulating film 30; two floating diffusion layers 402 separately arranged in a manner separating the photoelectric conversion element 10; an insulating layer 401 provided in a manner covering the photoelectric conversion element 10 and the floating diffusion layer 402; and two photogates 404 provided on the insulating layer 401 and separately arranged from each other.

A portion of the insulating layer 401 is exposed from the gap between the two separated photo gates 404 , and the remaining region is shielded from light by the light shielding portion 406 . The CMOS transistor substrate 20 and the floating diffusion layer 402 are electrically connected via an interlayer wiring portion 32 provided to penetrate the interlayer insulating film 30 .

The interlayer insulating film 30 may be made of any suitable insulating material known in the past, such as silicon oxide, insulating resin, etc. The interlayer wiring portion 32 may be made of any suitable conductive material (wiring material) known in the past, such as copper, tungsten, etc. The interlayer wiring portion 32 may be, for example, an in-hole wiring formed simultaneously with the formation of the wiring layer, or may be a buried plug formed separately from the wiring layer.

In this configuration example, the insulating layer 401 can be any suitable configuration known in the art, such as a field oxide film made of silicon oxide.

The photogate 404 may be made of any suitable material known in the art, such as polysilicon.

The image detection unit 400 for a TOF type distance measuring device includes the photoelectric conversion element 10 of an embodiment of the present invention as a functional unit that performs substantial functions. The image detection unit 400 for a TOF type distance measuring device can be provided with any suitable conventionally known components such as a protection film (not shown), a supporting substrate, a sealing substrate, a sealing member, a barrier film, a bandpass filter, and an infrared cut-off film in a manner corresponding to the design to obtain the desired characteristics.

Here, the operation of the TOF distance measuring device image detection unit 400 will be briefly described.

Light is irradiated from a light source, and the light from the light source is reflected by the object to be measured, and the reflected light is received by the photoelectric conversion element 10. Two photogates 404 are provided between the photoelectric conversion element 10 and the floating diffusion layer 402, and by alternately applying pulses, the signal charge generated by the photoelectric conversion element 10 is transferred to one of the two floating diffusion layers 402, so that the charge is accumulated in the floating diffusion layer 402. If the light pulse arrives in an evenly spaced manner relative to the timing of opening the two photogates 404, the amount of charge accumulated in the two floating diffusion layers 402 becomes equal. If the light pulse arrives at one photogate 404 with a delay relative to the timing of the light pulse arriving at the other photogate 404, the amount of charge accumulated in the two floating diffusion layers 402 becomes different.

The difference in the amount of charge accumulated in the floating diffusion layer 402 depends on the delay time of the light pulse. Since the distance L to the measurement object is in the relationship of L = (1/2) ctd using the round-trip time td of light and the speed c of light, if the delay time can be estimated from the difference in the amount of charge in the two floating diffusion layers 402, the distance to the measurement object can be obtained.

The amount of light received by the photoelectric conversion element 10 is converted into an electrical signal as the difference between the amounts of charge accumulated in the two floating diffusion layers 402 , and is output to the outside of the photoelectric conversion element 10 as a light reception signal, that is, an electrical signal corresponding to the measurement target.

Next, the light-receiving signal output from the floating diffusion layer 402 is input to the CMOS transistor substrate 20 via the interlayer wiring portion 32, read out by a signal readout circuit fabricated on the CMOS transistor substrate 20, and processed by any other suitable previously known functional portion not shown, thereby generating distance information based on the measured object.

3. Light detection element

As described above, the photoelectric conversion element of this embodiment can have a light detection function that can convert the irradiated light into an electrical signal corresponding to the amount of light received, and output it to an external circuit via an electrode. Therefore, the photoelectric conversion element of the embodiment of the present invention can be particularly suitable for use as a light detection element with a light detection function. Here, the light detection element of this embodiment can be the photoelectric conversion element itself, or it can also include a functional element for controlling voltage, etc. in addition to the photoelectric conversion element.

4. Method for manufacturing photoelectric conversion element

The method for producing the photoelectric conversion element of this embodiment is not particularly limited. The photoelectric conversion element of this embodiment can be produced by combining formation methods suitable for materials selected when forming the constituent elements.

The method for manufacturing a photoelectric conversion element of the present embodiment may include a step of heating at a heating temperature of 220° C. or higher. More specifically, the active layer is formed by a step of heating at a heating temperature of 220° C. or higher, and/or a step of heating at a heating temperature of 220° C. or higher may be included after the step of forming the active layer.

Hereinafter, as an embodiment of the present invention, a method for manufacturing a photoelectric conversion element having a structure in which a substrate (support substrate), an anode, a hole transport layer, an active layer, an electron transport layer, and a cathode are in contact with each other in this order will be described.

(Step of preparing substrate)

In this process, for example, a support substrate provided with an anode is prepared. Alternatively, a substrate provided with a conductive film formed of the material of the electrode described above can be obtained from the market, and the conductive film can be patterned to form an anode as required, thereby preparing a support substrate provided with an anode.

In the manufacturing method of the photoelectric conversion element of this embodiment, the method for forming the anode when forming the anode on the supporting substrate is not particularly limited. The anode can be formed on the structure to be formed as the anode (e.g., the supporting substrate, the active layer, the hole transport layer) by any suitable method known in the past, such as vacuum evaporation, sputtering, ion plating, plating, and coating.

(Hole Transport Layer Formation Step)

The method for producing a photoelectric conversion element may include a step of forming a hole transport layer (hole injection layer) provided between the active layer and the anode.

The method for forming the hole transport layer is not particularly limited. From the perspective of simplifying the process for forming the hole transport layer, it is preferred to form the hole transport layer by any suitable coating method known in the past. The hole transport layer can be formed, for example, by a coating method using a coating solution containing the material of the hole transport layer already described and a solvent, or by a vacuum evaporation method.

(Active Layer Formation Step)

In the method for manufacturing a photoelectric conversion element of this embodiment, an active layer is formed on the hole transport layer. The active layer as a main component can be formed by any appropriate conventionally known formation process.

In the present embodiment, the active layer is preferably produced by a coating method using an ink composition (coating liquid).

Hereinafter, the step (i) and the step (ii) included in the step of forming the active layer which is the main constituent element of the photoelectric conversion element of the present invention will be described.

Process (i)

As a method for applying the ink composition to the coating object, any appropriate coating method can be used. As the coating method, slit coating, blade coating, spin coating, micro gravure coating, gravure coating, rod coating, inkjet printing, nozzle coating or capillary coating are preferred, slit coating, spin coating, capillary coating or rod coating are more preferred, and slit coating or spin coating are further preferred.

The ink composition used in the method for producing a photoelectric conversion element of the present embodiment includes a composition including a p-type semiconductor material and an n-type semiconductor material, and includes the compound of the present embodiment described above as the n-type semiconductor material, and a solvent.

Here, according to the composition of this embodiment, when selecting a p-type semiconductor material and an n-type semiconductor material, it is preferred to select the n-type semiconductor material in such a way that the band gap (the difference between the energy level of LUMO and the energy level of HOMO) is greater than the band gap of the p-type semiconductor material. If selected in this way, the dark current of the photoelectric conversion element can be more effectively reduced.

The band gap (Eg) of the p-type semiconductor material and the n-type semiconductor material can be measured by any suitable measurement method known in the art. Specifically, the band gap can be calculated by the following formula using the absorption edge wavelength of the compound.

Eg＝hc/absorption end wavelength

In the formula, h represents Planck's constant and c represents the speed of light.

Here, the absorption end wavelength can be determined based on the already described “absorption spectrum.” Specifically, in the obtained absorption spectrum, the wavelength of the intersection of the baseline and the straight line fitted to the long-wavelength side descending curve in the absorption peak curve can be determined as the absorption end wavelength.

The ink composition for forming an active layer according to the present embodiment will be described. It should be noted that the ink composition for forming an active layer according to the present embodiment is an ink composition for forming an active layer having a bulk heterojunction (BHJ) structure.

Therefore, the active layer included in the photoelectric conversion element of this embodiment is a (cured) film formed by curing the ink composition, and is a (cured) film having a bulk heterojunction structure. In other words, the photoelectric conversion element of this embodiment includes a film having a bulk heterojunction structure as an active layer.

The active layer forming ink composition of the present embodiment includes the p-type semiconductor material described above and the compound of the present embodiment described above as an n-type semiconductor material. The active layer forming ink composition of the present embodiment preferably includes the composition and one or more solvents.

According to the active layer forming ink composition of the present embodiment, since it contains the p-type semiconductor material and the “compound of the present embodiment”, it is possible to effectively reduce the dark current required for a photoelectric conversion element, particularly a light detection element.

The ink composition for forming the active layer of the present embodiment is not particularly limited as long as it can form an active layer. As the solvent, for example, a mixed solvent composed of a first solvent and a second solvent described later can be used. Specifically, when the ink composition for forming the active layer contains two or more solvents, it is preferred that the main solvent (first solvent) as the main component and other additional solvents (second solvent) added to improve solubility, etc. can be contained. However, only the first solvent may be used.

Hereinafter, the first solvent and the second solvent that can be suitably used in the active layer forming ink composition of the present embodiment, and a combination thereof will be described.

(1) First solvent

As the first solvent, a solvent capable of dissolving a p-type semiconductor material is preferred. The first solvent of the present embodiment is an aromatic hydrocarbon.

Regarding the aromatic hydrocarbon as the first solvent, for example, toluene, xylene (for example, o-xylene, m-xylene, p-xylene), o-dichlorobenzene, trimethylbenzenes (for example, mesitylene, 1,2,4-trimethylbenzene (pseudocumene)), butylbenzenes (for example, n-butylbenzene, sec-butylbenzene, tert-butylbenzene), methylnaphthalene (for example, 1-methylnaphthalene), tetralin and indane.

The first solvent may be composed of one kind of aromatic hydrocarbon or may be composed of two or more kinds of aromatic hydrocarbons. The first solvent is preferably composed of one kind of aromatic hydrocarbon.

The first solvent is preferably one or more selected from toluene, o-xylene (oXAP), m-xylene, p-xylene, mesitylene, o-dichlorobenzene (ODCB), 1,2,4-trimethylbenzene, n-butylbenzene, sec-butylbenzene, tert-butylbenzene, methylnaphthalene, tetralin and indane, and more preferably toluene, o-xylene, m-xylene, p-xylene, o-dichlorobenzene, mesitylene, 1,2,4-trimethylbenzene, n-butylbenzene, sec-butylbenzene, tert-butylbenzene, methylnaphthalene, tetralin or indane.

(2) Second solvent

The second solvent is a solvent selected from the viewpoint of making the manufacturing process easier to implement and further improving the characteristics of the photoelectric conversion element. Examples of the second solvent include ketone solvents such as acetone, methyl ethyl ketone, cyclohexanone, acetophenone, and propiophenone, and ester solvents such as ethyl acetate, butyl acetate, phenyl acetate, ethyl cellosolve acetate, methyl benzoate (MBZ), butyl benzoate, and benzyl benzoate.

From the viewpoint of further reducing dark current, for example, it is preferable to use acetophenone, propiophenone, methyl benzoate or butyl benzoate as the second solvent.

(3) Combination of the first solvent and the second solvent

Examples of suitable combinations of the first solvent and the second solvent include combinations of o-xylene and methyl benzoate, tetralin and ethyl benzoate, tetralin and propyl benzoate, and tetralin and butyl benzoate.

(4) Weight ratio of the first solvent to the second solvent

From the viewpoint of further improving the solubility of the p-type semiconductor material and the n-type semiconductor material, the weight ratio of the first solvent as the main solvent to the second solvent as the additional solvent (first solvent: second solvent) is preferably set in the range of 85:15 to 99:1.

(5) Any other solvent

The solvent may include any other solvent other than the first solvent and the second solvent. When the total weight of all solvents contained in the ink composition is set to 100% by weight, the content of the other solvent is preferably 5% by weight or less, more preferably 3% by weight or less, and further preferably 1% by weight or less. As the other solvent, a solvent having a higher boiling point than the second solvent is preferred.

(6) Optional ingredients

The ink composition may contain, in addition to the first solvent, the second solvent, the p-type semiconductor material and the n-type semiconductor material, any components such as a surfactant, an ultraviolet absorber, an antioxidant, a sensitizer for sensitizing the function of generating charges using absorbed light, and a light stabilizer for increasing stability against ultraviolet rays, within the limit not impairing the purpose and effect of the present invention.

(7) Concentration of p-type semiconductor materials and n-type semiconductor materials

The concentrations of the p-type semiconductor material and the n-type semiconductor material in the ink composition may be any appropriate concentration within a range that does not impair the purpose of the present invention, taking into account solubility in the solvent and the like.

The weight ratio of the "p-type semiconductor material" to the "n-type semiconductor material" in the ink composition (polymer/non-fullerene compound) is generally in the range of 1/0.1 to 1/10, preferably in the range of 1/0.5 to 1/2, and more preferably 1/1.5.

The total concentration of the "p-type semiconductor material" and the "n-type semiconductor material" in the ink composition is usually 0.01% by weight or more, more preferably 0.02% by weight or more, and even more preferably 0.25% by weight or more. In addition, the total concentration of the "p-type semiconductor material" and the "n-type semiconductor material" in the ink composition is usually 20% by weight or less, preferably 10% by weight or less, and more preferably 7.50% by weight or less.

The concentration of the "p-type semiconductor material" in the ink composition is usually 0.01% by weight or more, more preferably 0.02% by weight or more, and even more preferably 0.10% by weight or more. In addition, the concentration of the "p-type semiconductor material" in the ink composition is usually 10% by weight or less, more preferably 5.00% by weight or less, and even more preferably 3.00% by weight or less.

The concentration of the "n-type semiconductor material" in the ink composition is usually 0.01% by weight or more, more preferably 0.02% by weight or more, and even more preferably 0.15% by weight or more. In addition, the concentration of the "n-type semiconductor material" in the ink composition is usually 10% by weight or less, more preferably 5% by weight or less, and even more preferably 4.50% by weight or less.

(8) Preparation of ink composition

The ink composition can be prepared by a known method. For example, the ink composition can be prepared by a method in which a first solvent or a first solvent and a second solvent are mixed to prepare a mixed solvent, and a p-type semiconductor material and an n-type semiconductor material are added to the obtained mixed solvent; a method in which a p-type semiconductor material is added to the first solvent, an n-type semiconductor material is added to the second solvent, and then the first solvent and the second solvent to which the materials are added are mixed.

The first solvent and the second solvent, the p-type semiconductor material, and the n-type semiconductor material may be heated to a temperature not higher than the boiling point of the solvents and mixed.

The first solvent and the second solvent may be mixed with the p-type semiconductor material and the n-type semiconductor material, and the resulting mixture may be filtered using a filter, and the resulting filtrate may be used as the ink composition. As the filter, for example, a filter made of a fluororesin such as polytetrafluoroethylene (PTFE) may be used.

The ink composition for forming the active layer is applied to a coating object selected according to the photoelectric conversion element and its manufacturing method. The ink composition for forming the active layer can be applied to the functional layer possessed by the photoelectric conversion element, that is, the functional layer in which the active layer may exist, during the manufacturing process of the photoelectric conversion element. Therefore, the coating object of the ink composition for forming the active layer varies according to the layer structure of the manufactured photoelectric conversion element and the order of layer formation. For example, in the case where the photoelectric conversion element has a layer structure in which a substrate, an anode, a hole transport layer, an active layer, an electron transport layer, and a cathode are stacked, and the layer recorded on the left is formed first, the coating object of the ink composition for forming the active layer is the hole transport layer. In addition, for example, in the case where the photoelectric conversion element has a layer structure in which a substrate, a cathode, an electron transport layer, an active layer, a hole transport layer, and an anode are stacked, and the layer recorded on the left is formed first, the coating object of the ink composition for forming the active layer is the electron transport layer.

Step (ii)

As a method for removing the solvent from the coating film of the ink composition, that is, a method for removing the solvent from the coating film and curing it, any appropriate method can be used. Examples of the method for removing the solvent include a method of directly heating using a hot plate in an inert gas atmosphere such as nitrogen, a hot air drying method, an infrared heating drying method, a flash lamp annealing drying method, a reduced pressure drying method, and the like.

The conditions for implementing the step (ii), that is, conditions such as the heating temperature and the heating treatment time, can be any appropriate conditions in consideration of the composition of the ink composition used, the boiling point of the solvent, and the like.

In the present embodiment, specifically, step (ii) can be performed, for example, using a hot plate in a nitrogen atmosphere.

Step (ii) may include multiple heat treatment steps, such as a pre-baking step and a post-baking step. In this case, the heating temperature in the pre-baking step and/or the post-baking step may be any suitable temperature known in the art, that is, about 100°C.

The total heat treatment time in the pre-baking step and the post-baking step can be set to, for example, 1 hour.

The heating temperature in the pre-baking step and the heating temperature in the post-baking step may be the same or different.

The heat treatment time can be set to, for example, 10 minutes or longer. The upper limit of the heat treatment time is not particularly limited, but can be set to, for example, 4 hours in consideration of takt time and the like.

The thickness of the active layer can be set to any appropriate desired thickness by appropriately adjusting the solid content concentration in the coating solution and the conditions of the above-mentioned step (i) and/or step (ii).

The step of forming the active layer may include other steps in addition to the above-mentioned step (i) and step (ii) as long as the object and effect of the present invention are not impaired.

The method for producing a photoelectric conversion element of the present embodiment may be a method for producing a photoelectric conversion element including a plurality of active layers, or may be a method for repeating step (i) and step (ii) a plurality of times.

(Step of Forming Electron Transport Layer)

The method for manufacturing a photoelectric conversion element according to the present embodiment includes a step of forming an electron transport layer (electron injection layer) provided on an active layer.

The method for forming the electron transport layer is not particularly limited. From the viewpoint of simplifying the step of forming the electron transport layer, the electron transport layer is preferably formed by any suitable vacuum deposition method known in the art.

(Cathode Formation Step)

The cathode can be formed by any suitable method known in the art, such as coating, vacuum deposition, sputtering, ion plating, or plating, by forming the electrode material exemplified above on the electron transport layer. The photoelectric conversion element of this embodiment is manufactured by the above steps.

(Sealing Body Forming Step)

When forming the sealed body, in this embodiment, any suitable sealing material (adhesive) and substrate (sealing substrate) known in the past are used. Specifically, after a sealing material such as a UV curable resin is applied to the supporting substrate in a manner surrounding the periphery of the manufactured photoelectric conversion element, the photoelectric conversion element is sealed in the gap between the supporting substrate and the sealing substrate by a method suitable for the selected sealing material such as UV light irradiation, thereby obtaining a sealed body of the photoelectric conversion element.

Example

Hereinafter, examples will be described in order to explain the present invention in more detail. However, the present invention is not limited to the examples described below.

In this example, the polymer compounds shown in Table 1 below were used as p-type semiconductor materials (electron donating compounds), and the compounds shown in Tables 2 and 3 below were used as n-type semiconductor materials (electron accepting compounds).

[Table 1]

(Table 1)

[Table 2](Table 2)

[Table 3]

(Table 3

The polymer compound P-1 as a p-type semiconductor material was synthesized by referring to the method described in International Publication No. 2011/052709 and used.

Compound N-1, Compound N-2, Compound N-3 and Compound N-5, which are n-type semiconductor materials, were synthesized and used as described in the synthesis examples below.

Compound N-4 as an n-type semiconductor material was purchased from the market under the trade name Y6 (manufactured by 1-material Co., Ltd.) and used.

<Synthesis Example 1> (Synthesis of Compound 2)

Compound 2 was synthesized using Compound 1 as described below.

[Chemical formula 82]

Specifically, compound 1 (2.00 g, 3.28 mmol) synthesized by the method described in paragraph [0335] of International Publication No. 2011/052709, dehydrated chloroform (109 mL, 0.02 M) and Vilsmeier reagent ((Chloromethylene)dimethyliminium Chloride)) (0.630 g, 4.92 mmol) were placed in a 300 mL three-necked flask whose internal atmosphere was replaced with nitrogen, and the internal temperature of the three-necked flask was set to 60° C. using an oil bath and maintained for 3 hours.

The three-necked flask was lifted out of the oil bath and cooled to room temperature. Water was poured into the reaction solution in the three-necked flask to rapidly cool it. Then, a saturated aqueous sodium hydrogen carbonate solution was added and stirred at room temperature.

An organic layer was extracted from the obtained reaction solution, washed twice with water, and then dehydrated with magnesium sulfate, and the magnesium sulfate was removed by filtration. The filtrate obtained by filtration was concentrated to the entire amount by a rotary evaporator to obtain a crude product.

The obtained crude product was purified using a silica gel column (the eluent was hexane/ethyl acetate = 100/0 to 98/2 (mass %)) to obtain 2.00 g of Compound 2 (yield 96%) as an orange-black viscous liquid.

The NMR spectrum of the obtained compound 2 was analyzed. The results are as follows.

1H-NMR (400MHz, CHLOROFORM (chloroform)-D) δ9.76-9.72 (1H), 7.24 (1H), 6.70 (1H), 1.88-1.74 (4H), 1.22-1.41 (40H), 0.88-0.83 (6H),

<Synthesis Example 2> (Synthesis of Compound 3)

Compound 3 was synthesized using Compound 2 as described below.

[Chemical formula 83]

Into a 200 mL three-necked flask were placed compound 2 (2.00 g, 4.84 mmol), 9-[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-9H-carbazole (2.14 g, 5.81 mmol) (manufactured by Tokyo Chemical Industry Co., Ltd.) and THF (48 mL, 0.1 M). After the internal atmosphere was replaced with nitrogen, Pd ₂ (dba) ₃ (0.13 g, 0.15 mmol), P(tBu) ₃ HBF ₄ (0.088 g, 0.29 mmol) and 3 M K ₃ PO ₄ aq (48 mL) were sequentially added, and the temperature was raised to 60° C.

After heating and stirring for 2 hours, the reaction solution was cooled to room temperature. The organic layer was extracted from the reaction solution, diluted with hexane, washed with water twice, dried over magnesium sulfate, filtered to remove magnesium nitrate, and the filtrate obtained was concentrated to a total amount using a rotary evaporator to obtain a crude product.

The obtained crude product was purified using a silica gel column (the eluent was hexane/ethyl acetate = 100/0 to 98/2 mass %) to obtain 2.63 g of Compound 3 (yield 67.9%) as an orange viscous liquid.

<Example 1> (Synthesis of Compound 4)

Compound 4 (Compound N-1) was synthesized using Compound 3 and Compound 12 as described below.

[Chemical formula 84]

Into a 50 mL three-necked flask were added compound 3 (0.310 g, 0.387 mmol), dehydrated chloroform (19 g, 0.03 M), compound 12 (0.153 g, 0.581 mmol) synthesized by the method described in Adv. Mater. 2017, 29, 1703080., and pyridine (0.306 g, 3.87 mmol), and the three-necked flask was placed in an oil bath heated to 60°C and maintained.

After heating and stirring for 2 hours, the three-necked flask was lifted from the oil bath and cooled to room temperature. The reaction solution was washed with water once, dehydrated with magnesium sulfate, and the magnesium sulfate was removed by filtering with a Kiriyama funnel. The obtained filtrate was concentrated to the entire amount using a rotary evaporator to obtain a crude product.

The obtained crude product was purified by a silica gel column (eluent: chloroform), and then purified by circulating preparative GPC (eluent: chloroform) to obtain 0.186 g of Compound 4 (yield 46%) as a black solid.

The NMR spectrum of the obtained compound 4 was analyzed. The results are as follows.

1H-NMR (400MHz, CHLOROFORM (chloroform)-D) δ8.72 (1H), 8.71 (1H), 8.13 (2H), 7.84-7.87 (3H), 7.64-7.67 (2H), 7.38-7.46 (5H) ,7.28-7.32(2H),7.10(s,1H),1.89-2.00(4H),1.22-1.50(40H),0.84(6H)

<Example 2> (Synthesis of Compound 5)

Compound 5 (Compound N-2) was synthesized using Compound 3 and Compound 13 as described below.

[Chemical formula 85]

Into a 100 mL three-necked flask were placed compound 3 (0.750 g, 0.937 mmol), compound 13 (0.298 g, 1.22 mmol) synthesized according to the method described in International Publication No. 2020/109823, pTsOH (0.535 g, 2.8 mmol), EtOH (16 mL), toluene (31 mL), and MgSO ₄ (0.38 g), and the three-necked flask was placed in an oil bath heated to 60° C. and maintained.

After heating and stirring for 2 hours, the three-necked flask was cooled to room temperature. The obtained reaction solution was concentrated by an evaporator, toluene was added to the reaction solution, washed with water three times, dried with magnesium sulfate, filtered to remove magnesium sulfate, and the obtained filtrate was concentrated to the total amount by a rotary evaporator to obtain a crude product.

The obtained crude product was purified by a silica gel column (eluent: chloroform), and then purified by circulating preparative GPC (eluent: chloroform) to obtain 0.495 g of Compound 5 (yield 51%) as a black solid.

The NMR spectrum of the obtained compound 5 was analyzed. The results are as follows.

1HNMR (300MHz, CDCl3) δ8.94 (s, 1H), 8.73 (s, 1H), 8.10 (2H), 8.06 (1H), 7.88 (2H), 7.68 (2H), 7.42 (5H), 7.31 (3H) ), 7.14(1H), 1.97(m, 4H), 1.49-1.18(m, 40H), 0.84(6H, -CH3).

<Synthesis Example 4> (Synthesis of Compound 9)

Compound 9 was synthesized using Compound 8 as described below.

[Chemical formula 86]

Compound 8 (1.1 g, 2.2 mmol), TMEDA (0.25 g, 2.2 mmol) synthesized by the method described in paragraph [0271] of International Publication No. 2011/052709, and 16 mL of dehydrated THF were placed in a 100 mL four-necked flask whose internal atmosphere was replaced with nitrogen, and the internal temperature was cooled to -70°C using a bath filled with dry ice and acetone. Next, nBuLi (3.5 mL, 5 mmol) was further added to the four-necked flask and kept for 2 hours.

DMF (0.47 g, 0.6 mmol) was dissolved in 1.8 mL of dehydrated THF and placed in a four-necked flask. The mixture was kept for 1 hour and then heated to room temperature.

Next, a saturated aqueous ammonium chloride solution was further added to the four-necked flask, and the mixture was separated with ethyl acetate to obtain an organic layer. The obtained organic layer was dried over magnesium sulfate, and after filtering out the magnesium sulfate, the obtained filtrate was concentrated using a rotary evaporator to obtain a crude product.

The obtained crude product was purified by a silica gel column (the eluent was hexane/ethyl acetate = 100/2 mass %) to obtain 0.85 g of Compound 9 (yield 78%) as a yellow viscous liquid.

<Synthesis Example 5> (Synthesis of Compound 10)

Compound 10 (Compound N-3) was synthesized using Compound 9 as described below.

[Chemical formula 87]

Into a 100 mL four-necked flask whose internal atmosphere was replaced with nitrogen, compound 9 (0.85 g, 1.44 mmol), dehydrated chloroform (17 g, 20WR), compound 12 (1.14 g, 4.33 mmol) and pyridine (0.05 g, 0.72 mmol) were added, and the four-necked flask was placed in an oil bath heated to 65°C and maintained.

After heating and stirring for 4 hours, cool to room temperature. Pour water into the obtained reaction solution, use a separatory funnel to separate the liquid, collect the organic layer of the lower layer, add water again to separate the liquid, and separate the organic layer. Dehydrate the organic layer with magnesium sulfate, and remove the magnesium sulfate by filtration. The obtained filtrate is concentrated to the entire amount with a rotary evaporator to obtain a crude product.

The obtained crude product was purified by a silica gel column (eluent: chloroform) to obtain 0.37 g of Compound 10 as a brown solid (yield 24%).

<Example 3> (Synthesis of Compound N-5)

Compound 21 was first synthesized as follows.

[Chemical formula 88]

Specifically, 4,4-bis(2-ethylhexyl)-4H-cyclopenta[2,1-b:3,4-b']dithiophene (8.46 g) (manufactured by Tokyo Chemical Industry Co., Ltd.), dehydrated DMF (4.30 g) and dehydrated chloroform (212 mL) were placed in a 500 mL three-necked flask whose internal atmosphere was replaced with nitrogen, and the mixture was cooled to 0°C in an ice bath.

Next, phosphorus oxychloride (3.87 g) was added, and the mixture was heated to room temperature and stirred for 14 hours. After quenching with 20% sodium acetate water, the organic layer was extracted, and the organic layer was washed with water twice, dehydrated with magnesium sulfate, and the magnesium sulfate was removed by filtration. The filtrate obtained by filtration was concentrated to the entire amount using a rotary evaporator, thereby obtaining a crude product.

The obtained crude product was purified using a silica gel column (the eluent was chloroform/hexane = 70/30 (mass %)) to obtain 6.32 g of Compound 21 (yield 70%).

Next, Compound 22 was synthesized using Compound 21 as described below.

[Chemical formula 89]

Specifically, compound 21 (6.31 g, 14.7 mmol) and tetrahydrofuran (THF) (316 mL) were placed in a 1L four-necked flask whose internal atmosphere was replaced with _N2 gas, and the mixture was cooled to an internal temperature of 0°C in an ice bath. N-bromosuccinimide (NBS) (2.66 g, 14.9 mmol) was added, and the mixture was stirred for 14 hours, and water was poured into the reaction solution. Hexane was added to extract the organic layer.

The obtained organic layer was washed twice with water and dehydrated with magnesium sulfate. After removing the magnesium sulfate by filtration, the filtrate was concentrated to a total amount using a rotary evaporator to obtain a crude product.

The obtained crude product was purified using a silica gel column (eluent: hexane/chloroform = 50/50 mass %) to obtain 7.40 g of Compound 22.

Next, Compound 23 was synthesized using Compound 22 as described below.

[Chemical formula 90]

Specifically, compound 12 (2.57 g, 5.04 mmol), 9-[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-9H-carbazole (1.74 g, 6.05 mmol) (manufactured by Tokyo Chemical Industry Co., Ltd.) and THF (72 mL) were placed in a 200 mL three-necked flask, and after replacing the internal atmosphere with nitrogen, K ₂ CO ₃ aq (25 mL) and Pd(PPh ₃ ) ₄ (0.583 g, 0.504 mmol) were added in sequence, and the temperature was raised to 60°C.

After heating and stirring for 2 hours, the reaction solution was cooled to room temperature, 72 mL of ethyl acetate was added, and an organic layer was extracted from the reaction solution. The obtained organic layer was washed with water twice, dried over magnesium sulfate, and filtered to remove magnesium nitrate, and the filtrate thus obtained was concentrated to the entire amount using a rotary evaporator to obtain a crude product.

The obtained crude product was purified by a silica gel column (the eluent was hexane/toluene = 20/80) to obtain 3.14 g of Compound 23 (yield 92.6%).

Next, Compound N-5 was synthesized using Compound 23 as described below.

[Chemical formula 91]

Specifically, compound 23 (0.500 g, 0.744 mmol), compound 13 (0.236 g, 0.97 mmol), pTsOH·H ₂ O (0.425 g, 2.23 mmol), EtOH (12 mL), toluene (25 mL), and MgSO ₄ (0.25 g) were placed in a 100 mL three-necked flask and kept warm in an oil bath heated to 60° C. After stirring for 2 hours, compound 13 (0.093 g, 0.38 mmol) was added and stirred for further 4 hours.

Next, the three-necked flask was taken out of the oil bath, cooled to room temperature, and water was added. EtOH was removed by an evaporator, and methanol was added. The precipitated solid was filtered and recovered using a Kiriyama funnel (containing No. 5B filter paper) to obtain a crude product.

The obtained crude product was recrystallized from chloroform to obtain 0.527 g of compound N-5 (0.587 mmol, yield 79%, LC area percentage value: 98.9%) as a brown solid.

The NMR spectrum of the obtained compound N-5 was analyzed. The results are as follows.

1H-NMR (400MHz, TETRAHYDROFURAN (tetrahydrofuran)-D8) δ 8.97 (1H), 8.95 (1H), 8.39 (1H), 8.12 (2H), 8.02-8.05 (2H), 7.99 (s, 1H), 7.77 (1H), 7.71(2H), 7.45(d, 2H), 7.37(2H), 7.24(2H), 2.05-2.22(m, 4H), 0.98-1.08(m, 16H), 0.72-0.77(m, 6H), 0.63-0.69(m, 6H)

(Band gap of compound (Eg))

Solutions were obtained by dissolving the compounds N-1 to N-5 prepared as described above in o-xylene. Next, the obtained solutions were applied on glass substrates by spin coating to form coating films, which were dried on a hot plate to prepare samples.

The band gap is calculated by the following formula using the absorption edge wavelength of the compound.

Eg＝hc/absorption end wavelength

In the formula, h represents Planck's constant and c represents the speed of light.

It should be noted that the calculation was performed under the assumption that h=6.626×10 ^-34 Js and c=3×10 ⁸ m/s.

It should be noted that the absorption edge wavelength is obtained by the following method.

For a thin film formed from the above sample, an absorption spectrum having absorbance as the vertical axis and wavelength as the horizontal axis was measured.

In the obtained absorption spectrum, the wavelength of the intersection of the base line and the straight line fitted to the descending curve on the long wavelength side of the absorption peak curve was defined as the absorption end wavelength.

The band gaps of polymer compound P-1 and compounds N-1 to N-5 used in this example are shown in Table 4 below.

[Table 4]

(Table 4)

Bandgap(eV) Polymer compound P-1 1.14 Compound 4 (Compound N-1) 1.59 Compound 5 (Compound N-2) 1.49 Compound 10 (Compound N-3) 1.35 Compound N-4 1.34 Compound N-5 1.55

(Absorption peak wavelength)

An absorption spectrum of polymer compound P-1 was obtained by a conventional method. In the obtained absorption spectrum, the value corresponding to the wavelength corresponding to the absorption peak with the maximum absorbance was taken as the "absorption peak wavelength". The absorption peak wavelength of polymer compound P-1 was 921 nm.

The value (eV) of the LUMO energy level of the structural unit contained in the above-mentioned compounds N-1 to N-5 as the n-type semiconductor material in this embodiment is calculated using a computational science method for the compound corresponding to the structural unit.

Specifically, for the compounds (structures) corresponding to each structural unit obtained by cutting the bonds between structural units and adding hydrogen atoms to the bonds generated by the cutting, the quantum chemical calculation program Gaussian03 was applied to perform ground state structural optimization by density functional method at the B3LYP level. For the optimized structure, 6-31g* was used as the basis function for calculation, and the obtained value was used as the value of the LUMO energy level of each structural unit.

The results are shown in the following Tables 5 to 7. In the calculation, a propyl group (—CH ₂ —CH ₂ —CH ₃ ) was used as an example as a representative of the alkyl groups that may be included in the compound (structure).

[Table 5]

(Table 5)

[Table 6]

(Table 6)

[Table 7]

(Table 7)

As described above, the value of the LUMO energy level of ^D1 in compounds N-1 and N-2 (ED _-LUMO ), the value of the LUMO energy level of at least one structural unit among the one or more structural units constituting ^B1 (Eπ _-LUMO ), and the value of the LUMO energy level of ^A1 ( _EA-LUMO ) satisfy the formula “ _ED-LUMO > _EB-LUMO >EA _-LUMO ”.

<Example 4> (Preparation of ink composition I-1)

In a mixed solution of o-xylene (oXAP) and methyl benzoate (MBZ) (95/5 = volume %) as a solvent, a polymer compound P-1 as a p-type semiconductor material was mixed in a concentration of 1.3 mass % relative to the total weight of the ink composition, and a compound N-1 as an n-type semiconductor material was mixed in a concentration of 1.3 mass % relative to the total weight of the ink composition (p-type semiconductor material/n-type semiconductor material = 1/1), stirred at 60° C. for 8 hours, and the obtained mixed solution was filtered using a filter to obtain an ink composition (I-1). The components, etc. are also shown in the following Table 8.

<Example 5> (Preparation of ink composition I-2)

Ink composition (I-2) was prepared in the same manner as in Example 4 except that the n-type semiconductor materials were used in the combination shown in Table 8 below.

<Preparation Example 1> (Preparation of ink composition (I-3))

Ink composition (I-3) was prepared in the same manner as in Example 4 except that the n-type semiconductor materials were used in the combination shown in Table 8 below.

<Preparation Example 2> (Preparation of ink composition (I-4))

Ink composition (I-4) was prepared in the same manner as in Example 4 except that the solvent was ortho-dichlorobenzene (ODCB) and the n-type semiconductor materials were used in the combination shown in Table 8 below.

<Example 6> (Preparation of ink composition I-5)

Ink composition (I-5) was prepared in the same manner as in Example 4 except that the n-type semiconductor materials were used in the combination shown in Table 8 below.

[Table 8]

(Table 8)

Ink composition Solvents p-type semiconductor material n-type semiconductor material Example 4 I-1 oXAP/MBZ P-1 N-1 Example 5 I-2 oXAP/MBZ P-1 N-2 Preparation Example 1 I-3 oXAP/MBZ P-1 N-3 Preparation Example 2 I-4 ODCB P-1 N-4 Example 6 I-5 ODCB P-1 N-5

<Example 7> (Manufacturing and Evaluation of Photoelectric Conversion Element)

(1) Manufacturing of photoelectric conversion elements and sealed bodies thereof

A glass substrate on which a 50 nm thick ITO thin film (anode) was formed by sputtering was prepared, and the glass substrate was subjected to ozone UV treatment as a surface treatment.

Next, the ink composition (I-1) was applied on the ITO thin film by spin coating to form a coating film, which was then dried by heating for 10 minutes using a hot plate heated to 100° C. in a nitrogen atmosphere to form an active layer having a thickness of about 300 nm.

Next, ZnO was applied on the formed active layer by a spin coating method to form an electron transport layer having a thickness of about 50 nm.

Next, a silver (Ag) layer was formed on the formed electron transport layer to a thickness of about 60 nm as a cathode.

Through the above steps, a photoelectric conversion element is manufactured on the glass substrate.

Next, a UV curable sealant as a sealing material is applied to a glass substrate as a supporting substrate in a manner surrounding the periphery of the manufactured photoelectric conversion element, and after bonding the glass substrate as a sealing substrate, UV light is irradiated to seal the light detection element in the gap between the supporting substrate and the sealing substrate, thereby obtaining a sealed body of the photoelectric conversion element. The planar shape of the photoelectric conversion element sealed in the gap between the supporting substrate and the sealing substrate when observed from the thickness direction is a square of 2 mm × 2 mm. The obtained sealed body is referred to as sample 1.

(2) Evaluation of Photoelectric Conversion Element (Evaluation of Dark Current)

In a dark state without irradiation, voltages ranging from -10 V to 2 V were applied to the manufactured sample 1, and the current value when the reverse bias voltage of -2 V was applied was measured by a known method as the value of dark current. The results are shown in Table 9 below.

<Examples 8 and 9 and Comparative Examples 1 and 2> (Manufacturing and Evaluation of Photoelectric Conversion Element)

A sealed body of a photoelectric conversion element was produced and evaluated in the same manner as in Example 7 described above, except that the ink compositions (I-2) to (I-5) were used instead of the ink composition (I-1).

[Table 9]

(Table 9)

Ink composition p-type semiconductor material n-type semiconductor material Dark current value (nA/cm ² ) Example 7 I-1 P-1 N-1 1 Example 8 I-2 P-1 N-2 111 Comparative Example 1 I-3 P-1 N-3 281 Comparative Example 2 1-4 P-1 N-4 33241 Example 9 I-5 P-1 N-5 137

Description of Reference Numerals

1: Image detection unit

2: Display device

10: Photoelectric conversion element

11, 210: Support substrate

12: Anode

13: Hole transport layer

14: Active layer

15: Electron transport layer

16: Cathode

17: Sealing components

20: CMOS transistor substrate

30: Interlayer insulation film

32: Interlayer wiring section

40: Sealing layer

42: Scintillator

44: Reflection layer

46: Protective layer

50: Color Filters

100: Fingerprint detection unit

200: Display panel

200a: Display area

220: Organic EL components

230: Touch sensor panel

240: Sealing substrate

300: Vein detection department

302: Glass substrate

304: Light source

306: Hood

310: Insertion

400: Image detection unit for TOF type distance measuring device

401: Insulation layer

402: Floating diffusion layer

404: Photogate

406: Light shielding part

Claims (13)

1. A composition comprising a p-type semiconductor material and an n-type semiconductor material,

the n-type semiconductor material comprises a compound represented by the following formula (I),

D ¹ -B ¹ -A ¹ (I)

in the formula (I) of the present invention,

D ¹ represents an electron donating group, and is represented by,

A ¹ represents an electron-withdrawing group and is represented by,

B ¹ represents a 2-valent group which comprises 1 or more structural units and constitutes a pi-conjugated system.

2. The composition of claim 1, wherein the n-type semiconductor material has a band gap greater than that of the p-type semiconductor material.

3. The composition according to claim 1 or 2, wherein D ¹ Energy level of LUMO of (E) _D-LUMO Constitution B ¹ Energy level of LUMO of at least 1 structural unit of 1 or more structural units, i.e., E _π-LUMO And A ¹ Energy level of LUMO of (E) _A-LUMO The conditions shown in the following formula are satisfied:

E _D-LUMO ＞E _B-LUMO ＞E _A-LUMO 。

4. the composition of claim 1 or 2, wherein the p-type semiconductor material is a high molecular compound.

5. The composition of claim 4, wherein the p-type semiconductor material is a high molecular compound having an absorption peak wavelength of greater than 700 nm.

6. An ink composition comprising the composition of claim 1 or 2 and a solvent.

7. A film having a bulk heterojunction structure comprising the composition of claim 1 or 2.

8. A photoelectric conversion element comprising the film according to claim 7 as an active layer.

9. The photoelectric conversion element according to claim 8, which is a light detection element.

10. A compound represented by the following formula (I),

D ¹ -B ¹ -A ¹ (I)

in the formula (I) of the present invention,

D ¹ represents an electron donating group, and is represented by,

A ¹ is an electron-withdrawing group and represents an electron-withdrawing group having a ring structure,

B ¹ represents a 2-valent group which comprises 1 or more structural units and constitutes a pi-conjugated system,

the 1 st structural unit which is at least 1 of the 1 st structural units is a structural unit represented by the following formula (II), and the remaining 2 nd structural units other than the 1 st structural unit are a 2-valent group comprising an unsaturated bond, a 2-valent aromatic carbocyclic group or a 2-valent aromatic heterocyclic group,

in the case where there are 2 or more of the 1 st structural units, the 2 or more of the 1 st structural units present are optionally the same or different from each other, in the case where there are 2 or more of the 2 nd structural units, the 2 or more of the 2 nd structural units present are optionally the same or different from each other,

in the formula (II) of the present invention,

Ar ¹ and Ar is a group ² Each independently represents an optionally substituted aromatic carbocyclic ring or an optionally substituted aromatic heterocyclic ring,

y represents a group represented by a direct bond, -C (=O) -, or an oxygen atom,

R each independently represents:

a hydrogen atom,

Halogen atom,

An optionally substituted alkyl group,

Cycloalkyl optionally having substituents,

Aryl optionally having substituents,

Alkoxy optionally having substituent(s),

Optionally substituted cycloalkoxy,

Aryloxy group optionally having a substituent,

Alkylthio optionally having a substituent,

A cycloalkylthio group optionally having a substituent,

Arylthio optionally having a substituent,

A 1-valent heterocyclic group optionally having a substituent,

Substituted amino optionally having substituent(s),

Acyl optionally having substituent(s),

An optionally substituted imine residue,

An amide group optionally having a substituent,

An imide group optionally having a substituent,

Substituted oxycarbonyl optionally having a substituent,

Alkenyl optionally having substituent(s),

Optionally substituted cycloalkenyl,

Alkynyl optionally having substituents,

Optionally substituted cycloalkynyl,

Cyano group,

Nitro group,

-C(＝O)-R ^a A group of the formula

-SO ₂ -R ^b The radicals are shown in the figures,

R ^a and R is ^b Each independently represents:

a hydrogen atom,

An optionally substituted alkyl group,

Aryl optionally having substituents,

Alkoxy optionally having substituent(s),

Aryloxy group optionally having substituent(s), or

A 1-valent heterocyclic group optionally having a substituent,

the plurality of R's present are optionally the same or different from each other.

11. The compound according to claim 10, wherein the 1 st structural unit is a structural unit represented by the following formula (III),

in the formula (III) of the present invention,

y and R are as defined above,

X ¹ and X ² Each independently represents a sulfur atom or an oxygen atom,

Z ¹ and Z ² Each independently represents a group represented by =c (R) -or a nitrogen atom.

12. The compound according to claim 11, wherein the 1 st structural unit is a structural unit represented by the following formula (IV-1),

in the formula (IV-1),

y represents a group represented by-C (=O) -or an oxygen atom,

r each independently represents:

a hydrogen atom,

Halogen atom,

An optionally substituted alkyl group,

Cycloalkyl optionally having substituents,

Aryl optionally having substituents,

Alkoxy optionally having substituent(s),

Optionally substituted cycloalkoxy,

Aryloxy group optionally having a substituent,

Alkylthio optionally having a substituent,

A cycloalkylthio group optionally having a substituent,

Arylthio optionally having a substituent,

A 1-valent heterocyclic group optionally having a substituent,

Substituted amino optionally having substituent(s),

Acyl optionally having substituent(s),

An optionally substituted imine residue,

An amide group optionally having a substituent,

An imide group optionally having a substituent,

Substituted oxycarbonyl optionally having a substituent,

Alkenyl optionally having substituent(s),

Optionally substituted cycloalkenyl,

Alkynyl optionally having substituents,

Optionally substituted cycloalkynyl,

Cyano group,

Nitro group,

-C(＝O)-R ^a A group of the formula

-SO ₂ -R ^b The radicals are shown in the figures,

R ^a and R is ^b Each independently represents:

a hydrogen atom,

An optionally substituted alkyl group,

Aryl optionally having substituents,

Alkoxy optionally having substituent(s),

Aryloxy group optionally having substituent(s), or

A 1-valent heterocyclic group optionally having a substituent,

the plurality of R's present are optionally the same or different from each other.

13. The compound of any one of claims 10-12, wherein B ¹ A 2-valent group having any 1 structure selected from the structures represented by the following formulas (VI-1) to (VI-16),

-CU1-(VI-1)

-CU1-CU1-(VI-2)

-CU1-CU2-(VI-3)

-CU1-CU1-CU1-(VI-4)

-CU1-CU2-CU1-(VI-5)

-CU1-CU1-CU2-(VI-6)

-CU1-CU2-CU2-(VI-7)

-CU2-CU1-CU2-(VI-8)

-CU1-CU1-CU1-CU1-(VI-9)

-CU1-CU1-CU1-CU2-(VI-10)

-CU1-CU1-CU2-CU1-(VI-11)

-CU1-CU1-CU2-CU2-(VI-12)

-CU1-CU2-CU1-CU2-(VI-13)

-CU1-CU2-CU2-CU1-(VI-14)

-CU1-CU2-CU2-CU2-(VI-15)

-CU2-CU1-CU2-CU2-(VI-16)

in the formulas (V-1) to (V-16),

CU1 represents the 1 st structural unit,

CU2 represents the 2 nd building block,

in the case where CU1 exists in 2 or more numbers, the 2 or more numbers of CU1 that exist are optionally the same or different from each other, and in the case where CU2 exists in 2 or more numbers, the 2 or more numbers of CU2 that exist are optionally the same or different from each other, wherein in formula (VI-8), the case where 2 numbers of CU2 that exist are the same is not included.