JP2011082507A - Photoelectric conversion device, production method thereof, photosensor, imaging device and their drive methods - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photoelectric conversion device that functions as a photoelectric conversion device when applied to the photoelectric conversion device, has a small dark current, and can make an amplification width of the dark current small even when the device is subjected to a heat treatment, and to provide an imaging device including such a photoelectric conversion device. <P>SOLUTION: The photoelectric conversion device comprising a transparent electrically conductive film, a photoelectric conversion film and an electrically conductive film in this order, wherein the photoelectric conversion film comprises a photoelectric conversion layer, and an electron blocking layer, wherein the electron blocking layer contains a compound represented by formula (F-3), the compound represented by formula (F-3) having a substituted amino group having three or more ring structures as a substituent. In formula (F-3), R<SB>31</SB>'s each independently represents a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a hydroxyl group, an amino group, or a mercapto group, and they may further have a substituent. R<SB>32</SB>, R<SB>37</SB>, R'<SB>32</SB>, and R'<SB>37</SB>each independently represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a hydroxyl group, an amino group, or a mercapto group, and they may further have a substituent. Here, at least one of R<SB>32</SB>, R<SB>37</SB>, R'<SB>32</SB>, and R'<SB>37</SB>represents a substituted amino group having three or more ring structures. Then m3's each independently represents an integer of 0 to 3. When a plurality of R<SB>31</SB>'s are present in formula (F-3), the plurality of R<SB>31</SB>'s may be different from each other. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

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

As a solid-state imaging device, there is a planar light-receiving device in which photoelectric conversion sites are two-dimensionally arranged in a semiconductor to form pixels, and signals generated by photoelectric conversion in each pixel are transferred and read out by a CCD circuit or a CMOS circuit. Widely used. As a conventional photoelectric conversion site, generally used is a semiconductor in which a photodiode portion using a PN junction is formed in a semiconductor such as Si.
In recent years, as the number of pixels has increased, the pixel size has been reduced, the area of the photodiode portion has been reduced, and the reduction in aperture ratio, the reduction in light collection efficiency, and the resulting sensitivity reduction have become issues. As a technique for improving the aperture ratio and the like, a solid-state imaging device having an organic photoelectric conversion film using an organic material has been proposed.

  In an organic photoelectric conversion film, a technique for introducing a mixed film or a bulk heterostructure using fullerene or a fullerene derivative is known in order to exhibit high photoelectric conversion efficiency (high exciton dissociation efficiency). For example, Patent Document 1 discloses a photoelectric conversion film containing fullerene or a fullerene derivative.

In the organic photoelectric conversion element used in the solar cell, an external electric field is not applied because the purpose is to extract electric power. However, the organic photoelectric conversion element used as a visible light sensor of the solid-state imaging element maximizes the photoelectric conversion efficiency. In order to improve photoelectric conversion efficiency and response speed, an external voltage is applied.
When a voltage is applied from the outside in order to improve the photoelectric conversion efficiency and the response speed, hole injection or electron injection from the electrode is caused by an external electric field, thereby increasing the dark current.

Many materials that are usually used as electrodes in a photoelectric conversion element have a work function (WF) of about 4.5 eV (for example, ITO). For example, fullerene (C ₆₀ ) is used as a material for a photoelectric conversion film. In this case, since the energy gap between the WF of the electrode and the fullerene (C ₆₀ ) LUMO becomes small, electrons are particularly likely to be injected from the electrode into the photoelectric conversion film portion, and the increase in dark current becomes significant.
Regarding prevention of increase in dark current due to injected current, a technique for efficiently preventing injected carriers and reducing dark current by providing a charge blocking layer that suppresses charge injection into the photoelectric conversion layer is disclosed. (Patent Document 2).

  When the photoelectric conversion element is used as a solid-state imaging element, it is necessary to install a color filter through a heating process for colorization, and when the imaging element is soldered to the substrate, the element is heated together with the substrate. Accordingly, it is desired that the photoelectric conversion efficiency decrease and the increase in dark current are small under these process temperatures of 170 ° C. or more for about 30 minutes. However, in Patent Documents 1 and 2, it is practically important. No mention is made of heat resistance which is a major factor, and a compound structure having high heat resistance is not sufficiently described.

Patent Documents 3 to 6 describe organic materials having a fluorene skeleton, and describe the use of the organic materials for electroluminescent elements. An electroluminescent element utilizes light emission that occurs when a voltage is applied to the element. However, a photoelectric conversion element is required to emit substantially no light because its photoelectric conversion efficiency decreases when it emits light. In addition, the electroluminescent element and the photoelectric conversion element have different functions required for materials because the movement directions of holes are opposite and the action is different.
Since the photoelectric conversion element outputs a signal according to the amount of incident light, a constant voltage is applied to the element. As already described, an important function of the electron blocking material in the photoelectric conversion element is suppression of electron injection from the electrode. On the other hand, in an electroluminescent element, since the brightness of light emission is controlled by voltage, such a function is unnecessary.
Patent Document 7 describes an organic material having a fluorene skeleton, and describes the use of the organic material in a dye-sensitized solar cell. However, since the characteristics required for the solar cell are different from those of the photoelectric conversion element intended for the image sensor element, dark current reduction and sufficient heat resistance of the element are not necessary. The description about heat resistance is not fully disclosed.
In addition, when a film is formed using the compound described in Patent Document 7, since the amorphousness is low, grain boundary generation due to crystallization and unevenness may be formed on the film surface, which causes light scattering. It is not suitable as a material for a photoelectric conversion element for the purpose of an optical sensor or an imaging element in which the size of each photoelectric conversion element is in the micron unit.

JP 2007-123707 A JP 2008-72090 A JP 2005-2900000 A Japanese Patent No. 3508984 JP 2007-137795 A JP 2006-131783 A JP 2007-115665 A

In the material for the photoelectric conversion element, in order to realize high photoelectric conversion efficiency and high-speed response, not only the blocking ability against the charge injection from the electrode for reducing the dark current but also generated in the photoelectric conversion film A high charge transport capability that can transport charges to the electrode is also required. In a photoelectric conversion element using a material having a poor charge transporting ability, no photocurrent is observed. Furthermore, in consideration of application to a manufacturing process having a heating process such as color filter installation, protective film installation, element soldering, and improvement in storage stability, the material for the photoelectric conversion element needs to have high heat resistance. .
In other words, in the case of a material for a photoelectric conversion element having a diarylamine partial skeleton utilizing hole transport, the material design should satisfy a small value of Ea (electron affinity), high hole (hole) transportability, and high heat resistance. Although there is a need to do so, the structure is severely limited to meet these requirements.

In addition, it is necessary to consider molecular design so that the position of the energy level becomes a preferable value so that it can be used appropriately in the device configuration.
When a material having a small value of Ip (ionization potential) and a material having a large value of Ea (for example, fullerene C ₆₀ ) are brought into contact, the HOMO of the material layer having a small value of Ip is changed to the LUMO of the material layer having a large value of Ea. Electric charges (electrons and holes) are generated in the photoelectric conversion element due to thermal excitation, and dark current as a noise source increases. The Ip of the electron blocking layer in contact with the fullerene C ₆₀ needs to be sufficiently large and small enough to receive holes without barriers from the HOMO of the material that transports holes in the fullerene C ₆₀ bulk heterolayer. In other words, the Ip of the electron blocking layer has to be designed to have a fairly limited value, and a greater restriction must be imposed on the material design that originally had a small degree of freedom as described above.

The present invention was made to improve the above problems, and when applied to a photoelectric conversion element, functions as a photoelectric conversion element, exhibits a low dark current, and heat-treats the element Another object is to provide a photoelectric conversion element capable of reducing the increase width of the dark current and an imaging element including such a photoelectric conversion element.
Another object of the present invention is to provide a compound that can provide the photoelectric conversion element, and a photoelectric conversion material.

  As a result of intensive studies according to the present invention, it has been found that the above object can be achieved by using a compound having a specific structure. That is, the above problem can be solved by the following means.

[1]
A photoelectric conversion element having a transparent conductive film, a photoelectric conversion film, and a conductive film in this order,
The photoelectric conversion film includes a photoelectric conversion layer and an electron blocking layer,
The electron blocking layer contains a compound represented by the following general formula (F-3),
The photoelectric conversion element whose compound represented by the said general formula (F-3) is a compound which has a substituted amino group containing three or more ring structures as a substituent.
General formula (F-3)

(In General Formula (F-3), each R ₃₁ independently represents a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a hydroxyl group, an amino group, or a mercapto group, and these further have a substituent. R ₃₂ , R ₃₇ , R ′ ₃₂ , and R ′ ₃₇ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a hydroxyl group, an amino group, or a mercapto group. These may further have a substituent, provided that at least one of R ₃₂ , R ′ ₃₂ , R ₃₇ and R ′ ₃₇ represents a substituted amino group containing three or more ring structures. each If .R ₃₁ representing an integer of independently 0-3 is more present in said general formula (F-3), a plurality of R ₃₁ may be different from each other.)
[2]
In the general formula (F-3), R ₃₂ and R ₃₇ represent a substituted amino group containing three or more ring structures, and R ′ ₃₂ and R ′ ₃₇ represent a hydrogen atom. Photoelectric conversion element.
[3]
The photoelectric conversion element according to the above [1] or [2], wherein m3 is 0 in the general formula (F-3).
[4]
The photoelectric conversion element according to the above [1], wherein in the general formula (F-3), R ₃₂ , R ₃₇ , R ′ ₃₂ and R ′ ₃₇ represent a substituted amino group containing three or more ring structures.
[5]
The photoelectric conversion element according to any one of [1] to [4], wherein the substituted amino group containing three or more ring structures is a group represented by the following general formula (A-1).
Formula (A-1)

(In the formula, Ra _{1 to} Ra ₈ each independently represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, or a heterocyclic group, and these may further have a substituent. * Represents a bonding position. Xa represents a single bond, an oxygen atom, a sulfur atom, an alkylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, a divalent heterocyclic group, or an imino group, and these further represent a substituent. May be included.)
[6]
The photoelectric conversion device according to the above [5], wherein Xa in the general formula (A-1) is a single bond, an alkylene group, an alkenylene group, an arylene group, a heterocyclic group, an oxygen atom, a sulfur atom, or an imino group. .
[7]
The photoelectric conversion element according to any one of [1] to [4], wherein the substituted amino group containing three or more ring structures is a group represented by the following general formula (A-2).
General formula (A-2): -N (R _B1 ) (R _B2 )
(R _B1 and R _B2 each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, or a heterocyclic group, and these may further have a substituent, provided that R _B1 and R _B2 At least one represents an aryl group or a heterocyclic group, and the total number of rings contained in R _B1 and R _B2 is 3 or more.)
[8]
The photoelectric conversion element according to the above [7], wherein at least one of R _B1 and R _B2 is a group represented by the following general formula (b-1).
Formula (b-1)

(In the formula, each Rb independently represents a halogen atom, an alkyl group, an aryl group, or a heterocyclic group, and these may further have a substituent. Xb each independently represents a single bond, oxygen, An atom, a sulfur atom, an alkylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, a divalent heterocyclic group, or an imino group, which may further have a substituent, and Rb is plural. When present, they may be the same or different from each other, two Xb's in the formula may be the same or different from each other, * represents a bonding position, m4 represents an integer of 0 to 3, and m5 represents 0 to 0 Represents an integer of 4.)
[9]
A substituted amino group containing three or more ring structures is a group represented by the following general formula (A-3), a group represented by the following general formula (A-4), or the following general formula (A-5). The photoelectric conversion element according to any one of [1] to [4], which is a group represented.

(In the general formulas (A-3) to (A-5), Ra _{33 to} Ra ₃₈ , Ra ₄₁ , Ra _{44 to} Ra ₄₈ , Ra ₅₁ , Ra ₅₂ , Ra _{55 to} Ra ₅₈ are each independently a hydrogen atom. , A halogen atom, or an alkyl group, which may further have a substituent, * represents a bonding position, Xc ₁ , Xc ₂ , and Xc ₃ are each independently a single bond, an oxygen atom, Z ₃₁ represents a sulfur atom, an alkylene group, a silylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, a divalent heterocyclic group, or an imino group, and these may further have a substituent. , Z ₄₁ , and Z ₅₁ each independently represents a cycloalkyl ring, an aromatic hydrocarbon ring, or an aromatic heterocyclic ring, which may further have a substituent.
[10]
The photoelectric conversion element according to any one of [1] to [9], wherein an ionization potential (Ip) of the compound represented by the general formula (F-3) is 5.8 eV or less.
[11]
The photoelectric conversion element according to any one of [1] to [10], wherein an ionization potential (Ip) of the compound represented by the general formula (F-3) is 4.9 eV or more.
[12]
The photoelectric conversion element according to any one of [1] to [11], wherein the compound represented by the general formula (F-3) has a molecular weight of 500 or more and 2000 or less.
[13]
The photoelectric conversion element according to any one of [1] to [12], wherein the photoelectric conversion layer includes an n-type organic semiconductor.
[14]
The photoelectric conversion element according to the above [13], wherein the n-type organic semiconductor is fullerene or a fullerene derivative.
[15]
The photoelectric conversion element according to any one of the above [1] to [14], wherein the photoelectric conversion film contains a compound of the following general formula (I).
Formula (I)

(In the formula, Z ₁ represents an atomic group necessary for forming a 5- or 6-membered ring. L ₁ , L ₂ , and L ₃ each independently represent an unsubstituted methine group or a substituted methine group. D ₁ represents an atomic group, and n1 represents an integer of 0 or more.)
[16]
The photoelectric conversion element according to any one of the above [1] to [15], wherein a conductive film, an electron blocking layer, a photoelectric conversion layer, and a transparent conductive film are laminated in this order.
[17]
It is a manufacturing method of the photoelectric conversion element of any one of said [1]-[15], Comprising: The manufacturing method including the process of forming into a film the said photoelectric converting layer and the said electron blocking layer by vacuum heating vapor deposition, respectively. .
[18]
The optical sensor which consists of a photoelectric conversion element of any one of said [1]-[15].
[19]
The image pick-up element provided with the photoelectric conversion element of any one of said [1]-[15].
[20]
The photoelectric conversion element according to any one of [1] to [15], the optical sensor according to [18], or the image sensor driving method according to [19], wherein the electronic blocking is performed. A driving method in which a voltage greater than 0 V and not greater than 100 V is applied with the electrode in contact with the layer as the cathode and the other electrode as the anode.
[21]
The electron blocking material which consists of a compound represented by general formula (F-3) as described in said [1].
[22]
A film having a thickness of 1 to 1000 nm containing the compound represented by the general formula (F-3) described in [1] above.

  According to the present invention, when a compound having a specific structure is applied to a photoelectric conversion element, it functions as a photoelectric conversion element, the element exhibits a low dark current, and even when the element is heated, It is possible to provide a photoelectric conversion element capable of reducing the increase width and an imaging element including such a photoelectric conversion element.

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

[Photoelectric conversion element]
The photoelectric conversion element of the present invention is a photoelectric conversion element having a transparent conductive film, a photoelectric conversion film, and a conductive film in this order,
The photoelectric conversion film includes a photoelectric conversion layer and an electron blocking layer,
The electron blocking layer contains a compound represented by the following general formula (F-3),
The compound represented by the general formula (F-3) is a compound having a substituted amino group containing three or more ring structures as a substituent.
Formula (F-3)

(In General Formula (F-3), each R ₃₁ independently represents a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a hydroxyl group, an amino group, or a mercapto group, and these further have a substituent. R ₃₂ , R ₃₇ , R ′ ₃₂ , and R ′ ₃₇ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a hydroxyl group, an amino group, or a mercapto group. These may further have a substituent, provided that at least one of R ₃₂ , R ′ ₃₂ , R ₃₇ and R ′ ₃₇ represents a substituted amino group containing three or more ring structures. each If .R ₃₁ representing an integer of independently 0-3 is more present in said general formula (F-3), a plurality of R ₃₁ may be different from each other.)

Moreover, this invention relates also to the electron blocking material which consists of a compound represented by general formula (F-3).
The present invention also relates to a film having a thickness of 1 to 1000 nm containing a compound represented by the general formula (F-3).

Hereinafter, preferred embodiments of the photoelectric conversion element according to the present invention will be described.
The photoelectric conversion element according to the present invention may be formed by laminating a conductive film, a photoelectric conversion layer, an electron blocking layer, and a transparent conductive film in this order. Preferred embodiments include a conductive film, an electron blocking layer, A photoelectric conversion layer and a transparent conductive film are laminated in this order.

In FIG. 1, the structural example of the photoelectric conversion element of this invention is shown.
A photoelectric conversion element 10a shown in FIG. 1A includes an electron blocking layer 16A formed on a lower electrode 11 on an electroconductive film (hereinafter referred to as a lower electrode) 11 functioning as a lower electrode, and an electron blocking layer. A photoelectric conversion layer 12 formed on 16A and a transparent conductive film (hereinafter referred to as an upper electrode) 15 functioning as an upper electrode are stacked in this order.
FIG. 1B shows a configuration example of another photoelectric conversion element. The photoelectric conversion element 10b shown in FIG. 1B has a configuration in which an electron blocking layer 16A, a photoelectric conversion layer 12, a hole blocking layer 16B, and an upper electrode 15 are stacked in this order on a lower electrode 11. . Note that the stacking order of the electron blocking layer, the photoelectric conversion layer, and the hole blocking layer in FIGS. 1A and 1B may be reversed depending on the application and characteristics.
The elements constituting the photoelectric conversion element according to this embodiment will be described.

(electrode)
The electrodes (upper electrode (transparent conductive film) 15 and lower electrode (conductive film) 11) are made of a conductive material. As the conductive material, a metal, an alloy, a metal oxide, an electrically conductive compound, or a mixture thereof can be used.
Since light is incident from the upper electrode 15, the upper electrode 15 needs to be sufficiently transparent to the light to be detected. Specifically, conductive metal oxides such as tin oxide (ATO, FTO) doped with antimony or fluorine, tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO), Metal thin films such as gold, silver, chromium and nickel, and mixtures or laminates of these metals and conductive metal oxides, inorganic conductive materials such as copper iodide and copper sulfide, organic materials such as polyaniline, polythiophene and polypyrrole Examples thereof include conductive materials and laminates of these with ITO. Among these, conductive metal oxides are preferable from the viewpoint of high conductivity and transparency. Since the upper electrode 15 is formed on the organic photoelectric conversion layer 12, it is preferably formed by a method that does not deteriorate the characteristics of the organic photoelectric conversion layer 12.

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

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

  The upper electrode 15 is preferably made plasma-free. By creating the upper electrode 15 in a plasma-free manner, the influence of plasma on the substrate can be reduced, and the photoelectric conversion characteristics can be improved. Here, plasma free means that no plasma is generated during the deposition of the upper electrode 15 or that the distance from the plasma generation source to the substrate is 2 cm or more, preferably 10 cm or more, more preferably 20 cm or more. It means a state in which the plasma that reaches is reduced.

  Examples of an apparatus that does not generate plasma during the formation of the upper electrode 15 include an electron beam vapor deposition apparatus (EB vapor deposition apparatus) and a pulse laser vapor deposition apparatus. Regarding EB deposition equipment or pulse laser deposition equipment, “Surveillance of Transparent Conductive Films” supervised by Yutaka Sawada (published by CMC, 1999), “New Development of Transparent Conductive Films II” supervised by Yutaka Sawada (published by CMC, 2002) ), "Transparent conductive film technology" by the Japan Society for the Promotion of Science (Ohm Co., 1999), and the references attached thereto, etc. can be used. Hereinafter, a method of forming a transparent electrode film using an EB vapor deposition apparatus is referred to as an EB vapor deposition method, and a method of forming a transparent electrode film using a pulse laser vapor deposition apparatus is referred to as a pulse laser vapor deposition method.

  For an apparatus that can realize a state in which the distance from the plasma generation source to the substrate is 2 cm or more and the arrival of plasma to the substrate is reduced (hereinafter referred to as a plasma-free film forming apparatus), for example, an opposed target sputtering Equipment, arc plasma deposition, etc. are considered, and these are supervised by Yutaka Sawada "New development of transparent conductive film" (published by CMC, 1999), and supervised by Yutaka Sawada "New development of transparent conductive film II" (published by CMC) 2002), “Transparent conductive film technology” (Ohm Co., 1999) by the Japan Society for the Promotion of Science, and references and the like attached thereto can be used.

  When a transparent conductive film such as TCO is used as the upper electrode 15, a DC short circuit or an increase in leakage current may occur. One reason for this is thought to be that fine cracks introduced into the photoelectric conversion layer 12 are covered by a dense film such as TCO, and conduction between the first electrode film 11 on the opposite side is increased. For this reason, in the case of an electrode having a poor film quality such as Al, an increase in leakage current hardly occurs. By controlling the film thickness of the upper electrode 15 with respect to the film thickness of the photoelectric conversion layer 12 (that is, the depth of cracks), an increase in leakage current can be largely suppressed. It is desirable that the thickness of the upper electrode 15 is 1/5 or less, preferably 1/10 or less of the thickness of the photoelectric conversion layer 12.

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

(Electron blocking layer, hole blocking layer)
The electron blocking layer in the photoelectric conversion element of the present invention contains a compound represented by the following general formula (F-3). The compound contained in the electron blocking layer (hereinafter also referred to as the compound according to the present invention) is a compound having a substituted amino group containing three or more ring structures as a substituent.
Furthermore, the compound in the present invention may have a substituent, but since the substituent is preferably suitable for vacuum heating deposition, it is preferably not a polymerizable group that reacts with heat. The polymerizable group is a substituent including a non-aromatic double bond and a substituent including an alicyclic ether structure in which any terminal is unsubstituted (structure of CH ₂ ═C), specifically Examples thereof include a substituent having a styryl group, an acrylate group, a methacrylate group, an acrylamide group, a methacrylamide group, an epoxy group, or an oxetane group as a partial structure.
Formula (F-3)

(In General Formula (F-3), each R ₃₁ independently represents a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a hydroxyl group, an amino group, or a mercapto group, and these further have a substituent. R ₃₂ , R ₃₇ , R ′ ₃₂ , and R ′ ₃₇ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a hydroxyl group, an amino group, or a mercapto group. These may further have a substituent, provided that at least one of R ₃₂ , R ′ ₃₂ , R ₃₇ and R ′ ₃₇ represents a substituted amino group containing three or more ring structures. each If .R ₃₁ representing an integer of independently 0-3 is more present in said general formula (F-3), a plurality of R ₃₁ may be different from each other.)

When R ₃₂ , R ₃₇ , R ′ ₃₂ , and R ′ ₃₇ are not a substituted amino group containing three or more ring structures, each independently represents a hydrogen atom, a halogen atom (preferably a fluorine atom, a chlorine atom, a bromine atom, Or an iodine atom), an alkyl group, an aryl group, a heterocyclic group, a hydroxyl group, an amino group, or a mercapto group, and a substituent having a low polarity is advantageous for transporting holes, so that a hydrogen atom, an alkyl A hydrogen atom is particularly preferable because a group or an aryl group is preferable, and a simple structure is advantageous in terms of material cost.
When R ₃₂ , R ₃₇ , R ′ ₃₂ , and R ′ ₃₇ are not a substituted amino group containing three or more ring structures, R ₃₂ , R ₃₇ , R ′ ₃₂ , and R ′ ₃₇ have 0 to 18 carbon atoms. Is preferable, 0 to 10 is more preferable, and 0 to 6 is still more preferable.
When R ₃₂ , R ₃₇ , R ′ ₃₂ , and R ′ ₃₇ represent an alkyl group, the alkyl group is preferably an alkyl group having 1 to 18 carbon atoms, more preferably an alkyl group having 1 to 12 carbon atoms, An alkyl group having 1 to 10 carbon atoms is more preferable, and an alkyl group having 1 to 6 carbon atoms is particularly preferable. Specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, or a cyclohexyl group is preferable.
When R ₃₂ , R ₃₇ , R ′ ₃₂ , and R ′ ₃₇ represent an aryl group, the aryl group is preferably an aryl group having 6 to 18 carbon atoms, more preferably an aryl group having 6 to 14 carbon atoms, An aryl group having 6 to 10 carbon atoms is more preferable. Specifically, a phenyl group, a naphthyl group, or an anthryl group is preferable, and a phenyl group or a naphthyl group is more preferable.
When R ₃₂ , R ₃₇ , R ′ ₃₂ and R ′ ₃₇ represent a heterocyclic group, the heterocyclic group is preferably a C 4-16 heterocyclic group, and a C 4-10 heterocyclic group. Is more preferable. Specifically, a pyridyl group, a pyrimidyl group, a furanyl group, or a thienyl group is preferable.
When R ₃₂ , R ₃₇ , R ′ ₃₂ , and R ′ ₃₇ represent an alkyl group, an aryl group, a heterocyclic group, a hydroxyl group, an amino group, or a mercapto group, these may further have a substituent. Specific examples of the further substituent include the substituent W described later.

Each R ₃₁ is preferably a halogen atom (preferably a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom), an alkyl group, a heterocyclic group, a hydroxyl group, an amino group, or a mercapto group. A hydrogen atom, an alkyl group, or a heterocyclic group is more preferable because it is advantageous for transporting holes, and a hydrogen atom or an alkyl group is more preferable. If an alkyl group, there is no reactive proton, Alkyl groups are particularly preferred because high durability can be estimated.
The number of carbon atoms in R ₃₁ is preferably 0 to 18, more preferably 0-10, more preferably 0-6.
When R ₃₁ represents an alkyl group, the alkyl group is preferably an alkyl group having 1 to 18 carbon atoms, more preferably an alkyl group having 1 to 12 carbon atoms, and more preferably an alkyl group having 1 to 6 carbon atoms. Specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, or a cyclohexyl group is preferable.
When R ₃₁ represents an aryl group, the aryl group is preferably an aryl group having 6 to 18 carbon atoms, and more preferably an aryl group having 6 to 10 carbon atoms. Specifically, a phenyl group, a naphthyl group, or an anthryl group is preferable.
When R ₃₁ represents a heterocyclic group, the heterocyclic group is preferably a C 4-16 heterocyclic group, and more preferably a C 4-10 heterocyclic group. Specifically, a pyridyl group, a pyrimidyl group, a furanyl group, a furfuryl group, or a thienyl group is preferable.
When R ₃₁ represents an alkyl group, an aryl group, a heterocyclic group, a hydroxyl group, an amino group, or a mercapto group, these may further have a substituent. Specific examples of the further substituent include the substituent W described later.

  m3 represents any integer of 0 to 3, and 0 to 2 is preferable and 0 is particularly preferable because a simple structure is advantageous in terms of cost.

Further, if possible, adjacent ones of R ₃₁ may be bonded to each other to form a ring. Examples of the ring include ring R described later.

In the general formula (F-3), at least any two of R ₃₂ , R ₃₇ , R ′ ₃₂ and R ′ ₃₇ have a ring structure because the high heat resistance of the device which is the subject of the present invention can be obtained. It is preferably a substituted amino group containing two or more, and particularly preferably R ₃₂ , R ₃₇ , R ′ ₃₂ and R ′ ₃₇ are substituted amino groups containing three or more ring structures.
Further, for the reason that it is possible to reduce the dark current, R _32, and R ₃₇ represents a substituted amino group containing three or more ring structures, R _'32 and R' ₃₇ is preferably represents a hydrogen atom.

In General Formula (F-3), a substituted amino group containing three or more ring structures can be bonded to the fluorene skeleton directly or via another group.
The other group is preferably an oxygen atom, a sulfur atom, an alkylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, a divalent heterocyclic group, or an imino group (—NH—). The alkylene group, alkenylene group, cycloalkylene group, cycloalkenylene group, arylene group, divalent heterocyclic group, or imino group may further have a substituent. Specific examples of the further substituent include the substituent W described later. More preferably, the other group is preferably an alkylene group having 1 to 12 carbon atoms, an alkenylene group having 2 to 12 carbon atoms, an arylene group having 6 to 14 carbon atoms, a heterocyclic group having 4 to 13 carbon atoms, an oxygen atom, sulfur. An imino group (for example, phenylimino group, methylimino group, t-butylimino group) having an atom or a hydrocarbon group having 1 to 12 carbon atoms (preferably an aryl group or an alkyl group), more preferably an alkylene having 1 to 6 carbon atoms Group (for example, methylene group, 1,2-ethylene group, 1,1-dimethylmethylene group), alkenylene group having 2 carbon atoms (for example, —CH ₂ ═CH ₂ —), arylene group having 6 to 10 carbon atoms (for example, 1 , 2-phenylene group, 2,3-naphthylene group).

  Since a simple structure is advantageous in terms of material cost, a substituted amino group containing three or more ring structures is preferably directly bonded rather than bonded to a fluorene skeleton via another group.

The substituted amino group containing 3 or more ring structures is preferably a substituted amino group containing 3 or more rings in total. Here, when a substituted amino group containing three or more ring structures contains a condensed ring, each cyclic component of the monocyclic ring constituting the condensed ring is counted as one ring.
In a substituted amino group containing three or more ring structures, it is more preferable that the total number of rings is 3 to 6, and more preferably 4 to 5. The number of carbon atoms of the substituted amino group containing three or more ring structures is preferably 5 to 40 carbon atoms, and more preferably 10 to 30 carbon atoms.

The substituted amino group containing three or more ring structures is preferably an amino group having as a substituent a group having a structure in which three or more rings are formed by the condensation of two aromatic hydrocarbons. Moreover, the form by which the nitrogen atom of a substituted amino group is contained in a part of ring structure may be sufficient. Specific examples include a carbazole structure, an acridan structure, a dibenzoazepine structure, and a benzo-fused ring derivative structure thereof.
The two aromatic hydrocarbons are preferably composed of a 6-membered ring. In addition, the aromatic hydrocarbon itself may be a condensed ring (such as naphthalene).

Specific examples of the substituted amino group containing three or more ring structures include substituted amino groups having the following examples A5 to A7 as substituents. Moreover, the form in which the nitrogen atom of a substituted amino group is contained in a part of ring structure like the group shown to the below-mentioned illustrations N1-N13 may be sufficient.
The compound represented by the general formula (F-3) according to the present invention includes a substituted amino group containing three or more of such ring structures, and thus has a low thermal excitation current generation capability unique to this structure. The change in the molecular state during heating is small, and the change in intermolecular interaction between the compound represented by the general formula (F-3) and the compound used in the photoelectric conversion layer is small. This is considered to contribute to the reduction and suppression of dark current increase due to heating.
Although the substituted position of the substituted amino group containing 3 or more ring structures is not particularly limited, it is preferable to have at least one of R ₂ and R ₇ described above.

In the general formula (F-3), the substituted amino group containing three or more ring structures is more specifically a group represented by the following general formula (A-1), a general formula (A-2) ), A group represented by the following general formula (A-3), a group represented by the following general formula (A-4), or a group represented by the following general formula (A-5). Can be mentioned.
Formula (A-1)

(In the formula, Ra _{1 to} Ra ₈ each independently represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, or a heterocyclic group, and these may further have a substituent. * Represents a bonding position. Xa represents a single bond, an oxygen atom, a sulfur atom, an alkylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, a divalent heterocyclic group, or an imino group, and these further represent a substituent. May be included.)

In the general formula (A-1), Ra _{1 to} Ra ₈ are each independently a hydrogen atom, a halogen atom (preferably a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom), an alkyl group, an aryl group, or a complex. Represents a cyclic group. Ra ₁ to Ra ₈ are preferably a hydrogen atom, an alkyl group, or an aryl group, preferably a hydrogen atom or an alkyl group, because a substituent having a low polarity is advantageous for transporting holes. Is more preferable, and a hydrogen atom is still more preferable.
When Ra _{1 to} Ra ₈ represent an alkyl group, the alkyl group is preferably an alkyl group having 1 to 18 carbon atoms, more preferably an alkyl group having 1 to 12 carbon atoms, and an alkyl group having 1 to 6 carbon atoms. Further preferred. The alkyl group may be linear, branched or cyclic. Specifically, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a t-butyl group, a hexyl group, or a cyclohexyl group is preferable, and a methyl group, an ethyl group, an isopropyl group, or an n-butyl group is preferable. Group, t-butyl group is more preferable, and methyl group, ethyl group or t-butyl group is still more preferable.
When Ra _{1 to} Ra ₈ represent an aryl group, the aryl group is preferably an aryl group having 6 to 18 carbon atoms, more preferably an aryl group having 6 to 14 carbon atoms, and an aryl group having 6 to 10 carbon atoms. Further preferred. Specifically, a phenyl group or a naphthyl group is preferable.
When Ra _{1 to} Ra ₈ represent a heterocyclic group, the heterocyclic group is preferably a C 4-16 heterocyclic group, and more preferably a C 4-10 heterocyclic group. Specifically, a pyridyl group, a pyrimidyl group, a furanyl group, or a thienyl group is preferable.

When Ra _{1 to} Ra ₈ represent an alkyl group, an aryl group, or a heterocyclic group, these may further have a substituent. Examples of the further substituent include the substituent W described later.
Adjacent ones of Ra _{1 to} Ra ₈ may be bonded to each other to form a ring. Examples of the ring include ring R described later. The ring is preferably a benzene ring, naphthalene ring, anthracene ring, pyridine ring, pyrimidine ring or the like.

  In General Formula (A-1), Xa represents a moiety that forms a condensed ring, and is a single bond, an oxygen atom, a sulfur atom, an alkylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, or a divalent complex. Represents a cyclic group or an imino group. When Xa represents an alkylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, a divalent heterocyclic group, or an imino group, these may further have a substituent. Examples of the further substituent include the substituent W described later.

Xa is a single bond, an alkylene group having 1 to 12 carbon atoms, an alkenylene group having 2 to 12 carbon atoms, an arylene group having 6 to 14 carbon atoms, a heterocyclic group having 4 to 13 carbon atoms, an oxygen atom, a sulfur atom, carbon An imino group (for example, phenylimino group, methylimino group, t-butylimino group) having a hydrocarbon group (preferably an aryl group or an alkyl group) having 1 to 12 carbon atoms is preferable, and a single bond or an alkylene group having 1 to 6 carbon atoms ( for example, methylene group, 1,2-ethylene group, 1,1-dimethylmethylene group), an alkenylene group having 2 carbon atoms (e.g., _-CH 2 = _CH 2 -), an arylene group having 6 to 10 carbon atoms (e.g., 1, 2 -Phenylene group and 2,3-naphthylene group) are more preferable, and a single bond, an alkylene group having 1 to 6 carbon atoms, or an arylene group having 6 to 10 carbon atoms is particularly preferable.

  In the general formula (F-3), examples of the substituted amino group containing three or more ring structures also include a group represented by the following general formula (A-2).

Formula (A-2): -N (R _B1 ) (R _B2 )
(R _B1 and R _B2 each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, or a heterocyclic group, provided that at least one of R _B1 and R _B2 represents an aryl group or a heterocyclic group. And the total number of rings contained in R _B1 and R _B2 is 3 or more.)

In general formula (A-2), R _B1 and R _B2 are preferably an alkyl group, an aryl group, or a heterocyclic group, more preferably an aryl group or a heterocyclic group, and excellent hole transport ability. Aryl groups are more preferred.
When R _B1 and R _B2 represent an alkyl group, the alkyl group is preferably an alkyl group having 1 to 18 carbon atoms, and more preferably an alkyl group having 1 to 12 carbon atoms. Specifically, a methyl group, an ethyl group, a propyl group, or a butyl group is preferable.
When R _B1 and R _B2 represent an aryl group, the aryl group is preferably an aryl group having 6 to 18 carbon atoms, and more preferably an aryl group having 6 to 14 carbon atoms. Specifically, a phenyl group, a naphthyl group, a fluorenyl group, a biphenyl group (as more specific examples thereof, A1 to A11 described later), an anthryl group, or a pyrenyl group are preferable, and a phenyl group, a naphthyl group, A fluorenyl group or a biphenyl group is more preferred, and a naphthyl group is still more preferred.
When R _B1 and R _B2 represent a heterocyclic group, the heterocyclic group is preferably a heterocyclic group having 4 to 16 carbon atoms, and more preferably a heterocyclic group having 4 to 10 carbon atoms. Specifically, a carbazolyl group, an indolyl group, or an imidazolyl group is preferable.
When R _B1 and R _B2 represent an alkyl group, an aryl group, or a heterocyclic group, these may further have a substituent. Specific examples of the further substituent include the substituent W described later.

Preferably, an embodiment in which at least one of R _B1 and R _B2 is a group represented by the following general formula (b-1) is also preferable. More preferably, both R _B1 and R _B2 are groups represented by the following general formula (b-1).
Formula (b-1)

(In the formula, each Rb independently represents a halogen atom, an alkyl group, an aryl group, or a heterocyclic group, and these may further have a substituent. Xb each independently represents a single bond, oxygen, An atom, a sulfur atom, an alkylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, a divalent heterocyclic group, or an imino group, which may further have a substituent, and Rb is plural. When present, they may be the same or different from each other, two Xb's in the formula may be the same or different from each other, * represents a bonding position, m4 represents an integer of 0 to 3, and m5 represents 0 to 0 Represents an integer of 4.)

When Rb represents an alkyl group, an aryl group, or a heterocyclic group, these may further have a substituent. Specific examples of the further substituent include the substituent W described later.
Adjacent ones of a plurality of Rb may be bonded to each other to form a ring. Examples of the ring include a ring R described later, preferably a benzene ring or a naphthalene ring.

Rb is preferably a halogen atom, an alkyl group having 1 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, or a heterocyclic group having 4 to 16 carbon atoms, an alkyl group having 1 to 12 carbon atoms, or 6 to 14 carbon atoms. Are more preferable, an alkyl group having 1 to 6 carbon atoms and an aryl group having 6 to 10 carbon atoms are more preferable, and an alkyl group having 1 to 6 carbon atoms is particularly preferable.
It is also preferable that m4 is 0 and m5 is 0.

Xb represents a single bond, an oxygen atom, a sulfur atom, an alkylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, a divalent heterocyclic group, or an imino group. Xb is a single bond, an alkylene group having 1 to 12 carbon atoms, an alkenylene group having 2 to 12 carbon atoms (for example, —CH ₂ ═CH ₂ —), an arylene group having 6 to 14 carbon atoms (for example, 1,2-phenylene group). , 2,3-naphthylene group), a heterocyclic group having 4 to 13 carbon atoms, an oxygen atom, a sulfur atom, an hydrocarbon group having 1 to 12 carbon atoms (preferably an aryl group or an alkyl group) (for example, phenyl) An imino group, a methylimino group, a t-butylimino group), a single bond, an alkylene group having 1 to 6 carbon atoms (for example, a methylene group, a 1,2-ethylene group, a 1,1-dimethylmethylene group), an oxygen atom, sulfur More preferred are atoms and imino groups having 1 to 6 carbon atoms.
When Xb represents an alkylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, a divalent heterocyclic group, or an imino group, these may further have a substituent. Examples of the further substituent include the substituent W described later.

  Specific examples of the group represented by the general formula (b-1) are shown below, but are not limited thereto.

  In the general formula (F-3), examples of the substituted amino group containing three or more ring structures include a group represented by the following general formula (A-3) and a group represented by the following general formula (A-4). Or a group represented by the following general formula (A-5).

(In the general formulas (A-3) to (A-5), Ra _{33 to} Ra ₃₈ , Ra ₄₁ , Ra _{44 to} Ra ₄₈ , Ra ₅₁ , Ra ₅₂ , Ra _{55 to} Ra ₅₈ are each independently a hydrogen atom. , A halogen atom, or an alkyl group, which may further have a substituent, * represents a bonding position, Xc ₁ , Xc ₂ , and Xc ₃ are each independently a single bond, an oxygen atom, Z ₃₁ represents a sulfur atom, an alkylene group, a silylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, a divalent heterocyclic group, or an imino group, and these may further have a substituent. , Z ₄₁ , and Z ₅₁ each independently represents a cycloalkyl ring, an aromatic hydrocarbon ring, or an aromatic heterocyclic ring, which may further have a substituent.

In the general formulas (A-3) to (A-5), Ra _{33 to} Ra ₃₈ , Ra ₄₁ , Ra _{44 to} Ra ₄₈ , Ra ₅₁ , Ra ₅₂ , Ra _{55 to} Ra ₅₈ are each independently a hydrogen atom, A halogen atom (preferably a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom) or an alkyl group is represented. A hydrogen atom or an alkyl group is preferable because a substituent having a low polarity is advantageous for transporting holes.
When Ra _{33 to} Ra ₃₈ , Ra ₄₁ , Ra _{44 to} Ra ₄₈ , Ra ₅₁ , Ra ₅₂ , Ra _{55 to} Ra ₅₈ represent an alkyl group, the alkyl group is preferably an alkyl group having 1 to 18 carbon atoms, A C1-C12 alkyl group is more preferable, and a C1-C6 alkyl group is still more preferable. Specifically, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, or a cyclohexyl group is preferable.
In the general formulas (A-3) to (A-5), adjacent ones of Ra _{33 to} Ra ₃₈ , Ra ₄₁ , Ra _{44 to} Ra ₄₈ , Ra ₅₁ , Ra ₅₂ , Ra _{55 to} Ra ₅₈ are bonded to each other. To form a ring. Examples of the ring include ring R described later. The ring is preferably a benzene ring, a naphthalene ring, an anthracene ring, a pyridine ring, a pyrimidine ring or the like, and a benzene ring is more preferable.

Xc ₁ , Xc ₂ , and Xc ₃ are each independently a single bond, an oxygen atom, a sulfur atom, an alkylene group, a silylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, or a divalent heterocyclic group. Or an imino group. When Xc ₁ , Xc ₂ , and Xc ₃ represent an alkylene group, a silylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, a divalent heterocyclic group, or an imino group, these are further substituted. You may have. Examples of the further substituent include the substituent W described later.

Xc _1, Xc _2, and Xc ₃ is a single bond, an alkylene group having 1 to 12 carbon atoms, an alkenylene group having 2 to 12 carbon atoms, an arylene group having 6 to 14 carbon atoms, heterocyclic group of 4 to 13 carbon atoms , An oxygen atom, a sulfur atom, an imino group having a hydrocarbon group having 1 to 12 carbon atoms (preferably an aryl group or an alkyl group) (for example, phenylimino group, methylimino group, t-butylimino group) is preferable, An alkylene group having 1 to 6 carbon atoms (for example, a methylene group, 1,2-ethylene group, 1,1-dimethylmethylene group), an alkenylene group having 2 carbon atoms (for example, —CH ₂ ═CH ₂ —), and 6 to 10 carbon atoms. Are more preferable, such as a single bond, an alkylene group having 1 to 2 carbon atoms, or an arylene group having 6 to 10 carbon atoms. Arbitrariness.

Z ₃₁ , Z ₄₁ , and Z ₅₁ each independently represent a cycloalkyl ring, an aromatic hydrocarbon ring, or an aromatic heterocyclic ring. In General Formulas (A-3) to (A-5), Z ₃₁ , Z ₄₁ , and Z ₅₁ are condensed with a benzene ring. Z ₃₁ , Z ₄₁ , and Z ₅₁ are preferably aromatic hydrocarbon rings because high element heat resistance and high hole transport ability can be expected, and aromatic hydrocarbon rings having 6 to 10 carbon atoms are preferred. More preferred is a benzene ring.

  Specific examples of the groups represented by the general formulas (A-3) to (A-5) are shown below, but are not limited thereto.

  Specific examples of the groups represented by the general formulas (A-1) and (A-3) to (A-5) include groups exemplified by the following M-1 to M-135 and N1 to N13. . However, it is not limited to these. The groups represented by the general formulas (A-1) and (A-3) to (A-5) are preferably M-1 to M-87, M-132, and N1 to N13, and M-1 to M-73, M-132, and N1 to N13 are more preferable, M-1 to M-31, M-132, and N1 to N13 are still more preferable, and M-6 to M-16, M-18 to M- 31, N2, N3, N4, and N11 are particularly preferable, M-11 to M-16, M-24 to M-29, N2, N3, N4, and N11 are particularly preferable, and M-11 to M-13, M- Most preferred are 24-M-26, N2, N3, N4, and N11.

When the ionization potential (Ip) of the fluorene compound according to the present invention is used for the electron blocking layer, it is necessary to receive holes without any barrier from the material responsible for hole transport in the photoelectric conversion layer. It is necessary to be smaller than Ip of the material that bears. In particular, when an absorbing material having sensitivity in the visible range is selected, the ionization potential of the fluorene compound according to the present invention is preferably 5.8 eV or less in order to adapt to more materials. More preferably, it is less than 5 eV. When Ip is 5.8 eV or less, an effect of exhibiting high charge collection efficiency and high-speed response without generating a barrier to charge transport can be obtained.
Further, Ip is preferably 4.9 eV or more, and more preferably 5.0 eV or more. When Ip is 4.9 eV or more, a higher dark current suppressing effect can be obtained.
The Ip of each compound can be measured by ultraviolet photoelectron spectroscopy (UPS) or an atmospheric photoelectron spectrometer (for example, AC-2 manufactured by Riken Keiki Co., Ltd.).
The Ip of the fluorene compound according to the present invention can be within the above range by changing the substituent bonded to the fluorene skeleton.

  Note that when a material having a structure that interacts strongly with a photoelectric conversion layer including a deep Ea material is used, boiling charges are easily formed at the interface. For example, when a material having high planarity is used for a molecule in contact with a deep Ea material, the planar π electrons and the molecular orbital of the deep Ea material tend to interact with each other, and the boiling charge is reduced. An increasing interface is likely to be formed. Therefore, it is preferable that the fluorene compound according to the present invention does not include a condensed ring structure composed of 5 or more rings. In addition, steric hindrance can be imparted in the sense of suppressing intermolecular interaction, but too bulky steric hindrance inhibits signal charge transport at the interface. It is preferable that the condensed ring structure which consists of these rings is not included.

Hereinafter, although the specific example of the fluorene compound which concerns on this invention is shown, this invention is not limited to the following specific examples. In the formulas (c) and (d), “R ₃₂ , R ₃₇ ”, “R ′ ₃₂ , R ′ ₃₇ ”, “R _4a , R ′ _4a , R _4b , R ′ _4b ” and the like are not the same. In some cases, combinations other than the illustrated structure are possible.
In addition, the partial structure of N1-N13 and A1-A11 in the following compound examples shows the following. Further, Me is a methyl group, Et is an ethyl group, and t-Bu is a tert-butyl group.

Furthermore, the hydrogen atom of the compound represented by the general formula (F-3) may be replaced with a deuterium atom for the purpose of imparting durability during device driving.
The molecular weight of the compound represented by the general formula (F-3) according to the present invention is preferably 500 or more and 2000 or less, and more preferably 500 or more and 1500 or less. When the molecular weight is 500 or more and 2000 or less, the material can be deposited and the heat resistance can be further increased.
Moreover, the compound represented by the general formula (F-3) according to the present invention can be synthesized by applying a known method.

  The amount of the compound represented by the general formula (F-3) according to the present invention is preferably 10 nm or more and 300 nm or less, more preferably 30 nm or more and 150 nm or less, in terms of a single layer in a state after film formation. Especially preferably, they are 50 nm or more and 120 nm or less. When used as a layer inserted between the photoelectric conversion layer and the charge blocking layer, it is preferably 100 nm or less, more preferably 50 nm or less, and still more preferably 20 nm or less in terms of a single layer.

The purity of the compound represented by formula (F-3) according to the present invention used for film formation is preferably 95% or more, more preferably 97% or more, and particularly preferably 99% or more. This material purity can be determined from a chromatogram obtained by monitoring absorbance at 254 nm using high performance liquid chromatography. Examples of the impurities contained include intermediates and by-products mixed during the synthesis, and further include decomposition products of the target compound due to oxidation, reduction, hydrolysis, and the like.
The heavy element impurity contained in the compound represented by formula (F-3) according to the present invention used for film formation is preferably 7000 ppm or less, more preferably 100 ppm or less, and particularly preferably 10 ppm or less. The impurity content can be determined using a high frequency inductively coupled plasma mass spectrometer. The heavy element impurities referred to here are elements of the third and subsequent periods of the periodic table, such as magnesium, iron, copper, palladium, nickel, sodium, potassium, cesium, chlorine, bromine and iodine. ) Is excluded. These heavy element impurities may be contained as a substituent of an ionic compound or an organic compound. These impurities can be removed by operations such as recrystallization, but removal by sublimation purification is preferred.

When the photoelectric conversion element of this invention has a hole blocking layer like the aspect shown in FIG.1 (b), it is preferable to use an electron-accepting material as a material for forming a hole blocking layer. Examples of the electron-accepting material include 1,3-bis (4-tert-butylphenyl-1,3,4-oxadiazolyl) phenylene (OXD-7) and other oxadiazole derivatives, anthraquinodimethane derivatives, and diphenylquinone derivatives. , Bathocuproine, bathophenanthroline, and derivatives thereof, triazole compounds, tris (8-hydroxyquinolinato) aluminum complexes, bis (4-methyl-8-quinolinato) aluminum complexes, distyrylarylene derivatives, silole compounds, etc. Can do. Moreover, even if it is not an electron-accepting organic material, it can be used if it is a material which has sufficient electron transport property. A porphyrin-based compound or a styryl-based compound such as DCM (4-dicyanomethylene-2-methyl-6- (4- (dimethylaminostyryl))-4H pyran) or a 4H pyran-based compound can be used.
Specifically, compounds described in JP-A-2008-72090 (Patent Document 2) are preferable.

The electron blocking layer and the hole blocking layer can be formed by vapor deposition. The vapor deposition may be either physical vapor deposition (PVD) or chemical vapor deposition (CVD), but physical vapor deposition such as vacuum vapor deposition is preferred. In the case of forming a film by vacuum vapor deposition, production conditions such as the degree of vacuum and vapor deposition temperature can be set in accordance with a conventional method. As the condition, the degree of vacuum (in-apparatus pressure) is preferably 1 × 10 ⁻² Pa or less, preferably 1 × 10 ⁻³ Pa or less, and preferably 1 × 10 ⁻⁴ Pa or less. The higher the vacuum, the lower the material decomposition. The temperature of the crucible serving as a vapor deposition source is preferably 200 ° C. or higher and 500 ° C. or lower, and more preferably 300 ° C. or higher and 400 ° C. or lower. The higher the temperature, the higher the film forming speed and the higher the productivity, and the lower the temperature, the more the material can be prevented from decomposing.
The thickness of the electron blocking layer and the hole blocking layer is preferably from 10 nm to 300 nm, more preferably from 30 nm to 150 nm, and particularly preferably from 50 nm to 100 nm. When the thickness is 10 nm or more, a suitable dark current suppressing effect is obtained, and when the thickness is 300 nm or less, a suitable photoelectric conversion efficiency is obtained. Note that a plurality of charge blocking layers may be formed.

(Photoelectric conversion layer)
Moreover, it is preferable that the organic material which comprises the photoelectric converting layer 12 contains at least one of a p-type organic semiconductor and an n-type organic semiconductor.

A p-type organic semiconductor (compound) is a donor-type organic semiconductor (compound), which is mainly represented by a hole-transporting organic compound and refers to an organic compound having a property of easily donating electrons. More specifically, an organic compound having a smaller ionization potential when two organic materials are used in contact with each other. Therefore, any organic compound can be used as the donor organic compound as long as it is an electron-donating organic compound. For example, triarylamine compounds, benzidine compounds, pyrazoline compounds, styrylamine compounds, hydrazone compounds, triphenylmethane compounds, carbazole compounds, polysilane compounds, thiophene compounds, phthalocyanine compounds, cyanine compounds, merocyanine compounds, oxonol compounds, polyamine compounds, indoles Compounds, pyrrole compounds, pyrazole compounds, polyarylene compounds, condensed aromatic carbocyclic compounds (naphthalene derivatives, anthracene derivatives, phenanthrene derivatives, tetracene derivatives, pyrene derivatives, perylene derivatives, fluoranthene derivatives), nitrogen-containing heterocyclic compounds The metal complex etc. which it has as can be used. Not limited to this, as described above, any organic compound having an ionization potential smaller than that of the organic compound used as the n-type (acceptor property) compound may be used as the donor organic semiconductor. Since the material used for the photoelectric conversion layer needs to absorb light, it is preferably a dye, and preferably has a maximum absorption wavelength in the range of 400 to 700 nm, and in the range of 500 to 600 nm for high sensitivity. Those are preferred. The molar extinction coefficient is preferably 10,000 cm ⁻¹ (mol / L) ⁻¹ or more, more preferably 30,000 or more, and particularly preferably 50,000 or more because it is necessary to absorb light. These absorption characteristics can be determined by adjusting a dilute chloroform solution and using a visible light spectral absorption measurement apparatus.

The p-type organic semiconductor is preferably a compound represented by the following general formula (I).
Formula (I)

In the formula, Z ₁ represents an atomic group necessary for forming a 5- or 6-membered ring. L ₁ , L ₂ and L ₃ each represents an unsubstituted methine group or a substituted methine group. D ₁ represents an atomic group. n represents an integer of 0 or more.

Z ₁ represents an atomic group necessary for forming a 5- or 6-membered ring, and the ring formed is preferably one that is usually used as an acidic nucleus in a merocyanine dye, and specific examples thereof include the following: Can be mentioned.

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

(G) 2-thio-2,4-oxazolidinedione (2-thio-2,4- (3H, 5H) -oxazoledione nucleus: for example, 3-ethyl-2-thio-2,4-oxazolidinedione and the like.
(H) Tianaphthenone nucleus: For example, 3 (2H) -thianaphthenone-1,1-dioxide and the like.
(I) 2-thio-2,5-thiazolidinedione nucleus: for example, 3-ethyl-2-thio-2,5-thiazolidinedione and the like.
(J) 2,4-thiazolidinedione nucleus: For example, 2,4-thiazolidinedione, 3-ethyl-2,4-thiazolidinedione, 3-phenyl-2,4-thiazolidinedione, and the like.
(K) Thiazolin-4-one nucleus: For example, 4-thiazolinone, 2-ethyl-4-thiazolinone and the like.
(L) 2,4-imidazolidinedione (hydantoin) nucleus: for example, 2,4-imidazolidinedione, 3-ethyl-2,4-imidazolidinedione, etc.
(M) 2-thio-2,4-imidazolidinedione (2-thiohydantoin) nucleus: for example, 2-thio-2,4-imidazolidinedione, 3-ethyl-2-thio-2,4-imidazolidinedione etc.
(N) Imidazolin-5-one nucleus: for example, 2-propylmercapto-2-imidazolin-5-one and the like.
(O) 3,5-pyrazolidinedione nucleus: for example, 1,2-diphenyl-3,5-pyrazolidinedione, 1,2-dimethyl-3,5-pyrazolidinedione and the like.
(P) Benzothiophen-3-one nucleus: for example, benzothiophen-3-one, oxobenzothiophen-3-one, dioxobenzothiophen-3-one and the like.
(Q) Indanone nucleus: For example, 1-indanone, 3-phenyl-1-indanone, 3-methyl-1-indanone, 3,3-diphenyl-1-indanone, 3,3-dimethyl-1-indanone, and the like.

The ring formed by Z ₁ is preferably a 1,3-dicarbonyl nucleus, a pyrazolinone nucleus, a 2,4,6-triketohexahydropyrimidine nucleus (including a thioketone body, for example, a barbituric acid nucleus, 2-thiobarbitur tool) Acid nucleus), 2-thio-2,4-thiazolidinedione nucleus, 2-thio-2,4-oxazolidinedione nucleus, 2-thio-2,5-thiazolidinedione nucleus, 2,4-thiazolidinedione nucleus, 2, In 4-imidazolidinedione nucleus, 2-thio-2,4-imidazolidinedione nucleus, 2-imidazolin-5-one nucleus, 3,5-pyrazolidinedione nucleus, benzothiophen-3-one nucleus, indanone nucleus More preferably 1,3-dicarbonyl nucleus, 2,4,6-triketohexahydropyrimidine nucleus (including thioketone, for example, barbituric acid nucleus, 2-thiovale nucleus, Bituric acid nucleus), 3,5-pyrazolidinedione nucleus, benzothiophen-3-one nucleus, indanone nucleus, more preferably 1,3-dicarbonyl nucleus, 2,4,6-triketohexahydropyrimidine Nuclei (including thioketone bodies, such as barbituric acid nuclei, 2-thiobarbituric acid nuclei), particularly preferably 1,3-indandione nuclei, barbituric acid nuclei, 2-thiobarbituric acid nuclei and their derivatives. is there.

What is preferable as a ring formed by Z ₁ is represented by the following formula.

Z ³ represents an atomic group necessary for forming a 5- to 6-membered ring. Z ³ can be selected from the ring formed by Z ₁ above, preferably 1,3-dicarbonyl nucleus, 2,4,6-triketohexahydropyrimidine nucleus (including thioketone body), Particularly preferred are a 1,3-indandione nucleus, a barbituric acid nucleus, a 2-thiobarbituric acid nucleus and derivatives thereof.

By controlling the interaction between acceptor parts, when used as a co-deposited film and C _60, we have found that it is possible to express a high hole-transport property. It is possible to control the interaction by introducing an acceptor moiety structure and a steric hindrance substituent. In the barbituric acid nucleus and 2-thiobarbituric acid nucleus, it is possible to control the intermolecular interaction preferably by substituting two hydrogen atoms at two N positions with substituents. Includes a substituent W described later, more preferably an alkyl group, still more preferably a methyl group, an ethyl group, a propyl group, or a butyl group.
When the ring formed by Z ₁ is a 1,3-indandione nucleus, it is preferably a group represented by the following general formula (IV) or a group represented by the following general formula (V).
Formula (IV)

R _{41 to} R ₄₄ each independently represents a hydrogen atom or a substituent.
General formula (V)

R ₄₁ , R ₄₄ and R _{45 to} R ₄₈ each independently represent a hydrogen atom or a substituent.

In the case of the group represented by the general formula (IV), R _{41 to} R ₄₄ each independently represents a hydrogen atom or a substituent. As the substituent, those exemplified as the substituent W can be applied. Further, R _{41 to} R ₄₄ that are adjacent to each other can be bonded to form a ring, and R ₄₂ and R ₄₃ are bonded to form a ring (for example, a benzene ring, a pyridine ring, or a pyrazine ring). The case is preferred. R _{41 to} R ₄₄ are preferably all hydrogen atoms.
The case where the group represented by the general formula (IV) is a group represented by the general formula (V) is preferable.
In the case of the group represented by the general formula (V), R ₄₁ , R ₄₄ , and R _{45 to} R ₄₈ each independently represent a hydrogen atom or a substituent. As the substituent, those exemplified as the substituent W can be applied. R ₄₁ , R ₄₄ , and R _{45 to} R ₄₈ are preferably all hydrogen atoms.

When the ring formed by Z ₁ is a 2,4,6-triketohexahydropyrimidine nucleus (including a thioketone body), it is preferably a group represented by the following general formula (VI).
Formula (VI)

R ₈₁ and R ₈₂ each independently represents a hydrogen atom or a substituent. R ₈₃ represents an oxygen atom, a sulfur atom or a substituent.

In the case of the group represented by the general formula (VI), R ₈₁ and R ₈₂ each independently represents a hydrogen atom or a substituent. As the substituent, those exemplified as the substituent W can be applied. R ₈₁ and R ₈₂ are each independently preferably an alkyl group, an aryl group, or a heterocyclic group (such as 2-pyridyl), and an alkyl group having 1 to 6 carbon atoms (for example, methyl, ethyl, n-propyl, t-butyl). ) Is more preferable.
R ₈₃ represents an oxygen atom, a sulfur atom or a substituent, and R ₈₃ preferably represents an oxygen atom or a sulfur atom. As the substituent, those in which the bond part is a nitrogen atom and those having a carbon atom are preferable. In the case of a nitrogen atom, an alkyl group (1 to 12 carbon atoms) or an aryl group (6 to 12 carbon atoms) is preferable. Specific examples include a methylamino group, an ethylamino group, a butylamino group, a hexylamino group, a phenylamino group, and a naphthylamino group. In the case of a carbon atom, it is sufficient that at least one electron-withdrawing group is substituted. Examples of the electron-withdrawing group include a carbonyl group, a cyano group, a sulfoxide group, a sulfonyl group, or a phosphoryl group. It is good to have. Examples of this substituent include W. R ₈₃ is preferably one that forms a 5-membered or 6-membered ring containing the carbon atom, and specifically includes those having the following structures.

Ph in the above group represents a phenyl group.
L ₁ , L ₂ and L ₃ each independently represents an unsubstituted methine group or a substituted methine group. Substituted methine groups may combine to form a ring (eg, a 6-membered ring such as a benzene ring). Although the substituent of the substituted methine group includes the substituent W, it is preferable that all of L ₁ , L ₂ and L ₃ are unsubstituted methine groups.

  n represents an integer of 0 or more, preferably 0 or more and 3 or less, and more preferably 0. When n is increased, the absorption wavelength region can be made longer, or the thermal decomposition temperature is lowered. N = 0 is preferable in that it has appropriate absorption in the visible region and suppresses thermal decomposition during vapor deposition.

D ₁ represents an atomic group. The D ₁ is preferably a group containing —NR ^a (R ^b ), and further, the D ₁ is an aryl group substituted with —NR ^a (R ^b ) (preferably a phenyl group which may be substituted, or A naphthyl group) is preferred. R ^a and R ^b each independently represents a hydrogen atom or a substituent, and examples of the substituent represented by R ^a and R ^b include the substituent W, preferably an aliphatic hydrocarbon group (preferably An alkyl group which may be substituted, an alkenyl group), an aryl group (preferably a phenyl group which may be substituted), or a heterocyclic group; The heterocycle is preferably a 5-membered ring such as furan, thiophene, pyrrole or oxadiazole.
When R ^a and R ^b are a substituent (preferably an alkyl group or an alkenyl group), the substituent is an aromatic ring (preferably benzene ring) skeleton of an aryl group substituted by —NR ^a (R ^b ). It may combine with a hydrogen atom or a substituent to form a ring (preferably a 6-membered ring). In this case, the case represented by the following general formula (VIII), (IX) or (X) is preferable.
R ^a and R ^b may be bonded to each other to form a ring (preferably a 5-membered or 6-membered ring, more preferably a 6-membered ring), and each of R ^a and R ^b is L A ring (preferably a 5-membered or 6-membered ring, more preferably a 6-membered ring) may be formed by combining with a substituent in (represents any one of L ₁ , L ₂ and L ₃ ).
D ₁ is preferably an aryl group substituted with an amino group at the para position (preferably a phenyl group). In this case, it is preferably represented by the following general formula (II). The amino group may be substituted. Examples of the substituent of the amino group include a substituent W, an aliphatic hydrocarbon group (preferably an alkyl group which may be substituted), an aryl group (preferably an optionally substituted phenyl group), or a heterocyclic group. Is preferred. The amino group is preferably a so-called diaryl group-substituted amino group in which two aryl groups are substituted. In this case, the amino group is preferably represented by the following general formula (III). Further, the substituent of the amino group (preferably an alkyl group or alkenyl group which may be substituted) is bonded to a hydrogen atom of the aromatic ring (preferably benzene ring) skeleton of the aryl group or a ring (preferably 6-membered). Ring) may be formed.
Formula (II)

In the formula, R _{1 to} R ₈ may be independent of each other, and in these substituents, two substituents located in the ortho positions relative to each other may be bonded to each other to form a ring. n2 represents an integer of 0 to 3, preferably 0 to 2, and particularly preferably 0 or 1.
Formula (III)

In formula, R < ₁₁ > -R < ₁₆ >, R < ₂₀ > -R < ₂₄ >, R < ₃₀ > -R < ₃₄ > represents a hydrogen atom or a substituent each independently. Moreover, in these substituents, two substituents located at ortho positions relative to each other may be bonded to each other to form a ring. n3 represents an integer of 0 to 3, preferably 0 to 2, and particularly preferably 0 or 1.

When R ^a and R ^b are an aliphatic hydrocarbon group, an aryl group or a heterocyclic group, an alkyl group, an alkenyl group, an aryl group, an alkoxy group, an aryloxy group, an acyl group, an alkoxycarbonyl group, Aryloxycarbonyl group, acylamino group, sulfonylamino group, sulfonyl group, silyl group, aromatic heterocyclic group, more preferably alkyl group, alkenyl group, aryl group, alkoxy group, aryloxy group, silyl group, aromatic A heterocyclic group, more preferably an alkyl group, an aryl group, an alkoxy group, an aryloxy group, a silyl group, and an aromatic heterocyclic group. As specific examples, those exemplified for the substituent W can be applied.

R ^a and R ^b are preferably an alkyl group, an aryl group, or an aromatic heterocyclic group. R ^a and R ^b are particularly preferably an alkyl group, an alkylene group linked to L to form a ring, or an aryl group, and more preferably an alkyl group having 1 to 8 carbon atoms, linked to L to 5 to 6 An alkylene group forming a member ring, or a substituted or unsubstituted phenyl group, more preferably an alkyl group having 1 to 8 carbon atoms, or a substituted or unsubstituted phenyl group.

It is also preferable that D ₁ is represented by the following general formula (VII).
Formula (VII)

In the formula, R _{91 to} R ₉₈ each independently represent a hydrogen atom or a substituent. m represents an integer of 0 or more. m is preferably 0 or 1. Rx and Ry each independently represent a hydrogen atom or a substituent. When m is 2 or more, Rx and Ry bonded to each 6-membered ring may be different substituents. R ₉₁ and R ₉₂ , R ₉₂ and Rx, Rx and R ₉₄ , R ₉₄ and R ₉₇ , R ₉₃ and Ry, Ry and R ₉₅ , R ₉₅ and R ₉₆ , R ₉₇ and R ₉₈ are independent of each other. Thus, a ring may be formed. In addition, the bond with L ₃ (L ₁ when n is 0) may be at the position of R ₉₁ , R ₉₂ , R ₉₃ , and in that case, as the bond with L ₃ in the general formula (VII) Substituents or hydrogen atoms corresponding to R ₉₁ , R ₉₂ , and R ₉₃ may be bonded to the indicated sites, and adjacent Rs may be bonded to form a ring. Here, “adjacent Rs may be bonded to form a ring” means that, for example, when R ₉₁ is a bonding part with L ₃ (L ₁ when n is 0), If R ₉₀ is bonded to the bonding portion of formula (VII), R ₉₀ and R ₉₃ may bond to form a ring, and R ₉₂ is L ₃ (when n is 0, L ₉₀ is L ₁ ), when R ₉₀ is bonded to the bonded portion of formula (VII), R ₉₀ and R ₉₁ , and R ₉₀ and R ₉₃ are bonded to form a ring. In addition, when R ₉₃ is a bonding portion with L ₃ (L ₁ when n is 0), assuming that R ₉₀ is bonded to the bonding portion of general formula (VII), R ₉₀ R ₉₁ , R ₉₁ and R ₉₂ are bonded to each other to form a ring.
The above ring is preferably a benzene ring.
The substituent of R _{91 to} R ₉₈ , Rx, and Ry includes the substituent W.
R _{91 to} R ₉₆ are preferably all hydrogen atoms, and Rx and Ry are preferably both hydrogen atoms. R _{91 to} R ₉₆ are preferably hydrogen atoms, and Rx and Ry are also preferably hydrogen atoms.
R ₉₇ and R ₉₈ each independently represent a phenyl group that may be substituted, and examples of the substituent include the substituent W, and an unsubstituted phenyl group is preferable.
m represents an integer of 0 or more, but 0 or 1 is preferable.

It is also preferred that D ₁ is a group represented by the general formula (VIII), (IX) or (X).
Formula (VIII)

In the formula, R _{51 to} R ₅₄ each independently represent hydrogen or a substituent. Substituent W is mentioned as this substituent. R ₅₂ and R ₅₃ , or R ₅₁ and R ₅₂ may be linked to form a ring.
Formula (IX)

In the formula, R _{61 to} R ₆₄ each independently represent hydrogen or a substituent. Substituent W is mentioned as this substituent. R ₆₂ and R ₆₃ , or R ₆₁ and R ₆₂ may be linked to form a ring.
Formula (X)

_Wherein, R 71 _{to R 73} each independently represents hydrogen or a substituent. Substituent W is mentioned as this substituent. R ₇₂ and R ₇₃ may be linked to form a ring.

The group represented by the general formula (II) or (III) is more preferably used as the D ₁ .
In general formula (II), R < ₁ > -R < ₆ > represents a hydrogen atom or a substituent each independently. R ₁ and R ₂ , R ₃ and R ₄ , R ₅ and R ₆ , R ₂ and R ₅ , and R ₄ and R ₆ may be bonded to each other to form a ring.
Examples of the substituent in R _{1 to} R ₄ include the substituent W, preferably R _{1 to} R ₄ are a hydrogen atom, or R ₂ and R ₅ or R ₄ and R ₆ form a 5-membered ring. More preferably, R _{1 to} R ₄ are all hydrogen atoms.
The substituent in R ₅ and R ₆ includes the substituent W, and among the substituents, a substituted or unsubstituted aryl group is preferable, and the substituent of the substituted aryl group is an alkyl group (for example, a methyl group, an ethyl group, or the like). Group) and an aryl group (for example, phenyl group, naphthylene group, phenanthryl group, anthryl group) are preferable. R ₅ and R ₆ are preferably a phenyl group, an alkyl-substituted phenyl group, a phenyl-substituted phenyl group, a naphthyl group, a phenanthryl group, an anthryl group, or a fluorenyl group (preferably a 9,9′-dimethyl-2-fluorenyl group).
In general formula (III), R < ₁₁ > -R < ₁₄ >, R < ₂₀ > -R < ₂₄ >, R < ₃₀ > -R < ₃₄ > represents a hydrogen atom or a substituent each independently. R _{11 to} R ₁₄ , R _{20 to} R ₂₄ , and R _{30 to} R ₃₄ may be bonded to each other to form a ring. As an example of the ring formation, R ₁₁ and R ₁₂ , R ₁₃ and R ₁₄ are bonded to form a benzene ring, and two adjacent R _{20 to} R ₂₄ (R ₂₄ and R ₂₃ , R ₂₃ and R ₂₀ , R ₂₀ and R ₂₁ , R ₂₁ and R ₂₂ ) are bonded to form two benzene rings adjacent to R _{30 to} R ₃₄ (R ₃₄ and R ₃₃ , R ₃₃ and R ₃₀ , R ₃₀ and R ₃₁ , R ₃₁ and R ₃₂ ) are combined to form a benzene ring, and R ₂₂ and R ₃₄ are combined to form a 5-membered ring with an N atom.
Examples of the substituent represented by R _{11 to} R ₁₄ , R _{20 to} R ₂₄ , and R _{30 to} R ₃₄ include the substituent W, but preferably an alkyl group (for example, a methyl group or an ethyl group) or an aryl group (for example, , Phenyl group, naphthyl group), and these groups may be further substituted with a substituent W (preferably an aryl group). Among _them, preferred is a case R _{20, R 30} is a substituent, and the other _{R 11 ~R 14, R 21 ~R} 24, R 31 ~R 34 is more preferably be a hydrogen atom.

The compound represented by the general formula (I) is preferably a compound represented by the following general formula (pI).
Formula (pI)

In the formula, Z ₁ represents a ring containing two carbon atoms and represents a 5-membered ring, a 6-membered ring, or a condensed ring containing at least one of a 5-membered ring and a 6-membered ring. L ₁ , L ₂ and L ₃ each independently represents an unsubstituted methine group or a substituted methine group. n ₁ represents an integer of 0 or more. _{Rp 1, Rp 2, Rp 3} , Rp 4, Rp 5, Rp 6 independently represents a hydrogen atom or a substituent. Rp ₁ and Rp ₂ , Rp ₂ and Rp ₃ , Rp ₄ and Rp ₅ , Rp ₅ and Rp ₆ may be bonded to each other to form a ring. Rp ₂₁ and Rp ₂₂ each independently represent a substituted aryl group, an unsubstituted aryl group, a substituted heteroaryl group, or an unsubstituted heteroaryl group.

As a photoelectric conversion material, a compound having a naphthylene group as a connecting part of a donor part (site of —NRp ₂₁ Rp ₂₂ ) / acceptor part (site bonded to a naphthylene group via L _{1 to} L ₃ ) as described above. By using it together with fullerenes, a photoelectric conversion element having excellent heat resistance and high-speed response can be obtained. This is considered that the interaction with the fullerenes is improved and the response speed is improved by using a naphthylene group as the connecting part of the donor part / acceptor part. Moreover, the said compound has sufficient sensitivity.

In the general formula (pI), L ₁ , L ₂ and L ₃ each independently represent an unsubstituted methine group or a substituted methine group. The substituents in the substituted methine group may be bonded to form a ring. A 6-membered ring (for example, benzene ring etc.) is mentioned as a ring. Examples of the substituent of the substituted methine group include the substituent W described later. L ₁ , L ₂ and L ₃ are preferably all unsubstituted methine groups.

n ₁ represents an integer of 0 or more, preferably 0 or more and 3 or less, and more preferably 0. If increased n _1, can be absorbed wavelength region to a long wavelength, the thermal decomposition temperature becomes low. N ₁ = 0 is preferable in that it has appropriate absorption in the visible region and suppresses thermal decomposition during vapor deposition.

Rp _{1 to} Rp ₆ each independently represent a hydrogen atom or a substituent. If Rp ₁ to Rp ₆ represents a _substituent, but examples of a substituent Rp 1 to Rp ₆ represents include the substituent W described below, in particular a halogen atom, an alkyl group, an aryl group, a heterocyclic group, hydroxy group, A nitro group, alkoxy group, aryloxy group, heterocyclic oxy group, amino group, alkylthio group, arylthio group, alkenyl group, and cyano group heterocyclic thio group are preferred.
Rp _{1 to} Rp ₆ are each independently a hydrogen atom, halogen atom, alkyl group, aryl group, heterocyclic group, hydroxy group, nitro group, alkoxy group, aryloxy group, heterocyclic oxy group, amino group, alkylthio group , An arylthio group, an alkenyl group, a cyano group or a heterocyclic thio group, more preferably a hydrogen atom, an alkyl group, an aryl group or a heterocyclic group, a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or a carbon number. A 6-20 aryl group and a C4-C16 heterocyclic group are more preferable, a hydrogen atom, a C1-C12 alkyl group, and a C6-C14 aryl group are still more preferable, a hydrogen atom, carbon number 1 -6 alkyl groups and C6-C10 aryl groups are more preferred, and hydrogen atoms are particularly preferred. In the case of an alkyl group, there may be a branch. _Also, if Rp 1 to Rp ₆ is a substituent, it may have further substituents. Examples of the further substituent include the substituent W described later.
Preferable specific examples of Rp _{1 to} Rp ₆ include a hydrogen atom, a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, a cyclohexyl group, a phenyl group, and a naphthyl group.

Rp ₁ and Rp ₂ , Rp ₂ and Rp ₃ , Rp ₄ and Rp ₅ , Rp ₅ and Rp ₆ may be bonded to each other to form a ring. Examples of the ring formed include ring R described later. Preferred are a benzene ring, a naphthalene ring, an anthracene ring, a pyridine ring, a pyrimidine ring and the like.

Rp ₂₁ and Rp ₂₂ each independently represent a substituted aryl group, an unsubstituted aryl group, a substituted heteroaryl group, or an unsubstituted heteroaryl group.
It is preferable that both Rp ₂₁ and Rp ₂₂ are not unsubstituted phenyl groups.
The aryl group Rp _{21, Rp 22} represents preferably an aryl group having 6 to 30 carbon atoms, more preferably an aryl group having 6 to 20 carbon atoms. Specific examples of the aryl group include a phenyl group, a naphthyl group, a biphenylyl group, a terphenyl group, an anthryl group, and a fluorenyl group.
Examples of the substituent of the substituted aryl group in Rp ₂₁ and Rp ₂₂ include an alkyl group (eg, methyl group, ethyl group, t-butyl group), an alkoxy group (eg, methoxy group, ethoxy group, isopropoxy group), and aryl group (For example, phenyl group, naphthyl group, phenanthryl group, anthryl group) and heteroaryl groups (for example, thienyl group, furanyl group, pyridyl group, carbazolyl group) are preferable.

The aryl group or substituted aryl group represented by Rp ₂₁ or Rp ₂₂ is preferably a phenyl group, a substituted phenyl group, a biphenyl group, a naphthyl group, a phenanthryl group, an anthryl group, a fluorenyl group, or a substituted fluorenyl group (preferably 9,9 ′ -Dialkyl-2-fluorenyl group).

When Rp ₂₁ and Rp ₂₂ are heteroaryl groups, the heteroaryl group is preferably a heteroaryl group consisting of a 5-membered, 6-membered or 7-membered ring or a condensed ring thereof. Examples of the hetero atom contained in the heteroaryl group include an oxygen atom, a sulfur atom, and a nitrogen atom. Specific examples of the ring constituting the heteroaryl group include a furan ring, a thiophene ring, a pyrrole ring, a pyrroline ring, a pyrrolidine ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, an imidazole ring, an imidazoline ring, and an imidazolidine. Ring, pyrazole ring, pyrazoline ring, pyrazolidine ring, triazole ring, furazane ring, tetrazole ring, pyran ring, thiine ring, pyridine ring, piperidine ring, oxazine ring, morpholine ring, thiazine ring, pyridazine ring, pyrimidine ring, pyrazine ring, Examples include a piperazine ring and a triazine ring.
As the condensed ring, benzofuran ring, isobenzofuran ring, benzothiophene ring, indole ring, indoline ring, isoindole ring, benzoxazole ring, benzothiazole ring, indazole ring, benzimidazole ring, quinoline ring, isoquinoline ring, cinnoline ring, Phthalazine ring, quinazoline ring, quinoxaline ring, dibenzofuran ring, carbazole ring, xanthene ring, acridine ring, phenanthridine ring, phenanthroline ring, phenazine ring, phenoxazine ring, thianthrene ring, thienothiophene ring, indolizine ring, quinolidine ring, A quinuclidine ring, a naphthyridine ring, a purine ring, a pteridine ring, etc. are mentioned.

Examples of the substituent of the substituted heteroaryl group in Rp ₂₁ and Rp ₂₂ include an alkyl group (for example, methyl group, ethyl group, t-butyl group), an alkoxy group (for example, methoxy group, ethoxy group, isopropoxy group), aryl A group (for example, phenyl group, naphthyl group, phenanthryl group, anthryl group) or a heteroaryl group (for example, thienyl group, furanyl group, pyridyl group, carbazolyl group) is preferable.
The ring constituting the heteroaryl group or substituted heteroaryl group represented by Rp ₂₁ or Rp ₂₂ is preferably a thiophene ring, a substituted thiophene ring, a furan ring, a substituted furan ring, a thienothiophene ring, a substituted thienothiophene ring, or a carbazolyl group. It is.

Rp ₂₁ and Rp ₂₂ are each independently preferably a phenyl group, a naphthyl group, a fluorenyl group, a biphenyl group, an anthracenyl group, or a phenanthrenyl group, and more preferably a phenyl group, a naphthyl group, or a fluorenyl group. The preferred substituents in the case of Rp _21, Rp ₂₂ has a substituent, an alkyl group, a halogenated alkyl group, an alkoxy group, an aryl group or a heteroaryl group, more preferably a methyl group, an isopropyl group, t- butyl Group, trifluoromethyl group, phenyl group, or carbazolyl group.

When Z ₁ is a group represented by the general formula (VI) or a group represented by the general formula (VII), the compound represented by the general formula (pI) is represented by the following general formula (pII), respectively. Or a compound represented by the following general formula (pIII).
The compound represented by the general formula (pI) is preferably a compound represented by the following general formula (pII) or a compound represented by the following general formula (pIII).

  General formula (pII)

In the formula, L ₁ , L ₂ , L ₃ , n ₁ , Rp ₁ , Rp ₂ , Rp ₃ , Rp ₄ , Rp ₅ , Rp ₆ , Rp ₂₁ , Rp ₂₂ are synonymous with the general formula (pI), The preferable range is also the same. Rp ₄₁ , Rp ₄₂ , Rp ₄₃ , Rp ₄₄ are synonymous with R ₄₁ , R ₄₂ , R ₄₃ , R ₄₄ in general formula (IV), and preferred ranges are also the same.

  General formula (pIII)

In the formula, L ₁ , L ₂ , L ₃ , n ₁ , Rp ₁ , Rp ₂ , Rp ₃ , Rp ₄ , Rp ₅ , Rp ₆ , Rp ₂₁ , Rp ₂₂ are synonymous with the general formula (pI), The preferable range is also the same. Rp ₅₁ , Rp ₅₂ , Rp ₅₃ , Rp ₅₄ , Rp ₅₅ , Rp ₅₆ are synonymous with R ₄₁ , R ₄₄ , R ₄₅ , R ₄₆ , R ₄₇ , R ₄₈ in the general formula (V), and preferred ranges are also the same. It is.

The compound represented by the general formula (pI) is preferably a compound represented by the following general formula (pIV).
General formula (pIV)

In the formula, Z ₁ , L ₁ , L ₂ , L ₃ , n ₁ , Rp ₁ , Rp ₂ , Rp ₃ , Rp ₄ , Rp ₅ , Rp ₆ are synonymous with the general formula (pI), and preferred ranges are also included. It is the same.
Rp _{7 to} Rp ₁₁ and Rp _{12 to} Rp ₁₆ each independently represent a hydrogen atom or a substituent. However, the case where all of Rp _{7 to} Rp ₁₁ and Rp _{12 to} Rp ₁₆ are hydrogen atoms is excluded. Further, adjacent ones of Rp _{7 to} Rp ₁₁ and Rp _{12 to} Rp ₁₆ may be bonded to each other to form a ring. Further, Rp ₃ and Rp ₇ , Rp ₆ and Rp ₁₆ may be connected to each other.

In General Formula (pIV), Rp _{7 to} Rp ₁₁ and Rp _{12 to} Rp ₁₆ each independently represent a hydrogen atom or a substituent. However, all of Rp _{7 to} Rp ₁₁ and Rp _{12 to} Rp ₁₆ do not become hydrogen atoms. In the case where Rp ₃ and Rp _7, or Rp ₆ and _{Rp 16} are linked, the other of _{Rp 8 ~Rp 11, Rp 12 ~Rp} 15 may be all a hydrogen atom.
When Rp _{7 to} Rp ₁₁ , Rp _{12 to} Rp ₁₆ represent a substituent, examples of the substituent represented by Rp _{7 to} Rp ₁₁ , Rp _{12 to} Rp ₁₆ include the substituent W described below. Group, aryl group, heterocyclic group, hydroxy group, nitro group, alkoxy group, aryloxy group, heterocyclic oxy group, amino group, alkylthio group, arylthio group, alkenyl group, cyano group and heterocyclic thio group are preferred.
Rp _{7 to} Rp ₁₁ and Rp _{12 to} Rp ₁₆ are each independently a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a hydroxy group, a nitro group, an alkoxy group, an aryloxy group, or a heterocyclic oxy group. , An amino group, an alkylthio group, an arylthio group, an alkenyl group, a cyano group or a heterocyclic thio group, and more preferably a hydrogen atom, an alkyl group, an alkenyl group, an alkoxy group, an aryl group, an aryloxy group, or a heterocyclic group. Preferably, a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms A heterocyclic group consisting of a 5-membered, 6-membered or 7-membered ring or a condensed ring thereof is more preferred, a hydrogen atom, an alkyl group having 1 to 12 carbon atoms. An alkenyl group having 2 to 12 carbon atoms, an alkyloxy group having 1 to 12 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, a 5-membered or 6-membered ring, or a condensed ring thereof. The heterocyclic group is more preferable.
In the case of an alkyl group, it may be linear or branched. Examples of the hetero atom contained in the heterocyclic group include an oxygen atom, a sulfur atom, and a nitrogen atom.
Specific examples of the alkyl group, alkenyl group, aryl group and the like include groups exemplified by the alkyl group, alkenyl group, and aryl group of the substituent W described later.

Further, adjacent ones of Rp _{7 to} Rp ₁₁ and Rp _{12 to} Rp ₁₆ may be bonded to each other to form a ring. Examples of the ring formed include ring R described later. The ring to be formed is preferably a benzene ring, a naphthalene ring, an anthracene ring, a pyridine ring, a pyrimidine ring or the like.
Further, Rp ₃ and Rp ₇ , Rp ₆ and Rp ₁₆ may be connected to each other. When Rp ₃ and Rp ₇ or Rp ₆ and Rp ₁₆ are connected, it becomes a condensed ring of 4 or more rings containing a naphthylene group and a phenyl group. The linkage between Rp ₃ and Rp ₇ or Rp ₆ and Rp ₁₆ may be a single bond.

The compound represented by the general formula (I) is a compound described in JP 2000-297068 A, and a compound not described in the above publication can also be produced according to the synthesis method described in the above publication. .
Specific examples of the compound represented by the general formula (I) are shown below, but the present invention is not limited thereto.

  Moreover, the compound represented by the said general formula (I) is compoundable according to the following reaction, for example.

In the above formula, Rp ₁ , Rp ₂ , Rp ₃ , Rp ₄ , Rp ₅ , Rp ₆ , Rp ₂₁ , Rp ₂₂ are as defined above.
In the above synthesis examples, the case where Z ₁ is a 1,3-benzoindandione nucleus among the compounds represented by the general formula (I) has been described, but the case where Z ₁ has another structure is also described above. It can be synthesized in the same manner as described above by changing 3-benzoindandione to a compound that becomes an acidic nucleus in another merocyanine dye.

An n-type organic semiconductor (compound) is an acceptor organic semiconductor (compound), which is represented by mainly an electron-transporting organic compound and refers to an organic compound having a property of easily accepting electrons. More specifically, the organic compound having the higher electron affinity when two organic compounds are used in contact with each other.
Therefore, as the acceptor organic compound, any organic compound can be used as long as it is an electron-accepting organic compound. For example, condensed aromatic carbocyclic compounds (naphthalene, anthracene, fullerene, phenanthrene, tetracene, pyrene, perylene, fluoranthene, or derivatives thereof), 5- to 7-membered heterocyclic compounds containing a nitrogen atom, an oxygen atom, or a sulfur atom (E.g. pyridine, pyrazine, pyrimidine, pyridazine, triazine, quinoline, quinoxaline, quinazoline, phthalazine, cinnoline, isoquinoline, pteridine, acridine, phenazine, phenanthroline, tetrazole, pyrazole, imidazole, thiazole, oxazole, indazole, benzimidazole, benzotriazole, Benzoxazole, benzothiazole, carbazole, purine, triazolopyridazine, triazolopyrimidine, tetrazaindene, oxadiazo , Imidazopyridine, pyralidine, pyrrolopyridine, thiadiazolopyridine, dibenzazepine, tribenzazepine, etc.), polyarylene compounds, fluorene compounds, cyclopentadiene compounds, silyl compounds, nitrogen-containing heterocyclic compounds as ligands Etc. Note that the present invention is not limited thereto, and as described above, any organic compound having an electron affinity higher than that of the organic compound used as the donor organic compound may be used as the acceptor organic semiconductor.

  As the n-type organic semiconductor, a compound having an Ea of 3.4 to 5.2 eV is preferable, and a compound having an Ea of 3.9 to 4.5 eV is particularly preferable. Specifically, it is preferable to use fullerene or a fullerene derivative.

Fullerenes are fullerene C ₆₀ , fullerene C ₇₀ , fullerene C ₇₆ , fullerene C ₇₈ , fullerene C ₈₀ , fullerene C ₈₂ , fullerene C ₈₄ , fullerene C ₉₀ , fullerene C ₉₆ , fullerene C ₂₄₀ , fullerene ₅₄₀ , mixed fullerene Represents a fullerene nanotube, and a fullerene derivative represents a compound having a substituent added thereto. As the substituent, an alkyl group, an aryl group, or a heterocyclic group is preferable.
As a fullerene derivative, the compound of patent document 1 is preferable.

  In addition, as for fullerene and fullerene derivatives, there are quarterly chemical reviews No. edited by the Chemical Society of Japan. 43 (1999), JP-A-10-167994, JP-A-11-255508, JP-A-11-255509, JP-A-2002-241323, JP-A-2003-19681, and the like. It can also be used.

  The content of fullerene and fullerene derivative is preferably 50% or more (molar ratio) of the amount of the material forming the mixed film in the mixed layer with the p-type material, and more than 200% More preferably, the amount is 300% or more.

  In the chemical structure of the organic compound constituting the photoelectric conversion layer and the charge blocking layer of the present invention, hydrogen is preferably partially or completely deuterated. It can be expected that deuteration suppresses the reactivity of the hydrogen and improves device durability.

[Material property parameters (N / C ratio, O / C ratio, refractive index, carrier concentration)]
(1) N / C ratio: The chemical structure of the organic compound constituting the photoelectric conversion layer and the charge blocking layer of the present invention is the number of nitrogen atoms and carbon atoms in the film in order to control electron donating ability and electron accepting ability. The ratio (N / C) is important. N / C is preferably 0 or more and 0.10 or less, and more preferably 0 or more and 0.05 or less.
(2) O / C ratio: The chemical structure of the organic compound constituting the photoelectric conversion layer and the charge blocking layer of the present invention is the number of oxygen atoms and carbon atoms in the film in order to control electron donating ability and electron accepting ability. The ratio (O / C) is important. O / C is preferably 0 or more and 0.3 or less, and more preferably 0 or more and 0.10 or less.
(3) Refractive index: The refractive index of the organic compound constituting the photoelectric conversion layer and the charge blocking layer of the present invention can be measured by ellipsometry, and is preferably 1.5 or more and 3.0 or less at 600 nm. It increases when a fullerene or a fullerene derivative is contained in the photoelectric conversion layer and the charge blocking layer.
(4) Carrier concentration: The carrier concentration of the organic compound constituting the photoelectric conversion layer and the charge blocking layer of the present invention is preferably 1.0 × 10 ¹⁰ pieces / cm ³ or more and 1.0 × 10 ²⁰ pieces / cm 3 or less. The higher the mobility, the higher the sensitivity and the higher the element response speed, which is preferable. At room temperature, the electric field strength of 3 × 10 ⁵ V / cm is preferably 1 × 10 ⁻⁵ cm ² / Vs or higher, and preferably 1 × 10 ⁻⁴ cm ² / Vs or higher. Is more preferable. The mobility can be measured by a TOF (Time Of Flight) method.

[Material production method (storage method, particle size)]
(1) Storage method: The organic compounds constituting the photoelectric conversion layer and the charge blocking layer of the present invention are preferably stored in a sealed container. The sealed container is preferably made of a moisture-proof material, and the moisture content (water content) of the organic compound is preferably 0.1% by weight or less in the sealed container. The moisture content can also be measured by the Karl Fischer method (standardized by Japanese Industrial Standards JIS) and thermal analysis (differential thermal analysis DTA, differential scanning calorimetry DSC). As the moisture-proof material, a glass material, a metal material, a plastic material, or a composite material thereof is preferably used. A glass ampoule is more preferable. Moisture permeability coefficient-proof wet materials, 0.01g ^/ m 2 · day or less, preferably, 0.005g ^/ m 2 · day or less, and more preferably not more than 0.001g ^/ m 2 · day. The moisture-proof material preferably has a low transmittance of ultraviolet rays (UV light) and visible light, preferably 50% or less, more preferably 40% or less, and still more preferably 30% or less. The moisture-proof material preferably has a low oxygen permeability, preferably 50 ml / atm · m ² · day or less at 25 ° C., more preferably 10 ml / atm · m ² · day or less, still more preferably 1 0.0 ml / atm · m ² · day or less. It is desirable that the inside of the sealed container for storing the material and the storage of the sealed container be replaced with an inert gas (nitrogen, argon, etc.).
(2) Particle size: The powder particle size of the organic compound constituting the photoelectric conversion layer and the charge blocking layer of the present invention is 10 μm to 200 μm, preferably 20 μm to 180 μm, and the average particle size represented by D50% is preferably 40 μm to 150 μm is more preferable, and 50 μm to 120 μm is particularly preferable. If it is less than 10 μm, a stable deposition rate cannot be maintained due to generation of static electricity due to the association of particles or increased contact between particles, and if it exceeds 200 μm, the change in the amount of falling particles per unit time increases. Again, a stable deposition rate may not be maintained. The D50% indicates an average particle diameter when the large side and the small side are equal when the powder is divided into two from a certain particle size.

[Film forming method]
The photoelectric conversion layer and the charge blocking layer of the present invention can be formed by a dry film forming method or a wet film forming method. As a dry film forming method, a vapor deposition method, a sputtering method, or the like can be used. The wet film formation method is an effective film formation method for increasing the area of the organic chemical layer. The vapor deposition may be either physical vapor deposition (PVD) or chemical vapor deposition (CVD), but physical vapor deposition such as vacuum vapor deposition is preferred. In the case of forming a film by vacuum vapor deposition, production conditions such as the degree of vacuum and vapor deposition temperature can be set in accordance with a conventional method.
As a wet film forming method, an inkjet method, a spray method, a nozzle printing method, a spin coating method, a dip coating method, a casting method, a die coating method, a roll coating method, a bar coating method, a gravure coating method, etc. can be used. From the viewpoint of high-precision patterning, the inkjet method is preferable.

  The thickness of the photoelectric conversion layer is preferably from 10 nm to 1000 nm, more preferably from 50 nm to 800 nm, and particularly preferably from 100 nm to 500 nm. By setting it to 10 nm or more, a suitable dark current suppressing effect is obtained, and by setting it to 1000 nm or less, suitable photoelectric conversion efficiency is obtained.

The photoelectric conversion element of the present invention is preferably manufactured by a manufacturing method including a step of forming the photoelectric conversion layer and the electron blocking layer by vacuum heating deposition.
In the present invention, a photoelectric conversion element in which the photoelectric conversion film has a structure of two or more layers including an electron blocking layer and a photoelectric conversion layer is preferable, and the compound represented by the general formula (F-3) according to the present invention in the electron blocking layer And the photoelectric conversion layer preferably contains a compound of the general formula (I) and fullerene or a fullerene derivative. This configuration example has already been shown as FIG. With respect to the voltage application method in this configuration, it is preferable to apply so that the electron blocking layer side is a cathode and the photoelectric conversion layer side is an anode. In the case of the configuration of FIG. 1B, the method in which the electron blocking material side becomes the cathode is also preferable. Although an applied voltage can be selected in the range of 0-100V, 1-40V is preferable and the range of 3-20V is especially preferable. If the voltage is high, the efficiency is high, but the dark current increases. If the voltage is low, the dark current is low but the efficiency is low, so there is an appropriate range. In addition, when the photoelectric conversion element according to the present invention is used as an optical sensor, or when it is incorporated in an imaging element, voltage can be applied by the same method as described above.
The present invention is a method for driving the photoelectric conversion element, the optical sensor, or the imaging element, wherein the electrode in contact with the electron blocking layer is a cathode and the other electrode is an anode, and the voltage is greater than 0V and less than 100V. The present invention also relates to a driving method for applying.

[Film density]
The photoelectric conversion layer of the present invention is preferably formed in a state where fullerene or a fullerene derivative and at least one other material are mixed or laminated. The film density of the photoelectric conversion layer of the present invention is more preferably 1.40 g / cm ³ or more 2.00 g / cm ³ or less is preferably 1.50 g / cm ³ or more 1.70 g / cm ³ or less.

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

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

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

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

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

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

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

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

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

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

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

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

  The manufacturing method of the image sensor 100 is as follows.

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

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

  Also in the method of manufacturing the image sensor 100, a step of placing the image sensor 100 being manufactured under non-vacuum is added between the process of forming the photoelectric conversion layer included in the photoelectric conversion film 107 and the process of forming the sealing layer 110. Even so, performance degradation of the plurality of photoelectric conversion elements can be prevented. By adding this step, it is possible to suppress the manufacturing cost while preventing the performance degradation of the image sensor 100.

Below, the detail of the sealing layer 110 of the component of the image pick-up element 100 mentioned above is demonstrated.
[Sealing layer]
The following conditions are required for the sealing layer 110.
First, it is possible to protect the photoelectric conversion layer by preventing intrusion of factors that degrade the organic photoelectric conversion material contained in the solution, plasma, and the like in each manufacturing process of the device.
Secondly, after the device is manufactured, the intrusion of factors such as water molecules that degrade the organic photoelectric conversion material is prevented, and the deterioration of the photoelectric conversion film 107 is prevented over a long period of storage / use.
Third, when the sealing layer 110 is formed, the already formed photoelectric conversion layer is not deteriorated.
Fourth, since incident light reaches the photoelectric conversion film 107 through the sealing layer 110, the sealing layer 110 must be transparent to light having a wavelength detected by the photoelectric conversion film 107.

  The sealing layer 110 can be composed of a thin film made of a single material. However, by providing a multi-layered structure and providing each layer with a different function, stress relaxation of the entire sealing layer 110 and generation of dust during the manufacturing process are possible. Such effects as the suppression of defects such as cracks and pinholes caused by the above, and the optimization of material development can be expected. For example, the sealing layer 110 is formed by laminating a “sealing auxiliary layer” having a function that is difficult to achieve on the layer that serves the original purpose of preventing the penetration of deterioration factors such as water molecules. A two-layer structure can be formed. Although it is possible to have three or more layers, it is preferable that the number of layers is as small as possible in consideration of manufacturing costs.

[Formation of Sealing Layer 110 by Atomic Layer Deposition Method (ALD Method)]
The performance of the photoelectric conversion material is significantly deteriorated due to the presence of deterioration factors such as water molecules. Therefore, it is necessary to cover and seal the entire photoelectric conversion film with ceramics such as dense metal oxide / metal nitride / metal nitride oxide, diamond-like carbon (DLC), etc. that do not allow water molecules to permeate. Conventionally, aluminum oxide, silicon oxide, silicon nitride, silicon nitride oxide, a laminated structure thereof, a laminated structure of them and an organic polymer, or the like is used as a sealing layer to form various vacuum film forming techniques. However, since these conventional sealing layers are difficult to grow on a step due to structures on the substrate surface, minute defects on the substrate surface, particles adhering to the substrate surface, etc. (because the step becomes a shadow), In comparison, the film thickness is significantly reduced. For this reason, the stepped portion becomes a path through which the deterioration factor penetrates. In order to completely cover this step with the sealing layer, it is preferable to form the film so as to have a film thickness of 1 μm or more in the flat portion, thereby increasing the thickness of the entire sealing layer.

  In the image sensor 100 having a pixel size of less than 2 μm, particularly about 1 μm, if the distance between the color filter 111 and the photoelectric conversion layer, that is, the film thickness of the sealing layer 110 is large, incident light is diffracted / diverged in the sealing layer 110. As a result, color mixing occurs. For this reason, the imaging element 100 having a pixel size of about 1 μm is preferably a sealing layer material / manufacturing method that does not deteriorate the element performance even when the film thickness of the entire sealing layer 110 is reduced.

  The atomic layer deposition (ALD) method is a kind of CVD method, and adsorption / reaction of organometallic compound molecules, metal halide molecules, and metal hydride molecules, which are thin film materials, onto the substrate surface and unreacted groups contained therein. Is a technique for forming a thin film by alternately repeating decomposition. When the thin film material reaches the substrate surface, it is in the above-mentioned low molecular state, so that the thin film can be grown in a very small space where the low molecule can enter. For this reason, the step portion, which was difficult with the conventional thin film formation method, is completely covered (the thickness of the thin film grown on the step portion is the same as the thickness of the thin film grown on the flat portion), that is, the step coverage is very high. Excellent. Therefore, steps due to structures on the substrate surface, minute defects on the substrate surface, particles adhering to the substrate surface, and the like can be completely covered, and such a step portion does not become an intrusion path for deterioration factors of the photoelectric conversion material. When the sealing layer 110 is formed by the atomic layer deposition method, the required sealing layer thickness can be reduced more effectively than in the prior art.

  In the case where the sealing layer 110 is formed by the atomic layer deposition method, a material corresponding to ceramics preferable for the sealing layer 110 described above can be appropriately selected. However, since the photoelectric conversion film of the present invention uses a photoelectric conversion material, it is limited to a material capable of growing a thin film at a relatively low temperature so that the photoelectric conversion material does not deteriorate. According to the atomic layer deposition method using alkyl aluminum or aluminum halide as a material, a dense aluminum oxide thin film can be formed at less than 200 ° C. at which the photoelectric conversion material does not deteriorate. In particular, when trimethylaluminum is used, an aluminum oxide thin film can be formed even at about 100 ° C. Silicon oxide and titanium oxide are also preferable because a dense thin film can be formed at less than 200 ° C., similarly to aluminum oxide, by appropriately selecting materials.

  The organic photoelectric conversion device and the imaging device of the present invention preferably contain a getter material in order to reduce the influence of moisture and / or oxygen. The getter material may be in the sealing layer. The getter material is optional as long as it can absorb moisture and / or oxygen. Examples of the material include alkali metal, alkaline earth metal, alkaline earth metal oxide, alkali metal or alkaline earth metal hydroxide, silica gel, zeolite compound, magnesium sulfate as a substance that absorbs moisture. And sulfates such as sodium sulfate and nickel sulfate, and organometallic compounds such as aluminum metal complexes and aluminum oxide octylates. Specifically, examples of the alkaline earth metal include Ca, Sr, and Ba. Examples of the alkaline earth metal oxide include CaO, SrO, and BaO. In addition, Zr-Al-BaO, an aluminum metal complex, etc. are also mentioned. Examples of the substance that absorbs oxygen include activated carbon, silica gel, activated alumina, molecular sieve, magnesium oxide, and iron oxide. In addition, Fe, Mn, Zn, Ti, and inorganic salts such as sulfates, chlorides, and nitrates of these metals are also included.

[Substituent W]
The substituent W is described.
As the substituent W, a halogen atom, an alkyl group (including a cycloalkyl group, a bicycloalkyl group, and a tricycloalkyl group), an alkenyl group (including a cycloalkenyl group and a bicycloalkenyl group), an alkynyl group, an aryl group, and a heterocyclic group (May be referred to as a heterocyclic group), cyano group, hydroxy group, nitro group, carboxy group, alkoxy group, aryloxy group, silyloxy group, heterocyclic oxy group, acyloxy group, carbamoyloxy group, alkoxycarbonyloxy group, Aryloxycarbonyloxy group, amino group (including anilino group), ammonio group, acylamino group, aminocarbonylamino group, alkoxycarbonylamino group, aryloxycarbonylamino group, sulfamoylamino group, alkyl and arylsulfonylamino group Mercapto group, alkylthio group, arylthio group, heterocyclic thio group, sulfamoyl group, sulfo group, alkyl and arylsulfinyl group, alkyl and arylsulfonyl group, acyl group, aryloxycarbonyl group, alkoxycarbonyl group, carbamoyl group, aryl and hetero Ring azo group, imide group, phosphino group, phosphinyl group, phosphinyloxy group, phosphinylamino group, phosphono group, silyl group, hydrazino group, ureido group, boronic acid group (-B (OH) ₂ ), phosphato Examples include a group (—OPO (OH) ₂ ), a sulfato group (—OSO ₃ H), and other known substituents.

More preferably, W represents the following (1) to (17).
(1) Halogen atom For example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom (2) an alkyl group represents a linear, branched, or cyclic alkyl group.
(2-a) alkyl group Preferably an alkyl group having 1 to 30 carbon atoms (for example, methyl, ethyl, n-propyl, isopropyl, t-butyl, n-octyl, eicosyl, 2-chloroethyl, 2-cyanoethyl, 2-ethylhexyl) )

(2-b) cycloalkyl group Preferably, the substituted or unsubstituted cycloalkyl group having 3 to 30 carbon atoms (for example, cyclohexyl, cyclopentyl, 4-n-dodecylcyclohexyl).

(3) Alkenyl group represents a linear, branched, or cyclic alkenyl group having 2 to 30 carbon atoms (eg, vinyl, allyl, styryl).

(4) Alkynyl group Preferably, the alkynyl group having 2 to 30 carbon atoms (for example, ethynyl, propargyl, trimethylsilylethynyl group)

(5) Aryl group Preferably, the aryl group has 6 to 30 carbon atoms (for example, phenyl, p-tolyl, naphthyl, m-chlorophenyl, o-hexadecanoylaminophenyl, ferrocenyl).

(6) Heterocyclic group Preferably, it is a monovalent group obtained by removing one hydrogen atom from a 5- or 6-membered aromatic or non-aromatic heterocyclic compound, more preferably 2 to 50 carbon atoms. It is a 5- or 6-membered aromatic heterocyclic group.
(For example, 2-furyl, 2-thienyl, 2-pyrimidinyl, 2-benzothiazolyl. In addition, a cationic heterocyclic group such as 1-methyl-2-pyridinio and 1-methyl-2-quinolinio may be used)

(7) Alkoxy group Preferably, the alkoxy group has 1 to 30 carbon atoms (for example, methoxy, ethoxy, isopropoxy, t-butoxy, n-octyloxy, 2-methoxyethoxy).

(8) Aryloxy group Preferably, the aryloxy group has 6 to 30 carbon atoms (for example, phenoxy, 2-methylphenoxy, 4-t-butylphenoxy, 3-nitrophenoxy, 2-tetradecanoylaminophenoxy).

(9) Amino group Preferably, an amino group, an alkylamino group having 1 to 30 carbon atoms, an anilino group having 6 to 30 carbon atoms (for example, amino, methylamino, dimethylamino, anilino, N-methyl-anilino, diphenylamino) )

(10) Alkylthio group Preferably, the alkylthio group has 1 to 30 carbon atoms (for example, methylthio, ethylthio, n-hexadecylthio).

(11) Arylthio group Preferably, arylthio having 6 to 30 carbon atoms (for example, phenylthio, p-chlorophenylthio, m-methoxyphenylthio)

(12) Heterocyclic thio group Preferably, the substituted or unsubstituted heterocyclic thio group having 2 to 30 carbon atoms (for example, 2-benzothiazolylthio, 1-phenyltetrazol-5-ylthio)

(13) Alkyl or arylsulfinyl group Preferably, it is a substituted or unsubstituted alkylsulfinyl group having 1 to 30 carbon atoms, a substituted or unsubstituted arylsulfinyl group having 6 to 30 carbon atoms (for example, methylsulfinyl, ethylsulfinyl, phenylsulfinyl, p-methylphenylsulfinyl)

(14) Alkyl or arylsulfonyl group, preferably an alkylsulfonyl group having 1 to 30 carbon atoms, an arylsulfonyl group having 6 to 30 carbon atoms, such as methylsulfonyl, ethylsulfonyl, phenylsulfonyl, p-methylphenylsulfonyl)

(15) Acyl group Preferably, a formyl group, an alkylcarbonyl group having 2 to 30 carbon atoms, an arylcarbonyl group having 7 to 30 carbon atoms, or a heterocyclic carbonyl bonded to a carbonyl group at 4 to 30 carbon atoms Groups (eg acetyl, pivaloyl, 2-chloroacetyl, stearoyl, benzoyl, pn-octyloxyphenylcarbonyl, 2-pyridylcarbonyl, 2-furylcarbonyl)

(16) Phosphino group Preferably, the phosphino group having 2 to 30 carbon atoms (for example, dimethylphosphino, diphenylphosphino, methylphenoxyphosphino).

(17) Silyl group Preferably, the silyl group having 3 to 30 carbon atoms (for example, trimethylsilyl, triethylsilyl, triisopropylsilyl, t-butyldimethylsilyl, phenyldimethylsilyl)

[Ring R]
Examples of the ring R include an aromatic or non-aromatic hydrocarbon ring, a heterocyclic ring, and a polycyclic fused ring formed by further combining these. For example, benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, fluorene ring, triphenylene ring, naphthacene ring, biphenyl ring, pyrrole ring, furan ring, thiophene ring, imidazole ring, oxazole ring, thiazole ring, pyridine ring, pyrazine ring, Pyrimidine ring, pyridazine ring, indolizine ring, indole ring, benzofuran ring, benzothiophene ring, isobenzofuran ring, quinolidine ring, quinoline ring, phthalazine ring, naphthyridine ring, quinoxaline ring, quinoxazoline ring, isoquinoline ring, carbazole ring, phenant Examples include a lysine ring, an acridine ring, a phenanthroline ring, a thianthrene ring, a chromene ring, a xanthene ring, a phenoxathiin ring, a phenothiazine ring, and a phenazine ring.

[Synthesis example of each compound]
(Synthesis Example 1)
The synthesis method of a compound (c-3) is shown. 0.47 g of sodium t-butoxy, 20 ml of xylene, 57 mg of palladium acetate and 0.18 g of tri (t-butyl) phosphonium hexafluoroborate were heated and stirred at 65 ° C. for 20 minutes under nitrogen, and 2,7-dibromo-9,9 ′ -0.6 g of spirobi [9H-fluorene] and 0.58 g of 9,9-dimethyl-9H-acridine were added, and the mixture was heated and stirred at 105 ° C for 2 hours under nitrogen. After cooling to room temperature, 40 ml of methanol was added, and the resulting solid was filtered and washed with acetonitrile, water, acetone and isopropanol to obtain 0.6 g of compound (c-3).

(Synthesis Example 2)
The synthesis method of a compound (c-13) is shown. 2,2 ′, 7,7′-Tetrabromo-9,9′-spirobi [9H-fluorene] 1.0 g, 1.7 g tribenzoazepine, 0.73 g sodium t-butoxy, 30 ml xylene, Pd [P (t -Bu) ₃ ] ₂ 0.12 g was heated at 95 <0> C for 6 hours under nitrogen. After cooling to room temperature, 30 ml of methanol was added, and the resulting solid was filtered and washed with acetonitrile, water, N, N-dimethylacetamide and isopropanol to obtain 1.8 g of compound (c-13).

(Synthesis Example 3)
Compound (c-23) was synthesized in the same manner as in Synthesis Example 2 except that tribenzazepine was changed to 7H-dibenzo [a, g] carbazole.

The obtained synthetic compound was purified by sublimation or distillation using ULVAC-RIKO TRS-160 as necessary. The degree of vacuum at this time was set to 0.07 Pa.
Structural formulas obtained in the above synthesis examples are shown below.

[Example 1]
A photoelectric conversion element having the form shown in FIG. That is, after forming a film of amorphous ITO 30 nm on a glass substrate by sputtering, a lower electrode is formed, and a compound (c-3) is formed on the lower electrode by a vacuum heating evaporation method using a mask, and electron blocking is performed. A layer was formed. Furthermore, the temperature of the substrate was controlled to 25 ° C. by vacuum heating deposition of a layer in which compound (1) and fullerene (C ₆₀ ) were co-deposited so as to be 100 nm and 300 nm in terms of a single layer, respectively, using a mask. A photoelectric conversion layer was formed by forming a film in this state. Note that the vacuum evaporation of the photoelectric conversion layer was performed at a vacuum degree of 4 × 10 ⁻⁴ Pa or less.
Further thereon, a transparent conductive film was formed by forming an amorphous ITO film having a thickness of 10 nm using a mask as an upper electrode by a sputtering method, and a photoelectric conversion element was produced.
Compound (1) is shown below. Compound (1) can be synthesized with reference to JP-A No. 2000-297068.

[Examples 2 and 3, Comparative Examples 1 to 3]
A photoelectric conversion element was produced in the same manner as in Example 1, except that the compound (c-3) used in the electron blocking layer was changed as shown in Table 1.

[Evaluation]
It was confirmed whether or not the photoelectric conversion element functions for each of the obtained elements. When a voltage is applied so that the electric field strength is 2.5 × 10 ⁵ V / cm with the electrode 11 in FIG. Although a dark current of 100 nA / cm ² or less was shown in the place, a current of 10 μA / cm ² or more was shown in the bright place, and it was confirmed that the photoelectric conversion element functions.
Table 1 shows the dark current value (relative value) of each element obtained and the increase of the dark current measured after holding each element in an environment of 175 ° C. for 30 minutes and returning to room temperature with respect to the dark current before heating. Indicates the magnification. In addition, Ip of each material was calculated | required by measuring each single layer film | membrane which formed each material each by AC-2 by Riken Keiki, and Ea was calculated | required by subtracting the energy for an energy gap from Ip. As the energy corresponding to the energy gap, a value obtained by converting the wavelength of the long wave end of the spectral absorption spectrum of the single layer film into energy was used.

  The compounds used in the comparative examples are shown below.

  In Examples 1 to 3, it can be seen that the increase in dark current after heating is smaller than that of Comparative Examples 1 to 3, and the heat resistance is high. In particular, in Examples 2 and 3, the dark current after heating hardly changes (magnification 1 to 2), and it can be seen that it is particularly excellent.

  Further, an image sensor similar to the embodiment shown in FIG. 2 was produced. That is, after depositing amorphous ITO 30 nm on a CMOS substrate by sputtering, patterning is performed so that one pixel exists on each photodiode (PD) on the CMOS substrate by photolithography to form a lower electrode. The film formation after the electron blocking material was made in the same manner as in Examples 1 to 3 and Comparative Examples 1 to 3. The evaluation was carried out in the same manner, and the same results as in Table 1 were obtained. In the image pickup device, the device based on the example of the present invention showed a low dark current after heating and high heat resistance.

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

Claims (22)

A photoelectric conversion element having a transparent conductive film, a photoelectric conversion film, and a conductive film in this order,
The photoelectric conversion film includes a photoelectric conversion layer and an electron blocking layer,
The electron blocking layer contains a compound represented by the following general formula (F-3),
The photoelectric conversion element whose compound represented by the said general formula (F-3) is a compound which has a substituted amino group containing three or more ring structures as a substituent.
Formula (F-3)

(In General Formula (F-3), each R ₃₁ independently represents a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a hydroxyl group, an amino group, or a mercapto group, and these further have a substituent. R ₃₂ , R ₃₇ , R ′ ₃₂ , and R ′ ₃₇ each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a hydroxyl group, an amino group, or a mercapto group. These may further have a substituent, provided that at least one of R ₃₂ , R ′ ₃₂ , R ₃₇ and R ′ ₃₇ represents a substituted amino group containing three or more ring structures. each If .R ₃₁ representing an integer of independently 0-3 is more present in said general formula (F-3), a plurality of R ₃₁ may be different from each other.) 2. The photoelectric device according to claim 1, wherein, in the general formula (F-3), R ₃₂ and R ₃₇ represent a substituted amino group containing three or more ring structures, and R ′ ₃₂ and R ′ ₃₇ represent a hydrogen atom. Conversion element.   The photoelectric conversion element of Claim 1 or 2 whose m3 is 0 in the said general formula (F-3). The photoelectric conversion element according to claim 1, wherein, in the general formula (F-3), R ₃₂ , R ₃₇ , R ′ ₃₂ and R ′ ₃₇ represent a substituted amino group containing three or more ring structures. The photoelectric conversion element of any one of Claims 1-4 whose substituted amino group containing 3 or more of the said ring structures is group represented by the following general formula (A-1).
Formula (A-1)

(In the formula, Ra _{1 to} Ra ₈ each independently represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, or a heterocyclic group, and these may further have a substituent. * Represents a bonding position. Xa represents a single bond, an oxygen atom, a sulfur atom, an alkylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, a divalent heterocyclic group, or an imino group, and these further represent a substituent. May be included.)   The photoelectric conversion element according to claim 5, wherein Xa in the general formula (A-1) is a single bond, an alkylene group, an alkenylene group, an arylene group, a heterocyclic group, an oxygen atom, a sulfur atom, or an imino group. The photoelectric conversion element of any one of Claims 1-4 whose substituted amino group containing 3 or more of the said ring structures is group represented by the following general formula (A-2).
General formula (A-2): -N (R _B1 ) (R _B2 )
(R _B1 and R _B2 each independently represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, or a heterocyclic group, and these may further have a substituent, provided that R _B1 and R _B2 At least one represents an aryl group or a heterocyclic group, and the total number of rings contained in R _B1 and R _B2 is 3 or more.) The photoelectric conversion element according to claim 7, wherein at least one of R _B1 and R _B2 is a group represented by the following general formula (b-1).
Formula (b-1)

(In the formula, each Rb independently represents a halogen atom, an alkyl group, an aryl group, or a heterocyclic group, and these may further have a substituent. Xb each independently represents a single bond, oxygen, An atom, a sulfur atom, an alkylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, a divalent heterocyclic group, or an imino group, which may further have a substituent, and Rb is plural. When present, they may be the same or different from each other, two Xb's in the formula may be the same or different from each other, * represents a bonding position, m4 represents an integer of 0 to 3, and m5 represents 0 to 0 Represents an integer of 4.) A substituted amino group containing three or more ring structures is a group represented by the following general formula (A-3), a group represented by the following general formula (A-4), or the following general formula (A-5). The photoelectric conversion element of any one of Claims 1-4 which is group represented.

(In the general formulas (A-3) to (A-5), Ra _{33 to} Ra ₃₈ , Ra ₄₁ , Ra _{44 to} Ra ₄₈ , Ra ₅₁ , Ra ₅₂ , Ra _{55 to} Ra ₅₈ are each independently a hydrogen atom. , A halogen atom, or an alkyl group, which may further have a substituent, * represents a bonding position, Xc ₁ , Xc ₂ , and Xc ₃ are each independently a single bond, an oxygen atom, Z ₃₁ represents a sulfur atom, an alkylene group, a silylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, an arylene group, a divalent heterocyclic group, or an imino group, and these may further have a substituent. , Z ₄₁ , and Z ₅₁ each independently represents a cycloalkyl ring, an aromatic hydrocarbon ring, or an aromatic heterocyclic ring, which may further have a substituent.   The photoelectric conversion element of any one of Claims 1-9 whose ionization potential (Ip) of the compound represented by the said general formula (F-3) is 5.8 eV or less.   The photoelectric conversion element of any one of Claims 1-10 whose ionization potential (Ip) of the compound represented by the said general formula (F-3) is 4.9 eV or more.   The photoelectric conversion element of any one of Claims 1-11 whose molecular weight of the compound represented by the said general formula (F-3) is 500-2000.   The photoelectric conversion element of any one of Claims 1-12 in which the said photoelectric converting layer contains an n-type organic semiconductor.   The photoelectric conversion element according to claim 13, wherein the n-type organic semiconductor is fullerene or a fullerene derivative. The photoelectric conversion element of any one of Claims 1-14 in which the said photoelectric conversion film contains the compound of the following general formula (I).
Formula (I)

(In the formula, Z ₁ represents an atomic group necessary for forming a 5- or 6-membered ring. L ₁ , L ₂ , and L ₃ each independently represent an unsubstituted methine group or a substituted methine group. D ₁ represents an atomic group, and n1 represents an integer of 0 or more.)   The photoelectric conversion element of any one of Claims 1-15 by which the electroconductive film, the electron blocking layer, the photoelectric converting layer, and the transparent conductive film were laminated | stacked in this order.   It is a manufacturing method of the photoelectric conversion element of any one of Claims 1-15, Comprising: The manufacturing method including the process of forming into a film the said photoelectric converting layer and the said electronic blocking layer by vacuum heating vapor deposition, respectively.   The optical sensor which consists of a photoelectric conversion element of any one of Claims 1-15.   The image pick-up element provided with the photoelectric conversion element of any one of Claims 1-15.   The photoelectric conversion element according to claim 1, the optical sensor according to claim 18, or the image sensor driving method according to claim 19, wherein the electrode is in contact with the electron blocking layer. A driving method in which a cathode is used as a cathode and the other electrode is used as an anode, and a voltage higher than 0V and lower than 100V is applied.   The electron blocking material which consists of a compound represented by general formula (F-3) of Claim 1.   A film having a thickness of 1 to 1000 nm containing the compound represented by formula (F-3) according to claim 1.

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