KR101869620B1 - Method for forming light receiving layer, method for producing organic photoelectric conversion element, organic material for film formation, organic photoelectric conversion element obtained using same, and photosensor - Google Patents

Abstract

A method for forming a light-receiving layer capable of stably producing an organic photoelectric conversion device having excellent afterimage current characteristics, a method for manufacturing an organic photoelectric conversion element, an organic material for film formation, and an organic photoelectric conversion element and an optical sensor obtained using the same.
A method of forming a light receiving layer (30) for forming a light receiving layer (30) of an organic photoelectric conversion element (1) used in an optical sensor by dry film formation, characterized by comprising the steps of: (60) is prepared, and dry film formation is performed using a source of light including the organic material for film formation (60).

Description

TECHNICAL FIELD [0001] The present invention relates to a method of forming a light-receiving layer, a method of manufacturing an organic photoelectric conversion device, an organic material for film formation, and an organic photoelectric conversion device and an optical sensor obtained therefrom using an organic photoelectric conversion device and an optical sensor. , ORGANIC PHOTOELECTRIC CONVERSION ELEMENT OBTAINED USING SAME, AND PHOTOSENSOR}

The present invention relates to a method of forming a light-receiving layer of an organic photoelectric conversion element by dry film formation, and a method of manufacturing an organic photoelectric conversion element using the same. The present invention also relates to an organic material for film formation used for dry film formation of a light receiving layer of an organic photoelectric conversion element, and an organic photoelectric conversion element and an optical sensor obtained using the same.

2. Description of the Related Art As image sensors used in digital cameras, cameras for mobile phones, cameras for endoscopes, etc., imaging devices such as CCD sensors and CMOS sensors are widely known. These elements are provided with a photoelectric conversion element having a light receiving layer including a photoelectric conversion layer between a pair of electrodes. The photoelectric conversion element is an element that generates charge in the photoelectric conversion layer in accordance with light incident from the transparent electrode side having light transparency among a pair of electrodes and reads out the generated charge as a signal charge from the electrode.

Application of organic photoelectric conversion elements having excellent characteristics such as weight reduction, large area, high flexibility, and manufacturing process by a printing process has been proposed by applicants. Photoelectric conversion elements used in image pickup devices are required to satisfy a high level in various performances such as S / N ratio of photocurrent / dark current, response speed, and residual image current.

The present applicant has proposed a mixed layer (bulk hetero layer) of a p-type organic semiconductor and an n-type semiconductor such as a fullerene or fullerene derivative as an organic photoelectric conversion layer in which good photoelectric conversion efficiency can be obtained in the organic photoelectric conversion element Patent Documents 1 to 2, etc.).

The bulk hetero layer can be produced, for example, by co-deposition (vacuum deposition) of a p-type organic semiconductor material and an n-type organic semiconductor material. In the co-deposition, a plurality of evaporation sources are arranged and the velocity and the like are controlled to form a film of the desired composition.

According to Patent Document 1, it is possible to provide an organic photoelectric conversion element having high photoelectric conversion efficiency and good S / N ratio of photocurrent / dark current. Further, in Patent Document 2, a sufficient sensitivity and heat resistance can be obtained by providing a mixed layer on at least one of the electron blocking layers, and high-speed responsiveness can be realized.

Patent Document 1: JP-A-2007-123707 Patent Document 2: JP-A-2012-94660

One of the performances required in the photoelectric conversion element used in the image pickup device described above is a low residual image current. The residual image current is evaluated as a ratio of a current to a current at the time of light incidence after a certain period of time since light was turned off. At present, residual image current required as an image pickup element is required to be 0.1%, preferably 0.01%, in proportion to a current of 0.1 second after turning off light for a current at the time of incidence of light.

The approach toward the low-residual current can be attempted in various aspects such as the constituent material of the light-receiving layer, the layer configuration, the configuration of the image pickup device, etc. However, even when these configurations are made the same, There is a pressing need for clarification of the cause.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances and provides a method of forming a light receiving layer capable of stably producing an organic photoelectric conversion element having a small residual current in a method of forming a light receiving layer of an organic photoelectric conversion element for use in an optical sensor It is aimed at.

In the light-receiving layer forming method of the present invention,

A light-receiving layer forming method for forming a light-receiving layer of an organic photoelectric conversion element used for an optical sensor by dry film formation,

At least one organic material for film formation comprising a constituent organic substance of the light-receiving layer and a powder having a fluorescence quantum yield of 0.2 or more is prepared,

And dry film formation is performed using a vaporizing source made of the organic film-forming organic material.

The organic material for film formation of the present invention is used for dry film formation of the light receiving layer of the organic photoelectric conversion element,

And a powder having a fluorescence quantum yield of not less than 0.2 which is composed of an organics constituting the light-receiving layer.

In the present specification, the expression "consisting of A" means not including A and unavoidable impurities. For example, "a source of ignition made of an organic material for film formation" means a source of ignition that does not include any organic material for film formation and inevitable impurities.

In the present specification, the term "constituent organic material" means all organic materials other than substances which are unavoidably included in the inevitable impurities and organic materials for film formation, among the organic materials contained in the organic material for film formation.

In this specification, the fluorescence quantum yield means the absolute fluorescence quantum yield. Note that the dry film formation in this specification does not include a chemical vapor deposition method.

It is preferable that the yield of fluorescent quantum of the particulate material composed of the constituent organic substance of the light receiving layer is 0.2 or more and 0.4 or less. The constituent organic material is preferably a p-type organic semiconductor material, and preferably has at least one amine moiety of the following formula (A) or a carbonyl group moiety of the following formula (B).

[Chemical Formula 1]

(Wherein ^{(A), R 30 ~ R} 31 are, each independently, an alkyl group which may have a substituent, represents a heteroaryl group which may have an aryl group or a substituent which may have a substituent. R ³² is a substituent Or a heteroarylene linking group which may have a substituent, R ³⁰ to R ³² may be connected to each other to form a ring.

(2)

(In the formula (B), Y ₁ represents a condensed ring containing at least any one of a 5-membered ring, a 6-membered ring, or a 5-membered ring and a 6-membered ring containing two or more carbon atoms, The substituents may be bonded to each other to form a ring as far as possible.)

As the constituent organic material, a p-type organic semiconductor material represented by the following formula (C) is more preferable.

(3)

(Wherein (C) of, Z ₄ represents a condensed ring containing at least two a ring containing carbon atoms and 5-membered ring, 6-membered ring, or at least one of a 5-membered ring and a 6-membered ring. L _1, L ₂ , And L < ₃ > each independently represent an unsubstituted methoxy group or a substituted methoxy group, and D < ₁ >

The dry film formation method is preferably a resistance heating deposition method. The light-receiving layer is preferably a photoelectric conversion layer.

A manufacturing method of an organic photoelectric conversion element of the present invention is a manufacturing method of an organic photoelectric conversion element having a pair of electrodes and a light receiving layer including at least a photoelectric conversion layer sandwiched between the pair of electrodes, Layer forming method.

The organic photoelectric conversion element of the present invention is an organic photoelectric conversion element having a pair of electrodes and a light receiving layer containing at least a photoelectric conversion layer sandwiched between the pair of electrodes and the light receiving layer is formed by using the above- And is formed by dry deposition.

The optical sensor of the present invention includes a plurality of the organic photoelectric conversion elements of the present invention and a circuit board on which a signal readout circuit for reading out a signal corresponding to the charge generated in the photoelectric conversion layer of the photoelectric conversion element is formed, And is suitable as an imaging device.

In the present invention, the light-receiving layer of the organic photoelectric conversion element used in the photosensor is dry-formed by using a particulate material having a fluorescence quantum yield of 0.2 or more, which is made of an organics constituting the light- By forming a light-receiving layer using a source including such a powder, it is possible to stably manufacture an organic photoelectric conversion element having a low residual current. According to the present invention, it is possible to select a material of a source of fire suitable for dry film formation of the light-receiving layer by a simple method of measuring the value of the fluorescent quantum yield of the powder, Can be easily and low-cost predicted by measuring the fluorescence quantum yield of a powder sample of a source material without preparing a photoelectric conversion element.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic structural cross-sectional schematic diagram showing an embodiment of an organic photoelectric conversion element of the present invention. FIG.
2 is a schematic perspective view (vacuum heating deposition) showing a deposition method of the light-receiving layer.
3 is a schematic structural cross-sectional schematic diagram showing an embodiment of an image pickup device of the present invention.
Fig. 4 is a graph showing the relationship between the residual current value of the organic photoelectric conversion element of the examples and the comparative example and the fluorescence quantum yield of the organic material for film formation in the light-receiving layer. Fig.

"Organic material for film formation, method of forming light-receiving layer, photoelectric conversion element"

A photoelectric conversion element according to an embodiment of the present invention will be described with reference to the drawings. 1 is a schematic cross-sectional view showing a structure of a photoelectric conversion element of the present embodiment. In the drawings of the present specification, the scale of each part is appropriately changed for easy visibility.

1, the organic photoelectric conversion element 1 (photoelectric conversion element 1) includes a substrate 10, a pair of electrodes (a lower electrode 20 and an upper electrode 20) formed on the substrate 10, (40), a light receiving layer (30) sandwiched therebetween, and a sealing layer (50) formed on the upper electrode (40).

The light receiving layer 30 may be a layer containing at least the photoelectric conversion layer 32. In this embodiment, the electron blocking layer 31 is provided between the lower electrode 20 and the photoelectric conversion layer 32 have. The light receiving layer 30 may be a layer including a layer other than the photoelectric conversion layer 32 and the electron blocking layer 31 (for example, a hole blocking layer).

The electromagnetic blocking layer 31 included in the light receiving layer 30 suppresses the injection of electrons from the lower electrode 20 (hereinafter referred to as the electrode 20) into the photoelectric conversion layer 32, 32 from flowing to the electrode 20 side. The electron blocking layer 31 is composed of an organic material or an inorganic material, or both.

The upper electrode 40 (hereinafter referred to as an electrode 40) is an electrode that collects electrons in the charge generated in the photoelectric conversion layer 32. The upper electrode 40 uses a conductive material (for example, ITO) that is sufficiently transparent to the light having the wavelength of the sensitivity of the photoelectric conversion layer 32 so that light is incident on the photoelectric conversion layer 32. By applying a bias voltage between the electrode 40 and the electrode 20, it is possible to move the holes in the charge generated in the photoelectric conversion layer 32 to the electrode 20 and electrons to the electrode 40.

When the light is incident from above the electrode 40, the light is transmitted through the electrode 40 to form the photoelectric conversion layer (photoelectric conversion layer) 32, where charges are generated. The holes in the generated charge move to the electrode 20. The light that has moved to the electrode 20 is converted into a voltage signal in accordance with the amount of the voltage and read out, thereby converting the light into a voltage signal and extracting it.

Alternatively, a bias voltage may be applied so as to trap electrons in the electrode 20 and trap the holes in the electrode 40. [ In this case, a hole blocking layer may be provided instead of the electron blocking layer 31. The hole blocking layer is formed of an organic material for inhibiting the injection of holes from the electrode 20 into the photoelectric conversion layer 32 and preventing the holes generated in the photoelectric conversion layer 32 from flowing to the electrode 20 side Layer. In any case, the portion sandwiched between the electrode 20 and the electrode 40 becomes the light-receiving layer 30.

It has been confirmed that the residual image current value of the image pickup device is non-uniform even when the light-receiving layer material, the layer configuration, the configuration of the image pickup device, and the like are made the same as described in the item "Challenge to solve". As described in Patent Documents 1 and 2, a dry film forming method using an organic material 60 for film formation, which is an organic substance constituting the light-receiving layer, is preferably used for film formation of the light-receiving layer of the organic photoelectric conversion element. In the dry film formation, film formation is performed using a film forming material containing a constituent material such as an evaporation source or a sputtering target as a source of fire.

Therefore, the present inventors paid attention to the material of the source of light used for forming the light-receiving layer, and carefully examined the relationship between the physical properties of the source and the residual image current. As a result, it was found that there was a characteristic correlation between the afterglow current and the fluorescence quantum yield in the case of the organic material for film formation contained in the light-receiving layer source.

The fluorescence quantum yield is a value expressed as a ratio of the number of emitted photons to the number of photons absorbed in the material, and the closer the fluorescence quantum yield is to 1, the better the efficiency of fluorescence emission. Fluorescence quantum yield does not become 1 due to transition to another excited state from the excited state to the base state, thermal inactivation, reabsorption, and extinction with trace impurities. The inventor of the present invention has found that by using the organic film forming organic material 60 included in the light source of the light-receiving layer 30 having a fluorescence quantum yield of 0.2 or more at the time of granulation, it is possible to obtain a high- It was found that the organic photoelectric conversion device can be manufactured and the residual current characteristics were remarkably improved with 0.2 as a boundary (see the following examples and comparative examples, see Fig. 4). This is thought to be the influence of the amount of light emitted by the difference in the amount of trace impurities, which is usually difficult to detect, and the fluorescence quantum yield is fluctuated.

That is, the organic photoelectric conversion element 1 is formed by dry film formation using an organic material 60 for film formation, which is composed of a particulate material having a fluorescence quantum yield of 0.2 or more, the light-receiving layer 30 being composed of organics constituting the light- will be.

As described above, the higher the fluorescent quantum yield of the film forming organic material 60 is, the more desirable it is. Therefore, if the lower limit value is 0.2 or more, the low persistence current value can be maintained. In the following example, as shown in Fig. 4, it was confirmed that the residual image current value was achieved by measuring the residual image current value until the fluorescence quantum yield was 0.395 (0.4 or less).

As the film forming organic material 60, an organic material for high purity film formation is usually used in an HPLC (high performance liquid chromatography) purity of 95% or more, preferably 98% or more. The inventors of the present invention presume that a minute amount of a substance for extinguishing fluorescence exists in the powdered organic material for film formation and that the content of the substance is uneven in the conventionally used organic material for high purity film formation, It is believed that the organic photovoltaic device with excellent afterimage current characteristics can be stably produced by suppressing the incorporation of a substance that extinguishes fluorescence by removing the extinction substance, that is, by setting the fluorescence quantum yield to 0.2 or more.

The method of making the fluorescent quantum yield of the organic material 60 for forming a separation film to be 0.2 or more (hereinafter, referred to as a fluorescence quenching material removing step) is a method in which, for example, decomposition of a material is promoted at the time of melting an organic material for high- , And the filtrate is subjected to suction filtration with a membrane filter having a pore diameter of 0.1 mu m to 1 mu m to remove the solvent by concentration under reduced pressure. In addition to the above, it is also possible to use other methods such as sublimation purification, recrystallization purification, column chromatography purification, reslurry (dispersion in a solvent), vacuum drying, reprecipitation purification, separation, water, washing with a solvent, filtration, , Diatomaceous earth, ion exchange resin, resin, inorganic porous (zeolite), air drying, heat drying method, and freeze drying. By repeating these methods or combining a plurality of methods, it is possible to gradually increase the fluorescent quantum yield of the organic material 60 for film formation.

In the case of synthesizing an organic material for film formation, the fluorescence extinction substance removing method may be carried out after the ordinary purification step of the synthesized organic material.

At present, as a dry film forming material of an organic photoelectric conversion element, an organic material for high purity film formation having an HPLC purity of 99% or more is generally used. There is no report on the use after the above-mentioned process of removing the fluorescent quencher. As described in the following examples and comparative examples, the fluorescence quantum yield is surely changed by performing the fluorescent quencher removing step, that is, the substance is different in the physical property values as the powder compact (comparative example is a conventional And an organic material for film formation, which has been subjected to a purification step for forming an organic material for high purity film formation). This indicates that the organic film forming organic material 60 itself having a fluorescence quantum yield of 0.2 or more is a novel substance.

The light-receiving layer 30 to be formed using the film forming organic material 60 may be a photoelectric conversion layer 32, an electron blocking layer 31 or a hole blocking layer (not shown), but the photoelectric conversion layer 32).

The organic material constituting the light-receiving layer 30 includes a p-type organic semiconductor material and an n-type organic semiconductor material. The film formation using the organic film forming organic material 60 of the present embodiment as the p- desirable. Materials suitable for the p-type organic semiconductor material and the n-type organic semiconductor material, the electron blocking layer, the hole blocking layer, etc. constituting the light-receiving layer 30 will be described below.

The particle size of the film forming organic material 60 made of the powder is not particularly limited, but it is preferable that the average particle size is 50 μm or more and 800 μm or less. In the present specification, the average particle diameter means an average particle diameter expressed by D50%. The "average particle diameter expressed by D50%" is the particle diameter when the larger particle and the smaller particle become equal to each other when dividing the plurality of particles from the predetermined particle diameter by two. In the present invention, the average particle diameter represented by D50% is determined by reading the percentage of passage or 50% of the cumulative percentage from the particle size curve. The particle size curve is not particularly limited, but a method of sieving a sample, examining how many percent of a mesh a few microns of the sample has passed at a weight percentage of the sample, plotting the sieve diameter on the abscissa and the percentage passing on the ordinate And a method of performing cumulative distribution measurement using a laser diffraction particle size analyzer. In the case where the powder is pulverized by pulverization or the like and the average particle size is significantly reduced to less than 20 占 퐉, in addition to the extinction by the trace impurities, suppression of reabsorption due to refinement of the pulverulent material, , There is a possibility that the value of the fluorescence quantum yield changes.

It is preferable that the bulk density of the film-forming organic material 60 made of the powder is 0.3 g / mL or more. Bulk density refers to a sparse filled bulk density, which is a value obtained by compacting a powder into a volume-measurable container and dividing the mass of the powder by the volume of the powder including the void volume between the particles. Specifically, a powder sample is placed in a measuring container carefully by using a volumetric meter or the like and sieved through a sieve having a sieve of 1 mm by calculation from the mass and volume of the powder in the container so as not to change the properties of the sample.

In addition, the organic material for high purity film formation may contain a residual solvent that can not be detected by HPLC. It is preferable that this solvent is subjected to a solvent removal step in which the residual solvent is adjusted to 3 mol% or less from the viewpoint of affecting characteristics such as photoelectric conversion efficiency, S / N ratio of photocurrent / dark current, and response speed.

Regarding the kind of the residual solvent, the influence amount is not limited, but the kind is not limited. Examples of the solvent include water, alcohols, ethers, ketones, sulfoxides, carbonates, amides, carboxylic acids, esters, nitriles, halogens and aromatics. More specifically, when two or more kinds of solvents are contained, it is preferable that the total content of two or more kinds is 3 mol% or less.

Specific examples of the solvent that may possibly remain include alcohols such as methanol, ethanol, propanol, isopropanol, butanol, isobutanol, t-butyl alcohol, ethylene glycol, propylene glycol, glycerin, (Ethylene oxide), ethylene oxide, polypropylene oxide, anisole, diphenyl ether, THF (tetrahydrofuran), ethylene glycol, Dioxolane, 1,3-dioxolane, acetone, MEK (methyl ethyl ketone), cyclohexanone, cyclopentanone, dimethylsulfoxide, dimethylsulfone, sulfolane, dimethylcarbonate, diethylcarbonate, ethylene Propylene carbonate, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, N-ethylpyrrolidone, acetic acid, ethyl acetate, acetonitrile M-, p-xylene, toluene, o-, m-, p-TMB (trimethylbenzene), chlorobenzene, o-, m-, p- dichlorobenzene , Nitrobenzene, chloroform, methylene chloride and the like, but it is not limited to the above solvent.

The removal of the residual solvent can be carried out by a conventional method such as sublimation purification, recrystallization purification, column chromatography purification, reslurry (dispersion in solvent), vacuum drying, reprecipitation purification, separation, water, solvent washing, Adsorption with graphite, activated carbon, diatomaceous earth, ion exchange resin, resin, inorganic porous (zeolite), air drying, heat drying method and freeze drying.

In addition, as a commercially available organic material for high purity film formation, it is not often that the metal content is 10 ppm or less. Therefore, when an organic material for film formation is commercially available, it is preferable to perform a metal removing step so that the metal content of the commercially available film-forming organic material is less than 10 ppm. It is preferable that the film forming organic material 60 does not particularly contain metals such as Al, Fe, Cu, Zn, Zr, Ca, Mg, Cr, Ni, Mo, Mn, Na, Si, B, Further, it is preferable that no halogen element such as F, Cl, Br or I is included. It is more preferable that the content of the halogen element is less than 100 ppm. It is preferable that the solvent removing step and the metal removing step are carried out before or at the time of performing the fluorescence quenched material removing step.

The film forming organic material 60 is composed of the organic material of the light receiving layer 30 (for example, the photoelectric conversion layer 32) and is composed of a particulate material having a fluorescence quantum yield of 0.2 or more. Therefore, , The powder may be used as it is, or it may be used in the form of a target. The molding method for the target is not particularly limited, and examples thereof include a solidification molding sintering method, a hot pressing method, a hot isostatic pressing method, and a hot extrusion method.

The dry film formation of the light-receiving layer material of the organic photoelectric conversion element is mainly performed by a physical vapor deposition method. Examples of physical vapor deposition methods include resistance heating deposition, sputtering, electron beam deposition, ion plating, molecular beam epitaxy, ion beam deposition, and pulse laser deposition. These dry film forming methods differ in the manner of the source of the fire according to the film forming method. For example, a resistance heating deposition, an electron beam deposition, or the like uses powder or solid matter of a constituent organic substance to be deposited as it is as a source of vapor. In the case of the sputtering method and the pulse laser deposition method, a target material of a flat or cylindrical bulk shape is used as the source of the fire. As a dry film forming method, a method which can use the organic film forming organic material 60 as a source of light is preferable, and a resistance heating deposition method is more preferable.

Fig. 2 shows an example of a schematic diagram showing a deposition state of resistance heating deposition. 2, deposition of the light-receiving layer is performed by providing a substrate holder 90 above the opening of the evaporation cell 71 provided in the evaporation chamber 91, B) is installed. (Deposition material) 60 is provided in the deposition cell 71 having a heating function and the inside of the deposition chamber 91 has a high degree of vacuum. Therefore, the evaporation material evaporated from the deposition cell 71 Is emitted from the opening and straightened, and is formed on the substrate (B). By adjusting the opening diameter of the opening of the evaporation cell 71, the maximum emission angle? Of the evaporated evaporation material can be adjusted.

Preferably, the deposition cell 71 and the substrate B are spaced apart by at least 10 cm. The vaporized evaporation material is spread in a substantially conical shape at an incident angle of 0 DEG to &thetas; with respect to the substrate surface.

The film-forming organic material 60 is provided as an evaporation source in the form of a boat, a basket, a hairpin, a crucible, or the like, and is not particularly limited.

When the film is formed by the resistance heating deposition method, the deposition rate is preferably 0.2 to 12 占 퐏 / s from the viewpoint of productivity. The film-forming temperature may be a temperature falling within the range of the deposition rate (deposition rate), and is preferably in the range of 150 to 750 ° C.

In the embodiment described below, since the organic material 60 for film formation is used for the photoelectric conversion layer 32 constituting the light-receiving layer 30, But the present invention can be suitably applied to the electron blocking layer 31 and a hole blocking layer (not shown).

The film-forming organic material 60 is composed mainly of organic substances constituting the light-receiving layer 30 of the organic photoelectric conversion element 1 used in the optical sensor.

Hereinafter, the structure of the photoelectric conversion element 1 shown in Fig. 1 will be described. As described above, by the dry film forming method using the above-mentioned organic film forming material 60, the light receiving layer 30 (e.g., the photoelectric conversion layer 32 and the electron blocking layer 31) ), It is possible to stably manufacture the organic photoelectric conversion element 1 with a small residual current.

<Substrate and Electrode>

The substrate 10 is not particularly limited, and a silicon substrate, a glass substrate, or the like can be used.

The lower electrode 20 is an electrode for collecting holes in the charge generated in the photoelectric conversion layer 32. The lower electrode 20 is not particularly limited as long as the conductivity is good. However, the lower electrode 20 may have transparency depending on the application, or may be made of a material that reflects light without providing transparency. Specific examples thereof include conductive metal oxides such as tin oxide (ATO, FTO) doped with antimony or fluorine, tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), zinc oxide indium (IZO) (Such as titanium nitride (TiN) as an example) such as oxides or nitrides of metals such as chromium, nickel, titanium, tungsten, aluminum and the like, and mixtures or laminates of these metals and conductive metal oxides, Organic conductive materials such as polyaniline, polythiophene, and polypyrrole; and a laminate of these materials and ITO or titanium nitride.

The upper electrode 40 is an electrode that collects electrons in the charge generated in the photoelectric conversion layer 32. The upper electrode 40 is not particularly limited as far as the photoelectric conversion layer 32 is a conductive material sufficiently transparent to the light having the sensitivity so as to allow light to enter the photoelectric conversion layer 32. [ Specific examples thereof include conductive metal oxides such as tin oxide (ATO, FTO) doped with antimony or fluorine, tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), zinc oxide indium (IZO) A metal thin film such as chromium, nickel and the like, a mixture or laminate of these metals and a conductive metal oxide, an inorganic conductive material such as copper iodide and copper sulfide, an organic conductive material such as polyaniline, polythiophene and polypyrrole, And a laminate of these and ITO. Of these, preferred are conductive metal oxides from the viewpoints of high conductivity and transparency.

The method for forming the electrode is not particularly limited and may be suitably selected in consideration of suitability with an electrode material. Specifically, it can be formed by a physical method such as a wet method such as a printing method or a coating method, a vacuum evaporation method, a sputtering method, and an ion plating method, or a chemical method such as CVD or plasma CVD.

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 deposition method, a chemical reaction method (sol-gel method), a dispersion of indium tin oxide or the like. In addition, UV-ozone treatment, plasma treatment, and the like can be performed on a film produced using ITO. When the material of the electrode is TiN, various methods including a reactive sputtering method are used, and UV-ozone treatment, plasma treatment, and the like can be performed.

It is preferable that the upper electrode 40 is formed by plasma-free because it is preferable that the upper electrode 40 is formed by a method that does not deteriorate the characteristics of the organic photoelectric conversion layer 32 in order to form the film on the organic photoelectric conversion layer 32. [ Here, the plasma free means that no plasma is generated during film formation of the upper electrode 40, or that the distance from the plasma generating source to the gas is not less than 2 cm, preferably not less than 10 cm, more preferably not less than 20 cm, Which means that the plasma is reduced.

As an apparatus in which no plasma is generated during film formation of the upper electrode 40, for example, there are an electron beam deposition apparatus (EB deposition apparatus) and a pulsed laser deposition apparatus. As for the EB evaporation apparatus or the pulsed laser deposition apparatus, the "new development of the transparent conductive film" (Yoshitaka Sawada, 1999) and Yasaka Sawada supervision "the new development of the transparent conductive film II" Quot; Technology of Transparent Conductive Film "(Ohmsha, 1999), and Provisional Reference Literature, etc. can be used. Hereinafter, a method of forming a transparent electrode film by using an EB evaporation apparatus is referred to as an EB evaporation method, and a method of forming a transparent electrode film by using a pulse laser evaporation apparatus is referred to as a pulse laser evaporation method.

(Hereinafter referred to as a plasma-free film formation apparatus) capable of realizing a state in which the distance from the plasma generating source to the gas is 2 cm or more and the arrival of the plasma to the gas is reduced (hereinafter referred to as a plasma pre- (1999), Yasaka Sawada supervised "New development of transparent conductive film II" (published by CMC, 2002), Japan Society for the Promotion of Science. , "Technology of Transparent Conductive Film" (OMO, 1999), and references cited therein.

When a transparent conductive film such as TCO (transparent conductive glass) is used as the upper electrode 40, a DC short or an increase in leakage current may occur. One of the causes is considered to be that a fine crack introduced into the photoelectric conversion layer 32 is covered by a dense film such as TCO and the conduction with the lower electrode 20 on the opposite side increases. As a result, in the case of an electrode having a relatively poor film quality such as Al, an increase in leakage current is unlikely to occur. By controlling the film thickness of the upper electrode 40 with respect to the film thickness of the photoelectric conversion layer 32 (that is, the depth of the crack), it is possible to greatly suppress the increase of the leak current. The thickness of the upper electrode 40 is preferably 1/5 or less, preferably 1/10 or less of the thickness of the photoelectric conversion layer 32.

In general, when the conductive film is made thinner than a predetermined range, an abrupt resistance value is increased. In the solid-state image pickup device incorporating the photoelectric conversion element according to the present embodiment, the sheet resistance is preferably 100 to 10000? /? The degree of freedom of the range of film thickness that can be made thin is large. Further, the thinner the thickness of the upper electrode 40, the smaller the amount of absorbed light, and the light transmittance generally increases. The increase of the light transmittance is highly preferable because it increases light absorption in the photoelectric conversion layer 32 and increases the photoelectric conversion ability. The film thickness of the upper electrode 40 is preferably 5 to 100 nm, more preferably 5 to 20 nm, in consideration of the suppression of leakage current, the increase in the resistance value of the thin film, and the increase in the transmittance.

A bias voltage is applied between the upper electrode 40 and the lower electrode 20 to move the holes generated in the photoelectric conversion layer 32 to the lower electrode 20 and electrons to the upper electrode 40 .

<Light-receiving layer>

The light receiving layer 30 is an organic layer including at least the photoelectric conversion layer 32 and includes an organic layer formed by the dry film forming method using the organic material 60 for film formation. In the present embodiment, the light-receiving layer 30 is constituted by the electron blocking layer 31 and the photoelectric conversion layer 32, and either or both of them are formed using the organic material for film formation 60, Film formation method. In order to further suppress the incorporation of the pixel defects and the unevenness thereof, it is preferable that as many organic layers as possible contained in the light-receiving layer 30 are formed using the organic material 60 for film formation.

The light receiving layer 30 can be formed by a dry film forming method or a wet film forming method. The dry film formation method is preferable because it is easy to form a uniform film and it is difficult for impurities to be mixed therein, and also because it is easy to control film thickness and to laminate different materials.

Specific examples of the dry film forming method include a physical vapor phase growth method such as a vacuum vapor deposition method, a sputtering method, an ion plating method and an MBE (molecular beam epitaxy) method, or a CVD method such as a plasma polymerization. The vacuum deposition method is preferable, and in the case of forming the film by the vacuum deposition method, the manufacturing conditions such as the degree of vacuum and the deposition temperature can be set by a usual method. When the light-receiving layer 30 is formed by a vapor deposition method, the larger the decomposition temperature than the deposition-possible temperature, the more preferable the thermal decomposition at the time of vapor deposition can be suppressed.

When the light-receiving layer 30 is formed by the dry film forming method, the degree of vacuum at the time of formation is preferably 1 x 10 &lt; ^-3 &gt; Pa or less, 10 ^-4 Pa or less, and more preferably, 1 × 10 ^-4 Pa or less it is particularly preferred.

The thickness of the light receiving layer 30 is preferably 10 nm or more and 1000 nm or less, more preferably 50 nm or more and 800 nm or less, and particularly preferably 100 nm or more and 600 nm or less. When it is 10 nm or more, a suitable dark current suppressing effect is obtained, and when it is 1000 nm or less, a suitable photoelectric conversion efficiency is obtained.

<< Photoelectric Conversion Layer >>

The photoelectric conversion layer 32 receives light and generates electric charges corresponding to the amount of light, and includes an organic photoelectric conversion material.

The photoelectric conversion element 1 of the present embodiment has a structure in which a mixed layer (bulk hetero layer) in which a p-type organic semiconductor (p-type organic compound) and an n-type organic semiconductor are mixed is provided in the photoelectric conversion layer 32 . This mixed layer is preferably formed by co-deposition of an organic material 60 for forming a p-type organic semiconductor material and an organic material 60 for forming an n-type organic semiconductor material.

Here, the mixed layer refers to a layer in which a plurality of materials are mixed or dispersed. In the present embodiment, the mixed layer is a layer formed by co-depositing a p-type organic semiconductor and an n-type organic semiconductor.

The n-type organic semiconductor (compound) constituting the photoelectric conversion layer 32 is not particularly limited, but fullerene or a fullerene derivative is preferable. The fullerene or fullerene derivative is not particularly limited, and fullerene C ₆₀ , fullerene C ₇₀ , fullerene C ₇₆ , fullerene C ₇₈ , fullerene C ₈₀ , fullerene C ₈₂ , fullerene C ₈₄ , fullerene C ₉₀ , fullerene C ₉₆ , fullerene C ₂₄₀ , Fullerene C ₅₄₀ , mixed fullerene, and fullerene nanotubes. Representative skeletons of fullerene are shown below.

[Chemical Formula 4]

The fullerene derivative refers to a compound to which a substituent is added. The substituent of the fullerene derivative is preferably an alkyl group, an aryl group or a heterocyclic group. The alkyl group is more preferably an alkyl group having 1 to 12 carbon atoms, and the aryl group and the heterocyclic group are preferably a benzene ring, a naphthalene ring, an anthracene ring, a phenanthrene ring, a fluorene ring, a triphenylene ring, , Biphenyl, pyrrole, furan, thiophene, imidazole, oxazole, thiazole, pyridine, pyrazine, pyrimidine, pyridazin, indolizin, indole, benzofuran , Benzothiophene ring, isobenzofuran ring, benzimidazole ring, imidazopyridine ring, quinolinine ring, quinoline ring, phthalazine ring, naphthyridine ring, quinoxaline ring, quinoxazoline ring, isoquinoline ring, Naphthalene ring, phenanthrene ring, phenanthrene ring, acridine ring, phenanthroline ring, thianthrene ring, chromane ring, zanthene ring, phenoxathiine ring, phenothiazine ring or phenazine ring, more preferably, Anthracene ring, phenanthrene ring, pyridine ring, imidazole ring, Or a thiazole ring, particularly preferably a benzene ring, a naphthalene ring, or a pyridine ring. These may further have a substituent, and the substituent may be bonded as far as possible to form a ring. In addition, a plurality of substituents may be present, and they may be the same or different. The plurality of substituents may be bonded to each other to form a ring as far as possible.

The photoelectric conversion layer 32 includes fullerene or a fullerene derivative so that charge generated by photoelectric conversion can be rapidly transported to the lower electrode 20 or the upper electrode 40 via the fullerene molecule or the fullerene derivative molecule. When the fullerene molecule or the fullerene derivative molecule is connected and the path of electrons is formed, the electron transporting property is improved and high-speed responsiveness of the organic photoelectric conversion element can be realized. Therefore, it is preferable that the fullerene or the fullerene derivative is contained in the photoelectric conversion layer 32 in an amount of 40% or more. However, if the amount of the fullerene or fullerene derivative is too large, the p-type organic semiconductor decreases and the bonding interface becomes small, and the exciton dissociation efficiency decreases.

If the ratio of the fullerene or the fullerene derivative in the photoelectric conversion layer 32 is too large, the amount of the p-type organic semiconductor decreases and the amount of absorption of the incident light decreases. Since the photoelectric conversion efficiency is thereby reduced, the fullerene or fullerene derivative contained in the photoelectric conversion layer 32 preferably has a composition of 85% or less.

In order to remarkably demonstrate the effect of the present invention, the p-type organic semiconductor is preferably a compound represented by the following general formula. It is preferable that the constituent organic substance has at least one amine moiety of the following formula (A) or a carbonyl group moiety of the following formula (B).

[Chemical Formula 1]

(2)

(Wherein ^{(A), R 30 ~ R} 31 are, each independently, an alkyl group which may have a substituent, represents a heteroaryl group which may have an aryl group or a substituent which may have a substituent. R ³² is a substituent R ³⁰ to R ³² may be connected to each other to form a ring. In the formula (B), Y ₁ represents an arylene group having two or more carbon atoms Or a condensed ring containing at least any one of a 5-membered ring, a 6-membered ring, or a 5-membered ring and a 6-membered ring, which may have a substituent. The substituents may be bonded to each other to form a ring .)

Further, in order to remarkably demonstrate the effect of the present invention, the p-type organic semiconductor is preferably a compound represented by the following formula (C).

(3)

(Wherein (C) of, Z ₄ represents a condensed ring containing at least two a ring containing carbon atoms and 5-membered ring, 6-membered ring, or at least one of a 5-membered ring and a 6-membered ring. L _1, L ₂ , And L &lt; ₃ &gt; each independently represent an unsubstituted methoxy group or a substituted methoxy group, and D &lt; ₁ &gt;

Z ₄ is a ring containing at least two carbon atoms, and represents a condensed ring containing at least one of a 5-membered ring, a 6-membered ring, or a 5-membered ring and a 6-membered ring. The fused ring containing at least one of a 5-membered ring, a 6-membered ring, or a 5-membered ring and a 6-membered ring is preferably a merocyanine dye and is preferably used as an acidic nucleus. Specific examples thereof include the following .

(a) a 1,3-dicarbonyl nucleus such as 1,3-indeundanone nucleus, 1,3-cyclohexanedione, 5,5-dimethyl-1,3-cyclohexanedione , 1,3-dioxane-4,6-dione, and the like.

(b) pyrazolone nucleus such as 1-phenyl-2-pyrazolin-5-one, 3-methyl-1-phenyl-2-pyrazolin- ) -3-methyl-2-pyrazolin-5-one.

(c) isoxazolinone nucleus such as 3-phenyl-2-isooxazolin-5-one, 3-methyl-2-isooxazolin-5-one and the like.

(d) oxyindole nucleus: for example, 1-alkyl-2,3-dihydro-2-oxyindole and the like.

(e) 2,4,6-Tricetohexahydropyrimidine nucleus: for example, bivalent or 2-thiobarbituric acid and derivatives thereof. Examples of the derivative include 1-alkyl such as 1-methyl and 1-ethyl, 1,3-dialkyl such as 1,3-dimethyl, 1,3-diethyl and 1,3- 1,3-di (p-chlorophenyl), and 1,3-di (p-ethoxycarbonylphenyl), and the like; 1-alkyl-1-aryl, 1,3-di (2-pyridyl), and the like.

(f) 2-thio-2,4-thiazolidinedione nucleus: for example, rhodanine and derivatives thereof. Examples of the derivatives include 3-alkylaldanines such as 3-methylordanine, 3-ethylordanine and 3-allyloxanine, 3-arylordanines such as 3- ) Third order heterocyclic substituted rhodanines such as rhodanine, and the like.

(g) 2-thio-2,4-oxazolidinedione (2-thio-2,4- (3H, 5H) -oxazole ion) 2,4-oxazolidinedione, and the like.

(h) Thianapthion nucleus: for example, 3 (2H) -thianaphthone-1,1-dioxide.

(i) 2-thio-2,5-thiazolidinedione ion nucleus such as 3-ethyl-2-thio-2,5-thiazolidinedione.

(j) 2,4-thiazolidinedione nuclei such as 2,4-thiazolidinedione, 3-ethyl-2,4-thiazolidinedione, 3-phenyl- Azolydinedione, and the like.

(k) Thiazolin-4-one nuclei such as 4-thiazolinone, 2-ethyl-4-thiazolinone, and the like.

(l) 2,4-imidazolidinedione (hydantoin) nucleus: 2,4-imidazolidinedione, 3-ethyl-2,4-imidazolidinedione, and the like.

(m) 2-thio-2,4-imidazolidinedione (2-thiohydantoin) nucleus: 2-thio-2,4-imidazolidinedione, -Thio-2,4-imidazolidinedione, and the like.

(n) 2-Imidazoline-5-one nuclei such as 2-propylmercapto-2-imidazolin-5-one and the like.

(o) 3,5-pyrazolidinedione nuclei such as 1,2-diphenyl-3,5-pyrazolidinedione, 1,2-dimethyl-3,5-pyrazolidinedione and the like.

(p) benzothiophen-3-one nuclei such as benzothiophen-3-one, oxobenzothiophen-3-one, dioxobenzothiophen-3-one and the like.

(q) indanone nucleus such as 1-indanone, 3-phenyl-1-indanone, 3-methyl-1-indanone, Methyl-1-indanone, and the like.

(r) benzofuran-3- (2H) -one nucleus: for example, benzofuran-3- (2H) -one and the like.

(s) 2,2-dihydrophenalene-1,3-dione ion nucleus.

They may also have a substituent W, and another ring may be cyclized.

L ₁ , L ₂ , and L ₃ each independently represent an unsubstituted meta-popular, or a substituted meta-popular. (E.g., a 6-membered ring such as a benzene ring) may be bonded to each other. The substituent of the substitution methoxy group may be a substituent W.

The substituent W will be described later.

n represents an integer of 0 or more, preferably an integer of 0 to 3, more preferably 0 to 2.

D ₁ represents an atomic group. For example, it is preferable to use a triarylamine compound, a benzidine compound, a pyrazoline compound, a styrylamine compound, a hydrazone compound, a triphenylmethane compound, or a carbazole compound.

Further, in order to remarkably demonstrate the effect of the present invention, the p-type organic semiconductor is preferably a compound represented by the following general formula (1).

[Chemical Formula 5]

(Wherein L ₂ and L ₃ each independently represent an unsubstituted methoxy group or a substituted methoxy group), n represents an integer of 0 to 2. Ar ₁ represents an arylene group which may have a bivalent substituent or an arylene group which may have a substituent Ar ₂ and Ar ₃ each independently represent a substituted aryl group, an unsubstituted aryl group, a substituted alkyl group, an unsubstituted alkyl group, a substituted heteroaryl group, or an unsubstituted heteroaryl group. L ₁ is an unsubstituted or substituted methoxy group bonded to the following general formula (2), or a group represented by the following general formula (3): wherein Ar ₁ , Ar ₂ , and Ar ₃ may be bonded to each other to form a ring. Lt; / RTI &gt;

[Chemical Formula 6]

Wherein Z ₁ is a ring containing a carbon atom bonded to L ₁ and a carbonyl group adjacent to the carbon atom, and includes a 5-membered ring, a 6-membered ring, a condensed ring containing at least one of a 5-membered ring and a 6-membered ring . X represents a hetero atom. Z ₂ represents a condensed ring containing at least any one of a 5-membered ring, a 6-membered ring, a 7-membered ring, a 5-membered ring, a 6-membered ring and a 7-membered ring, L ₄ to L ₆ each independently represent unsubstituted or substituted methoxy. R ₆ and R ₇ each independently represent a hydrogen atom or a substituent, and adjacent groups may be bonded to each other to form a ring. k represents an integer of 0 to 2; * In the general formula (2) represents a bonding position to be bonded to L ₁ , and * in the general formula (3) represents a bonding position to be bonded to L ₂ or Ar ₁ .

Z ₁ in the general formula (2) represents a condensed ring containing at least any one of a 5-membered ring, a 6-membered ring, or a 5-membered ring and a 6-membered ring containing at least two carbon atoms. As such a ring, it is usually preferable to use a melocyanine dye and it is used as an acidic nucleus. Specific examples thereof include, for example, the following.

The ring represented by Z ₁ is preferably a 1,3-dicarbonyl nucleus, a pyrazolone nucleus, a 2,4,6-triketohexahydropyrimidine nucleus (including a thioketone, for example, Thiobarbituric acid nucleus), 2-thio-2,4-thiazolidinedione nucleus, 2-thio-2,4-oxazolidinedione nucleus, 2-thio-2 Thiazolidinedione ion nucleus, a 2,4-thiazolidinedione ion nucleus, a 2-thio-2,4-imidazolidinedione ion nucleus, a 2- Pyrazolidinedione nucleus, benzothiophene-3-one nucleus, and indanone nucleus, and more preferably a 1,3-dicarbonyl nucleus, a 2,4- 6-triketohexahydropyrimidine nucleus (including thioketone, for example, bovisulphonic nucleus, 2-thiobarbital nucleus), 3,5-pyrazolidinedione nucleus, benzothiophene-3 -Onucleus, indanone nucleus, more preferably a 1,3-dicarbonyl nucleus, 2,4,6-tri Ketohexahydropyrimidine nucleus (including thioketone, for example, bovisulfuric acid nucleus and 2-thiobarbituric acid nucleus), particularly preferably 1,3-indeindan ion nucleus, bovisulphonic nucleus , 2-thiobarbituric acid nuclei and derivatives thereof.

Preferred as the ring represented by Z ₁ is represented by the following formula.

(7)

Z ³ is a ring containing a carbon atom bonded to L ₁ and two carbonyl groups adjacent to the carbon atom, and includes at least any one of a 5-membered ring, a 6-membered ring, or a 5-membered ring and a 6-membered ring Condensed ring. * Represents a bonding position to be bonded to L &lt; ₁ &gt;. Z ³ can be selected from the rings represented by Z ₁ , preferably 1,3-dicarbonyl nucleus, 2,4,6-tricetohexahydropyrimidine nucleus (including thioketone) Particularly preferred are 1,3-indene indanone nuclei, bovisulfuric acid nuclei, 2-thiobarbital nucleus and derivatives thereof.

When the ring represented by Z ₁ is a 1,3-indeindan ion nucleus, the group represented by the following general formula (5) is preferable.

[Chemical Formula 8]

In the formulas, R ₂ to R ₅ each independently represent a hydrogen atom or a substituent, and adjacent groups may bond to each other to form a ring. * Represents a bonding position to be bonded to L &lt; ₁ &gt;.

K in the general formula (3) represents an integer of 0 to 2, preferably 0 or 1, and more preferably 0. X is preferably O, S or NR &lt; _{10 &} gt ;. Preferred as the ring represented by Z ₂ is represented by the following formula (6).

[Chemical Formula 9]

Wherein X represents O, S, NR &lt; _{10 &} gt ;. R ₁₀ represents a hydrogen atom or a substituent. In the formula, R ₁ , R ₆ , and R ₇ each independently represent a hydrogen atom or a substituent, and adjacent groups may bond to each other to form a ring. m represents an integer of 1 to 3; When m is 2 or more, plural R _{1 s} may be the same or different. * Represents a bonding position to be bonded to L &lt; ₂ &gt; or Ar &lt; _{1 &} gt ;.

The arylene group represented by Ar ₁ is preferably an arylene group having 6 to 30 carbon atoms, and more preferably an arylene group having 6 to 18 carbon atoms. The arylene group may have a substituent, and is preferably an arylene group having 6 to 18 carbon atoms, which may have an alkyl group having 1 to 4 carbon atoms. For example, a phenylene group, a naphthylene group, a methylphenylene group, a dimethylphenylene group and the like are exemplified, and a phenylene group and a naphthylene group are preferable.

The aryl groups represented by Ar ₂ and Ar ₃ are each independently preferably an aryl group having 6 to 30 carbon atoms, and more preferably an aryl group having 6 to 18 carbon atoms. The aryl group may have a substituent, and is preferably an aryl group having 6 to 18 carbon atoms, which may have an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 18 carbon atoms. For example, a phenyl group, a naphthyl group, a tolyl group, an anthryl group, a dimethylphenyl group, a biphenyl group and the like are exemplified, and a phenyl group and a naphthyl group are preferable.

The alkyl group represented by Ar ₂ and Ar ₃ is preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 4 carbon atoms. For example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, and a t-butyl group are preferable and a methyl group or an ethyl group is preferable and a methyl group is more preferable.

The heteroarylene group represented by Ar ₁ and the heteroaryl group represented by Ar ₂ and Ar ₃ are each independently preferably a heteroaryl group having 3 to 30 carbon atoms and more preferably a heteroaryl group having 3 to 18 carbon atoms . The heteroaryl group may have a substituent, and is preferably a heteroaryl group having 3 to 18 carbon atoms, which may have an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 18 carbon atoms. The heteroarylene group represented by Ar ₁ , the heteroaryl group represented by Ar ₂ and Ar ₃ may be a condensed ring structure, or a furan ring, a thiophene ring, a selenopentane ring, a silole ring, a pyridine ring, a pyrazine ring, a pyrimidine ring, (Identical to) a ring selected from a pyridine ring, a thiazole ring, a thiazole ring, a thiazole ring, a triazole ring, an oxadiazole ring, and a thiadiazole ring is preferable, and a quinoline ring, an isoquinoline ring, a benzothiophene ring, A thienothiophene ring, a bithienobenzene ring, and a bithienothiophene ring are preferable.

Ar ₁ , Ar ₂ , Ar ₃ , R ₁ , R ₂ to R ₇ and R _{10 may} be adjacent to each other to form a ring. The ring is preferably a ring formed by a hetero atom, an alkylene group, an aromatic ring, or the like. For example, two of the aryl groups (for example, Ar ₁ , Ar ₂ and Ar _{3 in the} general formula (1)) are connected to each other through a single bond or a linking group to form a nitrogen atom (N in the formula (1) And a ring formed together. Examples of the linking group include a group consisting of a hetero atom (e.g., -O-, -S-, etc.), an alkylene group (e.g., a methylene group, an ethylene group and the like), and a combination thereof. , And a methylene group is preferable. (E.g., N in the formula (1)), an alkylene group (e.g., a methylene group), and an aryl group (for example, Ar ₁ , Ar ₂ or Ar _{3 in the} formula (1) A ring formed is preferable. (Preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group), and a plurality of such substituents may be bonded to each other to form a ring A benzene ring or the like) may be formed.

It is also preferable that R ₃ and R ₄ are connected to each other to form a ring, and the ring is preferably a benzene ring.

As to R ₁ , when there are a plurality of R _{1 s} (m is 2 or more), adjacent ones of the plurality of R _{1 s} may be connected to each other to form a ring, and the ring is preferably a benzene ring.

The substituent W or the substituent when Ar ₁ , Ar ₂ and Ar ₃ have a substituent and the substituent of R ₁ , R ₂ to R ₇ and R ₁₀ include a halogen atom, an alkyl group (cycloalkyl group, bicycloalkyl group, tri (Including a cycloalkyl group), a substituted alkyl group, an alkenyl group (including a cycloalkenyl group and a bicycloalkenyl group), an alkynyl group, an aryl group, a substituted aryl group, a heterocyclic group An alkoxy group, an aryloxy group, a silyloxy group, a heterocyclic oxy group, an acyloxy group, a carbamoyloxy group, an alkoxycarbonyl group, an aryloxycarbonyl group, an amino group (an anilino group An aminocarbonylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamino group, a sulfamoylamino group, an alkylsulfonylamino group, an alkylsulfonylamino group, a mercapto group, an alkylthio group, an arylthio group, a heterocyclic group An alkyl group and an arylsulfonyl group, an acyl group, a carbamoyl group, an aryl and a heterocyclic azo group, an imide group, a phosphino group, a phosphine group, a phosphine diazo group, (-OH (O) ₂ ), phosphato group (-OPO (OH) ₂ ), sulfato group (-OSO), phosphino group, phosphino group, silyl group, hydrazino group, ₃ H), and other known substituents. The substituent of R ₁ , R ₂ to R ₇ and R ₁₀ is preferably an alkyl group, a substituted alkyl group, an aryl group, a substituted aryl group, a heteroaryl group, a cyano group, a nitro group, an alkoxy group, A thio group, an alkenyl group, or a halogen atom is preferable.

When the substituent W or Ar ₁ , Ar ₂ or Ar ₃ has a substituent, the substituent may be independently selected from the group consisting of a halogen atom, an alkyl group, an aryl group, a heterocyclic group, a hydroxyl group, a nitro group, an alkoxy group, An oxy group, an amino group, an alkylthio group, an arylthio group, an alkenyl group, a cyano group or a heterocyclic thio group.

R ₁ is more preferably an alkyl group or an aryl group. As R ₆ and R ₇ , a cyano group is more preferable.

Examples of the substituent of the substituted alkyl group and the substituted aryl group include the above-exemplified substituents, an alkyl group (preferably an alkyl group having 1 to 4 carbon atoms, more preferably a methyl group), an aryl group (an aryl group having 6 to 18 carbon atoms , More preferably a phenyl group).

In the case where L ₁ , L ₂ , L ₃ , L ₄ , L ₅ and L ₆ each independently represent an unsubstituted methoxy group or a substituted methoxy group, the substituent group of the substitution methoxy group may be an alkyl group, An alkoxy group or an aryloxy group, and the substituents may be bonded to each other to form a ring. The ring may be a 6-membered ring (for example, a benzene ring). The substituents of L ₁ or L ₃ and Ar ₁ may be bonded to each other to form a ring. The substituents of L &lt; ₆ &gt; and R &lt; ₇ &gt; may be bonded to each other to form a ring.

The alkyl group represented by R ₁ , R ₂ to R ₇ and R ₁₀ is preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 4 carbon atoms. For example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group and t-butyl group. As R ₂ to R ₇ , a methyl group or an ethyl group is preferable, and a methyl group is more preferable. As R ₁ , a methyl group, an ethyl group or a t-butyl group is preferable, and a methyl group or a t-butyl group is more preferable. n is preferably 0 or 1.

The aryl groups represented by R ₁ , R ₂ to R ₇ and R ₁₀ are each independently preferably an aryl group having 6 to 30 carbon atoms, more preferably an aryl group having 6 to 18 carbon atoms. The aryl group may have a substituent, and is preferably an aryl group having 6 to 18 carbon atoms, which may have an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 18 carbon atoms. For example, a phenyl group, a naphthyl group, an anthracene group, a pyrenyl group, a phenanthrene group, a methylphenyl group, a dimethylphenyl group, and a biphenyl group are exemplified, and a phenyl group, a naphthyl group or an anthracene group is preferable.

Each of the heteroaryl groups represented by R ₁ , R ₂ to R ₇ and R ₁₀ is preferably a heteroaryl group having 3 to 30 carbon atoms, and more preferably a heteroaryl group having 3 to 18 carbon atoms. The heteroaryl group may have a substituent, and is preferably a heteroaryl group having 3 to 18 carbon atoms, which may have an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 18 carbon atoms. The heteroaryl group represented by R ₁ and R ₂ to R ₇ is preferably a heteroaryl group comprising 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 furan ring, thiophene ring, pyrrole ring, pyrrole ring, pyrrolidine ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, imidazole ring, imidazoline A thiazole ring, a pyrazole ring, a triazole ring, a furan ring, a tetrazole ring, a pyran ring, a thiazine ring, a pyridine ring, a piperidine ring, a oxazine ring, a morpholine ring, Pyrimidine ring, pyrimidine ring, pyrazine ring, piperazin ring, triazin ring and the like.

Examples of the condensed rings include benzofuran ring, isobenzofuran ring, benzothiophene ring, indole ring, indoline ring, isoindole ring, benzoxazole ring, benzothiazole ring, indazole ring, benzoimidazole ring, quinoline ring, isoquinoline A phenanthrene ring, a phenanthrene ring, a phenoxazine ring, a thianthrene ring, a phenanthrene ring, a phenanthrene ring, a phenanthrene ring, a phenanthrene ring, a thianthrene ring, A thiophene ring, a thienothiophene ring, an indolizine ring, a quinolinine ring, a quinuclidine ring, a naphthyridine ring, a purine ring, and a pteridine ring.

m represents an integer of 1 to 3, preferably 1 or 2, more preferably 1.

Of the organic p-type semiconductor materials containing the moiety represented by the general formula (A) or (B), the following compounds are preferable. Of these compounds, compounds 1, 2, 4, 5 and 6 are particularly preferred.

[Chemical formula 10]

(11)

[Chemical Formula 12]

[Chemical Formula 13]

<< Electronic blocking layer >>

The electron blocking layer 31 included in the light receiving layer 30 suppresses the injection of electrons from the lower electrode 20 into the photoelectric conversion layer 32 and electrons generated in the photoelectric conversion layer 32 pass through the electrode 20 ) Side of the layer. The electron blocking layer 31 is composed of an organic material or an inorganic material or both.

The electron blocking layer 31 may be composed of a plurality of layers. By doing so, an interface is formed between the respective layers constituting the electron blocking layer 31, and discontinuity occurs in the intermediate levels existing in each layer. As a result, the electron blocking effect can be enhanced because the movement of the charge through the intermediate level or the like becomes difficult. However, if the layers constituting the electron blocking layer 31 are made of the same material, the intermediate levels present in each layer may be completely the same. Therefore, in order to further enhance the electronic blocking effect, It is preferable that the materials are different from each other.

As the electron blocking layer 31, an electron donating organic material can be used. Specific examples of the low molecular material include N, N'-bis (3-methylphenyl) - (1,1'-biphenyl) -4,4'-diamine (TPD) or 4,4'-bis [N - (naphthyl) -N-phenyl-amino] biphenyl (? -NPD), oxazole, oxadiazole, triazole, imidazole, imidazolone, stilbene derivatives, pyrazoline derivatives , 4,4 ', 4 "-tris (N- (3-methylphenyl) N-phenylamino) triphenylamine (m-MTDATA), polyphosphine, tetraphenyl There can be mentioned a porphyrin compound such as phophinic copper, phthalocyanine, copper phthalocyanine, and titanium phthalocyanine oxide, a triazole derivative, an oxadiazole derivative, an imidazole derivative, a polyarylalkane derivative, a pyrazolone derivative, Diamine derivatives, arylamine derivatives, fluorene derivatives, amino substituted chalcone derivatives, oxazole derivatives, styryl anthracene derivatives, fluorine Pyrazine, pyrrole, picoline, thiophene, acetylene, diacetylene, and the like can be used as the polymer material, and examples of the polymer material include, for example, phenylene vinylene, fluorene, carbazole, indole, Or a derivative thereof can be used as the electron-transporting compound. It is possible to use a compound having sufficient hole transportability even if it is not an electron-donating compound.

Specifically, for example, the following compounds described in Japanese Patent Application Laid-Open No. 2008-72090 are shown, but the present invention is not limited thereto. In the following, Ea represents the electron affinity of the material and Ip represents the ionization potential of the material. EB-1, 2, ... Quot; EB "is an abbreviation of" electronic blocking ".

[Chemical Formula 14]

As the electron blocking layer 31, an inorganic material may be used. In general, since the inorganic material has a larger dielectric constant than the organic material, when the electron blocking layer 31 is used, a large amount of voltage is applied to the photoelectric conversion layer 32, so that the photoelectric conversion efficiency can be increased. Examples of the material that can be used as the electron blocking layer 31 include calcium oxide, chromium oxide, chromium oxide, manganese oxide, cobalt oxide, nickel oxide, copper oxide, gallium oxide copper, strontium oxide, Ribbedonium, indium copper oxide, indium oxide, and iridium oxide.

In the electron blocking layer 31 made of a plurality of layers, it is preferable that the layer adjacent to the photoelectric conversion layer 32 in the plurality of layers is a layer made of the same material as the p-type organic semiconductor included in the photoelectric conversion layer 32 . By using the same p-type organic semiconductor in the electron blocking layer 31 as well, it is possible to suppress formation of the intermediate level at the interface between the photoelectric conversion layer 32 and the adjacent layer, thereby further suppressing the dark current.

When the electron blocking layer 31 is a single layer, it may be a layer made of an inorganic material, or, in the case of a plurality of layers, one or two or more layers may be a layer made of an inorganic material.

When a bias voltage is applied so as to trap electrons in the lower electrode 20 and trap the holes in the upper electrode 40, a hole blocking layer may be provided in place of the electron blocking layer 31 . The hole blocking layer is formed of an organic material for inhibiting injection of holes from the lower electrode 20 into the photoelectric conversion layer 32 and preventing holes generated in the photoelectric conversion layer 32 from flowing to the lower electrode 20 side As shown in Fig. By forming a plurality of the hole blocking layers, the hole blocking effect can be enhanced.

Further, the electrons or holes collected in the upper electrode 40 may be converted into voltage signals corresponding to the amounts and taken out to the outside. In this case, an electron blocking layer or a hole blocking layer may be provided between the upper electrode 40 and the photoelectric conversion layer 32. In any case, the portion sandwiched between the lower electrode 20 and the upper electrode 40 becomes the light-receiving layer 30.

As the hole blocking layer, an electron-accepting organic material can be used. Examples of the electron-accepting material include oxadiazole derivatives such as 1,3-bis (4-tert-butylphenyl-1,3,4-oxadiazolyl) phenylene (OXD-7), anthraquinodimethane derivatives, (4-methyl-8-quinolinate) aluminum complexes, bis (4-methyl-8-quinolinate) aluminum complexes, benzophenone derivatives, , A diesterial arylene derivative, a silole compound, and the like. Further, even if it is not an electron-accepting organic material, it can be used if it is a material having sufficient electron transporting ability. A styryl compound or a 4H pyran compound such as a porphyrin compound or DCM (4-dicyanomethylene-2-methyl-6- (4- (dimethylaminostyryl)) -4H pyran) may be used.

The p-type organic semiconductor (compound) constituting the photoelectric conversion layer 32 is a donor organic semiconductor (compound), usually represented by a hole-transporting organic compound, and is an organic compound having a property of donating electrons. More specifically, it refers to an organic compound having a small ionization potential when two organic materials are used in contact with each other. Therefore, any organic compound can be used as long as the donor organic compound is an organic compound having an electron donor.

It is also preferable that the positive hole blocking layer is formed using the organic material 60 for film formation.

<Sealing Layer>

The sealing layer 50 is a layer for preventing a factor that deteriorates an organic material such as water or oxygen from entering the light-receiving layer containing an organic material. The sealing layer 50 is formed so as to cover the lower electrode 20, the electron blocking layer 31, the photoelectric conversion layer 32, and the upper electrode 40.

In the photoelectric conversion element 1, since the incident light reaches the photoelectric conversion layer 32 through the sealing layer 50, the photoelectric conversion layer 32 has sensitivity so that light is incident on the photoelectric conversion layer 32 It is necessary to be sufficiently transparent to the light of wavelength. Examples of the sealing layer 50 include ceramics such as dense metal oxides, metal nitrides, metal nitrides, and diamond-like carbon (DLC) that do not permeate water molecules. Conventionally, aluminum oxide, silicon oxide, Silicon oxynitride, a laminated film thereof, a laminated film of these and an organic polymer, and the like are used.

The sealing layer 50 may be formed of a thin film made of a single material. However, by providing a multilayer structure and providing a separate function to each layer, it is possible to reduce the stress of the entire sealing layer 50, Suppressing the occurrence of defects such as pinholes, and optimizing material development can be expected. For example, the sealing layer 50 may be formed by laminating a "sealing auxiliary layer" which has a function that is difficult to attain in a layer that achieves its original purpose of preventing permeation of deterioration factors such as water molecules A two-layer structure can be formed. It is possible to have three or more layers, but considering the manufacturing cost, it is preferable that the number of layers is as small as possible.

The method of forming the sealing layer 50 is not particularly limited and it is preferable that the sealing layer 50 is formed by a method that does not deteriorate the performance and the film quality of the photoelectric conversion layer 32 already formed. Conventionally, the conventional sealing layer is formed by various vacuum film forming techniques. However, since the conventional sealing layer is difficult to grow the thin film in the steps due to the structure of the substrate surface, micro-defects on the substrate surface, particles adhered to the substrate surface, and the like The film thickness becomes remarkably thinner than the flat part because the step becomes a shadow). As a result, the step portion becomes a path through which the degradation factor penetrates. In order to completely cover the stepped portion with the sealing layer, it is necessary to form the film so as to have a film thickness of at least 1 mu m in the flat portion, and to thicken the entire sealing layer. The degree of vacuum at the time of forming the sealing layer is preferably 1 x 10 ³ Pa or less, more preferably 5 x 10 ² Pa or less.

However, in the case of an imaging device having a pixel size of less than 2 占 퐉, particularly about 1 占 퐉, if the thickness of the sealing layer 50 is large, the distance between the color filter and the photoelectric conversion layer becomes distant and the incident light diffracts / diverges in the sealing layer , There is a possibility that color mixing occurs. Therefore, when considering application to an image pickup device having a pixel size of about 1 mu m, it is necessary to provide a sealing layer material / manufacturing method in which device performance is not degraded even if the film thickness of the sealing layer 50 is reduced.

The atomic layer deposition (ALD) method is a kind of CVD method in which an adsorption / reaction of an organometallic compound molecule, a metal halide molecule, and a metal hydride molecule to be a thin film material on a substrate surface and an unreacted Is repeated alternately to form a thin film. When the thin film material reaches the surface of the substrate, the thin film can be grown only in a very small space into which the low molecular material can enter because it is in the low molecular state. As a result, the step portion which is difficult to be formed by the conventional thin film forming method is completely covered (the thickness of the thin film grown on the step portion is equal to the thickness of the thin film grown on the flat portion). As a result, the steps due to the structure of the substrate surface, the micro-defects of the substrate surface, the particles adhered to the substrate surface, and the like can be completely covered, and such stepped portions do not become the flooding path of the deterioration factor of the photoelectric conversion material. When the formation of the sealing layer 50 is performed by the atomic layer deposition method, it becomes possible to thin the sealing layer film thickness more effectively than in the prior art.

When the sealing layer 50 is formed by the atomic layer deposition method, the material corresponding to the ceramics suitable for the sealing layer 50 can be appropriately selected. However, since the photoelectric conversion layer of the present invention uses an organic photoelectric conversion material, the organic photoelectric conversion material is limited to a material capable of thin film growth at a relatively low temperature without deterioration. According to the atomic layer deposition method using an alkyl aluminum or a halogenated aluminum material, a dense aluminum oxide thin film can be formed at a temperature lower than 200 캜 at which the organic photoelectric conversion material is not deteriorated. In particular, when trimethyl aluminum is used, an aluminum oxide thin film can be formed even at about 100 ° C, which is preferable. Silicon oxide or titanium oxide is also preferable because a dense thin film can be formed at a temperature of less than 200 占 폚 just like aluminum oxide by appropriately selecting a material.

In addition, the thin film formed by the atomic layer deposition method can attain a thin film of excellent quality at a low temperature in view of step coverage and compactness. However, the physical properties of the thin film material may deteriorate in the chemicals used in the photolithography process. For example, since the aluminum oxide thin film formed by the atomic layer deposition method is amorphous, the surface is eroded in an alkaline solution such as a developer or a peeling liquid.

In addition, a thin film formed by a CVD method such as an atomic layer deposition method has many tensile stresses having a very large internal stress. Thus, it is preferable to use a process in which intermittent heating and cooling are repeated like a semiconductor manufacturing process, By the preservation / use, the thin film itself may be slightly deteriorated.

Therefore, when the sealing layer 50 formed by the atomic layer deposition method is used, it is preferable to form the sealing auxiliary layer which is excellent in chemical resistance and capable of canceling the internal stress of the sealing layer 50.

Examples of the auxiliary sealing layer include a layer containing any one of metal oxides, metal nitrides, and ceramics such as metal nitride oxides formed by a physical vapor deposition (PVD) method such as a sputtering method and having excellent chemical resistance . The ceramics formed by the PVD method such as the sputtering method often have a large compressive stress and can cancel the tensile stress of the sealing layer 50 formed by the atomic layer deposition method.

The sealing layer 50 formed by the atomic layer deposition method preferably includes any one of aluminum oxide, silicon oxide, and titanium oxide, and the sealing auxiliary layer may be any of aluminum oxide, silicon oxide, silicon nitride, A sputter film containing any one is preferred. In this case, the film thickness of the sealing layer 50 is preferably 0.05 탆 or more and 0.5 탆 or less.

As described above, the photoelectric conversion element 1 is constituted.

The term "

Next, the configuration of an image pickup device (optical sensor) 100 provided with the photoelectric conversion element 1 will be described with reference to Fig. 3 is a schematic cross-sectional view showing a schematic structure of an image pickup device for explaining an embodiment of the present invention. The image pickup device is used by being mounted on an image pickup device such as a digital camera or a digital video camera, an image pickup module such as an electronic endoscope, or a mobile phone.

The image pickup device 100 includes a plurality of organic photoelectric conversion elements 1 each having a configuration as shown in Fig. 1 and a circuit having a readout circuit for reading signals corresponding to charges generated in the photoelectric conversion layers of the organic photoelectric conversion elements And a plurality of organic photoelectric conversion elements are arranged in a one-dimensional or two-dimensional shape on the same plane above the circuit board.

The imaging element 100 includes a substrate 101, an insulating layer 102, a connecting electrode 103, a pixel electrode 104, a connecting portion 105, a connecting portion 106, a light receiving layer 107 A buffer layer 109, a sealing layer 110, a color filter (CF) 111, a barrier rib 112, a light shielding layer 113 and a protective layer 114 A counter electrode voltage supply unit 115, and a read circuit 116. [

The pixel electrode 104 has the same function as the lower electrode 20 of the organic photoelectric conversion element 1 shown in Fig. The counter electrode 108 has the same function as the top electrode 40 of the organic photoelectric conversion element 1 shown in Fig. The light receiving layer 107 has the same structure as the light receiving layer 30 provided between the lower electrode 20 and the upper electrode 40 of the organic photoelectric conversion element 1 shown in Fig. The sealing layer 110 has the same function as the sealing layer 50 of the organic photoelectric conversion element 1 shown in Fig. A part of the opposing electrode 108 facing the pixel electrode 104, a light receiving layer 107 sandwiched between these electrodes, a buffer layer 109 opposed to the pixel electrode 104, and a part of the sealing layer 110 Constitute an organic photoelectric conversion element.

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

The light-receiving layer 107 is a layer common to all of the organic photoelectric conversion elements provided over the plurality of pixel electrodes 104.

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

The connection portion 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 portion 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 pickup device, the power supply voltage is boosted by a boost circuit such as a charge pump to supply the predetermined voltage.

The read circuit 116 is provided on the substrate 101 in correspondence with each of the plurality of pixel electrodes 104 and reads signals corresponding to the charges collected by the corresponding pixel electrodes 104. [ The reading circuit 116 is composed of, for example, a CCD, a MOS circuit, or a TFT circuit, and is shielded by a shielding layer (not shown) disposed in the insulating layer 102. The reading circuit 116 is electrically connected to the corresponding pixel electrode 104 through the connection portion 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 barrier ribs 112 are provided between the color filters 111 to improve the light transmission efficiency of the color filters 111.

The light shielding layer 113 is formed outside the region where the color filter 111 and the barrier rib 112 are provided on the sealing layer 110 to prevent light from entering the light receiving layer 107 formed outside the effective pixel region. The protective layer 114 is formed on the color filter 111, the partition wall 112, and the light shielding layer 113 to protect the entire image pickup device 100.

In the image pickup device 100 constructed as described above, when light is incident, this light enters the light-receiving layer 107, and charges are generated there. The holes in the generated charge are collected by the pixel electrode 104 and a voltage signal corresponding to the amount is output to the outside of the image pickup device 100 by the read circuit 116.

A method of manufacturing the image pickup device 100 is as follows.

The connection portions 105 and 106, the plurality of connection electrodes 103, the plurality of pixel electrodes 104 and the insulating layer 102 are formed on the circuit board on which the counter electrode voltage supplying portion 115 and the reading circuit 116 are formed . The plurality of pixel electrodes 104 are arranged on the surface of the insulating layer 102, for example, in a tetragonal lattice pattern.

Next, a light receiving layer 107, a counter electrode 108, a buffer layer 109, and a sealing layer 110 are formed in this order on the plurality of pixel electrodes 104. The method of forming the light-receiving layer 107, the counter electrode 108 and the sealing layer 110 is as described in the description of the photoelectric conversion element 1. [ The buffer layer 109 is formed by, for example, resistance heating deposition. Next, after the color filter 111, the partition wall 112, and the light shielding layer 113 are formed, the protective layer 114 is formed to complete the imaging element 100. [

In the above description, the photoelectric conversion element suitable as the image pickup element and the image pickup element has been described in which the light-receiving layer is formed using the organic material for film formation of the present invention. However, the organic material for film formation 60 of the present invention , An organic electroluminescent element, and an electroluminescent element suitable as an organic electroluminescent element.

Example

&Lt; Preparation of organic materials for film formation >

(Compound 1)

First, an organic material for film formation of Compound 1 was prepared.

Compound 1 was synthesized in accordance with the steps shown in the following reaction formulas.

[Chemical Formula 15]

[Chemical Formula 16]

(Synthesis of Compound 1a)

N-phenyl-2-naphthylamine (manufactured by Tokyo Chemical Industry Co., Ltd.), methyl 6-bromo-2-naphthoate (manufactured by Wako Pure Chemical Industries, Ltd.), palladium acetate, triphenylphosphine and cesium carbonate were added to dehydrated xylene , And refluxed for 3 hours. The reaction mixture was subjected to suction filtration, the solvent was distilled off with an evaporator, and the residue was purified by silica gel column (developing solvent: toluene). The solvent was distilled off to obtain the compound (1a).

(Synthesis of compound 1b)

SMEAH (hydrogenated bis (2-methoxyethoxy) aluminum sodium · toluene solution (about 70%) (manufactured by Wako Pure Chemical Industries, Ltd.)) was added to dehydrated toluene and the internal temperature was adjusted to 0 캜 with an ice bath. A solution in which razine was dissolved in dehydrated toluene was added dropwise. The compound (1a) was dissolved in dehydrated toluene, and the internal temperature was adjusted to -40 캜 with a dry ice bath, and then the SMEAH toluene solution prepared above was added dropwise thereto. After stirring for 4.5 hours, conc. Hydrochloric acid was added until the pH reached 1. To this, water and ethyl acetate were added, and the oil layer was washed with an aqueous solution of sodium hydrogencarbonate. The oil layer was dried with magnesium sulfate, filtered, and the solvent was distilled off with an evaporator. The reaction mixture was purified by silica gel column and the solvent was distilled off to obtain compound (1b).

(Synthesis of Compound (1)) [

Compound (Ib) and benzoindeindane were added to a mixed solvent of toluene and ethanol, and refluxed for 2 hours. After cooling, the compound (1) was obtained by suction filtration.

(Purification process)

Next, Compound 1 (crude substance) obtained is purified. In this purification step, purification was repeated or a plurality of purification methods were combined to obtain Compound 1 having a different fluorescence quantum yield value. [Purification method example: The obtained compound was dispersed in a solvent (a small amount of chloroform) and washed. Or dissolved in a solvent (a small amount of chloroform) and recrystallized with ethanol. Or sublimation purification.

(Compounds 2 to 11)

As for the purification process, the organic materials for film formation made of the compounds 2 to 11 were prepared in the same manner as the compound 1.

Compound 2 was synthesized in accordance with the steps shown in the following reaction formula.

[Chemical Formula 17]

&Lt; Synthesis of Compound 2 >

[Chemical Formula 18]

2-isopropenyl aniline, palladium acetate, tri (t-butyl) phosphine, cesium carbonate, and methyl 6-bromo-2-naphthoate were dissolved in xylene and the reaction was carried out in a non- To give compound 2a. Compound 2a was added to a mixed solvent of acetic acid and hydrochloric acid and stirred at 60 占 폚 for 30 minutes to obtain compound 2b. Compound 2b, palladium acetate, tri (t-butyl) phosphine, cesium carbonate, and bromobenzene were dissolved in xylene and reacted under non-refluxing for 7 hours under nitrogen atmosphere to obtain compound 2c. 70% toluene solution of hydrogenated bis (2-methoxyethoxy) aluminum (SMEAH) was added to THF in a nitrogen atmosphere, and the mixture was cooled to 0 占 폚. N-methylpiperazine is added dropwise and stirred for 30 minutes to prepare a reducing agent solution. A reducing agent solution was added dropwise to the THF solution of the compound 2c at -40 占 폚 in a nitrogen atmosphere. The reaction solution was stirred at -20 占 폚 for 4 hours and quenched with dilute hydrochloric acid to obtain compound 2d. Compound 2d and benzoindene indanone were dissolved in a THF solvent in a nitrogen atmosphere, refluxed for 3 hours, filtered, and filtered to obtain Compound 2.

Compound 3 was synthesized in accordance with the steps shown in the following reaction formulas.

[Chemical Formula 19]

[Chemical Formula 20]

An organic material for film formation of Compound 4 was synthesized.

[Chemical Formula 21]

&Lt; Synthesis of Compound (4)

Except that N-phenyl-2-naphthylamine was replaced with 1,2'-dinaphthylamine (manufactured by Tokyo Chemical Industry Co., Ltd.) in the compound 1.

An organic material for film formation of Compound 5 was synthesized.

[Chemical Formula 22]

&Lt; Synthesis of Compound (5)

Synthesis was conducted in the same manner as in Compound 1 except that N-phenyl-2-naphthylamine was changed to 2,2'-dinaphthylamine (manufactured by Tokyo Kasei Kasei).

An organic material for film formation of Compound 6 was synthesized.

(23)

&Lt; Synthesis of Compound 6 >

Except that 1b was changed to 4- (N, N'-diphenylamino) benzaldehyde (manufactured by Tokyo Chemical Industry Co., Ltd.) in the compound 1.

An organic material for film formation of Compound 7 was synthesized.

&Lt; EMI ID =

<Synthesis of Compound 7>

Chem. Mater. (Dicyanomethylene) -2-t-butyl-6- (p-diphenylaminostyryl) -4H-pyran on page 13, pp. 456-458, 2001,

Compound 8 was synthesized in accordance with the steps shown in the following reaction formula.

(25)

(26)

The compound 1 was synthesized in the same way except that 1b was changed to 3b and benzoindeindane was replaced with indeindaine. Compound 3b was synthesized as follows. Compound 3a was dissolved in dehydrated N, N-dimethylformamide, and trifluoromethanesulfonic anhydride was added dropwise thereto. The mixture was heated to 90 DEG C under a nitrogen atmosphere and stirred for 1 hour to obtain a compound 3b. Compound 3a was prepared as described in Org. Lett. 2009, 11, 1-4.

An organic material for film formation of Compound 9 was synthesized.

(27)

&Lt; Synthesis of Compound 9 >

Was synthesized in the same manner as Compound 1 except that N-phenyl-2-naphthylamine was changed to N- (2,4,6-trimethylphenyl) -4-biphenylamine.

An organic material for film formation of Compound 10 was synthesized.

(28)

The compound 2 was synthesized in the same way except that benzoindene indane was changed to 4,7-difluoro-1,3-indeindan ion.

An organic material for film formation of Compound 11 was synthesized.

[Chemical Formula 29]

The compound 8 was synthesized in the same manner except that the indene ion was changed to 5,6-dichloro-1,3-indeindan ion.

&Lt; Measurement of fluorescence quantum yield >

Compound 1 used in each of Examples 1 to 3 and Comparative Examples 1 to 2 is shown in Table 1 together with the fluorescence quantum yield. The fluorescence quantum yield of each example was measured using 10 mg of the powder of each example, manufactured by Hamamatsu Photonics; And measured with an absolute fluorescence quantum yield measuring apparatus (model number: C9920-02).

Similarly, the compounds 2 to 11 used in the examples of Examples 4 to 13 and Comparative Examples 3 to 16 are shown in Table 1 together with the fluorescence quantum yield.

The powders used in Examples 2 and 6 were pulverized by pulverization to obtain powder having an average particle size of less than 20 mu m. In Examples 14 to 15, the values of the fluorescence quantum yields are shown in Table 1. It has been confirmed that the value of the fluorescence quantum yield decreases with the refinement of the powder.

As Comparative Example 17, fullerene C _{60, which} is an n-type material, is shown in Table 1 together with the value of the fluorescence quantum yield.

&Lt; Fabrication of Photoelectric Conversion Element &

A glass substrate was prepared, and an amorphous ITO lower electrode (30 nm thick) was formed on the substrate by a sputtering method. Subsequently, the EB-3 was formed as an electron blocking layer by a resistance heating deposition method (100 nm thickness).

Next, Compound 1 (the fluorescent quantum yield is shown in Table 1) and fullerene (C ₆₀ ) were prepared as the organic materials for the photoelectric conversion layer for each of the examples, respectively. Then, on the electron blocking layer, 500 nm thick.

Vacuum deposition of the electron blocking layer and the photoelectric conversion layer was performed at a vacuum degree of 4 x 10 &lt; ~ ⁴ &gt; The HPLC purity of each material used was 99.5% or more, and the volume ratio of the fullerene to the compound 1 in the formed photoelectric conversion layer was 2: 1 (converted to film thickness).

Next, an amorphous ITO upper electrode (10 nm thick) was formed on the photoelectric conversion layer by a sputtering method to obtain a photoelectric conversion element of the present invention. On the upper electrode, a SiO film was formed by thermal evaporation as a sealing layer, and an Al ₂ O ₃ layer was formed by the ALCVD method to obtain a photoelectric conversion element.

[evaluation]

LED light having a center wavelength of 525 nm was incident on each photoelectric conversion element obtained from the upper electrode (transparent conductive film) side. The photoelectric conversion element was applied with an electric field of 2 x 10 &lt; ⁵ &gt; V / cm and the residual image current value after 0.1 second from the time when the incident LED light was turned off was evaluated. The evaluation results are shown in Table 1 below.

Likewise, the photoelectric conversion elements were produced using the compounds having different fluorescence quantum yields in the compounds 2 to 11, and the residual image current values of Examples 4 to 13 and Comparative Examples 3 to 16 were obtained. The solvent used for the purification was timely selected from chloroform, toluene and methylene chloride. The HPLC purity of each material used and the electron blocking layer EB-3 is 99.5% or more each.

In Table 1, the residual image current value is represented by a relative value with the reference value 10 being the value of Example 6.

Fig. 4 shows the relationship between the fluorescence quantum yield of the powder obtained based on the results of Table 1 and the residual image current value of the photoelectric conversion element. As shown in Fig. 4, it was confirmed that the residual image current value of the photoelectric conversion element was abruptly increased with the fluorescence quantum yield of 0.2 as a boundary. It was also confirmed that the residual image current value did not change even when the average particle diameter of the powder was less than 20 占 퐉.

[Table 1]

Industrial availability

INDUSTRIAL APPLICABILITY The organic film forming organic material and the film forming method using the organic film forming film of the present invention can be applied to organic imaging devices mounted on digital cameras, cellular phones, cameras for endoscopes, organic light emitting devices mounted on organic EL displays, It can be suitably applied to the formation of an organic layer of an organic photoelectric conversion element used for an organic thin film transistor or an optical sensor mounted on a wireless tag or the like.

Claims (18)

A light-receiving layer forming method for forming a light-receiving layer of an organic photoelectric conversion element used for an optical sensor by dry film formation,
Wherein at least one selected from recrystallization and dispersion in a solvent is added to the p-type semiconductor material having at least one amine group represented by the following formula (A) or a carbonyl group represented by the following formula (B) A step of performing a sublimation purification step or a step of performing dispersion in a solvent at least two times is carried out to prepare at least one organic material for film formation comprising a powder having a fluorescent quantum yield of 0.2 or more and 0.4 or less ,
Wherein the dry film formation is carried out using a gas source including the organic material for film formation.
[Chemical Formula 1]

(2)

(Wherein ^{(A), R 30 ~ R} 31 are, each independently, an alkyl group which may have a substituent, represents a heteroaryl group which may have an aryl group or a substituent which may have a substituent. R ³² is a substituent Or a heteroarylene linking group which may have a substituent, and R ³⁰ to R ³² may be connected to each other to form a ring.
In formula (B), Y ₁ represents a condensed ring containing at least any one of a 5-membered ring, a 6-membered ring, or a 5-membered ring and a 6-membered ring containing two or more carbon atoms, do.) The method according to claim 1,
Wherein the constituent organic substance is the following formula (C).
(3)

(Wherein, Z ₄ is at least two as the ring containing a carbon atom, a 5-membered ring, 6-membered ring, or a 5 shows a torus and 6 condensed ring containing at least one of a torus. L _1, L _2, and L ₃ each independently represent an unsubstituted methoxy group or a substituted methoxy group, D ₁ represents an atom group, and n represents an integer of 0 or more. The method according to claim 1,
Wherein the dry film formation is a resistance heating deposition method. The method according to claim 1,
Wherein the light-receiving layer is a photoelectric conversion layer. A manufacturing method of an organic photoelectric conversion element having a pair of electrodes and a light receiving layer including at least a photoelectric conversion layer sandwiched between the pair of electrodes,
Wherein the light-receiving layer is formed by the light-receiving layer forming method according to any one of claims 1 to 4. delete delete delete delete delete delete delete delete delete delete delete delete delete

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