KR101777534B1 - Photoelectric conversion element, imaging element and photosensor - Google Patents

Abstract

The present invention provides a photoelectric conversion element having a photoelectric conversion film exhibiting excellent response and manufacturability, and an imaging element and an optical sensor including the element. The photoelectric conversion element of the present invention is a photoelectric conversion element obtained by laminating a conductive film, a photoelectric conversion film containing a photoelectric conversion material, and a transparent conductive film in this order, wherein the photoelectric conversion material is a compound represented by the general formula (1) .

Description

PHOTOELECTRIC CONVERSION ELEMENT, IMAGING ELEMENT AND PHOTOSENSOR Field of the Invention [0001]

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

A conventional optical sensor is a device in which a photodiode PD is formed in a semiconductor substrate such as silicon (Si). As the solid-state image pickup device, PDs are arranged two-dimensionally, Flat-type solid-state image pickup devices are widely used.

In order to realize a color solid-state image pickup device, a structure in which a color filter transmitting light of a specific wavelength is disposed on the light incident surface side of the planar solid-state image pickup device is generally used. 2. Description of the Related Art [0002] In recent years, a single-plate type solid-state imaging device in which color filters transmitting blue (B) light, green (G) light and red (R) light are regularly arranged on each two- An imaging device is well known.

In this single plate type solid-state image pickup device, light which has not passed through the color filter is not used and the light utilization efficiency is poor. In recent years, with the progress of multi-pixel processing, the pixel size is getting smaller, which causes a problem of lowering the aperture ratio and lowering the light-condensing efficiency.

In order to solve such drawbacks, a structure is known in which a photoelectric conversion film made of amorphous silicon or a photoelectric conversion film using another photoelectric conversion material is formed on a signal reading substrate.

There are several known examples of the photoelectric conversion element using the photoelectric conversion film.

For example, Patent Document 1 discloses a photoelectric conversion element having a photoelectric conversion material layer of the following structural formula (1).

[Chemical Formula 1]

Patent Document 1: Japanese Laid-Open Patent Publication No. 2011-199152

In recent years, there has been a demand for improvement in characteristics such as the response speed required for a photoelectric conversion film used for an image pickup element, an optical sensor, and the like, in order to improve the performance thereof.

In addition, in response to a demand for lowering the cost of various devices in which the photoelectric conversion element is used, it has become important to produce the photoelectric conversion element more productively. Generally, the photoelectric conversion film in the photoelectric conversion element is manufactured by deposition or the like, and it is preferable that no performance difference occurs between the lots of the photoelectric conversion elements to be manufactured. That is, in a manufacturing line in which a photoelectric conversion film is formed by a deposition process, when the continuous deposition is performed by putting the photoelectric conversion material into the crucible of the deposition apparatus, the photoelectric conversion element manufactured at the initial stage of manufacture, In the conversion element, a photoelectric conversion element having no difference in response speed, that is, a photoelectric conversion element having excellent manufacturability is preferable.

The present inventors have made the photoelectric conversion element using the compound disclosed in Patent Document 1 and have found that the response speed of the obtained photoelectric conversion element and the manufacturing aptitude do not necessarily reach the levels required these days, I found that further improvement is needed.

In view of the above, it is an object of the present invention to provide a photoelectric conversion element having a photoelectric conversion film which exhibits excellent response and manufacturability.

It is also an object of the present invention to provide an image pickup device and an optical sensor including a photoelectric conversion element.

The inventors of the present invention have made intensive investigations on the above problems, and as a result, they found that the above problems can be solved by using a photoelectric conversion film containing a compound having a predetermined ring structure, and have completed the present invention.

That is, the above problems can be solved by means described below.

(1) A photoelectric conversion element having a conductive film, a photoelectric conversion film containing a photoelectric conversion material, and a transparent conductive film in this order, wherein the photoelectric conversion material comprises a compound represented by the following general formula (1) device.

(2) In the general formula (1), Ar ¹ and R ¹ , Ar ¹ and R ² , and at least one of R ¹ and R ² , and Ar ² and R ³ , Ar ² and R ^4, and R ³ and R ⁴ And at least one of them is bonded to each other to form a ring.

(3) The compound according to (1) or (2), wherein in the general formula (1), the group forming a ring in R ¹ , R ² , R ³ and R ⁴ is an aryl group which may have a substituent or a heteroaryl group which may have a substituent (2).

(4) The photoelectric conversion element according to any one of (1) to (3), wherein in the general formula (1), Ar ¹ and R ¹ , and Ar ² and R ³ are bonded to each other to form a ring.

(5) The photoelectric conversion element according to any one of (1) to (4), wherein A ¹ is a group represented by the general formula (2-1).

(6) The photoelectric conversion element according to any one of (1) to (5), wherein X ¹ and X ² in the general formula (1) are both oxygen atoms.

(7) The photoelectric conversion element according to any one of (1) to (6), wherein the dipole moment of the compound represented by the general formula (1) is 1D or less.

(8) The photoelectric conversion element according to any one of (1) to (7), wherein the molecular weight of the compound represented by the general formula (1) is 500 or more and less than 850.

(9) The photoelectric conversion element according to any one of (1) to (8), wherein the photoelectric conversion film further comprises an organic n-type compound.

(10) A photoelectric conversion element according to any one of (1) to (9), wherein a charge blocking film is disposed between the conductive film and the transparent conductive film.

(11) An optical sensor comprising a photoelectric conversion element according to any one of (1) to (10).

(12) An imaging device comprising a photoelectric conversion element according to any one of (1) to (10).

According to the present invention, it is possible to provide a photoelectric conversion element having a photoelectric conversion film exhibiting excellent response and manufacturability.

Further, according to the present invention, it is possible to provide an image pickup device and an optical sensor including a photoelectric conversion element.

1 (a) and 1 (b) are cross-sectional schematic diagrams each showing one configuration example of a photoelectric conversion element.
2 is a cross-sectional schematic diagram of one pixel of the hybrid type photoelectric conversion element.
3 is a schematic cross-sectional view of one pixel of the imaging device.

Hereinafter, preferred embodiments of the photoelectric conversion element of the present invention will be described.

One of the characteristic points compared with the prior art of the present invention is that a compound represented by the general formula (1) having a predetermined structure is used. This compound has a structure of a donor portion-acceptor portion-donor portion. That is, since the structure has a contrasting structure having the donor portion on both sides, the dipole moment of the compound itself is relatively low, and it is difficult to trap the carrier. In addition, since the donor portion contains a nitrogen atom capable of stabilizing a cation radical, the charge transportability is excellent. In addition, since the nitrogen atoms in the donor moiety are introduced into the ring structure, the structure is rigid and the heat resistance is improved, and even when continuous deposition is performed for a long time, decomposition of the compound and the like hardly occur and consequently, the production suitability of the photoelectric conversion element is excellent .

Hereinafter, preferred embodiments of the photoelectric conversion element of the present invention will be described with reference to the drawings. 1 is a schematic cross-sectional view of one embodiment of the photoelectric conversion element of the present invention.

The photoelectric conversion element 10a shown in Fig. 1A includes a conductive film (hereinafter also referred to as a lower electrode) 11 functioning as a lower electrode, an electron blocking film 16A formed on the lower electrode 11, , A photoelectric conversion film 12 formed on the electron blocking film 16A and containing a compound represented by the following general formula (1), and a transparent conductive film (hereinafter also referred to as an upper electrode) (15) are stacked in this order.

An example of the configuration of the photoelectric conversion element in Fig. 1 (b) is shown. The photoelectric conversion element 10b shown in Fig. 1 (b) includes an electron blocking film 16A, a photoelectric conversion film 12, a hole blocking film 16B, and an upper electrode 15) are stacked in this order. The stacking order of the electron blocking film 16A, the photoelectric conversion film 12, and the hole blocking film 16B in Figs. 1A and 1B may be reversed depending on applications and characteristics. For example, the positions of the electron blocking film 16A and the photoelectric conversion film 12 may be reversed.

In the structure of the photoelectric conversion element 10a (10b), it is preferable that light is incident on the photoelectric conversion film 12 through the transparent conductive film 15.

When the photoelectric conversion element 10a (10b) is used, an electric field can be applied. In this case, it is preferable that the conductive film 11 and the transparent conductive film 15 constitute a pair of electrodes, and an electric field of 1 × 10 ^-5 to 1 × 10 ⁷ V / cm is applied between the pair of electrodes Do. From the viewpoint of performance and power consumption, an electric field of 1 × 10 ^-4 to 1 × 10 ⁶ V / cm is preferable, and an electric field of 1 × 10 ^-3 to 5 × 10 ⁵ V / cm is particularly preferable.

1 (a) and 1 (b), it is preferable that the electron blocking film 16A side be a cathode and the photoelectric conversion film 12 side be an anode. When the photoelectric conversion element 10a (10b) is used as an optical sensor or when it is introduced into an image pickup device, the voltage can be applied by the same method.

2 is a schematic cross-sectional view of another embodiment of the photoelectric conversion element of the present invention.

The photoelectric conversion element 200 shown in Fig. 2 shows a hybrid photoelectric conversion element having an organic photoelectric conversion film 209 and an inorganic photoelectric conversion film 201. [ The organic photoelectric conversion film 209 includes a compound represented by the following general formula (1).

The inorganic photoelectric conversion film 201 has an n-type well 202, a p-type well 203 and an n-type well 204 on a p-type silicon substrate 205.

the blue light is photoelectrically converted (B pixel) by the pn junction formed between the p-type well 203 and the n-type well 204 and the pn junction formed between the p-type well 203 and the n- The red light is photoelectrically converted by the junction (R pixel). In addition, the conductivity type of each of the wells 202, 203, and 204 is not limited to these, and may be an opposite conductivity type.

On the inorganic photoelectric conversion film 201, a transparent insulating layer 207 is formed.

On the insulating layer 207, there is formed a transparent pixel electrode 208 divided for each pixel, and an organic photoelectric conversion film 209 for absorbing and photoelectrically converting green light is formed thereon in a single sheet configuration common to each pixel, On top of that, the electron blocking film 212 is formed in one sheet in common for each pixel, on which a transparent common electrode 210 having a single sheet of constitution is formed, and a transparent protective film 211 is formed on the uppermost layer have. The stacking order of the electron blocking film 212 and the organic photoelectric conversion film 209 may be opposite to that of FIG. 2, and the common electrode 210 may be formed separately for each pixel.

The organic photoelectric conversion film 209 constitutes a G pixel for detecting green light.

The pixel electrode 208 is the same as the lower electrode 11 of the photoelectric conversion element 10a shown in Fig. The common electrode 210 is the same as the upper electrode 15 of the photoelectric conversion element 10a shown in Fig.

Green light in the incident light is absorbed by the organic photoelectric conversion film 209 to generate photo charges and this photocharge is transferred from the pixel electrode 208 to the green And accumulates in the signal charge accumulation region.

Mixed light of the blue light and the red light transmitted through the organic photoelectric conversion film 209 enters the inorganic photoelectric conversion film 201. The blue light having a short wavelength is photoelectrically converted mainly at the heavily portion of the semiconductor substrate (inorganic photoelectric conversion film) 201 (near the pn junction formed between the p-type well 203 and the n-type well 204) A light charge is generated, and a blue signal is output to the outside. The red light having a long wavelength is photoelectrically converted mainly at the deep portion of the semiconductor substrate (inorganic photoelectric conversion film) 201 (near the pn junction formed between the p-type well 203 and the n-type well 202) And a red signal is output to the outside.

When the photoelectric conversion element 200 is used for an image pickup device, a signal reading circuit (a charge transfer path in the case of a CCD or a MOS transistor circuit in the case of a CMOS transistor) or a green signal charge accumulation Regions are formed. The pixel electrode 208 is connected to the corresponding green signal charge accumulation region by the vertical interconnection.

Hereinafter, aspects of each layer constituting the photoelectric conversion element of the present invention will be described in detail.

[Photoelectric Conversion Film]

The photoelectric conversion film 12 (or the organic photoelectric conversion film 209) is a film containing a compound represented by the following general formula (1) as a photoelectric conversion material. By using this compound, a photoelectric conversion element having a photoelectric conversion film exhibiting excellent responsiveness and manufacturability is obtained.

Hereinafter, the compound represented by the general formula (1) will be described in detail.

(2)

In the general formula (1), R ¹ to R ⁴ each independently represent an alkyl group, an aryl group which may have a substituent, a heteroaryl group which may have a substituent, or an alkenyl group which may have a substituent. Among them, an aryl group, which may have a substituent, or a substituent (s), which has a better response and / or manufacturability of the photoelectric conversion element (hereinafter simply referred to as " Is preferable, and an aryl group which may have a substituent is more preferable.

Among the groups represented by R ¹ , R ² , R ³ , and R ⁴ , the group included in the ring forming group described later is preferably an aryl group which may have a substituent or an aryl group which may have a substituent It is preferably a heteroaryl group. That is, for example, when a ring is formed by R ¹ and Ar ¹ , it is preferable that R ¹ is an aryl group which may have a substituent or a heteroaryl group which may have a substituent.

The number of carbon atoms in the alkyl group is not particularly limited, but is preferably from 1 to 10, more preferably from 1 to 6, and still more preferably from 1 to 3, from the viewpoint of more excellent effects of the present invention. The alkyl group may be any of straight-chain, branched, and cyclic structures.

Preferred examples of the alkyl group include a methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group and n-hexyl group.

The number of carbon atoms in the aryl group is not particularly limited, but is preferably from 6 to 30, and more preferably from 6 to 18, from the viewpoint of more excellent effects of the present invention. The aryl group may be a monocyclic structure, a condensed ring structure in which two or more rings are coordinated, and may have a substituent W described later.

Examples of the aryl group include a phenyl group, a naphthyl group, an anthryl group, a pyrenyl group, a phenanthrene group, a methylphenyl group, a dimethylphenyl group, a biphenyl group and a fluorenyl group. Group is preferable.

The number of carbon atoms in the heteroaryl group (monovalent aromatic heterocyclic group) is not particularly limited, but is preferably 3 to 30, and more preferably 3 to 18, from the viewpoint of more excellent effects of the present invention. The heteroaryl group may have a substituent W described later.

The heteroaryl group includes a heteroatom in addition to a carbon atom and a hydrogen atom. Examples of the heteroatom include a nitrogen atom, a sulfur atom, an oxygen atom, a selenium atom, a tellurium atom, a phosphorus atom, a silicon atom, And a nitrogen atom, a sulfur atom, or an oxygen atom is preferable. The number of heteroatoms contained in the heteroaryl group is not particularly limited and is generally about 1 to 10, preferably 1 to 4.

The number of the heteroaryl group to be reduced is not particularly limited, but is preferably 3 to 8 membered rings, more preferably 5 to 7 membered rings, and particularly preferably 5 to 6 membered rings.

The heteroaryl group includes, for example, a pyridyl group, a quinolyl group, an isoquinolyl group, an acridine group, a phenanthridinyl group, a pyrimidinyl group, a pyrimidinyl group, a pyrazinyl group, a quinoxalinyl group, a pyrimidinyl group, A thiazolidine group, a thiazolidine group, a benzothiazolyl group, an imidazolyl group, a benzoimidazolyl group, a pyrazolyl group, an indazolyl group, a pyrazolyl group, An isothiazolyl group, an isothiazolyl group, an oxadiazolyl group, a thiadiazolyl group, a triazolyl group, a tetrazolyl group, a furyl group, a benzofuryl group, a cy Dienes, benzothienyl groups, thienothienyl groups, dibenzofuryl groups, dibenzothienyl groups, pyrrolyl groups, indolyl groups, imidazopyridinyl groups, and carbazolyl groups.

The number of carbon atoms in the alkenyl group is not particularly limited, but is preferably from 2 to 10, and more preferably from 2 to 6, from the viewpoint of more excellent effects of the present invention. The alkenyl group may be any of linear, branched, and cyclic structures and may have a substituent W described later.

Preferable examples of the alkenyl group include a vinyl group and a 1-propenyl group.

The substituent W in the present specification will be described.

Examples of the substituent W include a halogen atom, an alkyl group (including a cycloalkyl group, a bicycloalkyl group and a tricycloalkyl group), an alkenyl group (including a cycloalkenyl group and a bicycloalkenyl group), an alkynyl group, (Which may be a heterocyclic group), a cyano group, a hydroxyl group, a nitro group, a carboxy group, an alkoxy group, an aryloxy group, a silyloxy group, a heterocyclic oxy group, an acyloxy group, a carbamoyloxy group, An aryloxycarbonyloxy group, an amino group (including an anilino group), an ammonio group, an acylamino group, an aminocarbonylamino group, an alkoxycarbonylamino group, an aryloxycarbonylamino group, a sulfamoylamino group, an alkylsulfonylamino group, An alkylsulfinyl group, an alkylsulfinyl group, an alkylsulfinyl group, an acyl group, an arylsulfinyl group, an arylsulfinyl group, an arylsulfinyl group, an arylsulfinyl group, an arylsulfinyl group, A heterocyclic group, a phosphinyl group, a phosphinyloxy group, a phosphinylamino group, a phosphono group, a silyl group, a hydrazino group, a ureido group, an alkoxycarbonyl group, a carbamoyl group, an aryl or a heterocyclic azo group, (-B (OH) ₂ ), a phosphato group (-OPO (OH) ₂ ), a sulfato group (-OSO ₃ H), and other known substituents.

The details of the substituent W are described in paragraph [0023] of Japanese Patent Laid-Open No. 2007-234651.

Ar ¹ and Ar ² each independently represent an arylene group which may have a substituent or a heteroarylene group which may have a substituent.

The number of carbon atoms in the arylene group is not particularly limited, but is preferably from 6 to 30, and more preferably from 6 to 20, from the viewpoint of more excellent effects of the present invention.

Examples of the arylene group include a phenylene group, a biphenylene group, a terphenylene group, a naphthylene group, an anthrylene group, a phenanthrylene group, a pyranediyl group, a perylenediyl group, a fluorenediyl group, A benzoanthracene diester group, a benzophenanthrene diester group, and the like.

The number of carbon atoms in the heteroarylene group is not particularly limited, but is preferably from 1 to 20, and more preferably from 2 to 12, from the viewpoint of more excellent effects of the present invention.

The heteroarylene group includes, for example, a pyridyl group, a quinolylene group, an isoquinolylene group, an acridinediyl group, a phenanthridinediyl group, a pyrazinediyl group, a quinoxalinediyl group, a pyrimidinediyl group, A thiazolidinyl group, a pyrazolodyryl group, an oxadiazole diyl group, a triazolediyl group, a furylene group, a thienylene group, a pyrrolylthio group, an indolylthio group, and a carbazolylthio group.

The arylene group and the heteroarylene group may have a substituent. As the substituent, the substituent W may be mentioned.

At least one of Ar ¹ and R ¹ , Ar ¹ and R ² , R ¹ and R ² , Ar ² and R ³ , Ar ² and R ^4, and R ³ and R ⁴ is bonded to each other to form a ring . In addition, at the time of bonding, Ar ¹ and R ¹ , Ar ¹ and R ² , R ¹ and R ² , Ar ² and R ³ , Ar ² and R ⁴ , and R ³ and R ⁴ may be bonded to each other directly or through a linking group And it is more preferable to form a ring by direct bonding or form a ring through an alkylene group since the effect of the present invention is more excellent.

The structure of the linking group is not particularly limited, and examples thereof include an oxygen atom, a sulfur atom, an alkylene group, a silylene group, an alkenylene group, a cycloalkylene group, a cycloalkylene group, an arylene group, a divalent heterocyclic group, Or a combination thereof, and these may further have a substituent. The alkylene group is preferably an alkylene group, a silylene group, an alkenylene group, a cycloalkylene group, a cycloalkylenerene group, or an arylene group, and more preferably an alkylene group.

The structure of the ring to be formed is not particularly limited and includes, for example, an aliphatic ring which may have a hetero atom, an aromatic ring which may have a hetero atom, and the like. An aromatic ring which may be substituted.

At least one of Ar ¹ and R ¹ , Ar ¹ and R ² , and R ¹ and R ² is bonded to each other to form a ring, and Ar ² and R ³ , Ar ² and R ^4, and at least one of R ³ and R ⁴ are preferably bonded to each other to form a ring, and Ar ¹ and R ¹ , and Ar ² and R ³ are bonded to each other to form a ring Is more preferable.

A ¹ represents any one group selected from the group consisting of groups represented by the general formula (2-1) to groups represented by the general formula (2-3). Among them, the group represented by the general formula (2-1) is preferable in that the effect of the present invention is more excellent.

(3)

In the general formulas (2-1) to (2-3), X ¹ and X ² each independently represent an oxygen atom, a sulfur atom, a selenium atom, ═NR ^a1 or ═CR ^a2 R ^a3 . Among them, an oxygen atom or a sulfur atom is preferable, and an oxygen atom is more preferable because the effect of the present invention is more excellent.

R ^a1 represents a hydrogen atom or a substituent. As the substituent, the above-mentioned substituent W can be mentioned, and among them, an alkyl group or an aryl group is preferable from the viewpoint of the effect of the present invention being more excellent.

R ^a2 and R ^a3 each independently represent a cyano group, a carbonyl group or an alkoxycarbonyl group.

Y ¹ and Y ² each independently represent an oxygen atom, a sulfur atom, a selenium atom,> NR ^b1 ,> CR ^b2 R ^b3 , or> SiR ^b4 R ^b5 . Among them, an oxygen atom or a sulfur atom is preferable, and an oxygen atom is more preferable because the effect of the present invention is more excellent.

R ^b1 to R ^b5 each independently represent a hydrogen atom or a substituent. As the substituent, there can be mentioned the above substituent W, and among them, an alkyl group is preferable because the effect of the present invention is more excellent.

* 1 and * 2 in the general formula (1) indicate that they are bonded to * 1 and * 2 in the general formulas (2-1) to (2-3), respectively. More specifically, examples of structural formulas when the groups represented by the general formulas (2-1) to (2-3) are introduced into A ¹ in the general formula (1) are shown below.

[Chemical Formula 4]

One of the preferable embodiments of the compound represented by the general formula (1) is a compound represented by the following general formula (X).

[Chemical Formula 5]

In the formula (X), R ¹¹ to R ¹⁴ , R ²¹ to R ²⁵ , R ³¹ to R ³⁵ , R ⁴¹ to R ⁴⁴ , R ⁵¹ to R ⁵⁵ , and R ⁶¹ to R ⁶⁵ each independently represent hydrogen An atom, or a substituent. As the substituent, for example, the above-mentioned substituent W can be mentioned.

At least one of R ¹² and R ²¹ , R ²⁵ and R ³¹ , R ¹³ and R ³⁵ , R ⁴² and R ⁵¹ , R ⁵⁵ and R ⁶¹ , and R ⁴³ and R ⁶⁵ may be bonded to each other to form a ring do. Among them, R ¹² and R ²¹ , R ²⁵ and R ³¹ , and at least one of R ¹³ and R ³⁵ , R ⁴² and R ⁵¹ , R ⁵⁵ and R ⁶¹ , and R It is preferable that at least one of R ⁴³ and R ⁶⁵ is bonded to each other to form a ring, and it is more preferable that R ¹² and R ²¹ , R ⁴² and R ⁵¹ are bonded to each other to form a ring.

In addition, at the time of bonding, as described above, they may be bonded to each other directly or via a linking group to form a ring, and the types of linking groups are as described above.

The definition of A ¹ is as described above.

Hereinafter, the compound represented by the general formula (1) is exemplified. In the following specific examples, Me represents methyl.

[Chemical Formula 6]

(7)

[Chemical Formula 8]

[Chemical Formula 9]

The dipole moment of the compound represented by the general formula (1) is not particularly limited, but is preferably 1 D or less, more preferably 0.5 D or less, from the viewpoint of further improving the effect of the present invention.

The above-mentioned dipole moment can be obtained by calculation. Specifically, it can be obtained by the molecular orbital calculation software Gaussian 09 (manufactured by Gaussian) using the base function 6-31G (d) in the B3LYP method.

It is preferable that the compound represented by the general formula (1) has an absorption maximum in the ultraviolet visible absorption spectrum of 400 nm or more and less than 720 nm. The peak wavelength (absorption maximum wavelength) of the absorption spectrum is more preferably 450 nm or more and 700 nm or less, more preferably 480 nm or more and 650 nm or less, from the viewpoint of absorbing light in the visible region, particularly light in the G region (500-600 nm) And particularly preferably from 500 nm to 600 nm.

The absorption maximum wavelength of the compound represented by the general formula (1) can be measured by using a chloroform solution of the compound using UV-2550 manufactured by Shimadzu Corporation. The concentration of the chloroform solution is preferably 5 × 10 ^-5 to 1 × 10 ^-7 mol / l, more preferably 3 × 10 ^-5 to 2 × 10 ^-6 mol / l, more preferably 2 × 10 ^-5 to 5 X 10 < ^-6 > mol / l is particularly preferable.

The compound represented by the general formula (1) preferably has an absorption maximum at wavelengths of 400 nm or more and less than 720 nm in the ultraviolet visible absorption spectrum and has a molar extinction coefficient at the maximum absorption wavelength of 10000 mol ^{-1 -1} · cm ^-1 or more. In order to reduce the film thickness of the photoelectric conversion film to obtain a device with high charge collection efficiency, high-speed responsiveness and high sensitivity characteristics, a material having a high molar extinction coefficient is preferable. The molar extinction coefficient of the compound represented by the general formula (1) is more preferably 30000 mol ^-1 · 1 · cm ^-1 or more, and still more preferably 50000 mol ^-1 · 1 · cm ^-1 or more. The molar extinction coefficient of the compound represented by the general formula (1) is measured with a chloroform solution.

The larger the difference between the melting point and the deposition temperature (melting point-deposition temperature) is, the more difficult is the decomposition of the compound represented by the general formula (1) at the time of deposition, and the deposition rate can be increased by applying a high temperature. The difference between the melting point and the deposition temperature (melting point-deposition temperature) is preferably 30 占 폚 or higher, more preferably 45 占 폚 or higher, and even more preferably 60 占 폚 or higher.

The molecular weight of the compound represented by the general formula (1) is preferably 300 to 1500, more preferably 500 to 1000, and particularly preferably less than 500 and less than 850 from the viewpoint of the effect of the present invention being more excellent. If the molecular weight of the compound is 1500 or less, the deposition temperature is not increased and the decomposition of the compound is difficult to occur. If the molecular weight of the compound is 300 or more, the glass transition point of the vapor-deposited film is not lowered, and the heat resistance of the device is hardly lowered.

The glass transition temperature (Tg) of the compound represented by the general formula (1) is preferably 95 ° C or higher, more preferably 110 ° C or higher, more preferably 135 ° C or higher, particularly preferably 150 ° C or higher, Or more. The higher the glass transition point, the better the heat resistance of the device is.

The compound represented by the general formula (1) is particularly useful as a material of a photoelectric conversion film used in an image pickup device, a photosensor, or a photo cell. Further, usually, the compound represented by the general formula (1) functions as an organic p-type compound in the photoelectric conversion film. It may also be used as a coloring material, a liquid crystal material, an organic semiconductor material, an organic light emitting device material, a charge transport material, a medicine material, a fluorescent diagnostic material, and the like for other purposes.

(Other materials)

The photoelectric conversion film may further contain a photoelectric conversion material of an organic p-type compound or an organic n-type compound.

Organic p-type compounds (organic p-type semiconductors) are donor organic semiconductors (compounds), usually represented by hole-transporting organic compounds, and are organic compounds having a property of donating electrons. More specifically, it refers to an organic compound having a smaller ionization potential when two organic materials are used in contact with each other. Therefore, any organic compound can be used as long as the donor organic compound is an organic compound having an electron donor. For example, a triarylamine compound, a benzidine compound, a pyrazoline compound, a styrylamine compound, a hydrazone compound, a triphenylmethane compound, a carbazole compound and the like can be used.

Organic n-type compounds (organic n-type semiconductors) are acceptor organic semiconductors, mainly represented by electron-transporting organic compounds, and are organic compounds having a property of accepting electrons. More specifically, it refers to an organic compound having a larger electron affinity when two organic compounds are used in contact with each other. Therefore, any organic compound can be used as long as the acceptor organic semiconductor is an organic compound having electron acceptability. Preferably, fullerene or a fullerene derivative, a condensed aromatic carbon ring compound (a naphthalene derivative, an anthracene derivative, a phenanthrene derivative, a tetracene derivative, a pyrene derivative, a perylene derivative or a fluoranthene derivative) (Such as pyridine, pyrazine, pyrimidine, pyridazine, triazine, quinoline, quinoxaline, quinazoline, phthalazine, cinnoline, isoquinoline, pteridine , Acridine, phenazine, phenanthroline, tetrazole, pyrazole, imidazole, thiazole, oxazole, indazole, benzoimidazole, benzotriazole, benzoxazole, benzothiazole, carbazole, purine , Triazalopyridazine, triazolepyrimidine, tetrazaine, oxadiazole, imidazopyridine, pyrrolopyridine, thiadiazolopyridine, dibenzoazepine, tribenzoazepine, etc.), polyarylene anger Water, a fluorene compound, a cyclopentadiene compound, a silyl compound, a nitrogen-containing heterocyclic compound and the like can be mentioned a metal complex having as a ligand.

When the organic n-type compound is used in an embodiment as shown in Fig. 3, which will be described later, a fullerene type selected from the group consisting of fullerene and fullerene derivatives is preferable. The fullerene includes 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 , And a fullerene derivative refers to a compound to which a substituent is added. The substituent is preferably an alkyl group, an aryl group or a heterocyclic group. As the fullerene derivative, a compound described in JP-A-2007-123707 is preferable.

2, the organic n-type compound is preferably colorless, or has an absorption maximum wavelength and / or absorption waveform close to that of the organic p-type compound, and specific values include absorption maximum wavelengths of 400 nm or less, Or 500 nm or more and 600 nm or less. Any compound having the characteristics of the above-mentioned organic n-type compound and being suitable for absorption can be used, and examples thereof include compounds described in [0016] to [0019] of US2013-0112947.

The photoelectric conversion film preferably has a bulk hetero structure in which the compound represented by the general formula (1) and the organic n-type compound are mixed. The bulk hetero structure is a layer in which an organic p-type compound and an organic n-type compound are mixed and dispersed in the photoelectric conversion film, and can be formed by any of a wet method and a dry method, but is preferably formed by a co-evaporation method. By including the heterojunction structure, it is possible to improve the photoelectric conversion efficiency of the photoelectric conversion film by compensating for the drawback that the carrier diffusion length of the photoelectric conversion film is short. The bulk heterojunction structure is described in detail in [0013] to [0014] of Japanese Laid-Open Patent Publication No. 2005-303266.

From the viewpoint of the response of the photoelectric conversion element, the content of the organic n-type compound relative to the total content of the compound represented by the general formula (1) and the organic n-type compound (= (Film thickness in terms of a single layer conversion of the compound represented by the formula (1) + film thickness in terms of a single layer conversion of the organic n-type compound) is preferably 50% by volume or more, and more preferably 55% by volume or more when the organic n-type compound is fullerene And more preferably at least 65% by volume. The upper limit is not particularly limited, but is preferably 95% by volume or less, and more preferably 90% by volume or less. When the organic n-type compound is a compound other than fullerene, the content is preferably 20 vol% or more and 80 vol% or less, more preferably 30 vol% or more and 70 vol% or less, more preferably 40 vol% or more and 60 vol% Or less.

The compound represented by the general formula (1) of the present invention and the photoelectric conversion film containing the organic n-type compound are non-luminescent films and have characteristics different from those of the organic electroluminescent device (OLED). The non-luminescent film is a film having a luminescence quantum efficiency of 1% or less, more preferably 0.5% or less, and more preferably 0.1% or less.

(Film forming method)

The photoelectric conversion film can be mainly formed by a dry film formation method. Specific examples of the dry film forming method include a physical vapor deposition method such as a vapor deposition method (in particular, a vacuum vapor deposition method), a sputtering method, an ion plating method and an MBE method, or a CVD method such as plasma polymerization. Preferably, a vacuum deposition method is used. In the case of forming the film by the vacuum evaporation method, the manufacturing conditions such as the degree of vacuum and the deposition temperature can be set according to an ordinary method.

The thickness of the photoelectric conversion film 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 500 nm or less. When the thickness 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 can be obtained.

[electrode]

The electrodes (the upper electrode (transparent conductive film) 15 and the lower electrode (conductive film) 11) are made of a conductive material. As the conductive material, a metal, an alloy, a metal oxide, an electrically conductive compound, a mixture thereof, or the like can be used.

Since the light is incident from the upper electrode 15, it is preferable that the upper electrode 15 is sufficiently transparent to the light to be detected. 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, transparent conductive metal oxides are preferred from the viewpoints of high conductivity and transparency.

In general, when the conductive film is made thinner than a predetermined range, the resistance value is abruptly 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 (transparent conductive film) 15, 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 film and increases the photoelectric conversion ability. The film thickness of the upper electrode 15 is preferably 5 to 100 nm, more preferably 5 to 20 nm, in consideration of suppression of leak current, increase in the resistance value of the thin film, and increase in transmittance, desirable.

The lower electrode 11 may be made to have transparency depending on the application, or may be made of a material that reflects light without having 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 method of forming the electrode is not particularly limited and may be appropriately selected depending on the 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.

[Charge blocking film: electron blocking film, hole blocking film]

The photoelectric conversion element of the present invention may have a charge blocking film. By having this film, the characteristics (photoelectric conversion efficiency, response speed, etc.) of the obtained photoelectric conversion element are more excellent. Examples of the charge blocking film include an electron blocking film and a hole blocking film. Hereinafter, each of the films will be described in detail.

(Electron blocking film)

As the electron blocking film, 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), and the like; oxazole, oxadiazole, triazole, imidazole, imidazolone, stilbene derivatives, tetrahydroimide 4,4 ', 4 "-tris (N- (3-methylphenyl) N-phenylamino) triphenylamine (m-MTDATA), porphyrin, tetraphenylporphyrin copper There may be mentioned porphyrin compounds such as talloxanthracene, talophenylene, copper phthalocyanine and titanium phthalocyanine oxide, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, Diamine derivatives, arylamine derivatives, amino substituted chalcone derivatives, oxazole derivatives, styryl anthracene derivatives, fluorene derivatives, A polymer such as phenylene vinylene, fluorene, carbazole, indole, pyrene, pyrrole, picoline, thiophene, acetylene, diacetylene, and the like can be used as the polymer material, It is possible to use a compound having a sufficient hole-transporting property even if it is not an electron-donating compound. Specifically, JP-A-2008-72090 [0083] to [0089] The compounds described in [0043] to [0063] of JP-A-2011-176259, [0121] to [0148] of JP-A No. 2011-228614 and [0108] to [0156] of JP-A No. 2011-228615 are preferable.

Further, the electron blocking film may be composed of a plurality of films.

As the electron blocking film, an inorganic material may be used. Generally, since the inorganic material has a larger dielectric constant than that of the organic material, a large amount of voltage is applied to the photoelectric conversion film when used in the electron blocking film, and the photoelectric conversion efficiency can be increased. Examples of the material that can be an electron blocking film include calcium oxide, chromium oxide, chromium oxide, manganese oxide, cobalt oxide, nickel oxide, copper oxide, gallium oxide copper, strontium oxide, niobium oxide, molybdenum oxide, Indium copper, indium oxide, and iridium oxide. When the electron blocking film is a single layer, the layer 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.

(Hole blocking film)

As the hole blocking film, 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. Specifically, the compounds described in [0073] to [0078] of JP-A No. 2008-72090 are preferable.

The method for producing the charge blocking film is not particularly limited, and the film can be formed by a dry film forming method or a wet film forming method. As the dry film formation method, a vapor deposition method, a sputtering method, or the like can be used. The deposition may be physical vapor deposition (PVD) or chemical vapor deposition (CVD), and physical vapor deposition such as vacuum deposition is preferable. As the wet film formation method, an ink jet method, a spray method, a nozzle printing method, a spin coat method, a dip coat method, a cast method, a die coat method, a roll coat method, a bar coat method, a gravure coat method, The ink jet method is preferable.

The thickness of the charge blocking film (electron blocking film and positive hole blocking film) is preferably 10 to 200 nm, more preferably 30 to 150 nm, and particularly preferably 50 to 100 nm. If the thickness is too thin, the dark current suppressing effect is deteriorated. If the thickness is too large, the photoelectric conversion efficiency is lowered.

[Board]

The photoelectric conversion element may further include a substrate. The type of the substrate to be used is not particularly limited, and a semiconductor substrate, a glass substrate, or a plastic substrate can be used.

The position of the substrate is not particularly limited, but usually a conductive film, a photoelectric conversion film, and a transparent conductive film are laminated in this order on a substrate.

[Sealing layer]

The photoelectric conversion element may further include a sealing layer. The photoelectric conversion material may remarkably deteriorate in performance due to the presence of a deterioration factor such as water molecules, and may be used in a variety of applications including ceramics such as dense metal oxides, metal nitrides, metal nitrides, and diamond-like carbon (DLC) It is possible to prevent the deterioration by covering and sealing the entire photoelectric conversion film.

As the sealing layer, materials may be selected and manufactured according to the description of paragraphs [0210] to [0215] of Japanese Laid-Open Patent Publication No. 2011-082508.

[Optical sensor]

Examples of the application of the photoelectric conversion element include a photoelectric cell and an optical sensor. The photoelectric conversion element of the present invention is preferably used as an optical sensor. As the optical sensor, it is preferable that the photoelectric conversion element is used singly or in the form of a line sensor in which the photoelectric conversion elements are arranged in a straight line or a two-dimensional sensor arranged on a plane. In the photoelectric conversion element of the present invention, in a line sensor, optical image information is converted into an electric signal by using an optical system and a driving unit such as a scanner, and in a two-dimensional sensor, So as to function as an imaging element.

Since a photovoltaic cell is a power generation device, the efficiency of converting light energy into electric energy is important, but dark current, which is a current in a dark place, is not a functional problem. Further, there is no need for a subsequent heating step such as the installation of a color filter. Since the optical sensor is important for converting the contrast signal into an electrical signal with high precision, the efficiency of converting the light amount to the current is also an important performance. However, since dark signals output noise, low dark current is required .

[Image pickup device]

Next, a configuration example of an image pickup device having the photoelectric conversion element 10a will be described.

In the constitution examples described below, members having the same structure and action as those of members already described or the like are denoted by the same reference numerals or signs in the drawings, thereby simplifying or omitting the description.

An image pickup element is an element for converting optical information of an image into an electric signal, and a plurality of photoelectric conversion elements are arranged in a matrix on the same plane, and an optical signal is converted into an electric signal in each photoelectric conversion element And outputs the electric signal sequentially out of the image pickup element for each pixel. Thus, one photoelectric conversion element and one or more transistors per pixel are formed.

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.

This image pickup device has a plurality of photoelectric conversion elements each having a configuration as shown in Fig. 1 and a circuit board on which a readout circuit for reading signals corresponding to charges generated in the photoelectric conversion film of each photoelectric conversion element is formed, And a plurality of photoelectric conversion elements are arranged in a one-dimensional or two-dimensional shape on the same surface on the upper side.

3 includes a substrate 101, an insulating layer 102, a connection electrode 103, a pixel electrode (lower electrode) 104, a connection portion 105, a connection portion A buffer layer 109, a sealing layer 110, a color filter (CF) 111, a barrier rib 112, a photoelectric conversion film 107, a counter electrode (upper electrode) A light-shielding layer 113, a protective layer 114, a counter electrode voltage supply section 115, and a readout circuit 116. The light-

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

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 photoelectric conversion film 107 is a layer common to all of the photoelectric conversion elements provided over the plurality of pixel electrodes 104. [

The counter electrode 108 is one electrode common to all the photoelectric conversion elements provided on the photoelectric conversion film 107. The counter electrode 108 is formed over the connection electrode 103 disposed outside the photoelectric conversion film 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 boosting 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 a signal corresponding to the charge collected at the corresponding pixel electrode 104. [ The reading circuit 116 is composed of, for example, a CCD, a CMOS circuit, a TFT circuit, or the like, 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 in a region other than the region where the color filter 111 and the barrier rib 112 are provided on the sealing layer 110 and prevents light from being incident on the photoelectric conversion film 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 photoelectric conversion film 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 outputted to the outside of the image pickup device 100 by the reading 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 square lattice form.

Next, on the plurality of pixel electrodes 104, the photoelectric conversion film 107 is formed by, for example, a vacuum heating evaporation method. Next, the counter electrode 108 is formed on the photoelectric conversion film 107 under vacuum, for example, by the sputtering method. Next, a buffer layer 109 and a sealing layer 110 are formed on the counter electrode 108 in this order by, for example, vacuum evaporation 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. [

Even in the method of manufacturing the image pickup device 100, a step of placing the image pickup device 100 under the non-vacuum condition during the process of forming the photoelectric conversion film 107 and the step of forming the sealing layer 110 may be added , Degradation of performance of a plurality of photoelectric conversion elements can be prevented. By adding this step, deterioration of the performance of the image pickup device 100 can be prevented, and manufacturing cost can be suppressed.

Example

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

(Synthesis of Compound D-1)

Compound D-1 was synthesized according to the following scheme.

[Chemical formula 10]

The compound D-2, the compound D-4, the compound D-5, the compound D-7, the compound D-11, the compound D-15 to the compound D-17, 20, the compound D-24, the compound D-30, the compound D-31, the compound D-40, the compound D-43, the compound D- D-1, and a known method. In addition, the numbers of the compounds correspond to the above-mentioned exemplified numbers of the compounds represented by the general formula (1).

Hereinafter, the compounds used in the present examples and comparative examples are collectively shown.

(11)

[Chemical Formula 12]

[Chemical Formula 13]

[Chemical Formula 14]

≪ Fabrication of photoelectric conversion element 1 (element assumed in the embodiment of Fig. 3)

As the photoelectric conversion element used in the embodiment in which the photoelectric conversion film is the panchromatic light as shown in Fig. 3, the photoelectric conversion element of the form of Fig. 1 (a) was manufactured under the following conditions. Here, the photoelectric conversion element is composed of the lower electrode 11, the electron blocking film 16A, the photoelectric conversion film 12, and the upper electrode 15.

Specifically, amorphous ITO is formed on a glass substrate by a sputtering method to form the lower electrode 11 (thickness: 30 nm), and the following compound (EB-1) is formed on the lower electrode 11 And the film was formed by a vacuum heating deposition method to form an electron blocking film 16A (thickness: 100 nm). The compound D-1 and fullerene (C ₆₀ ) were vapor-deposited by vacuum evaporation so as to have a thickness of 120 nm and 280 nm in terms of a single layer, respectively, on the electron blocking film 16A while the temperature of the substrate was controlled at 25 占 폚 So as to form a photoelectric conversion film 12. Further, amorphous ITO was formed on the photoelectric conversion film 12 by sputtering to form the upper electrode 15 (transparent conductive film) (thickness: 10 nm). An SiO 2 film was formed as a sealing layer on the upper electrode 15 by thermal evaporation and then an aluminum oxide (Al ₂ O ₃ ) layer was formed thereon by the ALCVD method to produce a photoelectric conversion element.

Further, each photoelectric conversion element was produced in the same manner as above except that the compound shown in Table 1 described below was used in place of the compound D-1. The evaluation results correspond to Table 1.

[Chemical Formula 15]

≪ Fabrication of photoelectric conversion element 2 (element assumed in the embodiment of Fig. 2)

As a G-light selective photoelectric conversion element for use in the hybrid type embodiment shown in Fig. 2, a photoelectric conversion element of the type shown in Fig. 1 (a) was produced under the following conditions. Here, the photoelectric conversion element is composed of the lower electrode 11, the electron blocking film 16A, the photoelectric conversion film 12, and the upper electrode 15.

Specifically, amorphous ITO is deposited on a glass substrate by a sputtering method to form the lower electrode 11 (thickness: 30 nm), and the compound (EB-1) is formed on the lower electrode 11 And the film was formed by a vacuum heating deposition method to form an electron blocking film 16A (thickness: 100 nm). The compound D-1 and the compound N-1 shown below were converted into a 100 nm thick film and 100 nm thick, respectively, in terms of a single layer, on the electron blocking film 16A under the condition of controlling the temperature of the substrate at 25 캜. So as to form a photoelectric conversion film 12. Further, amorphous ITO was formed on the photoelectric conversion film 12 by sputtering to form the upper electrode 15 (transparent conductive film) (thickness: 10 nm). An SiO 2 film was formed as a sealing layer on the upper electrode 15 by thermal evaporation and then an aluminum oxide (Al ₂ O ₃ ) layer was formed thereon by the ALCVD method to produce a photoelectric conversion element.

Further, each photoelectric conversion element was produced in the same manner as above except that the compound shown in Table 2 described below was used in place of the compound D-1. The evaluation results correspond to Table 2.

[Chemical Formula 16]

<Verification of device operation (measurement of dark current)>

And it was confirmed whether or not each of the obtained elements would function as a photoelectric conversion element.

When a voltage was applied to the lower electrode and the upper electrode of each of the obtained devices (Examples 1 to 20 and Comparative Examples 1 to 4) so as to have an electric field intensity of 2.5 x 10 ⁵ V / cm, ² or less, but a current of 10 μA / cm ² or more appeared in a bright place, confirming that the photoelectric conversion element functions.

&Lt; Response speed evaluation (response evaluation) >

The responsiveness of each of the obtained photoelectric conversion elements was evaluated.

Specifically, a voltage was applied to the photoelectric conversion element so as to have an electric field intensity of 2.0 × 10 ⁵ V / cm. Thereafter, the LED is momentarily turned on to irradiate light from the upper electrode (transparent conductive film) side, and the optical current at that time is measured with an oscilloscope to measure the relative response speed (rise time from 0 to 98% signal intensity) did. In measuring the response speed of each element, light was incident from the upper electrode (transparent conductive film) side.

The calculation method of the response speed (phase value) is shown below. The response speed (phase value) of Example X (or Comparative Example X) = 0 to 98% in Example X (or Comparative Example X) for Examples 1 to 17 and Comparative Examples 1 and 2, Rise time to signal intensity / rise time from 0 to 98% signal intensity in embodiment 1]. The response speed (phase value) of Example X (or Comparative Example X) = 0 to 98% in Example X (or Comparative Example X) for Examples 18 to 20 and Comparative Examples 3 and 4, Rise time to signal intensity / rise time from 0 to 98% signal intensity in Example 18].

The response speed (phase value) is preferably 15 or less in practical use, more preferably 5 or less, and more preferably 2 or less.

&Lt; Evaluation of manufacturing aptitude &

In order to compare the suitability for production of the photoelectric conversion elements in each of the examples and the comparative examples, the degradation of the responsiveness after continuous deposition for 5 hours was examined using each photoelectric conversion material. Specifically, evaluation was made as follows.

First, the deposition rate was fixed at 3.0 ANGSTROM / sec and continuous deposition was carried out. A photoelectric conversion element was fabricated in the same manner as in the above-described production of the above-described photoelectric conversion element, immediately after the start of deposition and after 5 hours from the start of deposition . Then, the rise time from 0 to 98% signal intensity was evaluated for each of the "devices fabricated immediately after deposition start" and "devices fabricated 5 hours after the start of deposition" in the same order as the evaluation of the above- , And the lowering of the responsiveness was investigated as follows.

Decrease in response = (rise time of device manufactured 5 hours after deposition start) / (rise time of device manufactured immediately after deposition start)

The results are shown in Table 1. "A" indicates that the response is less than 1.1, "B" indicates that the response is less than 1.2 and less than 1.5, "C" indicates that the response is less than 1.5 and less than 3.0, and "D" . The results are shown in Table 1. In practice, "AA", "A" or "B" is preferable, "AA" or "A" is more preferable, and "AA" is more preferable.

"Molecular weight" in Table 1 indicates the molecular weight of the photoelectric conversion material used in each of the Examples and Comparative Examples.

The term "dipole moment" indicates the dipole moment of the photoelectric conversion material used in each of the examples and the comparative examples.

[Table 1]

[Table 2]

As shown in Table 1, it was confirmed that the photoelectric conversion element of the present invention exhibits excellent response and manufacturability.

Among them, as can be seen from the comparison of Example 1, Example 13, and Example 14, it was confirmed that when X ¹ and X ² were both oxygen atoms, the response was better.

Further, as can be seen from the comparison between Example 5 and Example 15, it was confirmed that when the group represented by the general formula (2-1) was used, the response was better.

As can be seen from the comparison between Example 5 and Example 8, when Ar ¹ and R ¹ , and Ar ² and R ³ , when bonded to each other to form a ring, are more excellent in response and manufacturing suitability .

As can be seen from the comparison of Example 12 with other embodiments, the groups forming a ring in R ¹ , R ² , R ³ and R ⁴ may be an aryl group which may have a substituent or a heteroatom which may have a substituent In the case of an aryl group, it was confirmed that the response and manufacturing suitability were better.

As can be seen from the comparison of Example 1, Example 5, and Example 10, Ar ¹ and R ¹ , Ar ¹ and R ² , R ¹ and R ² , Ar ² and R ³ , Ar ² and R ⁴ and at least one of R ³ and R ⁴ are bonded to each other to form a ring, it is confirmed that when they are bonded to each other directly or via an alkylene group, the response and the manufacturability are better.

From the comparison of Example 5 and Example 11, it was confirmed that when R ¹ , R ² , R ³ , and R ⁴ are aryl groups, the response and manufacturing suitability are better.

As can be seen from comparison between Example 17 and other embodiments, Ar ¹ and R ¹ , Ar ¹ and R ² , and at least one of R ¹ and R ² , and Ar ² and R ³ , Ar ² and R ⁴ And at least one of R &lt; ³ &gt; and R &lt; ⁴ &gt; are bonded to each other to form a ring, it was confirmed that the response and the manufacturability were better.

As can be seen from comparison between Examples 9, 12, 14 and 17 and other Examples, when the molecular weight of the compound is 500 or more and less than 850, and the dipole moment of the compound is 1D or less, .

From the results of Examples 18 to 20, the same tendency was also confirmed when the embodiment in the hybrid type was assumed and the organic n-type compound (n-type semiconductor compound) was changed.

On the other hand, it was confirmed that when RD-1 used in the example of Patent Document 1 was used (corresponding to Comparative Example 1) and when another compound (RD-2) was used, the responsiveness and manufacturability were poor. The same tendency was confirmed even when the organic n-type compound (n-type semiconductor compound) was changed.

<Fabrication of imaging device>

An imaging device identical to that shown in Fig. 3 was produced. That is, a film of amorphous TiN 30 nm is formed on the CMOS substrate by sputtering and then patterned so as to have one pixel on each photodiode PD on the CMOS substrate by photolithography to form a lower electrode, After the film formation, the films were produced in the same manner as in Examples 1 to 17 and Comparative Examples 1 and 2. The evaluation was also made in the same manner, and the same results as those in Table 1 were obtained, indicating that the imaging device is suitable for manufacturing and exhibits excellent performance.

10a, 10b photoelectric conversion element
11 Lower electrode (conductive film)
12 photoelectric conversion film
15 upper electrode (transparent conductive film)
16A electron blocking membrane
16B hole blocking film
100 pixel separation type image pickup element
101 substrate
102 insulating layer
103 connecting electrode
104 pixel electrode (lower electrode)
105 connection
106 connection
107 photoelectric conversion film
108 counter electrode (upper electrode)
109 buffer layer
110 sealing layer
111 Color Filter (CF)
112 barrier
113 Shading layer
114 protective layer
115 counter electrode voltage supply unit
116 Readout circuit
200 photoelectric conversion element (hybrid photoelectric conversion element)
201 inorganic photoelectric conversion film
202 n-type well
203 p-type well
204 n-type well
205 p-type silicon substrate
207 insulating layer
208 pixel electrode
209 Organic photoelectric conversion film
210 common electrode
211 Shield
212 Electronic blocking membrane

Claims (12)

As a photoelectric conversion element having a conductive film, a photoelectric conversion film containing a photoelectric conversion material, and a transparent conductive film in this order,
Wherein the photoelectric conversion material comprises a compound represented by the general formula (1).
[Chemical Formula 1]

(2)

In the general formula (1), R ¹ to R ⁴ each independently represent an alkyl group, an aryl group which may have a substituent, a heteroaryl group which may have a substituent, or an alkenyl group which may have a substituent. Ar ¹ and Ar ² each independently represent an arylene group which may have a substituent or a heteroarylene group which may have a substituent. At least one of Ar ¹ and R ¹ , Ar ¹ and R ² , R ¹ and R ² , Ar ² and R ³ , Ar ² and R ^4, and R ³ and R ⁴ is bonded to each other to form a ring . A ¹ represents any one group selected from the group consisting of groups represented by the general formula (2-1) to groups represented by the general formula (2-3). In the general formulas (2-1) to (2-3), X ¹ and X ² each independently represent an oxygen atom, a sulfur atom, a selenium atom, ═NR ^a1 or ═CR ^a2 R ^a3 . R ^a1 represents a hydrogen atom or a substituent, and R ^a2 and R ^a3 each independently represent a cyano group, a carbonyl group or an alkoxycarbonyl group. Y ¹ and Y ² each independently represent an oxygen atom, a sulfur atom, a selenium atom,> NR ^b1 ,> CR ^b2 R ^b3 , or> SiR ^b4 R ^b5 . R ^b1 to R ^b5 each independently represent a hydrogen atom or a substituent. * 1 and * 2 in the general formula (1) indicate that they are bonded to * 1 and * 2 in the general formulas (2-1) to (2-3), respectively. The method according to claim 1,
At least one of Ar ¹ and R ¹ , Ar ¹ and R ² , and at least one of R ¹ and R ² , and Ar ² and R ³ , Ar ² and R ^4, and at least one of R ³ and R ⁴ in Formula (1) Respectively, to form a ring. The method according to claim 1 or 2,
Wherein the group forming the ring in R ¹ , R ² , R ³ and R ⁴ in the general formula (1) is an aryl group which may have a substituent or a heteroaryl group which may have a substituent. The method according to claim 1 or 2,
In the general formula (1), Ar ¹ and R ¹ , and Ar ² and R ³ are bonded to each other to form a ring. The method according to claim 1 or 2,
A ¹ is a group represented by the general formula (2-1). The method according to claim 1 or 2,
In the general formula (1), X ¹ and X ² are both oxygen atoms. The method according to claim 1 or 2,
Wherein a dipole moment of the compound represented by the general formula (1) is 1D or less. The method according to claim 1 or 2,
Wherein the compound represented by the general formula (1) has a molecular weight of 500 or more and less than 850. The method according to claim 1 or 2,
Wherein the photoelectric conversion film further comprises an organic n-type compound. The method according to claim 1 or 2,
Wherein a charge blocking film is disposed between the electroconductive film and the transparent electroconductive film. A light sensor comprising the photoelectric conversion element according to claim 1 or 2. An image pickup device comprising a photoelectric conversion element according to claim 1 or 2.

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