Image sensor and image processing apparatus including the same, and electronic device

Abstract

To provide an image sensor including an organic photoelectric conversion element with a two-layer laminate structure.SOLUTION: An image sensor includes: a first organic photoelectric conversion element 100 that is disposed below a light incidence surface, selectively absorbs light in a first wavelength region within a visible light wavelength region, and converts the light into an electric signal; and a second organic photoelectric conversion element 200 that selectively absorbs light in the visible light wavelength region and converts the light into an electric signal. The image sensor includes a first section (i) and a second section (ii). The first section (i) includes a first optical filter 300 that selectively transmits light in a second wavelength region different from the first wavelength region. The second section (ii) includes a second optical filter 400 that selectively transmits light in a third wavelength region different from the first and second wavelength regions.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an image sensor, and more particularly to an image sensor having a structure in which two layers are stacked: an organic photoelectric conversion element that selectively absorbs light in a certain wavelength range of visible light and converts it into an electrical signal, and an organic photoelectric conversion element that non-selectively absorbs light in the visible light range and converts it into an electrical signal; an image processing apparatus and an electronic device including the same. [Background technology]

[0002] CMOS image sensors, which utilize silicon photodiodes, require smaller pixels as the resolution increases. However, a problem arises when the pixel size decreases: the light absorption area of ​​the silicon photodiode decreases, which leads to a decrease in the sensitivity of the image sensor.

[0003] Organic photoelectric materials not only have a high absorption coefficient, but their molecular structure also allows them to selectively absorb light in specific wavelength ranges. Therefore, if organic photoelectric conversion materials are applied to image sensors, the sensitivity and integration density of the image sensors can be improved. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2003-198958 [Overview of the project] [Problems that the invention aims to solve]

[0005] The present invention has been made in view of the problems of the above-mentioned conventional image sensors, and the object of the present invention is to provide an image sensor having a structure in which an organic photoelectric conversion element selectively absorbs light in a certain wavelength range of visible light and converts it into an electrical signal, and an organic photoelectric conversion element non-selectively absorbs light in the visible light range and converts it into an electrical signal, stacked in two layers, as well as an image processing apparatus and an electronic device including the same. Another object of the present invention is to provide an image sensor having a structure in which an organic photoelectric conversion element that selectively absorbs light in the blue wavelength region and converts it into an electrical signal, or an organic photoelectric conversion element that selectively absorbs light in the red wavelength region and converts it into an electrical signal, and an organic photoelectric conversion element that selectively absorbs light in the green wavelength region and converts it into an electrical signal are stacked in two layers, as well as an image processing apparatus and an electronic device including the same. [Means for solving the problem]

[0006] To achieve the above objective, the present invention provides an image sensor comprising: a first organic photoelectric conversion element disposed below the light incident surface, which selectively absorbs light in a first wavelength region belonging to the visible light wavelength region and converts it into an electrical signal; and a second organic photoelectric conversion element disposed below the first organic photoelectric conversion element, which non-selectively absorbs light in the visible light wavelength region and converts it into an electrical signal, wherein the first organic photoelectric conversion element and the second organic photoelectric conversion element are disposed on a substrate, the substrate does not contain a silicon-based photodiode, and the first organic photoelectric conversion element and the second organic photoelectric conversion element each independently have an upper electrode, a lower electrode, and the upper electrode and the lower electrode The image sensor includes an organic photoelectric conversion layer disposed between the first and second sections, the first section includes the first organic photoelectric conversion element, the second organic photoelectric conversion element, and a first optical filter disposed between the first and second organic photoelectric conversion elements, which belongs to the visible light wavelength region and selectively transmits light in a second wavelength region different from the first wavelength region, the second section includes the first organic photoelectric conversion element, the second organic photoelectric conversion element, and a second optical filter disposed between the first and second organic photoelectric conversion elements, which belongs to the visible light wavelength region and selectively transmits light in a third wavelength region different from the first and second wavelength regions. Furthermore, each of the organic photoelectric conversion layers of the first organic photoelectric conversion element and the second organic photoelectric conversion element comprises at least one p-type semiconductor material and at least one n-type semiconductor material, each of the organic photoelectric conversion layers of the first organic photoelectric conversion element and the second organic photoelectric conversion element independently comprises one of the compounds represented by chemical formulas 2 to 7 shown below as the p-type semiconductor material, and each of the organic photoelectric conversion layers of the first organic photoelectric conversion element and the second organic photoelectric conversion element independently comprises fullerene as the n-type semiconductor material. An image sensor characterized by the following features. [ka] [ka] [ka] [ka] [ka] [ka]

[0007] An image processing apparatus according to the present invention, made to achieve the above objective, is characterized by including the above-mentioned image sensor of the present invention.

[0008] An electronic device according to the present invention, made to achieve the above objective, is characterized by including the above-mentioned image sensor of the present invention.

[0009] Furthermore, the image sensor according to the present invention, which was made to achieve the above objective, includes a blue organic photoelectric conversion element that includes a blue organic photoelectric conversion layer at the bottom of the light incident surface that selectively absorbs light in the blue wavelength region and converts it into an electrical signal, At the bottom of the aforementioned blue organic photoelectric conversion element A first section includes a green organic photoelectric conversion element, which contains a green organic photoelectric conversion layer that selectively absorbs light in the green wavelength region and converts it into an electrical signal, and these elements are sequentially stacked and arranged. A red organic photoelectric conversion element includes a red organic photoelectric conversion layer at the bottom of the light incident surface that selectively absorbs light in the red wavelength region and converts it into an electrical signal, Below the aforementioned red organic photoelectric element An image sensor having a second section containing a green organic photoelectric conversion element that selectively absorbs light in the green wavelength region and converts it into an electrical signal, wherein the image sensor does not include a color filter, and the ratio of the maximum peak external quantum efficiency in the blue wavelength region to the maximum peak external quantum efficiency in the green wavelength region, the ratio of the maximum peak external quantum efficiency in the red wavelength region to the maximum peak external quantum efficiency in the green wavelength region, or all of these is 0.5 or greater. The blue organic photoelectric element, the red organic photoelectric element, and the green organic photoelectric element are each arranged on a substrate, and the first section and the second section are arranged adjacent to each other along the in-plane direction of the substrate. It is characterized by the following:

[0010] An image processing apparatus according to the present invention, made to achieve the above objective, is characterized by including the above-mentioned image sensor of the present invention.

[0011] An electronic device according to the present invention, made to achieve the above objective, is characterized by including the above-mentioned image sensor of the present invention. [Effects of the Invention]

[0012] The present invention provides an image sensor, an image processing apparatus including the same, and an electronic device, which provide an image sensor having a structure in which a plurality of organic photoelectric conversion elements are stacked. This provides an image sensor with improved integration density and sensitivity, and / or an image sensor with excellent color absorption balance, and such an image sensor can be applied to a variety of electronic devices. [Brief explanation of the drawing]

[0013] [Figure 1] This is a schematic block diagram illustrating an image processing device according to one embodiment of the present invention. [Figure 2] This is a schematic perspective view illustrating an image sensor according to one embodiment of the present invention. [Figure 3] This is a schematic cross-sectional view of an image sensor according to one embodiment of the present invention. [Figure 4A] This is a schematic cross-sectional view showing an image sensor according to another embodiment of the present invention. [Figure 4B] This is a schematic cross-sectional view showing an image sensor according to another embodiment of the present invention. [Figure 5] This is a schematic perspective view illustrating an image sensor according to another embodiment of the present invention. [Figure 6] This is a schematic block diagram illustrating an electronic device according to one embodiment of the present invention. [Figure 7] This graph shows the photoelectric characteristics of an organic photoelectric conversion element according to an embodiment of the present invention. [Figure 8] This graph shows the photoelectric characteristics of an organic photoelectric conversion element according to an embodiment of the present invention. [Figure 9] This graph shows the photoelectric characteristics of an organic photoelectric conversion element according to an embodiment of the present invention. [Figure 10] This graph shows the photoelectric characteristics of an organic photoelectric conversion element according to an embodiment of the present invention. [Figure 11] This graph shows the photoelectric characteristics of an organic photoelectric conversion element according to an embodiment of the present invention. [Modes for carrying out the invention]

[0014] Next, specific examples of embodiments for implementing the image sensor, image processing apparatus, and electronic device according to the present invention will be described with reference to the drawings.

[0015] The terms used herein are for illustrative purposes only to describe specific embodiments and are not intended to limit the technical ideas. The terms "top" or "upper" can include not only those directly above / below / to the left / right upon contact, but also those above / below / to the left / right without direct contact. A singular expression can include multiple expressions unless the context clearly indicates otherwise. Terms such as "includes" or "possesses," unless otherwise stated, indicate the presence of features, figures, stages, operations, components, parts, ingredients, materials, or combinations thereof described in the specification, and should not be understood to presuppose the presence or possibility of adding one or more other features, figures, stages, operations, components, parts, ingredients, materials, or combinations thereof. Terms such as "first," "second," and "third" are used to describe various components, but they are used solely to distinguish one component from others, and do not limit the order or type of the components. Furthermore, terms such as "unit," "means," "module," and "...part" refer to a comprehensive configuration unit that processes any function or operation, which can be embodied in hardware or software, or in a combination of hardware and software.

[0016] Unless otherwise defined, the term "substitution" means that a hydrogen atom in a compound is substituted with a substituent selected from halogen atoms, hydroxyl groups, alkoxy groups, nitro groups, cyano groups, amino groups, azide groups, amidino groups, hydrazino groups, hydrazono groups, carbonyl groups, carbamoyl groups, thiol groups, ester groups, carboxyl groups and their salts, sulfonic acid groups and their salts, phosphoric acid and its salts, silyl groups, C1-C20 alkyl groups, C2-C20 alkenyl groups, C2-C20 alkynyl groups, C6-C30 aryl groups, C7-C30 arylalkyl groups, C1-C30 alkoxy groups, C1-C20 heteroalkyl groups, C3-C20 heteroaryl groups, C3-C20 heteroarylalkyl groups, C3-C30 cycloalkyl groups, C3-C15 cycloalkenyl groups, C6-C15 cycloalkynyl groups, C3-C30 heterocycloalkyl groups, and combinations thereof.

[0017] Unless otherwise defined, the term "hetero" refers to a material containing 1 to 4 heteroatoms selected from N, O, S, Se, Te, Si, and P. The term "combination" includes forms in which two or more elements are mixed or layered, unless otherwise defined.

[0018] Embodiments of the present invention will be described below with reference to the drawings. In drawings, the same reference numerals refer to the same component, and the size of each component (such as the width and thickness of layers or areas) may be exaggerated in the drawings for clarity and convenience of explanation. On the other hand, the embodiments described below are merely illustrative, and various modifications are possible from these embodiments.

[0019] According to one embodiment of the present invention, an image sensor and an imaging device comprising an organic photoelectric conversion element are provided. Figure 1 is a schematic block diagram illustrating the image processing device. Specifically, the image processing device 1 includes an image sensor 10 and an image processor 40. The image sensor 10 operates according to control commands from the image processor 40, converting light reflected or transmitted by the object 30 into an electrical signal and outputting it to the image processor 40.

[0020] The image sensor 10 includes a pixel array 11, a low driver 12, a column driver 13, a timing controller 14, and a readout circuit 15, among others. The pixel array 11 includes multiple pixels PX. Pixel PX includes an organic photoelectric element (e.g., an organic photodiode) that accepts light and generates an electric charge. The row driver 12 can drive the pixel array 11 row by row. For example, the low driver 12 generates transmission control signals to control the transmission transistors of each pixel PX, reset control signals to control the reset transistors, and selection control signals to control the selection transistors.

[0021] The column driver 13 may include a Correlated Double Sampler (CDS), an Analog-to-Digital Converter (ADC), and the like. The correlated double sampler receives signals from pixels PX included in rows selected by row selection signals supplied by the low driver 12 and performs correlated double sampling. The analog-to-digital converter converts the output of the correlated duplex sampler into a digital signal and transmits it to the readout circuit 15. The readout circuit 15 may include a latch or buffer circuit and an amplifier circuit that can temporarily store the digital signal. The readout circuit 15 can temporarily store the digital signal received from the column driver 13, or amplify it to generate image data.

[0022] The operating timing of the low driver 12, the column driver 13, and the readout circuit 15 can be determined by the timing controller 14. The timing controller 14 operates according to control commands transmitted by the image processor 40. The image processor 40 processes the image data transmitted by the readout circuit 15 and outputs it to a display device or other device, or stores it in a storage device such as memory.

[0023] According to one embodiment of the present invention, the image sensor may have a structure in which two layers of organic photoelectric conversion elements are stacked. Organic photoelectric conversion elements can improve the sensitivity and integration density of image sensors. Compared to silicon photodiodes, they can be implemented with a thinner profile and smaller area, allowing for more circuit design space and enabling diverse functional designs. The image sensor could be a CMOS image sensor.

[0024] Figure 2 is a schematic perspective view illustrating the pixel array of an image sensor according to one embodiment of the present invention. Referring to Figure 2, the pixel array of the image sensor 10 includes, for example, unit pixel groups arranged iteratively along rows and / or columns, and each unit pixel group includes multiple pixels PX.

[0025] For example, a plurality of pixels PX are arranged below the light incident surface and include a first pixel 10a that selectively detects light in a first wavelength region, a second pixel 10b that selectively detects light in a second wavelength region, and a third pixel 10c that selectively detects light in a third wavelength region, with the second pixel 10b and the third pixel 10c arranged on the same plane below the first pixel 10a. The first wavelength region, the second wavelength region, and the third wavelength region are mutually distinct wavelength regions belonging to the visible light wavelength region, and constitute the three primary colors: green, blue, and red. For example, the first wavelength region is the green wavelength region (e.g., the wavelength region from 500 nm to 600 nm), the second wavelength region is the blue wavelength region (e.g., the wavelength region from 380 nm to less than 500 nm), and the third wavelength region is the red wavelength region (e.g., the wavelength region from over 600 nm to 700 nm).

[0026] The image sensor 10 has a two-layer structure in which a first organic photoelectric conversion element selectively absorbs light in a certain wavelength range of visible light and converts it into an electrical signal, and a second organic photoelectric conversion element non-selectively absorbs light in the visible light range and converts it into an electrical signal.

[0027] Figure 3 is a schematic cross-sectional view showing an image sensor according to one embodiment of the present invention. Referring to Figure 3, the image sensor 10 has a first organic photoelectric conversion element 100 and a second organic photoelectric conversion element 200 arranged sequentially below the light incident surface, and a first optical filter 300 that selectively transmits light in the second wavelength region and a second optical filter 400 that selectively transmits light in the third wavelength region may be additionally arranged on the same plane between the first organic photoelectric conversion element 100 and the second organic photoelectric conversion element 200. In other words, the image sensor 10 includes a first section (i) containing a first organic photoelectric conversion element 100, a first optical filter 300, and a second organic photoelectric conversion element 200, and a second section (ii) containing a first organic photoelectric conversion element 100, a second optical filter 400, and a second organic photoelectric conversion element 200. The first section (i) and the second section (ii) are arranged adjacent to each other along the plane.

[0028] Referring to Figures 2 and 3, the first organic photoelectric conversion element 100 constitutes the first pixel 10a, the combination of the first optical filter 300 and the second organic photoelectric conversion element 200 constitutes the second pixel 10b, and the combination of the second optical filter 400 and the second organic photoelectric conversion element 200 constitutes the third pixel 10c. The first and second organic photoelectric conversion elements (100, 200) include upper electrodes (110, 210) and lower electrodes (130, 230), and between the upper electrodes (110, 210) and lower electrodes (130, 230) are a first organic photoelectric conversion layer 120 and a second organic photoelectric conversion layer 220, respectively.

[0029] One of the upper electrodes (110, 210) and the lower electrodes (130, 230) is the anode, and the other is the cathode. For example, the lower electrode (130, 230) may be the anode and the upper electrode (110, 210) may be the cathode, or the lower electrode (130, 230) may be the cathode and the upper electrode (110, 210) may be the anode.

[0030] The upper electrodes (110, 210) and / or lower electrodes (130, 230) may be transparent electrodes. Transparent electrodes can have a high transmittance of approximately 80% or more and may include oxide conductors, carbon conductors, and / or metal thin films. For example, oxide conductors include indium tin oxide (ITO), indium zinc oxide (IZO), zinc tin oxide (ZTO), aluminum tin oxide (AlTO), aluminum zinc oxide (AZO), zinc oxide (ZnO), tin oxide (SnO), and / or fluorine-doped tin oxide (FTO); carbon conductors include graphene and / or carbon nanobodies; and metal thin films may include aluminum (Al), magnesium (Mg), silver (Ag), gold (Au), alloys thereof, or combinations thereof.

[0031] The upper electrodes (110, 210) or lower electrodes (130, 230) may be light-receiving electrodes located on the light incident surface side. Figure 3 shows an example where the upper electrodes (110, 210) are photodetectors. One of the upper electrodes (110, 210) or the lower electrodes (130, 230) is a common electrode, and the other is a pixel electrode. A predetermined voltage is applied to the upper electrodes (110, 210) or lower electrodes (130, 230) through wiring (not shown), and as a result, an electric field is formed between the two electrodes. Furthermore, the upper electrodes (110, 210) and / or lower electrodes (130, 230) may be electrodes for collecting the charge generated in the organic photoelectric conversion layer (120, 220).

[0032] The first organic photoelectric conversion layer 120 selectively absorbs light in the first wavelength region and converts it into an electrical signal. Specifically, the first organic photoelectric conversion layer 120 has a maximum absorption wavelength (λ) within the first wavelength region. a、max ) has such that the absorption spectrum in the first wavelength region is higher than the absorption spectrum in other wavelength regions. For example, the absorbance spectral area within the first wavelength region may be 70% or more, 75% or more, 80% or more, 85% or more, 90% or more, or 95% or more of the total absorbance spectral area.

[0033] The second organic photoelectric conversion layer 220 non-selectively absorbs light in a wavelength range including the visible light region and converts it into an electrical signal. Specifically, the second organic photoelectric conversion layer 220 has the property of absorbing light in the entire visible light range, in other words, it exhibits absorption characteristics across the entire wavelength range from 380 nm to 700 nm. For example, the second organic photoelectric conversion layer 220 may exhibit higher absorption spectra in the wavelength range of 380 nm to 700 nm than in the absorption spectra in the wavelength range of less than 380 nm and / or in the wavelength range of more than 700 nm. Specifically, the absorbance spectral area in the visible light region (for example, the wavelength region between 380 nm and 700 nm) may be 70% or more, 75% or more, 80% or more, 85% or more, 90% or more, or 95% or more of the total absorbance spectral area.

[0034] The second organic photoelectric conversion layer 220 may contain an absorbent material that absorbs light in the entire visible light spectrum, or it may contain absorbent materials that absorb light in different wavelength ranges from each other. For example, the second organic photoelectric conversion layer 220 may be in a form in which a light-absorbing material that absorbs light in the blue wavelength region, a light-absorbing material that absorbs light in the green wavelength region, and a light-absorbing material that absorbs light in the red wavelength region are mixed.

[0035] The first and second organic photoelectric conversion layers (120, 220) receive incident light to generate excitons, and then separate the generated excitons into holes and electrons. The organic photoelectric conversion layer (120, 220) may contain a p-type semiconductor material and an n-type semiconductor material. p-type semiconductor materials and / or n-type semiconductor materials are light-absorbing materials and have the maximum peak absorption wavelength (λ) in the same or different wavelength regions. max ) has. At least one of the p-type and n-type semiconductor materials can be an organic material. For example, p-type semiconductor materials can be organic materials. For example, p-type and n-type semiconductor materials can both be organic materials.

[0036] The HOMO energy level of a p-type semiconductor material is 4.0 eV or higher, 4.1 eV or higher, or 4.2 eV or higher, and may be 6.0 eV or lower, 5.9 eV or lower, or 5.8 eV or lower. Furthermore, the LUMO energy levels of p-type semiconductor materials are 1.8 eV or higher, 1.9 eV or higher, or 2.0 eV or higher, and may be 4.0 eV or lower, 3.9 eV or lower, or 3.8 eV or lower. The energy band gap of p-type semiconductor materials is 2.4 eV or less, 2.3 eV or less, or 2.2 eV or less, and can be 1.8 eV or more, 1.9 eV or more, or 2.0 eV or more.

[0037] The first and second organic photoelectric conversion layers (120, 220) are each independently made of a p-type semiconductor material, with a maximum absorption wavelength (λ) in the green wavelength region. a、max It contains compounds having ). Specifically, p-type semiconductor materials have a maximum absorption wavelength (λ). a、max) may be present within a wavelength range of 500 nm or more, 520 nm or more, 600 nm or less, or 580 nm or less. This compound exhibits a higher absorption spectrum in the wavelength range of 500 nm or more, 520 nm or more, 600 nm or less, or 580 nm or less than in other wavelength ranges. For example, the absorption spectrum area in the wavelength range of 500 nm or more, 520 nm or more, 600 nm or less, or 580 nm or less may be 70% or more, 75% or more, 80% or more, 85% or more, 90% or more, or 95% or more of the total absorption spectrum area.

[0038] The p-type semiconductor materials of the first and second organic optoelectronic conversion layers (120, 220) may each independently contain a compound represented by Chemical Formula A shown below. (Chemical Formula A) EDM1-LM1-EAM1 ··· Chemical Formula A In Chemical Formula A, EDM1 is an electron-donating moiety, EAM1 is an electron-accepting moiety, LM1 is a π-conjugated linking moiety that links an electron-donating moiety and an electron-accepting moiety.

[0039] The p-type semiconductor material may be a compound represented by Chemical Formula A-1 shown below.

Chemical Formula

[0040] For example, Ar 1a and Ar 2a Each of these independently comprises a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted anthracenyl group, a substituted or unsubstituted phenantrenyl group, a substituted or unsubstituted pyridinyl group, a substituted or unsubstituted pyridazinyl group, a substituted or unsubstituted pyrimidinyl group, a substituted or unsubstituted pyrazinyl group, a substituted or unsubstituted quinolinyl group, a substituted or unsubstituted isoquinolinyl group, and a substituted or unsubstituted naphthyl group. It may be a naphyridinyl group, a substituted or unsubstituted cinnolinyl group, a substituted or unsubstituted quinazolinyl group, a substituted or unsubstituted phthalazinyl group, a substituted or unsubstituted benzotriazinyl group, a substituted or unsubstituted pyridopyrazinyl group, a substituted or unsubstituted pyridopyrimidinyl group, or a substituted or unsubstituted pyridopyridazinyl group.

[0041] Ar 1a and Ar 2a They fuse together to form a ring. For example, Ar1a and Ar 2a This is a single bond, -(CR c R d ) n1 -(n1 is an integer of 1 or 2), -O-, -S-, -Se-, -N=, -NR e -, -SiR f R g -, or -GeR h R i They can be connected through - to form a ring. Here R c ~R i Each of these can independently be hydrogen, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C3-C30 heteroaryl group, a substituted or unsubstituted C1-C6 alkoxy group, a halogen, a cyano group, or a combination thereof.

[0042] Specifically, a p-type semiconductor material may contain one or more compounds represented by any one of the chemical formulas A-2 to A-9 shown below. [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] In chemical formulas A-2 to A-9, X is O, S, Se, Te, SO, SO2, or SiR a R b And, Ar 3 This is a substituted or unsubstituted C6-C30 arylene group, a substituted or unsubstituted C3-C30 heterocyclic group, or two or more fusion rings selected from these. R 1a ~R 5a , R a , and R b Each of these is independently hydrogen, deuterium, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C1-C30 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C3-C30 heteroaryl group, a halogen, a cyano group, or a combination thereof. G 1 and / or G 2 These are independent, single bonds, -(CR c R d ) n1 -(n1 is an integer of 1 or 2), -O-, -S-, -Se-, -N=, -NR e -, -SiR f R g -, or -GeR h R i -and (R c ~R i Each of these is independently hydrogen, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C3-C30 heteroaryl group, a substituted or unsubstituted C1-C6 alkoxy group, a halogen, a cyano group, or a combination thereof, R c and R d , R f and R g , and R h and R i (Each element may exist independently or be connected to each other to form a ring.) Y is O, S, Se, Te, or C(R j )(CN)(R here j (is selected from hydrogen, a cyano group (-CN), or a C1-C10 alkyl group), R6a ~R 6e and R 7a ~R 7e Each of these is independently hydrogen, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C1-C30 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C3-C30 heteroaryl group, a halogen, a cyano group, or a combination thereof. R 1a ~R 3a , R 6a ~R 6e , and R 7a ~R 7e These elements either exist independently or two adjacent elements are linked together to form a fused ring.

[0043] As an example, Ar of chemical formulas A-3, A-5, A-7, and / or A-9 3 This can be benzene, naphthylene, anthracene, thiophene, selenofene, telolofene, pyridine, pyrimidine, or two or more fusion rings selected from these.

[0044] n-type semiconductor materials may have a LUMO energy level of 3.3eV or higher, 3.4eV or higher, 3.5eV or higher, 4.7eV or lower, 4.6eV or lower, or 4.5eV or lower, and a HOMO energy level of 5.3eV or higher, 5.4eV or higher, 5.5eV or higher, 6.7eV or lower, 6.6eV or lower, or 6.5eV or lower. The n-type semiconductor material of the first and second organic photoelectric conversion layers (120, 220) has excellent charge mobility. For example, the n-type semiconductor material in the first and second organic photoelectric conversion layers (120, 220) is independently 1.0 × 10⁻⁶ -10 cm 2 / V·s or more, 1.0×10 -9 cm 2 / V·s or more, 1.0×10 -8 cm 2 / V·s or more, 1.0×10 -7 cm 2 / V·s or more, 1.0×10 -3 cm 2 / V·s or less, 1.0×10 -2 cm 2 / V·s or less, 1.0×10 -1 cm 2 / V·s or less, or 1.0cm 2 It may have a charge mobility of less than / V·s.

[0045] The n-type semiconductor material of the first and second organic photoelectric conversion layers (120, 220) is independently a metal-organic complex or derivative thereof such as Tris(8-hydroxyquinolinato)aluminum(Alq3), Subphthalocyanine(SubPc), or Phthalocyanine(Pc); a carboxylic acid anhydride or derivative thereof such as naphthalenetetracarboxylic dianhydride (1,4,5,8-Naphthalenetetracarboxylic dianhydride:NTCDA); a perylenediimide or derivative thereof such as dimethylphenylperylenetetracarboxylic diimide (N,N'-Bis(2,6-dimethylphenyl)perylene-3,4,9,10-tetracarboxylic diimide); thiophene or a thiophene derivative; C 60 , C 70 , C 78 , C 80 These may be fullerenes or fullerene derivatives.

[0046] The first and second organic photoelectric conversion layers (120, 220) may be a single layer or multiple layers. Specifically, the first and second organic photoelectric conversion layers (120, 220) can each be independently composed of various combinations, such as an intrinsic layer (I layer), a p-type layer / I layer, an I layer / n-type layer, a p-type layer / I layer / n-type layer, or a p-type layer / n-type layer.

[0047] The first organic photoelectric conversion layer 120 and the second organic photoelectric conversion layer 220 may contain p-type and n-type semiconductor materials of appropriate types and / or content (volume or thickness) depending on the desired absorption wavelength region. Specifically, the first organic photoelectric conversion layer 120 and the second organic photoelectric conversion layer 220 both contain a p-type semiconductor material capable of absorbing light in the green wavelength region, but also contain other types and / or amounts (volume or thickness) of n-type semiconductor material, allowing them to absorb light in different absorption wavelength regions (for example, the green and visible light absorption wavelength regions, respectively). For example, the second organic photoelectric conversion layer 220 can contain even more n-type semiconductor material than the first organic photoelectric conversion layer 120.

[0048] n-type semiconductor material of the second organic photoelectric conversion layer 220 (e.g., fullerene (C) 60 The content of the n-type semiconductor material (e.g., fullerene (C)) of the first organic photoelectric conversion layer 120 is 60 The amount may be 1.0 times or more, 2.0 times or more, 3.0 times or more, 3.5 times or more, 4.0 times or more, 100.0 times or less, 70.0 times or less, 50.0 times or less, 30.0 times or less, 20.0 times or less, 17.0 times or less, 15.0 times or less, or 12.0 times or less relative to the content. The first organic photoelectric conversion layer 120 has a volume ratio (thickness ratio when implemented in multiple layers) of n-type semiconductor material to p-type semiconductor material of 0.2 or more, and may be 2.0 or less. For example, the volume ratio of n-type semiconductor material to p-type semiconductor material may be 0.3 or higher, 0.5 or higher, 0.7 or higher, 0.9 or higher, 1.0 or higher, 1.2 or higher, 2.0 or lower, 1.8 or lower, or 1.6 or lower. The second organic photoelectric conversion layer 220 has a volume ratio (thickness ratio when implemented in multiple layers) of n-type semiconductor material to p-type semiconductor material of 2.0 or more, and may be 20.0 or less. For example, the volume ratio (thickness ratio) of n-type semiconductor material to p-type semiconductor material may be 2.5 or more, 3.0 or more, 3.5 or more, 4.5 or more, 15.0 or less, or 10.0 or less.

[0049] The first and second organic photoelectric conversion layers (120, 220) may each independently have a thickness of 10 nm or more, 30 nm or more, 50 nm or more, 100 nm or more, 150 nm or more, 200 nm or more, 1000 nm or less, 800 nm or less, 500 nm or less, 300 nm or less, 250 nm or less, or 200 nm or less. The thickness of the second organic photoelectric conversion layer 220 may be greater than the thickness of the first organic photoelectric conversion layer 120. For example, the thickness of the second organic photoelectric conversion layer 220 may be 100 nm or more, 150 nm or more, 200 nm or more, 1000 nm or less, or 800 nm or less.

[0050] The first and second organic photoelectric conversion elements (100, 200) may each independently further include a buffer layer (not shown) between the upper electrode (110, 210) and the organic photoelectric conversion layer (120, 220), and / or between the lower electrode (130, 230) and the organic photoelectric conversion layer (120, 220). Each buffer layer may independently be a hole transfer layer, a hole injection layer, a hole extraction layer, an electron barrier layer, an electron transfer layer, an electron injection layer, an electron extraction layer, a hole barrier layer, or a combination thereof. For example, a buffer layer (not shown) can effectively transfer or extract holes and electrons separated from the organic photoelectric conversion layer (120, 220) to the lower electrode (130, 230) and the upper electrode (110, 210), respectively.

[0051] Furthermore, the buffer layer (not shown) can block the reverse injection or transfer of the separated charge from the upper electrodes (110, 210) and / or the lower electrodes (130, 230) to the organic photoelectric conversion layer (120, 220) by an applied external voltage. The buffer layer may contain inorganic or organic substances. The inorganic buffer layer may contain, for example, lanthanum group elements, calcium (Ca), potassium (K), aluminum (Al), or alloys thereof. The lanthanum group elements may include ytterbium (Yb).

[0052] The organic buffer layer may include, for example, a low-molecular-weight semiconductor, a polymer semiconductor, or a combination thereof, having a higher charge mobility than the organic photoelectric conversion layer (120, 220). The charge mobility of the organic buffer layer may be 50 times or more higher than the charge mobility of the organic photoelectric conversion layer (120, 220). Specifically, the charge mobility of the organic buffer layer is 1.0×10 -3 cm 2 / Vs or more, 1.5×10 -3 cm 2 / Vs or more, or 2.0×10 -3 cm 2 / Vs or more, and can be 10 cm 2 / Vs or less.

[0053] The organic buffer layer may contain a compound represented by chemical formula B-1 and / or B-2 shown below.

Chemical formula

Chemical formula

[0054] Specifically, the organic buffer layer may contain compounds represented by the chemical formulas B-3 and / or B-4 shown below. [ka] [ka] In chemical formula B-3 or B-4, M 1 M 2 , G 3 , G 4 , R 1b ~R 8b As mentioned above, R 9b ~R 16b Each of them is independent of R 1b This is the same as the definition of [the same thing].

[0055] For example, the organic buffer layer may contain compounds represented by the chemical formulas B-5 and / or B-6 shown below. [ka] [ka] In chemical formula B-5 or B-6, R 1b ~R 8b As mentioned above, R k1 ~R l2 Each of them is independent of R k This is the same as the definition of [the same thing].

[0056] Furthermore, different types of materials may be applied depending on the placement of the buffer layer. For example, the buffer layer in contact with the n-type layer of the organic photoelectric conversion layer (120, 220) may contain BCP (Bathocuproine) or LiF, and the buffer layer in contact with the p-type layer of the organic photoelectric conversion layer (120, 220) may contain PEDOT (poly(3,4-ethylenedioxythiophene)) or PSS (poly(styrene sulfonate)). The first and second organic photoelectric conversion elements (100, 200) may each independently have a thickness of 50 nm or more, 80 nm or more, 100 nm or more, 1500 nm or less, 1200 nm or less, 1000 nm or less, 800 nm or less, or 500 nm or less. The thickness of the second organic photoelectric element 200 may be greater than the thickness of the first organic photoelectric element 100.

[0057] The first optical filter 300 and the second optical filter 400 selectively transmit light including the second wavelength region and light including the third wavelength region, respectively. Here, selective transmission of light including the second wavelength region could mean selectively transmitting light in the second wavelength region, or selectively transmitting light in both the second and first wavelength regions. Here, selective transmission of light including the third wavelength region could mean selectively transmitting light in the third wavelength region, or selectively transmitting light in both the third wavelength region and the first wavelength region.

[0058] Specifically, the first optical filter 300 has a maximum transmission wavelength (λ t、max ) is present in the second wavelength region, and the absorption spectrum in the second wavelength region may be lower than the absorption spectrum in other wavelength regions. For example, the absorption spectral area in the second wavelength region may be 30% or less, 25% or less, 20% or less, 15% or less, 10% or less, or 5% or less of the total absorption spectral area. The second optical filter 400 has a maximum transmission wavelength (λ t、max ) is present in the third wavelength region, and the absorption spectrum in the third wavelength region may be lower than the absorption spectrum in other wavelength regions. For example, the absorbance spectral area in the third wavelength region may be 30% or less, 25% or less, 20% or less, 15% or less, 10% or less, or 5% or less of the total absorbance spectral area.

[0059] The maximum absorption wavelength of the first organic photoelectric conversion element 100, the maximum transmission wavelength of the first optical filter 300, and the maximum transmission wavelength of the second optical filter 400 may be different from each other. For example, the maximum absorption wavelength of the first organic photoelectric conversion element may be within the green wavelength region (wavelength region of 500 nm or more, or 520 nm or more, and 600 nm or less, or 580 nm or less), the maximum transmission wavelength of the first optical filter 300 may be within the blue wavelength region (wavelength region of 400 nm or more, or 420 nm or more, and 520 nm or less, 500 nm or less, or 480 nm or less), and the maximum transmission wavelength of the second optical filter 400 may be within the red wavelength region (wavelength region of 580 nm or more, or 600 nm or more, and 700 nm or less, or 680 nm or less). As another example, the maximum absorption wavelength of the first organic photoelectric conversion element 100, the maximum transmission wavelength of the first optical filter 300, and the maximum transmission wavelength of the second optical filter 400 can each independently be located within the magenta wavelength region, the cyan wavelength region, or the yellow wavelength region.

[0060] The first and second organic photoelectric conversion elements (100, 200) are arranged on the substrate 500. The substrate 500 may be an organic semiconductor material, an inorganic semiconductor material, a flexible substrate, glass, or a combination thereof. For example, the substrate 500 may contain semiconductor materials such as Si, Ge, SiGe, and III-V group materials. For example, the first section (i) and the second section (ii) are arranged side by side along the planar direction of the substrate 500, and the first section (i) and the second section (ii) are arranged repeatedly along rows and / or columns along the planar direction of the substrate 500 to form an array.

[0061] The lower electrode 130 of the first organic photoelectric conversion element 100 and the substrate 500 are electrically connected through the charge transfer path 610. The length of the charge transfer path 610 is 150 nm or more, and may be 1500 nm or less. For example, the length of the charge transfer path 610 may be 170 nm or more, 200 m or more, 220 m or more, 250 m or more, 1400 nm or less, 1300 nm or less, 1200 nm or less, 1100 nm or less, 1000 nm or less, 900 nm or less, or 800 nm or less. Furthermore, the maximum aspect ratio of the charge transfer path 610 is 1.0 or greater and may be 15.0 or less. For example, the maximum aspect ratio of the charge transfer path 610 may be 1.5 or greater, 2.0 or greater, 2.5 or greater, 3.0 or greater, 14.0 or less, 13.0 or less, 12.0 or less, 11.0 or less, 10.0 or less, 9.0 or less, or 8.0 or less. The average aspect ratio of the charge transfer path 610 is 2.0 or greater and may be 10.0 or less. For example, the average major axis ratio of the charge transfer path 610 may be 2.5 or greater, 3.0 or greater, 9.0 or less, or 8.0 or less. The maximum major-to-minimum ratio of a charge transfer path is the ratio of its maximum length to its minimum width, while the average major-to-minimum ratio is the ratio of its average length to its average width. The charge transfer path 610 may be formed as a single unit or as two or more (611, 612) electrically connected. An image sensor according to one embodiment may have a smaller charge transfer path length and major axis ratio compared to an image sensor including a silicon photodiode.

[0062] The substrate 500 includes a pixel circuit 510. The pixel circuit 510 may include a transmission transistor, a drive transistor, a selection transistor, and a reset transistor, among others. The pixel circuit 510 is electrically connected to the first organic photoelectric conversion element 100 via the charge transfer path 610, and can also directly contact the second organic photoelectric conversion element 200. The substrate 500 does not necessarily have to include a separate photodetector element such as a silicon-based photodiode. Since the space occupied by the silicon-based photodiode within the substrate 500 is unnecessary, the arrangement of components within the substrate 500 becomes flexible. For example, it becomes possible to add separate circuits for each pixel, enabling a wider variety of circuit designs.

[0063] Furthermore, metal wiring (not shown) and pads (not shown) are formed on the substrate 500. Metal wiring and pads may include metals with low resistivity to reduce signal delay, such as aluminum (Al), copper (Cu), silver (Ag), and alloys thereof.

[0064] The image sensor 10 may further include insulating layers (lower insulating layer 710, interlayer insulating layer 720, upper insulating layer 730) above the first organic photoelectric element 100, between the first organic photoelectric conversion element 100 and the optical filters (300, 400), and / or between the second organic photoelectric conversion element 200 and the optical filters (300, 400). The insulating layers (710, 720, 730) may contain inorganic insulating materials or low dielectric constant (low K) materials. For example, inorganic insulators are silicon oxide and / or silicon nitride, and low dielectric constant (lowK) materials may be SiC, SiCOH, SiCO, SiOF, or combinations thereof. The interlayer insulating layer 720 between the first organic photoelectric conversion element 100 and the optical filters (300, 400) may be in a form in which the lower electrode 130 of the first organic photoelectric conversion element 100 is embedded. Furthermore, the upper insulating layer 710 and / or the lower insulating layer 730 may be a thin-film encapsulation layer that blocks moisture and / or oxygen from the outside.

[0065] The image sensor 10 may further include a condensing lens 800. The focusing lens 800 can be positioned on top of the first organic photoelectric conversion element 100, and can control the direction of incident light to focus the light to a single point. The condensing lens 800 may be placed for each pixel, or it may be placed across multiple pixels. The focusing lens 800 may be cylindrical or hemispherical in shape.

[0066] A transparent layer 900 may be further included between the first organic photoelectric conversion element 100 and the focusing lens 800. The transparent layer 900 is a reflective layer positioned on the side to which light is incident, thereby lowering the reflectivity of the incident light and further improving the light absorption. It may contain a material having a refractive index of 1.6 to 2.5. The transparent layer 900 may contain metal oxides, metal sulfides, and / or organic substances. For example, the transparent layer 900 may contain metal oxides such as aluminum-containing oxides, molybdenum-containing oxides, tungsten-containing oxides, vanadium-containing oxides, rhenium-containing oxides, niobium-containing oxides, tantalum-containing oxides, titanium-containing oxides, nickel-containing oxides, copper-containing oxides, cobalt-containing oxides, manganese-containing oxides, chromium-containing oxides, tellurium-containing oxides, or combinations thereof; metal sulfides such as zinc sulfide; or organic substances such as amine derivatives. According to another embodiment, an image sensor can be provided that has a structure in which two layers of organic photoelectric conversion elements are stacked, and exhibits excellent absorption balance between colors even without an optical filter (color filter).

[0067] Figures 4A and 4B show schematic cross-sectional views of an image sensor according to another embodiment of the present invention. Referring to Figures 4A and 4B, the image sensor 20 includes a blue organic photoelectric converter 2200 that selectively absorbs light in the blue wavelength region and converts it into an electrical signal, and a red organic photoelectric converter 2300 that selectively absorbs light in the red wavelength region and converts it into an electrical signal, both arranged on the same plane below the light incident surface. Below the blue organic photoelectric converter 2200 and the red organic photoelectric converter 2300, there are green organic photoelectric converters 2100 that selectively absorb light in the green wavelength region and convert it into an electrical signal. In other words, the image sensor 20 includes a first section (i) in which a blue organic photoelectric element 2200 and a green organic photoelectric element 2100 are sequentially stacked and arranged below the light incident surface, and a second section (ii) in which a red organic photoelectric element 2300 and a green organic photoelectric element 2100 are sequentially arranged below the light incident surface. In Figure 4B, the blue organic photoelectric element 2200 and the red organic photoelectric element 2300 are isolated (insulated) by the insulating layer 990.

[0068] Figure 5 is a schematic perspective view illustrating an image sensor according to another embodiment of the present invention. Referring to Figures 4A, 4B and 5, the blue organic photoelectric element 2200, the red organic photoelectric element 2300, and the green organic photoelectric element 2100 constitute the blue pixel 20a, the red pixel 20b, and the green pixel 20c, respectively. Such an image sensor 20 exhibits excellent absorption balance between blue, red, and green colors. As mentioned earlier, the organic photoelectric conversion layer contains both p-type and n-type semiconductor materials. n-type semiconductor material in the organic photoelectric conversion layer (for example, C 60 The higher the content of ), the higher the absorption rate of light in the blue wavelength region of the organic photoelectric conversion layer.

[0069] The image sensor 20 has a blue organic photoelectric converter 2200 that selectively absorbs light in the blue wavelength region near the light incident surface. Therefore, the blue organic photoelectric converter 2200 can preferentially absorb light in the blue wavelength region, preventing light in the blue wavelength region from being absorbed and lost beforehand by the green organic photoelectric converter 2300. Furthermore, the green organic photoelectric conversion element 2100 can further enhance wavelength selectivity for the green wavelength region by reducing the absorption of light in the blue wavelength region by the n-type semiconductor material. In other words, the blue organic photoelectric element 2200 can sufficiently absorb light in the blue wavelength region, thereby increasing the external quantum efficiency in the blue wavelength region, while the green organic photoelectric element 2100 can reduce the amount of light absorbed in the blue wavelength region, thereby increasing its sensitivity to the green wavelength region.

[0070] Specifically, the image sensor 20 exhibits a high absorption balance in the green wavelength region, the blue wavelength region, and the red wavelength region. For example, the ratio of the maximum peak external quantum efficiency in the blue wavelength region to the maximum peak external quantum efficiency in the green wavelength region and / or the ratio of the maximum peak external quantum efficiency in the red wavelength region to the maximum peak external quantum efficiency in the green wavelength region may be 0.5 or greater, 0.55 or greater, 0.6 or greater, 0.65 or greater, 0.7 or greater, 0.75 or greater, 0.8 or greater, 1.2 or less, 1.1 or less, 1.0 or less, or 0.95 or less, respectively. The external quantum efficiency is the external quantum efficiency when a predetermined voltage (e.g., 3.0V or 10.0V) is applied to each organic photoelectric conversion element (2100, 2200, 2300).

[0071] The blue organic photoelectric element 2200, the green organic photoelectric element 2100, and the red organic photoelectric element 2300 each include an organic photoelectric conversion layer (2220, 2120, 2320) between the upper electrode and the lower electrode that selectively absorbs light in the blue, green, and red wavelength regions, respectively, and converts it into an electrical signal. The organic photoelectric conversion layer (2220, 2120, 2320) contains p-type and n-type semiconductor materials. The structure of the organic photoelectric conversion layer (p-type layer / n-type layer, etc.) and the energy levels of p-type and n-type semiconductor materials can be found by referring to the information mentioned earlier. Each of the organic photoelectric conversion layers (2220, 2120, 2320) independently has a volume ratio (thickness ratio when multiple layers are implemented) of n-type semiconductor material to p-type semiconductor material of 0.2 or more, and may be 2.0 or less. For example, the volume ratio of n-type semiconductor material to p-type semiconductor material may be 0.3 or higher, 0.5 or higher, 0.7 or higher, 0.9 or higher, 1.0 or higher, 1.2 or higher, 2.0 or lower, 1.8 or lower, or 1.6 or lower.

[0072] The p-type semiconductor material in the organic photoelectric conversion layer (2220, 2120, 2320) has a maximum absorption wavelength (λ) in the blue wavelength region, green wavelength region, and red wavelength region, respectively. a、max It may contain compounds having ). The p-type semiconductor material of the organic photoelectric conversion layer (2220, 2120, 2320) can exhibit an absorption spectrum in a desired absorption wavelength region that is higher than the absorption spectrum in other wavelength regions. For example, the absorption spectrum in the desired absorption wavelength region may account for 70% or more, 75% or more, 80% or more, 85% or more, 90% or more, or 95% or more of the total absorption spectrum area. The p-type semiconductor material in the organic photoelectric conversion layers (2220, 2120, 2320) can each independently contain the compound represented by the aforementioned chemical formula A.

[0073] The p-type semiconductor material of the blue organic photoelectric conversion layer 2220 may include substances known in the industry as organic compounds that selectively absorb light in the blue wavelength region and convert it into electrical signals. For example, p-type semiconductor materials may include thiophene, thiophene derivatives, rubrene, rubrene derivatives, tetracene, tetracene derivatives, coumarin, coumarin derivatives, and the like. Specifically, the p-type semiconductor material may be bi-phenyl-tri-thiophene.

[0074] The p-type semiconductor material of the green organic photoelectric conversion layer 2120 may include substances known in the art as organic compounds that selectively absorb light in the green wavelength region and convert it into an electrical signal. For example, a p-type semiconductor material may contain one or more compounds represented by any one of the chemical formulas A-1 to A-9 mentioned earlier. The p-type semiconductor material of the red organic photoelectric conversion layer 2320 may include substances known in the art as organic compounds that selectively absorb light in the red wavelength region and convert it into an electrical signal. For example, p-type semiconductor materials may include metal-phthalocyanine derivatives such as copper phthalocyanine, or derivatives thereof. The n-type semiconductor material of the organic photoelectric conversion layers (2220, 2120, 2320) can be based on the n-type semiconductor material of the first and second organic photoelectric conversion layers (120, 220), and one or more of the organic photoelectric conversion layers (2220, 2120, 2320) (for example, all three layers) may be fullerene (C) as the n-type semiconductor material. 60 ) can include

[0075] The organic photoelectric elements (2200, 2100, 2300) are placed on the substrate 500, and the lower electrodes (2230, 2330) of the blue and red organic photoelectric elements (2200, 2300) and the substrate 500 are electrically connected through the first and second charge transfer paths (621, 622), respectively. Since the image sensor 20 does not include an optical filter between the two stacked organic photoelectric conversion elements, the length and / or ratio of the major axis of the first and second charge transfer paths (621, 622) is reduced. The lengths of the first and second charge transfer paths (621, 622) are independently 50 nm or more, and may be 500 nm or less. For example, the lengths of the first and second charge transfer paths (621, 622) are independently 70 nm or more, 100 nm or more, 120 nm or more, or 150 nm or more, and may be 450 nm or less, 400 nm or less, 350 nm or less, or 300 nm or less.

[0076] The maximum aspect ratio of the first and second charge transfer paths (621, 622) is independently 0.5 or greater and may be 10.0 or less. For example, the maximum aspect ratio of the first and second charge transfer paths (621, 622) can independently be 1.0 or greater, 1.5 or greater, 2.0 or greater, 9.0 or less, 8.0 or less, 7.0 or less, 6.0 or less, or 5.0 or less. The average aspect ratio of the first and second charge transfer paths (621, 622) is independently 2.0 or greater and may be 7.0 or less. For example, the average major axis ratio of the first and second charge transfer paths (621, 622) can be 2.5 or greater, 3.0 or greater, 6.5 or less, or 6.0 or less, independently of each other.

[0077] An optical filter (not shown) that selectively absorbs light in the blue wavelength region may be further placed between the light incident surface of the image sensor 20 and the red organic photoelectric conversion element 2300. Such optical filters can absorb light in the blue wavelength region first at the light incident surface, thereby improving the selective wavelength absorption rate of red and green organic photoelectric conversion elements (2100, 2300). This optical filter may contain the same light-absorbing material as the blue organic photoelectric conversion layer 2220 and may be formed simultaneously with the blue organic photoelectric conversion layer 2220. Similarly, an optical filter (not shown) that selectively absorbs light in the red wavelength region can be further placed between the light incident surface of the image sensor 20 and the blue organic photoelectric conversion element 2200.

[0078] The image sensors (10, 20) can be manufactured using methods commonly known in the industry. Specifically, the image sensors (10, 20) may be manufactured by including the steps of forming lower organic photoelectric elements (200, 2100) on a substrate 500, forming a lower insulating layer 710, forming a charge transfer path, forming upper organic photoelectric elements (100, 2200, 2300), forming an upper insulating layer 730, and forming a transparent layer 900 and a focusing lens 800. The image sensor 10 may be manufactured by further including the steps of forming the first and second optical filters (300, 400) after forming the lower insulating layer 710, and then forming the interlayer insulating layer 720. Organic photoelectric conversion elements (200, 2100, 2200, 2300) can be manufactured by patterning a conductive film to form a lower electrode (pixel electrode), then forming an organic photoelectric conversion layer, and finally forming a conductive film on top of it as an upper electrode (common electrode). Methods commonly known in the industry are used for patterning electrodes, organic photoelectric conversion layers, charge transfer paths, insulating layers, transparent layers, focusing lenses, etc. For example, deposition processes such as shadow masks, hard masks using SiN, and photolithography processes may be used.

[0079] The image sensors (10, 20) and / or the image device 1 can be applied to a variety of electronic devices. Specifically, the electronic device may be a mobile phone, a camera, a biometric authentication device, or an automotive electrical component. The electronic device may include, for example, a fingerprint recognition sensor embedded in a display.

[0080] Figure 6 is a schematic block diagram illustrating an electronic device according to one embodiment of the present invention. Referring to Figure 6, the electronic device 2 includes image sensors (10, 20), an input / output device 21, a memory 22, a processor 23, and a port 24. Although not shown in the diagram, electronic device 2 may further include wireless communication equipment, power supply equipment, and the like. Port 24 is a device provided for electronic device 2 to communicate with a video card, sound card, memory card, USB device, etc.

[0081] Processor 23 performs specific operations, instructions, and / or tasks. The processor 23 is a central processing unit (CPU) or microprocessor unit (MCU) and can communicate with the memory 22, input / output devices 21, image sensors (10, 20) and / or other devices connected to port 24 via the bus 25. Memory 22 is a storage medium for storing data necessary for the operation of the electronic device 2, or multimedia data, etc. Memory 22 may include volatile memory such as random access memory (RAM) or non-volatile memory such as flash memory. The memory 22 may also include a solid-state drive (SSD), a hard disk drive (HDD), and / or an optical drive (ODD) as storage devices. The input / output device 21 includes input devices such as a keyboard, mouse, and touchscreen provided to the user, and output devices such as a display and an audio output unit. The image sensors (10, 20) are connected to the processor 23 by bus 25 or other means of communication. The processor 23 can perform the functions of the image processor 40 shown in Figure 1 above.

[0082] The technical details of the organic photoelectric conversion element will be explained in more detail below through the examples that have been put into practice. However, the embodiments shown below are for illustrative purposes only and do not limit the scope of rights.

[0083] <<Manufacturing of Organic Photoelectric Devices I>> <Example 1> After forming a 150nm thick lower electrode (anode) by sputtering ITO onto a glass substrate, a compound represented by chemical formula 1 shown below (manufactured by Fujifilm Corporation) is thermally deposited onto the lower electrode to form a lower buffer layer with a thickness of 5nm to 30nm, and a compound represented by chemical formula 2 shown below (p-type semiconductor material) and fullerene (C) are added. 60 A 100 nm thick organic photoelectric conversion layer is formed by co-depositing n-type semiconductor material in a volume ratio (thickness ratio) of 1:0.67 to 1:1. A 1.5 nm thick upper buffer layer is formed by thermal deposition of Yb onto an organic photoelectric conversion layer, and a 7 nm thick upper electrode (cathode) is formed by sputtering ITO. An organic photoelectric conversion element is manufactured by depositing aluminum oxide (Al2O3) to a thickness of 40 nm onto the upper electrode (cathode), and then sealing it with a glass plate. [ka] [ka]

[0084] <Example 2> An organic photoelectric conversion element is manufactured in the same manner as in Example 1, except that the compound represented by Chemical Formula 3 shown below is used as the p-type semiconductor material instead of the compound represented by Chemical Formula 2. [ka]

[0085] <Example 3> An organic photoelectric conversion element is manufactured in the same manner as in Example 1, except that the compound represented by Chemical Formula 4 shown below is used as the p-type semiconductor material instead of the compound represented by Chemical Formula 2. [ka]

[0086] <Example 4> An organic photoelectric conversion element is manufactured in the same manner as in Example 1, except that the compound represented by Chemical Formula 5 shown below is used as the p-type semiconductor material instead of the compound represented by Chemical Formula 2. [ka]

[0087] <<Photoelectric Properties Evaluation I>> A voltage of 3.0V was applied to the organic photoelectric conversion elements manufactured in Examples 1 to 4, and the wavelength-dependent external quantum efficiency (EQE) was evaluated and is shown in Figures 7 and 8. Figures 7 and 8 are graphs showing the photoelectric characteristics of the organic photoelectric conversion elements manufactured in Examples 1 to 4. Referring to Figures 7 and 8, it was confirmed that the organic photoelectric conversion elements of Examples 1 and 2 selectively absorb light in the green wavelength region and convert it into an electrical signal, the organic photoelectric conversion element of Example 3 selectively absorbs light in the blue wavelength region, and the organic photoelectric conversion element of Example 4 selectively absorbs light in the red wavelength region and converts it into an electrical signal.

[0088] <<Photoelectric Properties Evaluation II>> Using the organic photoelectric conversion elements manufactured in Examples 2, 3, and 4, the external quantum efficiency of image sensors having the structures shown in Figures 4 and 5 was calculated (simulated), and the results are shown in Figure 9. Figure 9 is a graph showing the photoelectric characteristics of the organic photoelectric conversion elements manufactured in Examples 2 to 4. Referring to Figure 9, it can be confirmed that in one embodiment of the present invention, the ratio of the maximum peak external quantum efficiency in the blue wavelength region to the maximum peak external quantum efficiency in the green wavelength region, and the ratio of the maximum peak external quantum efficiency in the red wavelength region to the maximum peak external quantum efficiency in the green wavelength region, are 0.5 or greater.

[0089] <<Manufacturing of Organic Photoelectric Devices II>> <Example 5> An organic photoelectric conversion element is manufactured in the same manner as in Example 1, except that the compound represented by chemical formula 6 shown below is used as the p-type semiconductor material instead of the compound represented by chemical formula 2, and the p-type semiconductor material and n-type semiconductor material are co-deposited in a volume ratio (thickness ratio) of 1:3 to 1:5. [ka]

[0090] <Example 6> An organic photoelectric conversion element is manufactured in the same manner as in Example 5, except that the compound represented by chemical formula 7 shown below is used as the p-type semiconductor material instead of the compound represented by chemical formula 6. [ka]

[0091] <<Photoelectric Properties Evaluation III>> A voltage of 10V was applied to the organic photoelectric conversion elements manufactured in Examples 5 and 6, and the wavelength-dependent external quantum efficiency (EQE) was evaluated and is shown in Figure 10. Figure 10 is a graph showing the photoelectric characteristics of the organic photoelectric conversion elements manufactured in Examples 5 and 6. Referring to Figure 10, it was confirmed that the organic photoelectric conversion elements of Examples 5 and 6 absorb light in the entire visible light wavelength range (for example, wavelengths above 400 nm and below 650 nm) and convert it into electrical signals.

[0092] <<Manufacturing of Organic Photoelectric Devices III>> <Example 7> An organic photoelectric conversion element is manufactured in the same manner as in Example 5, except that aluminum oxide (Al2O3) is deposited to a thickness of 40 nm on the upper electrode (cathode), and then an optical filter (manufactured by Fujifilm Corporation) having a compartment that selectively transmits light in the blue wavelength region and a compartment that selectively transmits light in the red wavelength region is additionally introduced. <Example 8> An organic photoelectric conversion element is manufactured in the same manner as in Example 7, except that the compound represented by chemical formula 6 is used as the p-type semiconductor material instead of the compound represented by chemical formula 5.

[0093] <<Photoelectric Properties Evaluation IV>> A voltage of 10V was applied to the organic photoelectric conversion elements manufactured in Examples 7 and 8, and the wavelength-dependent external quantum efficiency (EQE) was evaluated and is shown in Figure 11. Figure 11 is a graph showing the photoelectric characteristics of the organic photoelectric conversion elements manufactured in Examples 7 and 8. Referring to Figure 11, it was confirmed that the structures in Examples 7 and 8 selectively absorb light in the blue wavelength region and light in the red wavelength region and convert them into electrical signals.

[0094] Furthermore, the present invention is not limited to the embodiments described above. It can be modified and implemented in various ways without departing from the technical scope of the present invention. [Explanation of Symbols]

[0095] 1 Image Processing Device 2 Electronic equipment 10, 20 Image sensors 11-pixel array 12 Low Driver 13 Column Driver 14 Timing Controller 15. Lead-out circuit 10a, 10b, 10c (1st to 3rd pixels) 20a, 20b, 20c (blue, red, green) pixels 21 Input / Output Devices 22 memory 23 processors 24 ports 25 buses 30 object 40 Image Processors 100 First Organic Photoelectric Converter 110, 210 upper electrode 120 First Organic Photoelectric Conversion Layer 130, 230, 2230, 2330 Lower electrode 200 Second Organic Photoelectric Element 220 Second Organic Photoelectric Conversion Layer 300, 400 (1st, 2nd) optical filters 500 circuit boards 510 pixel circuit 610, 611, 612, 621, 622 Charge transfer path 621, 622 (1st, 2nd) charge transfer path 710 Lower insulating layer 720 Interlayer Insulation Layer 730 Upper insulating layer 800 Focusing Lens 900 transparent layer 2100, 2200, 2300 (Green, Blue, Red) Organic Photoelectric Converter 2120, 2220, 2320 Organic photoelectric conversion layer 2110, 2130, 2210, 2310 electrode PX pixels

Claims

1. A first organic photoelectric conversion element is positioned below the light incident surface and selectively absorbs light in a first wavelength region belonging to the visible light wavelength region and converts it into an electrical signal. An image sensor comprising: a second organic photoelectric conversion element disposed below the first organic photoelectric conversion element, which non-selectively absorbs light in the visible light wavelength range and converts it into an electrical signal; The first organic photoelectric conversion element and the second organic photoelectric conversion element are arranged on a substrate. The aforementioned substrate does not include a silicon-based photodiode. The first organic photoelectric conversion element and the second organic photoelectric conversion element each independently include an upper electrode, a lower electrode, and an organic photoelectric conversion layer disposed between the upper electrode and the lower electrode. The image sensor has a first section and a second section, The first section includes the first organic photoelectric conversion element, the second organic photoelectric conversion element, and a first optical filter disposed between the first organic photoelectric conversion element and the second organic photoelectric conversion element, which belongs to the visible light wavelength region and selectively transmits light in a second wavelength region different from the first wavelength region. The second compartment includes the first organic photoelectric conversion element, the second organic photoelectric conversion element, and a second optical filter disposed between the first organic photoelectric conversion element and the second organic photoelectric conversion element, which selectively transmits light in a third wavelength region that belongs to the visible light wavelength region and is different from the first and second wavelength regions. Each of the organic photoelectric conversion layers of the first organic photoelectric conversion element and the second organic photoelectric conversion element comprises at least one p-type semiconductor material and at least one n-type semiconductor material. Each of the first organic photoelectric conversion element and the second organic photoelectric conversion element independently contains one of the compounds represented by chemical formulas 2 to 7 shown below as the p-type semiconductor material. An image sensor characterized in that the organic photoelectric conversion layers of the first organic photoelectric conversion element and the second organic photoelectric conversion element each independently contain fullerene as the n-type semiconductor material. 【Chemistry 2】 【Transformation 3】 【Chemistry 4】 【Transformation 5】 【Transformation 6】 【Transformation 7】

2. The organic photoelectric conversion layer containing the compound represented by chemical formula 2 and the organic photoelectric conversion layer containing the compound represented by chemical formula 3 selectively absorb light in the green wavelength region and convert it into an electrical signal. The organic photoelectric conversion layer containing the compound represented by chemical formula 4 selectively absorbs light in the blue wavelength region and converts it into an electrical signal. The organic photoelectric conversion layer containing the compound represented by the chemical formula 5 selectively absorbs light in the red wavelength region and converts it into an electrical signal. The image sensor according to claim 1, wherein the organic photoelectric conversion layer containing the compound represented by chemical formula 6 and the organic photoelectric conversion layer containing the compound represented by chemical formula 7 absorb light in the entire wavelength range of visible light and convert it into an electrical signal.

3. The image sensor according to claim 1, characterized in that the first organic photoelectric conversion element selectively absorbs light in the green wavelength region and converts it into an electrical signal.

4. The image sensor according to claim 2, characterized in that the first optical filter selectively transmits light including the blue wavelength region.

5. The image sensor according to claim 3, characterized in that the second optical filter selectively transmits light including the red wavelength region.

6. The image sensor according to claim 1, characterized in that the content of the n-type semiconductor material in the second organic photoelectric conversion element is 1.0 times or more and 100.0 times or less than the content of the n-type semiconductor material in the first organic photoelectric conversion element.

7. The image sensor according to claim 1, characterized in that the first organic photoelectric conversion element has a volume ratio of the n-type semiconductor material to the p-type semiconductor material of 0.2 or more and 2.0 or less.

8. The image sensor according to claim 1, characterized in that the second organic photoelectric conversion element has a volume ratio of the n-type semiconductor material to the p-type semiconductor material of 2.0 or more and 20.0 or less.

9. The image sensor according to claim 1, further comprising a buffer layer disposed between the upper electrode and the organic photoelectric conversion layer, between the lower electrode and the organic photoelectric conversion layer, or a combination thereof.

10. The image sensor according to claim 9, characterized in that the buffer layer contains one or more elements selected from the group consisting of lanthanum elements, calcium (Ca), potassium (K), aluminum (Al), and alloys thereof.

11. The image sensor according to claim 9, characterized in that the buffer layer includes a compound represented by the following chemical formula B-1, a compound represented by the following chemical formula B-2, or a combination thereof. 【Chemical B-1】 【B-2】 (In the above chemical formula B-1 or B-2, M １ and M ２ Each of them operates independently, CR ｋ R ｌ , SiR ｍ R ｎ , NR ｏ , O, S, Se, or Te, Ar １ｂ ~Ar ４ｂ each independently represents a substituted or unsubstituted C6-C30 aryl group or a substituted or unsubstituted C3-C30 heteroaryl group, G ３ and G ４ Each is independent, single bond, -(CR ｐ R ｑ ) ｎ２ - (n² is an integer of 1 or 2), -O-, -S-, -Se-, -N=, -NR ｒ -, -SiR ｓ R ｔ -, or -GeR ｕ R ｖ - and R １ｂ ~R ８ｂ and R ｋ ~R ｖ Each of these is independently hydrogen, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C3-C30 heterocyclic group, a substituted or unsubstituted C1-C6 alkoxy group, a halogen, or a cyano group.

12. The lower electrode of the first organic photoelectric conversion element is electrically connected to the substrate through a charge transfer path. The image sensor according to claim 1, characterized in that the length of the charge transfer path is 150 nm or more and 1500 nm or less.

13. The image sensor according to claim 12, characterized in that the maximum aspect ratio of the charge transfer path is 1.0 or more and 15.0 or less.

14. The image sensor according to claim 1, further comprising an insulating layer disposed between the first organic photoelectric conversion element and the first optical filter, between the second organic photoelectric conversion element and the first optical filter, between the first organic photoelectric conversion element and the second optical filter, and between the second organic photoelectric conversion element and the second optical filter.

15. An image processing apparatus characterized by including an image sensor according to any one of claims 1 to 14.

16. An electronic device characterized by including an image sensor according to any one of claims 1 to 14.

17. A first section comprising a blue organic photoelectric conversion element having a blue organic photoelectric conversion layer at the bottom of the light incident surface that selectively absorbs light in the blue wavelength region and converts it into an electrical signal, and a green organic photoelectric conversion element having a green organic photoelectric conversion layer at the bottom of the blue organic photoelectric conversion element that selectively absorbs light in the green wavelength region and converts it into an electrical signal, which are sequentially stacked and arranged, An image sensor having a second section comprising a red organic photoelectric conversion element including a red organic photoelectric conversion layer at the bottom of the light incident surface that selectively absorbs light in the red wavelength region and converts it into an electrical signal, and a green organic photoelectric conversion element at the bottom of the red organic photoelectric conversion element that selectively absorbs light in the green wavelength region and converts it into an electrical signal, which are sequentially stacked and arranged, The aforementioned image sensor does not include a color filter. The ratio of the maximum peak external quantum efficiency in the blue wavelength region to the maximum peak external quantum efficiency in the green wavelength region, the ratio of the maximum peak external quantum efficiency in the red wavelength region to the maximum peak external quantum efficiency in the green wavelength region, or all of these are 0.5 or greater. The blue organic photoelectric element, the red organic photoelectric element, and the green organic photoelectric element are each arranged on a substrate. The first section and the second section are arranged adjacent to each other along the in-plane direction of the substrate, characterized in that the image sensor is provided for.

18. The blue organic photoelectric element, the green organic photoelectric element, and the red organic photoelectric element each independently include an upper electrode, a lower electrode, and the blue organic photoelectric layer, the green organic photoelectric layer, and the red organic photoelectric layer disposed between the upper electrode and the lower electrode. The image sensor according to claim 17, characterized in that the blue organic photoelectric conversion layer, the green organic photoelectric conversion layer, and the red organic photoelectric conversion layer each include at least one p-type semiconductor material and at least one n-type semiconductor material.

19. The image sensor according to claim 18, characterized in that the blue organic photoelectric conversion layer, the green organic photoelectric conversion layer, and the red organic photoelectric conversion layer of the blue organic photoelectric conversion element, respectively, each independently have a volume ratio of the n-type semiconductor material to the p-type semiconductor material of 0.2 or more and 2.0 or less.

20. The image sensor according to claim 18, wherein the blue organic photoelectric conversion layer of the blue organic photoelectric conversion element contains one or more selected from the group consisting of thiophene, thiophene derivatives, rubrene, rubrene derivatives, tetracene, tetracene derivative coumarin, and coumarin derivatives as the p-type semiconductor material.

21. The image sensor according to claim 18, characterized in that the green organic photoelectric conversion layer of the green organic photoelectric conversion element contains a compound represented by the following chemical formula A-1 as the p-type semiconductor material. 【Chemistry A-1】 (In the above chemical formula A-1, X is O, S, Se, Te, SO, SO ２ , or SiR ａ R ｂ And, Ar is a substituted or unsubstituted C6-C30 arylene group, a substituted or unsubstituted C3-C30 heterocyclic group, or two or more fusion rings selected from these. Ar １ａ and Ar ２ａ Each of these is independently a substituted or unsubstituted C6-C30 aryl group or a substituted or unsubstituted C3-C30 heteroaryl group. Ar １ａ and Ar ２ａ These elements either exist independently or combine with each other to form a fused ring. R １ａ ~R ３ａ , R ａ , and R ｂ Each of these is independently hydrogen, deuterium, a substituted or unsubstituted C1-C30 alkyl group, a substituted or unsubstituted C1-C30 alkoxy group, a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C3-C30 heteroaryl group, a halogen, a cyano group, or a combination thereof.

22. The image sensor according to claim 18, characterized in that the red organic photoelectric conversion layer of the red organic photoelectric conversion element contains metal-phthalocyanine or a metal-phthalocyanine derivative as the p-type semiconductor material.

23. The image sensor according to claim 18, characterized in that the blue organic photoelectric conversion layer, the green organic photoelectric conversion layer, and the red organic photoelectric conversion layer of the blue organic photoelectric conversion element red organic photoelectric conversion element, each independently contains one or more selected from the group consisting of metal-organic complexes, derivatives of metal-organic complexes, carboxylic acid anhydrides, derivatives of carboxylic acid anhydrides, perylenediimides, derivatives of perylenediimides, thiophenes, thiophene derivatives, fullerenes, and fullerene derivatives as the n-type semiconductor material.

24. The image sensor according to claim 18, characterized in that one or more of the blue organic photoelectric conversion layer, the green organic photoelectric conversion layer, and the red organic photoelectric conversion layer of the blue organic photoelectric conversion element, the green organic photoelectric conversion layer, and the red organic photoelectric conversion layer of each of the blue organic photoelectric conversion element, the green organic photoelectric conversion layer, and the red organic photoelectric conversion layer respectively contains fullerene as an n-type semiconductor material.

25. The first and second sections are arranged on the substrate. The lower electrode of the blue organic photoelectric conversion element is connected to the substrate through a first charge transfer path. The lower electrode of the red organic photoelectric conversion element is connected to the substrate through a second charge transfer path. The image sensor according to claim 18, characterized in that the lengths of the first charge transfer path and the second charge transfer path are each independently 50 nm or more and 500 nm or less.

26. The image sensor according to claim 25, characterized in that the substrate does not include a silicon-based photodiode.

27. The image sensor according to claim 25, characterized in that the maximum aspect ratio of the first charge transfer path and the second charge transfer path is independently 0.5 or more and 10.0 or less.

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