WO2014192274A1 - 有機光電変換素子および撮像素子 - Google Patents

有機光電変換素子および撮像素子 Download PDF

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WO2014192274A1
WO2014192274A1 PCT/JP2014/002746 JP2014002746W WO2014192274A1 WO 2014192274 A1 WO2014192274 A1 WO 2014192274A1 JP 2014002746 W JP2014002746 W JP 2014002746W WO 2014192274 A1 WO2014192274 A1 WO 2014192274A1
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film
photoelectric conversion
organic
layer
protective film
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PCT/JP2014/002746
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English (en)
French (fr)
Japanese (ja)
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真二 今井
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富士フイルム株式会社
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    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K39/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic radiation-sensitive element covered by group H10K30/00
    • H10K39/30—Devices controlled by radiation
    • H10K39/32—Organic image sensors
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K30/00—Organic devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation
    • H10K30/80—Constructional details
    • H10K30/88—Passivation; Containers; Encapsulations
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/549—Organic PV cells
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

  • the present invention relates to an organic photoelectric conversion element formed by laminating a photoelectric conversion layer made of an organic material on a plurality of pixel electrodes, which is used for an imaging device, a display device, and the like. Further, the present invention relates to an imaging device provided with an organic photoelectric conversion device.
  • Image sensors such as CCD sensors and CMOS sensors are widely known as image sensors used in digital still cameras, digital video cameras, cameras for mobile phones, cameras for endoscopes, and the like.
  • imaging devices having a photoelectric conversion layer made of an organic material have been studied.
  • An imaging device having an organic photoelectric conversion layer includes a pixel electrode formed on a semiconductor substrate on which a signal readout circuit is formed, an organic photoelectric conversion layer formed on the pixel electrode, and an organic photoelectric conversion layer A transparent counter electrode (upper electrode), a protective film formed on the counter electrode to protect the counter electrode, and a color filter or the like.
  • a protective film is formed on the organic photoelectric conversion layer by low temperature plasma CVD at about room temperature to 80 ° C. in order to prevent deterioration of the organic layer due to penetration of oxygen or water. It is known to do (patent document 2).
  • Patent Document 2 discloses a photoelectric conversion film-stacked solid-state imaging device using an organic semiconductor, in which a protective layer made of an inorganic material is formed above the transparent counter electrode.
  • the inorganic material constituting the protective layer is made of silicon oxide, silicon nitride, or silicon nitride oxide, and is formed by plasma CVD capable of forming a film at a low temperature (ordinary temperature).
  • Patent Document 3 proposes an imaging device in which the film stress is suppressed to ⁇ 200 MPa to 250 MPa by forming the protective film from a plurality of layers of different film stresses.
  • Patent Document 4 proposes an imaging device in which a layer having an internal stress of 100 MPa or less is provided between the counter electrode and the sealing film (protective film) as a sealing auxiliary layer.
  • Patent Document 5 As an element having an organic layer and an electrode, not only an imaging element but also an organic EL element in which an organic light emitting material is disposed between a pair of electrodes facing each other on a substrate is known (see Patent Document 5).
  • the organic EL element described in Patent Document 5 has a protective layer corresponding to a sealing film on the surface of the organic light emitting material, and the protective layer is formed by laminating layers different in stress generated inside. Relieves the internal stress of the protective layer.
  • JP, 2011-71469 A Unexamined-Japanese-Patent No. 2006-245045 JP 2011-228648 A JP 2012-124343 A Japanese Patent Application Publication No. 2001-284042
  • the stress of the entire protective film is reduced by forming the protective film with a laminated film of silicon oxynitride (SiON) having compressive stress and aluminum oxide (AlO) having tensile stress.
  • SiON silicon oxynitride
  • AlO aluminum oxide
  • Silicon oxynitride can form a thick film in a relatively short time, but aluminum oxide takes time to form a thick film, and forming both layers with the same thickness is inferior in mass productivity. There is.
  • soldering a component such as a photoelectric conversion element
  • solder paste is printed on a printed circuit board, parts are placed on it, and the solder is melted and heated by heating from 220 ° C to 260 ° C for about 10 seconds. I do.
  • an organic photoelectric conversion element having a configuration that can withstand the reflow including the high temperature heating step is required.
  • the present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an organic photoelectric conversion element and an imaging element provided with the organic photoelectric conversion element, which have high mass productivity and can reduce manufacturing costs. I assume.
  • the organic photoelectric conversion device of the present invention is A substrate, A plurality of pixel electrodes spaced apart from each other on the substrate; An organic film including a photoelectric conversion layer disposed in a continuous film shape on a plurality of pixel electrodes and between the pixel electrodes; A counter electrode disposed on the organic film, And a protective film disposed on the counter electrode,
  • the step between the upper surface of the pixel electrode and the surface of the substrate is 3 nm or more and 100 nm or less,
  • the inclination angle of the end of the pixel electrode is 10 ° or more and 90 ° or less
  • the internal stress of the protective film is -600 MPa or more and less than -200 MPa,
  • the product of the film thickness of the protective film and the internal stress is ⁇ 40,000 MPa ⁇ nm or more and less than ⁇ 14,000 MPa ⁇ nm.
  • the protective film is preferably composed of an aluminum oxide layer and a silicon oxynitride layer.
  • the thickness of the aluminum oxide layer is preferably 1 ⁇ 5 or less of the total thickness of the protective film. At this time, the thickness of the aluminum oxide layer is more preferably 10 nm or less.
  • the protective film may be composed of only a silicon oxynitride layer. At this time, a plurality of layers having different oxygen and nitrogen ratios in the silicon oxynitride layer (SiOxNy) may be included.
  • the internal stress of the protective film is more preferably -400 MPa or more and less than -200 MPa.
  • the inclination angle of the end of the pixel electrode is more preferably 30 ° or more and 90 ° or less.
  • the level difference between the pixel electrode and the substrate surface is more preferably 5 nm or more and 40 nm or less.
  • the imaging device of the present invention is characterized by having the organic photoelectric conversion device of the present invention.
  • the step between the upper surface of the pixel electrode and the surface of the substrate is 3 nm or more and 100 nm or less, and the inclination angle of the end of the pixel electrode is 10 ° or more and 90 ° or less Since the internal stress of the film is -600 Pa or more and less than -200 MPa, even after the high temperature processing (about 10 seconds at 220 ° C. to 260 ° C.) at the time of solder reflow while sufficiently securing the protective function of the organic film by the protective film. Mechanical degradation of the organic film can be suppressed.
  • the absolute value of the internal stress of the protective film is larger than that of the prior art, it is possible to select a protective film made of a material that can be easily deposited.
  • a protective film mainly using silicon oxynitride film formation is easy and mass productivity is high.
  • the film forming time can be set to a practical range as long as the thickness is sufficiently thin with respect to the total thickness of the protective film.
  • the pixel portion in which at least the pixel electrodes are arrayed by setting the step difference from the substrate surface of the pixel electrode to 3 nm or more and 100 nm or less and the inclination angle of the end portion to 10 ° or more and 90 ° or less as in the present invention.
  • the present inventors have found that the generation of wrinkles can be suppressed even at a heating temperature of about 240 ° C. for about 10 seconds.
  • pewter reflow since the reflow apparatus for normal electric devices can be used, the cost of a manufacturing apparatus can be suppressed. Further, Pb-free solder which does not contain Pb, which has a large environmental load, can be used.
  • FIG. 1 is a schematic cross-sectional view showing the configuration of the photoelectric conversion element 1 according to the embodiment of the present invention.
  • the imaging device 1 of the present embodiment includes a plurality of pixel electrodes 4 arranged in a two-dimensional manner spaced apart from each other on a substrate 2, and a plurality of pixel electrodes 4 and continuous on the pixel electrodes.
  • the film is formed to cover the organic film 7 including at least the photoelectric conversion layer, the counter electrode 8 disposed on the organic film 7, and the counter electrode 8 disposed in a film shape, and is formed under the film.
  • a protective film 10 covering the pixel electrode 4.
  • the substrate 2 is made of, for example, a silicon substrate, a glass substrate or the like.
  • the pixel electrode 4 is an electrode provided independently for each pixel.
  • FIG. 2 is a view for explaining the end inclination angle ⁇ of the pixel electrode and the level difference t.
  • Each pixel electrode 4 has an end (a taper portion) inclined at an angle ⁇ (where 10 ° ⁇ ⁇ ⁇ 90 °) with respect to the surface 2 a of the substrate 2. If the inclination angle of the end portion of each pixel electrode 4 is in the range of 10 ° to 90 °, they may be individually different.
  • the inclination angle ⁇ is more preferably 30 ° or more and 90 ° or less. When the inclination angle is larger than 90 °, the deposition beam is broken at the electrode end when depositing the organic photoelectric conversion layer, and a point defect occurs in the image.
  • the difference in level t between the upper surface 4 a of each pixel electrode 4 and the surface 2 a of the substrate 2 is 3 nm ⁇ t ⁇ 100 nm.
  • the level difference t is more preferably 5 nm or more and 40 nm or less.
  • the step difference t exceeds 100 nm and becomes higher than the thickness of the electron blocking layer, the dark current increases.
  • the step t is the thickness of the pixel electrode 4 itself.
  • the step t is smaller than the thickness of the pixel electrode 4.
  • Examples of the material of the pixel electrode 4 include metals, metal oxides, metal nitrides, metal borides, organic conductive compounds, and mixtures thereof.
  • conductive metal oxides such as tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO), indium tungsten oxide (IWO), titanium oxide, titanium nitride (TiN)
  • Metals such as gold (Au), platinum (Pt), silver (Ag), chromium (Cr), nickel (Ni), aluminum (Al), etc., and further, these metals and conductive metal oxides And laminates, organic conductive compounds such as polyaniline, polythiophene and polypyrrole, laminates of these with ITO, and the like.
  • Particularly preferable materials for the pixel electrode 4 are titanium nitride, molybdenum nitride, tantalum nitride, and tungsten nitride.
  • the organic film 7 includes a photoelectric conversion layer made of an organic photoelectric conversion material that generates an electric charge according to at least the received light, or an organic photoelectric conversion material that emits light by application of an electric field. It consists of Note that a layer made of an inorganic material may be included between the plurality of organic layers.
  • the counter electrode 8 is an electrode that faces each pixel electrode 4 and is provided on the organic film 7.
  • the counter electrode 8 is commonly provided to a plurality of pixels, and may therefore be called a common electrode (common electrode).
  • the counter electrode 8 may be individually provided in correspondence with each pixel electrode.
  • the counter electrode 8 has a wavelength at which the photoelectric conversion layer has sensitivity or a wavelength of emitted light, for example, visible light, in order to cause light to enter the organic film 7 including the photoelectric conversion layer or transmit emitted light. It is transparent enough.
  • a transparent conductive oxide is preferably used for the counter electrode 8.
  • metals, metal oxides, metal nitrides, metal borides, organic conductive compounds, mixtures thereof and the like can be mentioned. Specific examples thereof include conductive metal oxides such as tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO), indium tungsten oxide (IWO), titanium oxide, etc., metal nitrides such as TiN, etc.
  • Metals such as gold (Au), platinum (Pt), silver (Ag), chromium (Cr), nickel (Ni), aluminum (Al), and mixtures or laminates of these metals and conductive metal oxides , Organic conductive compounds such as polyaniline, polythiophene and polypyrrole, laminates of these with ITO, and the like.
  • Particularly preferable materials for the transparent conductive film are ITO, IZO, tin oxide, antimony-doped tin oxide (ATO), fluorine-doped tin oxide (FTO), zinc oxide, antimony-doped zinc oxide (AZO), gallium-doped zinc oxide GZO) is any material.
  • the light transmittance of the counter electrode 8 is preferably 60% or more, more preferably 80% or more, more preferably 90% or more, more preferably 95% or more at the visible light wavelength.
  • the counter electrode 8 preferably has a thickness of 5 to 30 nm. By setting the thickness of the counter electrode 8 to 5 nm or more, the lower layer can be sufficiently covered, and uniform performance can be obtained. On the other hand, when the film thickness of the counter electrode 8 exceeds 30 nm, the counter electrode 8 and the pixel electrode 4 may locally short-circuit, and the dark current may increase. By setting the thickness of the counter electrode 8 to 30 nm or less, the occurrence of local short circuit can be suppressed.
  • the protective film 10 is for preventing the factor which degrades organic materials, such as water and oxygen, from invading the organic film 7 containing the organic material, and the organic film 7 is used over a long period of storage and long term use. Prevent the deterioration of the organic materials, such as water and oxygen, from invading the organic film 7 containing the organic material, and the organic film 7 is used over a long period of storage and long term use. Prevent the deterioration of the
  • the protective film 10 may be a single layer or a plurality of layers. Here, all the insulating layers formed on the counter electrode 8 are integrally referred to as the protective film 10.
  • the internal stress of the protective film 10 is -600 MPa or more and less than -200 MPa, and more preferably -400 MPa or more and less than -200 MPa.
  • the protective film 10 is preferably composed of an inorganic oxide layer, and particularly preferably composed of only silicon oxynitride (SiON) or a laminate of silicon oxynitride and aluminum oxide (AlO).
  • Aluminum oxide has a very high barrier property, but since it takes a considerable time to form a thick film, it is inferior in mass productivity to form a film having a thickness sufficient to exert a sufficient protective function as a protective film.
  • silicon oxynitride is easy to form a thick film, but its compressive stress is very large.
  • the aluminum oxide film has a tensile stress with respect to the substrate, and the silicon oxynitride film has a compressive stress.
  • the film thickness of aluminum oxide is 1 ⁇ 5 or less of the total thickness of the protective film, the compressive stress of the silicon oxynitride film becomes dominant as the internal stress of the protective film.
  • the internal stress due to the protective film be smaller and that the absolute value be 200 MPa or less.
  • the protective film 10 has a stress of -600 MPa or more and less than -200 MPa, and more preferably -400 MPa or more and less than -200 MPa.
  • the protective film 10 of the present invention has a stress greater than that of the prior art, but the internal stress of the protective film is -600 MPa by setting the inclination angle of the step and the end face from the substrate surface of the pixel electrode to the above range. As described above, the inventor has found that it is possible to suppress wrinkles even if the pressure is less than -200 MPa (see Examples described later).
  • the thickness of the protective film 10 is preferably 70 to 500 nm. If the protective film 110 has a thickness of 70 nm or more, the organic film can be sufficiently protected from immersion by an acid, an alkali, or the like, and if 500 nm or less, the occurrence of color mixing can be suppressed.
  • the product of the film thickness of the protective film 10 and the internal stress is made to be ⁇ 40,000 MPa ⁇ nm or more and less than ⁇ 14,000 MPa ⁇ nm. If the absolute value of the product of the film thickness and the internal stress is 40,000 or less, the effect of suppressing wrinkles due to the presence of the pixel electrode described above is effective.
  • the protective film 110 is formed, for example, by a vapor deposition method.
  • the vapor deposition method include plasma CVD method, atomic layer deposition CVD method, sputtering method and ion plate method.
  • the protective film 110 is also transparent to incident light or emitted light.
  • the internal stress is measured by the following measuring method, but the stress of the protective film is formed by the same material as the film measured by the following measuring method and under the same film forming conditions. It means that.
  • a method of measuring stress from the warpage of the substrate 70 caused by the thin film 72 will be described by taking the substrate 70 on which the thin film 72 is formed as an example.
  • the internal stress of the thin film 72 can be measured using an optical lever method based on the amount of warpage of the substrate 70.
  • FIG. 3 is a schematic view showing a measuring apparatus for measuring the amount of warpage of a substrate on which a thin film is formed.
  • the measuring apparatus 200 illustrated in FIG. 3 includes a laser irradiation unit 202 that emits a laser beam, a splitter 204 that reflects part of the light emitted from the laser irradiation unit 202 and transmits other light, And a mirror 206 for reflecting the light transmitted through the light source 204.
  • a thin film 72 which is an object to be measured is formed on one surface of the substrate 70.
  • the measuring apparatus 200 by measuring the amount of warpage before and after the thin film is formed on the substrate, the amount of warpage caused by the formation of the thin film can be obtained.
  • the procedure of measuring the stress of the thin film by the measuring device 200 will be described.
  • a thin film stress measuring apparatus FLX-2320-S manufactured by Toago Technology, Inc. can be used as an apparatus used for the measurement.
  • the measurement conditions when this device is used are shown below.
  • Laser beam Laser irradiation unit 202
  • Laser used KLA-Tencor-2320-S Laser power: 4mW
  • Laser wavelength 670 nm
  • Scanning speed 30 mm / s
  • Substrate material Silicon (Si) Orientation: ⁇ 100>
  • Type P type (dopant: Boron)
  • Thickness 250 ⁇ 25 ⁇ m or 280 ⁇ 25 ⁇ m
  • the curvature amount of the substrate 70 on which the thin film 72 is formed is measured in advance, and the curvature radius R1 of the substrate 70 is obtained. Subsequently, the thin film 72 is formed on one surface of the substrate 70, the amount of warpage of the substrate 70 on which the thin film 72 is formed is measured, and the curvature radius R2 is determined.
  • the amount of warpage is scanned with the laser on the side of the substrate 70 on which the thin film 72 is formed, and the amount of warpage is calculated from the reflection angle of the laser light reflected from the substrate 70.
  • the curvature radius R R1 ⁇ R2 / (R1-R2) is calculated based on the amount of warpage.
  • the stress of the thin film 72 is calculated by the following formula.
  • the unit of stress of the thin film 72 is represented by Pa. When it is compressive stress, it shows a negative value, and when it is tensile stress, it shows a positive value.
  • the method of measuring the stress of the thin film 72 is not particularly limited, and any known method can be used.
  • the method of measuring the internal stress of the thin film is as described above.
  • that the internal stress of the protective film is -600 MPa or more and less than -200 MPa means that the composition and film forming conditions of the film in which the internal stress measured by the above measuring method is -600 MPa or more and less than -200 MPa Is previously determined, which means that the film is formed under the conditions.
  • the stress of the protective film can be changed by adjusting the substrate temperature, pressure, input power, gas type, inter-substrate distance, and the like, for example, when forming a film by CVD or sputtering.
  • the photoelectric conversion element as described above When the photoelectric conversion element as described above is provided with a photoelectric conversion layer that receives light and generates electric charge, when light is incident from above the counter electrode 8 with the counter electrode 8 as an electrode on the light incident side, Light passes through the counter electrode 8 and is incident on the photoelectric conversion layer of the organic film 7 to generate charges in the photoelectric conversion layer. The holes among the generated charges move to the pixel electrode 4. By converting the holes moved to the pixel electrode 4 into a voltage signal corresponding to the amount and reading the light, light can be converted into a voltage signal and extracted.
  • the photoelectric conversion element includes a photoelectric conversion layer that converts an electrical signal into light, a light emitting element that converts a voltage signal (electric field) applied between the pixel electrode 4 and the counter electrode 8 into light. Can be used as a so-called EL element.
  • FIG. 4 is a schematic cross-sectional view showing an imaging device according to an embodiment of the present invention.
  • the imaging device according to the embodiment of the present invention can be used in an imaging device such as a digital camera or a digital video camera. Furthermore, it is mounted and used for imaging modules, such as an electronic endoscope and a mobile telephone.
  • the solid-state imaging device 100 shown in FIG. 4 includes a substrate 101, an insulating layer 102, a connection electrode 103, a pixel electrode 104, a connection portion 105, a connection portion 106, an organic film 107, a counter electrode 108, and protection.
  • the film 110, the color filter 111, the partition wall 112, the light shielding layer 113, the surface protection layer 114, the counter electrode voltage supply unit 115, and the readout circuit 116 are provided.
  • the pixel electrode 104, the organic film 107, the counter electrode 108 and the protective film 110 in the solid-state imaging device 100 correspond to the pixel electrode 4, the organic film 7, the counter electrode 8 and the protective film 10 of the photoelectric conversion element 1 described above. It is a thing.
  • the substrate 101 is a glass substrate or a semiconductor substrate such as Si.
  • An insulating layer 102 is formed on the substrate 101.
  • a plurality of pixel electrodes 104 two-dimensionally arranged in a state where the surface is viewed vertically are formed.
  • the connection electrode 103 is formed on the insulating layer 102.
  • the connection electrode 103 and the plurality of pixel electrodes 104 are respectively located on the surface of the insulating layer 102, and the lower surface of the connection electrode 103 and the lower surface of each pixel electrode 104 are substantially flush with the surface of the insulating layer 102.
  • the pixel electrode 104 is a charge collection electrode for collecting a charge generated in an organic photoelectric conversion layer (hereinafter, also simply referred to as a photoelectric conversion layer) of the organic film 107 described later.
  • a readout circuit 116 connected to each of the plurality of pixel electrodes 104 and a counter electrode voltage supply unit 115 connected to the connection electrode 103 are formed.
  • the organic film 107 is formed on the insulating layer 102 and each pixel electrode 104.
  • the organic film 107 includes a photoelectric conversion layer.
  • the photoelectric conversion layer is a layer that generates charge by photoelectrically converting incident light.
  • the organic film 107 is provided on the plurality of pixel electrodes 104 so as to cover them.
  • the organic film 107 has a constant film thickness on the pixel electrode 104, but the film thickness may be changed outside the pixel portion (outside the effective pixel region). Details of the organic film 107 will be described later. Note that the organic film 107 may include not only a layer made of only an organic material but also a layer of an inorganic material.
  • the counter electrode 108 is an electrode facing the pixel electrode 104, and is provided on the organic film 107 so as to cover the organic film 107.
  • the counter electrode 108 is made of a conductive material that is transparent to incident light in order to cause light to be incident on the organic film 107.
  • the counter electrode 108 is provided on the organic film 107, and is formed on the insulating layer 102 so as to extend on the connection electrode 103 disposed outside the outer peripheral edge of the organic film 107. Connected.
  • connection portions 105 and 106 are embedded in the insulating layer 102.
  • the connection portion 105 electrically connects the pixel electrode 104 and the readout circuit 116.
  • the connection unit 106 electrically connects the connection electrode 103 and the counter electrode voltage supply unit 115.
  • the connection portions 105 and 106 are columnar members made of a conductive material, and are, for example, via plugs.
  • the counter electrode voltage supply unit 115 is formed on the substrate 101, and applies a predetermined voltage to the counter electrode 108 through the connection portion 106 and the connection electrode 103.
  • the power supply voltage is boosted by a charge pump or other not shown booster circuit to supply the predetermined voltage.
  • the readout circuit 116 is provided on the substrate 101 to correspond to each of the plurality of pixel electrodes 104.
  • the readout circuit 116 reads out a signal corresponding to the charge collected by the pixel electrode 104.
  • the readout circuit 116 is configured by a CMOS circuit.
  • the readout circuit 116 is shielded from light by a light shielding layer (not shown) provided on the insulating layer 102.
  • a CCD or CMOS circuit it is preferable to employ a CCD or CMOS circuit. From the viewpoint of high speed, it is preferable to use a CMOS circuit.
  • the readout circuit 116 may be configured of a CCD circuit, a TFT circuit, or the like.
  • a protective film 110 is formed on the counter electrode 108.
  • the protective film 110 blocks oxygen and water from entering the organic film 107 by shielding oxygen and water.
  • the protective film 110 may be composed of a plurality of layers. Further, the internal stress of the entire protective film 110 is within a predetermined range.
  • a plurality of color filters 111 two-dimensionally arranged are formed on the protective film 110.
  • the plurality of color filters 111 are formed above the respective pixel electrodes 104.
  • the partition wall 112 is formed in a lattice shape, isolates adjacent color filters 111, and can suppress incident light from entering the color filters of other pixel portions, and the light transmission efficiency of each pixel portion Improve.
  • the light shielding layer 113 is formed on the protective film 110 except the area where the color filter 111 and the partition wall 112 are provided. Thus, the light shielding layer 113 prevents light from entering the region covering the region other than the region where the plurality of pixel electrodes 104 are arranged in the organic film 107.
  • the surface protective layer 114 is formed to cover the color filter 111, the partition wall 112, and the light shielding layer 113, and protects the surface on the light incident side in the imaging device.
  • connection electrodes 103, a plurality of connection portions 106, and a plurality of counter electrode voltage supply portions 115 may be provided, or one each.
  • the counter electrode 108 is provided as a control with respect to the center of the counter electrode 108, and a voltage is supplied to the counter electrode 108 from each counter electrode voltage supply unit 115. Voltage drop can be suppressed.
  • a region including at least one pixel electrode 104, the organic film 107, and the counter electrode 108 facing the pixel electrode 104 can be defined as one pixel portion.
  • the imaging device 100 is configured by arranging a plurality of pixel units in an array.
  • the organic film 107 may include a charge blocking layer in addition to the photoelectric conversion layer.
  • the charge blocking layer has a function of suppressing dark current.
  • the charge blocking layer may be composed of a plurality of layers, for example, may be composed of a first blocking layer and a second blocking layer. As described above, by forming the charge blocking layer into a plurality of layers, an interface is formed between the first blocking layer and the second blocking layer, and a discontinuity occurs in the intermediate level present in each layer, whereby the intermediate layer is formed. It becomes difficult for charge carriers to move through the levels, and dark current can be suppressed. Note that the charge blocking layer may be a single layer.
  • the photoelectric conversion layer includes a p-type organic semiconductor and an n-type organic semiconductor.
  • the exciton dissociation efficiency can be increased by bonding a p-type organic semiconductor and an n-type organic semiconductor to form a donor-acceptor interface. For this reason, the photoelectric conversion layer of the structure which joined the p-type organic semiconductor and the n-type organic semiconductor expresses high photoelectric conversion efficiency.
  • a photoelectric conversion layer in which a p-type organic semiconductor and an n-type organic semiconductor are mixed is preferable because the junction interface is increased and the photoelectric conversion efficiency is improved.
  • the p-type organic semiconductor is a donor-type organic semiconductor, mainly represented by a hole-transporting organic compound, and refers to an organic compound having a property of easily giving an electron. More specifically, it refers to an organic compound having a smaller ionization potential when used in contact with two organic materials. Therefore, as the dona organic compound, any organic compound having an electron donating property can be used.
  • the metal complex etc. which it has as can be used.
  • the present invention is not limited to this, and as described above, any organic compound having a smaller ionization potential than the organic compound used as the n-type (acceptor property) compound may be used as the donor
  • An n-type organic semiconductor is an acceptor-type organic semiconductor, mainly represented by an electron transporting organic compound, and refers to an organic compound having a property of easily accepting an electron. More specifically, an n-type organic semiconductor refers to an organic compound having a larger electron affinity when used in contact with two organic compounds. Therefore, as the acceptor type organic compound, any organic compound can be used as long as it is an electron accepting organic compound.
  • fused aromatic carbocyclic compounds naphthalene derivative, anthracene derivative, phenanthrene derivative, tetracene derivative, pyrene derivative, perylene derivative, fluoranthene derivative
  • 5- to 7-membered heterocyclic compound containing nitrogen atom, oxygen atom, sulfur atom Eg pyridine, pyrazine, pyrimidine, pyridazine, triazine, quinoline, quinoxaline, quinazoline, quintaline, phthalazine, cinnoline, isoquinoline, pteridine, acridine, phenazine, phenanthroline, tetrazole, pyrazole, imidazole, thiazole, oxazole, indazole, benzimidazole, benzotriazole, Benzoxazole, benzothiazole, carbazole, purine, triazolopyridazine, triazolopyrim
  • Any organic dye may be used as the p-type organic semiconductor or n-type organic semiconductor, but preferably, cyanine dyes, styryl dyes, hemicyanine dyes, merocyanine dyes (including zero methine merocyanine (simple merocyanine)), 3 Nuclear merocyanine dyes, tetranuclear merocyanine dyes, rhodacyanine dyes, complex cyanine dyes, complex merocyanine dyes, allopolar dyes, oxonol dyes, hemioxonol dyes, squalium dyes, croconium dyes, azomethine dyes, coumarin dyes, arylidene dyes, anthraquinone dyes, tri Phenylmethane dyes, azo dyes, azomethine dyes, spiro compounds, metallocene dyes, fluorenone dyes, fulgide dyes, pery
  • fullerene or a fullerene derivative excellent in electron transportability As the n-type organic semiconductor, it is particularly preferable to use a fullerene or a fullerene derivative excellent in electron transportability.
  • fullerenes fullerenes, 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 240 , fullerene C 540 , mixed A fullerene, a fullerene nanotube is represented, and a fullerene derivative represents the compound to which the substituent was added to these.
  • the substituent of the fullerene derivative is preferably an alkyl group, an aryl group or a heterocyclic group.
  • the alkyl group is more preferably an alkyl group having 1 to 12 carbon atoms, and the aryl group and the heterocyclic group are preferably a benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, fluorene ring, triphenylene ring, naphthacene ring , Biphenyl ring, pyrrole ring, furan ring, thiophene ring, imidazole ring, oxazole ring, thiazole ring, pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring, indolizine ring, indole ring, benzofuran ring, benzothiophene ring, isobenzofuran Ring, benzimidazo
  • substituents may further have a substituent, and the substituent may combine to form a ring as much as possible.
  • the substituent may have a plurality of substituents, and they may be the same or different. Also, a plurality of substituents may be combined as much as possible to form a ring.
  • the photoelectric conversion layer contains a fullerene or a fullerene derivative
  • electrons generated by photoelectric conversion can be rapidly transported to the pixel electrode 104 or the counter electrode 108 through the fullerene molecule or the fullerene derivative molecule.
  • a fullerene molecule or a fullerene derivative molecule is linked to form an electron path, electron transportability is improved, and high speed responsiveness of the photoelectric conversion element can be realized.
  • it is preferable that 40% or more of the fullerene or the fullerene derivative is contained in the photoelectric conversion layer.
  • the amount of the fullerene or the fullerene derivative is too large, the amount of the p-type organic semiconductor decreases, the junction interface becomes small, and the exciton dissociation efficiency decreases.
  • the fullerene or fullerene derivative contained in the photoelectric conversion layer preferably has a composition of 85% or less.
  • An electron donating organic material can be used for the first blocking layer and the second blocking layer.
  • low molecular weight materials such as N, N'-bis (3-methylphenyl)-(1,1'-biphenyl) -4,4'-diamine (TPD) and 4,4'-bis [N Aromatic diamine compounds such as-(naphthyl) -N-phenyl-amino] biphenyl ( ⁇ -NPD), oxazole, oxadiazole, triazole, imidazole, imidazolone, stilbene derivative, pyrazoline derivative, tetrahydroimidazole, polyarylalkane, butadiene 4,4 ', 4 "-tris (N- (3-methylphenyl) N-phenylamino) triphenylamine (m-MTDATA), porphine, tetraphenylporphine copper, phthalocyanine, copper phthalocyanine, titanium phthalocyanine oxide, etc.
  • Porphyrin compound, triazole derivative, oxa Use of zazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, silazane derivatives, etc.
  • polymers such as phenylene vinylene, fluorene, carbazole, indole, pyrene, pyrrole, picoline, thiophene, acetylene, diacetylene and derivatives thereof can be used, even if it is not an electron donating compound, It is possible to use a compound having sufficient hole transportability.
  • An inorganic material can also be used as the charge blocking layer.
  • the inorganic material has a dielectric constant larger than that of the organic material, when it is used for the charge blocking layer, a large voltage is applied to the photoelectric conversion layer, and the photoelectric conversion efficiency can be increased.
  • Materials that can be a charge blocking layer include calcium oxide, chromium oxide, chromium oxide copper, manganese oxide, cobalt oxide, nickel oxide, copper oxide, gallium oxide, gallium oxide, strontium oxide, niobium oxide, molybdenum oxide, indium oxide copper, oxide There are indium silver, iridium oxide and the like.
  • the layer adjacent to the photoelectric conversion layer among the plurality of layers is a layer made of the same material as the p-type organic semiconductor contained in the photoelectric conversion layer.
  • the same p-type organic semiconductor as the charge blocking layer, formation of an intermediate level at the interface between the photoelectric conversion layer and the layer adjacent thereto can be suppressed, and dark current can be further suppressed.
  • the charge blocking layer is a single layer, it can be a layer consisting of an inorganic material, or, in the case of multiple layers, one or more layers can be a layer consisting of an inorganic material .
  • the pixel electrode 104 collects charges of electrons or holes generated in the organic film 107 including the photoelectric conversion layer on the pixel electrode 104.
  • the charge collected by each pixel electrode 104 becomes a signal in the readout circuit 116 of each corresponding pixel, and an image is synthesized from the signals acquired from a plurality of pixels.
  • the details of the pixel electrode 104 are the same as those described for the photoelectric conversion element 1, and the thickness from the surface of the substrate (here, the surface of the insulating layer 102) is 3 nm or more and 100 nm or less, preferably 5 nm or more and 40 nm
  • the angle ⁇ of the end portion is 10 ° or more and 90 ° or less, preferably 30 ° or more and 90 ° or less.
  • the counter electrode 108 applies an electric field to the organic film 107 by sandwiching the organic film 107 including the photoelectric conversion layer together with the pixel electrode 104, and collects the charges generated in the photoelectric conversion layer with the pixel electrode 104. It collects charge with the opposite polarity to the signal charge.
  • the counter electrode 108 can be shared by a plurality of pixels because it is not necessary to divide the collection of the reverse polarity charge among the pixels. Therefore, it may be called a common electrode (common electrode).
  • the counter electrode 108 is preferably made of a transparent conductive film in order to allow light to be incident on the organic film 107 including the photoelectric conversion layer, and for example, metal, metal oxide, metal nitride, metal boride, organic conductive property Compounds, mixtures thereof and the like can be mentioned. Specific examples thereof include conductive metal oxides such as tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO), indium zinc oxide (IZO), indium tungsten oxide (IWO), titanium oxide, etc., metal nitrides such as TiN, etc.
  • Metals such as gold (Au), platinum (Pt), silver (Ag), chromium (Cr), nickel (Ni), aluminum (Al), and mixtures or laminates of these metals and conductive metal oxides , Organic conductive compounds such as polyaniline, polythiophene and polypyrrole, laminates of these with ITO, and the like.
  • Particularly preferable materials for the transparent conductive film are ITO, IZO, tin oxide, antimony-doped tin oxide (ATO), fluorine-doped tin oxide (FTO), zinc oxide, antimony-doped zinc oxide (AZO), gallium-doped zinc oxide GZO) is any material.
  • the surface resistance of the counter electrode 108 is preferably 10 k ⁇ / ⁇ or less, more preferably 1 k ⁇ / ⁇ or less, when the readout circuit 116 is a CMOS type.
  • the readout circuit 116 is a CCD type, 1 k ⁇ / ⁇ or less is preferable, and more preferably 0.1 k ⁇ / ⁇ or less.
  • a color filter 111 is provided in each of the plurality of pixel portions.
  • the partition wall 112 provided between the color filters 111 adjacent to each other among the plurality of pixel portions functions as a condensing unit for condensing light incident on the pixel portion on the photoelectric conversion layer of the pixel portion.
  • any of the first to third color filters may be formed outside the effective pixel area, the process of forming only the light shielding layer 113 can be omitted, and the manufacturing cost can be suppressed.
  • the partition formation process can be performed either after the light shielding layer formation process, after the first color color filter formation process, after the second color color filter formation process, or after the third color color filter formation process, and the manufacturing technology to be used, manufacture It can be selected as appropriate depending on the combination of methods.
  • the protective film 110 is the same as that described for the protective film 10 of the photoelectric conversion element, and the internal stress is -600 MPa or more and less than -200 MPa, preferably -400 MPa or more and less than -200 MPa. And the product of which is ⁇ 40,000 MPa ⁇ nm or more and ⁇ 14,000 MPa ⁇ nm or less. Details are as described in the section of the photoelectric conversion element.
  • the imaging devices of the example and the comparative example were manufactured by the following procedure.
  • the imaging device of each example has the same configuration except that the configuration of the protective film, the height of the end of the pixel electrode, and the angle are different from each other.
  • the readout circuit 116, the wiring layer including the connection portion 105, the insulating layer 102, and the pixel electrode 104 were manufactured on the substrate 101 by a standard CMOS image sensor process.
  • the pixel electrode size was 3 ⁇ m (3 ⁇ m ⁇ 3 ⁇ m square).
  • the taper angle of the pixel of each example and comparative example and the height of the step (the thickness of the pixel electrode) will be described later.
  • the pressure in the chamber was reduced to 1 ⁇ 10 ⁇ 4 Pa or less.
  • An electron blocking layer was deposited on the pixel electrode to a thickness of 100 nm at a deposition rate of 10 to 12 nm / s by a resistance heating deposition method while rotating the holder for holding the substrate.
  • the material represented by the chemical formula 1 (fullerene C 60 ) and the material represented by the chemical formula 2 are used at deposition rates of 16 to 18 nm / s and 25 to 28 nm / s, respectively, and the volume ratio of chemical formula 1 to chemical formula 2 is 1: 3. It co-evaporated so that it might become and the photoelectric converting layer was formed.
  • the thickness was 400 nm. After that, it was transported to a sputtering chamber, and an ITO film as a counter electrode was formed to a thickness of 10 nm on the photoelectric conversion layer by RF magnetron sputtering.
  • the configuration and film thickness of the sealing film of each of the example and the comparative example are shown in Table 1.
  • the AlOx film was formed using trimethylaluminum and water by an atomic deposition method.
  • AlOx was deposited under the condition of an internal stress of 450 MPa.
  • the silicon oxynitride film (hereinafter sometimes referred to as a SiON film) was formed by introducing SiH 4 , NH 3 , N 2 O, N 2 as a reaction gas using a plasma CVD method. .
  • the film forming temperature was 180 ° C.
  • the film forming pressure was 110 Pa
  • the internal stress was adjusted by changing the film forming power from 100 to 475 W.
  • the protective films of Examples 1 to 10 and Comparative Examples 1 to 5 are respectively formed of a laminated film of an AlOx film and a silicon oxynitride film in Examples 11 and 12 and Comparative Example 6 only.
  • the imaging element was manufactured in the above procedure.
  • the film stress is measured by thin film stress measurement using FLA-2320 manufactured by KLA-Tencor, that is, the method of measuring the change of the curvature radius of the substrate before and after thin film deposition by a laser scan under room temperature in the air. It measured by.
  • films are formed on a silicon substrate, and films are formed under the same film forming conditions as the thin film having a stress measured by the film stress measurement method.
  • Table 1 summarizes the configuration conditions of each Example and Comparative Example, and the evaluation results.
  • Example 1 has the same stress as Comparative Example 2, the steps of the pixel electrode and the taper angles are within the scope of the present invention. From these examples, it is clear that the generation of wrinkles can be suppressed if the step of the pixel electrode satisfies the conditions of 3 nm or more and the taper angle of 10 ° or more even if the stress is less than -200 MPa.
  • Comparative Example 4 was not suitable for practical use because the step of the pixel electrode exceeded 100 nm and the dark current became large.
  • the stress ⁇ film thickness of the protective film was smaller than ⁇ 40,000 MPa ⁇ nm (large as an absolute value), and wrinkles after heating occurred.
  • Examples 11 and 12 when the protective film is formed of a plurality of layers, a satisfactory protective film can be obtained if the range of the present invention is satisfied.
  • FIG. 5 shows an area after the pixel electrode has a step, and after forming an organic layer consisting of an electron block layer and a photoelectric conversion layer, a transparent electrode and a protective film (internal stress-350 MPa) on a flat substrate area without a pixel electrode.
  • the area 22 where the pixel electrode is formed and the area where the white wavy wrinkles are otherwise generated is an area where the pixel electrode is not formed, that is, a flat substrate.
  • the stress of the protective film is large, it is clear that the effect obtained by providing an electrode having a level difference with the substrate surface is remarkable.

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10756132B2 (en) 2016-03-29 2020-08-25 Sony Corporation Solid-state imaging device, method of manufacturing the same, and electronic apparatus

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5835450B2 (ja) 2013-11-27 2015-12-24 株式会社デンソー 回転機の制御装置
CN106326616B (zh) 2015-06-25 2019-01-15 华邦电子股份有限公司 电子构件的应力估算方法
TWI625634B (zh) * 2015-06-25 2018-06-01 華邦電子股份有限公司 電子構件的應力估算方法
JP2017168806A (ja) * 2015-12-21 2017-09-21 ソニー株式会社 撮像素子、固体撮像装置及び電子デバイス
US11751426B2 (en) * 2016-10-18 2023-09-05 Universal Display Corporation Hybrid thin film permeation barrier and method of making the same
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011228648A (ja) * 2010-03-31 2011-11-10 Fujifilm Corp 撮像素子
JP2013055117A (ja) * 2011-09-01 2013-03-21 Fujifilm Corp 光電変換素子の製造方法、および撮像素子の製造方法
WO2013065665A1 (ja) * 2011-10-31 2013-05-10 富士フイルム株式会社 撮像素子
JP2013098322A (ja) * 2011-10-31 2013-05-20 Fujifilm Corp 光電変換素子およびその製造方法、ならびに撮像素子およびその製造方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011228648A (ja) * 2010-03-31 2011-11-10 Fujifilm Corp 撮像素子
JP2013055117A (ja) * 2011-09-01 2013-03-21 Fujifilm Corp 光電変換素子の製造方法、および撮像素子の製造方法
WO2013065665A1 (ja) * 2011-10-31 2013-05-10 富士フイルム株式会社 撮像素子
JP2013098322A (ja) * 2011-10-31 2013-05-20 Fujifilm Corp 光電変換素子およびその製造方法、ならびに撮像素子およびその製造方法

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10756132B2 (en) 2016-03-29 2020-08-25 Sony Corporation Solid-state imaging device, method of manufacturing the same, and electronic apparatus
US12015040B2 (en) 2016-03-29 2024-06-18 Sony Corporation Solid-state imaging device, method of manufacturing the same, and electronic apparatus capable to protect a photoelectric conversion film

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