TRANSPARENT CONDUCTOR AND ORGANIC DEVICE

Abstract

A transparent conductor (10), consisting of: A transparent substrate (11); a first metal oxide layer (12); a metal layer (18) containing a silver alloy; a third metal oxide layer (14); and a second metal oxide layer (16), in the order mentioned, wherein the first metal oxide layer (12) consists of a metal oxide which differs from ITO, the second metal oxide layer (16) contains ITO, the third metal oxide layer (14) consists of a metal oxide which differs from ITO and which contains zinc oxide, indium oxide, titanium oxide and tin oxide, a work function of a surface (16a) of the second metal oxide layer (16) relative to a metal layer side is 4.5 eV or more and the second metal oxide layer (16) and the third metal oxide layer (14) are in direct contact with each other.

Description

Technical area

[0001] The present disclosure relates to a transparent conductor and an organic component. State of the art

[0002] Transparent conductors, which combine transparency and conductivity, are used in various applications. Organic devices, including organic electroluminescent (EL) displays, organic EL lighting, and organic thin-film solar cells, have been implemented in practice in recent years. Organic EL displays and organic EL lighting, for example, consist of a transparent electrode layer (anode), an organic layer, and a reflective electrode layer (cathode) laminated onto a transparent substrate of glass or similar material. When a voltage is applied between the transparent electrode layer and the reflective electrode layer, a current flows between the electrodes, and the organic layer emits light. The light generated in the organic layer passes through the electrodes and is conducted to the outside.For this reason, a transparent electrode is used for at least one of the electrodes.

[0003] Disclosure 1 discloses the provision of a laminate structure with a sandwich construction. This structure consists of a thin metal film layer made of a silver alloy, sandwiched between a pair of transparent refractive index thin films made of a transparent base material such as glass or similar. For example, indium tin oxide (ITO) is used as the material for the transparent refractive index thin films.

[0004] Disclosure 2 discloses that a high-function-of-electron-emitter anode is used as the anode of an organic electroluminescent element to efficiently introduce impurities and to improve electron injection efficiency by providing a layer of a transparent electrode material with a high-function-of-electron-emitter material such as ITO. Disclosure 3 introduces a substrate for an organic light-emitting device. The substrate comprises several layers, including an antireflective sublayer with a given optical thickness L1; a first metallic layer; a first separating layer with a given optical thickness L2; ​​a second metallic layer with intrinsic electrical conductivity; and a top layer for adjusting the function of electronegativity. Disclosure Note 4 relates to a transparent conductor. This transparent conductor contains, in that order, a transparent resin base, a first metal oxide layer, a metal layer containing a silver alloy, and a second metal oxide layer. Disclosure 5 relates to a transparent electrode with a laminated structure consisting of a transparent thin film layer (a) with a high refractive index and a metal thin film layer (b) on a transparent shaped polymer substrate (A). Citation list - Patent literature Publication 1: Japanese unexamined patent publication no. JP 2002-015623A Publication 2: Japanese unexamined patent publication no. JP 2006-324 016 A Disclosure Document 3: US 2011 / 0037379A1 Disclosure document 4: WO 2017 / 099187A1 Disclosure document 5: JP 2009-147364A Summary of the invention: Technical problem

[0005] An organic layer is laminated onto transparent conductors for organic devices. Such a transparent conductor must have a higher conductivity. Furthermore, smooth migration of impurities between the transparent conductor and the organic layer must be achieved to increase the light-gathering efficiency of the organic layer. For example, if the organic device is an organic electroluminescent (EL) cell, it is necessary to efficiently introduce impurities from the transparent conductor into the organic layer. Conversely, if the organic device is an organic thin-film solar cell, the transparent conductor must efficiently absorb impurities from the organic layer. Increasing the work function of the transparent conductor onto which the organic layer is laminated thus promotes smooth migration of impurities between the transparent conductor and the organic layer.

[0006] While conventional organic devices are generally rigid, using glass or similar materials as substrates, flexible organic devices are increasingly in demand. When ITO (indium tin oxide) is used as the electrode material, increased conductivity is required to improve the light-gathering efficiency of the organic device. To enhance conductivity when using ITO, a large ITO thickness is typically desired. However, excessive ITO thickness can lead to flexural cracking and subsequent failure of the junction.Furthermore, such a transparent conductor, in which an ITO layer and a conductive layer containing a silver alloy are in direct contact with each other, gives cause for concern that corrosion of the metal layer will progress and that transparency and conductivity will deteriorate during long-term use in a high-temperature / high-humidity environment.

[0007] Under such circumstances, one aspect of the present disclosure is the provision of a transparent conductor that is improved in terms of conductivity, flexibility, and corrosion resistance, and that enables the formation of organic devices with enhanced performance. Another objective of the present disclosure is to provide an organic device that has improved performance and is also advantageous in terms of flexibility and corrosion resistance through the inclusion of the transparent conductor.

[0008] Another aspect of this disclosure is the provision of a transparent conductor that exhibits improved conductivity and high work function. Yet another aspect is the provision of an organic device that, due to the incorporation of the transparent conductor described above, offers improved performance. Solution to the problem

[0009] The present disclosure provides in one aspect a transparent conductor comprising: a transparent substrate; a first metal oxide layer; a metal layer containing a silver alloy; and a second metal oxide layer, in the aforementioned order, wherein the first metal oxide layer consists of a metal oxide other than ITO, the second metal oxide layer contains ITO, and the work function of the surface of the second metal oxide layer relative to the metal layer side is 4.5 eV or more.

[0010] The transparent conductor can achieve high conductivity even at low thicknesses by incorporating a metal layer containing a silver alloy. Since the first metal oxide layer consists of a metal oxide different from ITO, corrosion of the metal layer caused by direct contact between the ITO and the metal layer is prevented. In this way, a transparent conductor with excellent corrosion resistance and conductivity can be achieved. Consequently, the transparent conductor offers improved conductivity, flexibility, and corrosion resistance.

[0011] Furthermore, the work function of the surface of the second metal oxide layer relative to the metal layer side is 4.5 eV or higher. This allows impurities to migrate efficiently between the transparent conductor and the organic layer, thus improving the performance of the organic device when an organic layer is deposited on top of the second metal oxide layer to form an organic device. For example, if the organic device is an organic EL element, impurities can be efficiently introduced from the second metal oxide layer of the transparent conductor into the organic layer. Conversely, if the organic device is an organic thin-film solar cell, impurities can be efficiently extracted from the organic layer into the second metal oxide layer of the transparent conductor.

[0012] The transparent conductor includes a third metal oxide layer between the metal layer and the second metal oxide layer. This third metal oxide layer consists of a metal oxide other than ITO and contains zinc oxide, indium oxide, titanium oxide, and tin oxide. This third metal oxide layer, deposited on top of the metal layer, exhibits good conductivity. The metal layer, which contains a silver alloy, is surrounded by a pair of metal oxide layers, each consisting of a metal oxide other than ITO: the first metal oxide layer and the third metal oxide layer. Therefore, the metal layer and the second ITO-containing metal oxide layer are not in direct contact with each other.Accordingly, corrosion of the metal layer caused by direct contact between the silver-alloyed metal layer and ITO can be sufficiently prevented.

[0013] It is preferable that the first metal oxide layer contains zinc oxide, indium oxide, and titanium oxide. This further prevents corrosion of the metal layer.

[0014] It is preferable that the carrier density of the second metal oxide layer be 3.5 10 20 × [cm -3 ] or less. This allows the work function of the surface of the second metal oxide layer to be increased relative to the metal layer side. Accordingly, this allows defects to migrate smoothly between the transparent conductor (transparent electrode) and the organic layer when an organic layer is deposited on top of the second metal oxide layer to form an organic device.

[0015] The present disclosure provides, in a further aspect, a transparent conductor comprising: a transparent substrate; a first metal oxide layer; a metal layer containing a silver alloy; and a second metal oxide layer, in the aforementioned order, wherein the second metal oxide layer contains ITO and the ratio of peak area B in a binding energy range of 0.5 to 2.3 eV to peak area A in a binding energy range of 14 to 21 eV (B / A) in an X-ray photoelectron spectrum for the surface of the second metal oxide layer is 1.0 × 10 -3 or less.

[0016] The transparent conductor has improved conductivity because it incorporates a silver alloy metal layer between the first and second metal oxide layers. Furthermore, the transparent conductor exhibits a high work function, as the ratio of peak area B in a binding energy range of 0.5 to 2.3 eV to peak area A in a binding energy range of 14 to 21 eV (B / A) is 1.0 × 10⁻⁶. -3 or less. Although the reason for the increase in exit labor with a decreasing ratio (B / A) is not entirely clear, it is explained as follows.

[0017] The work function is the energy required to extract an electron from a surface to infinity. X-ray photoelectron spectroscopy (XPS) is a method for measuring the kinetic energy of photoelectrons emitted from a surface when irradiated with X-rays. Of the binding energies measured in X-ray photoelectron spectroscopy, a peak intensity in the range of 0.5 to 2.3 eV is considered to indicate the electron density (distribution or probability) in the upper part of a valence band in an energy band diagram. It is expected that when this peak intensity, i.e., the peak area B, is smaller, the electron density near the surface is lower.In this case, the electron density in the upper part of the valence band is low, and it follows that electrons are present at a lower energy level, thus requiring more energy to extract an electron. This, in turn, leads to a higher work function from a surface. The transparent conductor, including the second metal oxide layer with its high work function, allows for the smooth migration of impurities when an organic layer is laminated onto it.

[0018] The reason for specifying not the value of the peak area B, but rather the ratio of peak area B to peak area A in a binding energy range of 14 to 21 eV (B / A), is as follows. In short, it is desirable to reduce the variation between measuring instruments and conditions and to increase the work function with higher precision. The peak area A in a binding energy range of 14 to 21 eV depends on the peak intensity of indium [In4d], which is the primary component in the ITO. Therefore, the variation between measuring instruments, conditions, etc., can be sufficiently reduced by specifying it as a ratio to the peak area A.

[0019] The transparent conductor has a third metal oxide layer between the metal layer and the second metal oxide layer. In other words, the transparent conductor contains a transparent substrate, a first metal oxide layer, a metal layer with a silver alloy, a third metal oxide layer, and a second metal oxide layer in that order. Furthermore, a water vapor barrier layer, a metal oxide layer with a different composition than the first metal oxide layer, or a metal nitride layer may be present between the transparent substrate and the first metal oxide layer.

[0020] It is preferable that the first metal oxide layer consists of and contains a metal oxide different from ITO. The third metal oxide layer consists of a metal oxide different from ITO and contains zinc oxide, indium oxide, and titanium oxide.

[0021] The metal layer containing a silver alloy is surrounded by two metal oxide layers, each consisting of a different metal oxide than ITO (i.e., the first and third metal oxide layers). The metal layer and the second metal oxide layer containing ITO are not in direct contact with each other. Therefore, corrosion of the metal layer caused by direct contact between the silver-alloyed metal layer and ITO is effectively prevented. The first metal oxide layer further prevents corrosion due to the inclusion of zinc oxide, indium oxide, and titanium oxide. Furthermore, the third metal oxide layer, containing zinc oxide, indium oxide, titanium oxide, and tin oxide, has enhanced conductivity, thus further increasing the overall conductivity.

[0022] It is preferable that the work function of the surface of the second metal oxide layer relative to the third metal oxide layer is 4.5 eV or higher. This allows for smoother impurity migration when an organic layer is laminated. For example, if the organic device is an organic electroluminescent (EL) cell, impurities can be efficiently introduced from the second metal oxide layer of the transparent conductor into the organic layer. Conversely, if the organic device is an organic thin-film solar cell, impurities can be extracted from the organic layer into the second metal oxide layer of the transparent conductor.

[0023] It is preferable for the thickness of the second metal oxide layer to be 2 nm or more. This allows the work function of the surface of the second metal oxide layer to be stably increased relative to the metal layer side. This, in turn, facilitates the migration of defects between the transparent conductor (transparent electrode) and an organic layer.

[0024] It is preferable that the surface resistance of the transparent conductor be 30 Ω / m² (ohms per square meter) or lower. This low resistance makes the transparent conductor suitable for various applications. For example, when used in an organic device, it can improve the device's performance.

[0025] The present disclosure provides, in a further aspect, an organic device comprising the transparent conductor described above. The surface of the second metal oxide layer of the transparent conductor described above has a high work function. Accordingly, the migration of impurities across the organic layer in the organic device can be facilitated. The transparent conductor described above exhibits improved conductivity, flexibility, and corrosion resistance. The organic device, including such a transparent conductor, offers improved performance and is simultaneously enhanced in terms of flexibility and corrosion resistance. Advantageous properties of the invention

[0026] The present disclosure may, in one aspect, provide a transparent conductor that is improved in terms of conductivity, flexibility, and corrosion resistance, and enables the formation of organic devices with enhanced performance. In another aspect, the present disclosure may provide an organic device that exhibits improved performance and is enhanced in terms of flexibility and corrosion resistance through the inclusion of the transparent conductor described above.

[0027] The present disclosure may, in a further aspect, provide a transparent conductor that has improved conductivity and simultaneously exhibits high work function. The present disclosure may, in a further aspect, provide an organic device that exhibits improved performance through the inclusion of the transparent conductor described above. Brief description of the drawings [ Fig. 1] Fig. Figure 1 shows a cross-sectional view that schematically illustrates a first embodiment of the transparent conductor. [ Fig. 2] Fig. Figure 2 shows a cross-sectional view that schematically illustrates a second embodiment of the transparent conductor. [ Fig. 3] Fig. Figure 3 shows a cross-sectional view that schematically illustrates a third embodiment of the transparent conductor. [ Fig. 4] Fig. Figure 4 shows a diagram that schematically represents one embodiment of the organic component. [ Fig. 5] Fig. Figure 5 shows a diagram illustrating the elemental properties of the organic building block. [ Fig. 6] Fig. Figure 6 shows a diagram illustrating an example of the relationship between carrier density and output function. [ Fig. 7] Fig.Figure 7(A) shows X-ray photoelectron spectra including a binding energy range of 0.5 to 2.3 eV for the surface (before Ar ion etching) of the second metal oxide layer in Example 11, Example 12 and Comparative Example 5; and Fig. Figure 7(B) shows X-ray photoelectron spectra including a binding energy range of 0.5 to 2.3 eV for the inside (exposed surface after Ar ion etching) of the second metal oxide layer in Example 11, Example 12 and Comparative Example 5. [ Fig. 8] Fig. Figure 8 shows an enlarged view of the X-ray photoelectron spectra with a binding energy range of 0.5 to 2.3 eV for the surface (before Ar ion etching) of the second metal oxide layer in Example 11 and Comparative Example 5. [ Fig. 9] Fig.Figure 9 shows an enlarged view of the X-ray photoelectron spectra with a binding energy range of 0.5 to 2.3 eV for the surface (before Ar ion etching) of the second metal oxide layer in Example 12 and Comparative Example 5. [ Fig. 10] Fig. Figure 10(A) shows X-ray photoelectron spectra with a binding energy range of 14 to 21 eV for the surface (before Ar ion etching) of the second metal oxide layer in Example 11, Example 12 and Comparative Example 5; and Fig. Figure 10(B) shows X-ray photoelectron spectra with a binding energy range of 14 to 21 eV for the inside (exposed surface after Ar ion etching) of the second metal oxide layer in Example 11, Example 12 and Comparative Example 5. [ Fig. 11] Fig.Figure 11 shows X-ray photoelectron spectra in a binding energy range of about 276 to 293 eV for the surface (before Ar ion etching) of the second metal oxide layer in Example 11, Example 12 and Comparative Example 5. Description of the embodiments

[0028] Some embodiments of this disclosure are described in detail below with reference to the drawings. However, the embodiments described below are examples to illustrate this disclosure and are not intended to limit it to the following content. The descriptions use the same reference numeral for identical structures or components with identical functions, and redundant descriptions are occasionally omitted. The positional relationship, such as top and bottom / left and right in a drawing, is as shown in the drawing unless otherwise specified. Furthermore, the size ratio of each layer is not limited to that shown. <Transparenter Leiter> [First embodiment]

[0029] Fig.Figure 1 shows a cross-sectional view schematically illustrating an embodiment of the transparent conductor. The transparent conductor 10 has a laminate structure in which a transparent substrate 11, a first metal oxide layer 12, a metal layer 18, a third metal oxide layer 14, and a second metal oxide layer 16 are arranged in the sequence shown.

[0030] The term "transparent" in this specification means that visible light is transmitted and a certain degree of light scattering is permissible. The degree of light scattering required for the transparent conductor 10 depends on its application. A "semi-transparent" conductor, in which light scattering is permitted, is also included in the term "transparent" in this specification. It is desirable for the degree of light scattering to be lower and the transparency higher. For example, the total light transmittance of the transparent conductor 10 is 82% or more, preferably 85% or more, and more preferably 88% or more. The total light transmittance is the transmittance for light including diffusely transmitted light, determined using an integrating sphere and measured with a commercially available turbidity meter.

[0031] The transparent substrate 11 is not limited and can be any flexible, transparent resin substrate. The transparent resin substrate can be an organic resin film, an organic resin sheet, or the like. Examples of the transparent substrate 11 include polyester films such as polyethylene terephthalate (PET) films and polyethylene naphthalate (PEN) films, polyolefin films such as polyethylene and polypropylene films, polycarbonate films, acrylic films, norbornene films, polyarylate films, polyethersulfone films, diacetylcellulose films, polyimide films, and triacetylcellulose films. Among these, polyester films such as polyethylene terephthalate (PET) films and polyethylene naphthalate (PEN) films are preferred.

[0032] The thickness of the transparent substrate 11 is, for example, 200 µm or less to further increase the flexibility of the transparent conductor 10. The refractive index of the transparent substrate is, for example, 1.50 to 1.70 to give the transparent conductor 10 better optical properties. The refractive index in this specification is a value measured under conditions of λ = 633 nm and a temperature of 20°C. The transparent substrate 11 may have undergone at least one surface treatment selected from the group consisting of corona discharge treatment, glow discharge treatment, flame treatment, ultraviolet irradiation treatment, electron beam irradiation treatment, and ozone treatment.

[0033] Since the transparent substrate 11 is a transparent resin substrate, the transparent conductor 10 can be given improved flexibility. This makes the transparent conductor 10 suitable as a transparent conductor for flexible organic components.

[0034] The first metal oxide layer 12 is a transparent layer containing a metal oxide. This first metal oxide layer 12 serves to protect the metal layer 18. The first metal oxide layer 12 consists of a metal oxide that is different from ITO (indium tin oxide). The composition of the first metal oxide layer 12 is not limited, except that it is free of ITO. Because the first metal oxide layer 12 is free of ITO, corrosion of the silver alloy contained in the metal layer 18 can be prevented.

[0035] To achieve both transparency and corrosion resistance at an even higher level, the first metal oxide layer can contain three components of zinc oxide, indium oxide and titanium oxide as primary components and be composed of the three components and unavoidable impurities.

[0036] The zinc oxide contained in the first metal oxide layer 12 is, for example, ZnO, and the indium oxide is, for example, In₂O₃. The titanium oxide is, for example, TiO₂. The ratio of metal atoms to oxygen atoms in each metal oxide may deviate from the stoichiometric ratio. Another oxide with a different oxidation state may be present. Although the first metal oxide layer 12 may contain tin oxide, to reduce corrosion of the silver alloy contained in the metal layer 18, it is preferable that the tin oxide (SnO₂) content be lower. It is preferable that tin oxide not be present. It is further preferable that the total content of the three components in the first metal oxide layer 12 be at least 90% by mass, and it is most preferable that the total content of the three components in the first metal oxide layer 12 be at least 95% by mass if the components are in the form of ZnO, In₂O₃, and TiO₂.

[0037] The thickness of the first metal oxide layer 12 is, for example, 60 nm or less to further increase transparency. To further improve corrosion resistance and simultaneously increase productivity, the thickness can, on the other hand, be, for example, 5 nm or greater, or 20 nm or greater.

[0038] If the zinc oxide, indium oxide, and titanium oxide in the first metal oxide layer 12 are present in the form of ZnO, In₂O₃, and TiO₂, it is preferable that the ZnO content be 20 to 85 mol% relative to the sum of ZnO, In₂O₃, and TiO₂, and it is even more preferable that the ZnO content be 30 to 80 mol% relative to the sum of ZnO, In₂O₃, and TiO₂. In the same case, to improve transparency and achieve both high conductivity and high corrosion resistance, it is preferable that the In₂O₃ content be 10 to 35 mol% relative to the sum of ZnO, In₂O₃, and TiO₂, and it is further preferable that the In₂O₃ content be 10 to 25 mol% relative to the sum of ZnO, In₂O₃, and TiO₂.

[0039] In order to achieve high transparency and improved corrosion resistance in combination during the same conversion, it is preferable that the TiO2 content be 5 to 15 mol% compared to the sum of ZnO, In2O3 and TiO2, and it is further preferable that the TiO2 content be 7 to 13 mol% compared to the sum of ZnO, In2O3 and TiO2.

[0040] The first metal oxide layer 12 can have low conductivity and act as an insulator. In this case, the conductivity of the transparent conductor 10 can be compensated for by the metal layer 18 and the third metal oxide layer 14. The first metal oxide layer 12 can be formed using any vacuum layer formation method, including vacuum deposition, sputtering, ion deposition, and CVD processes. Among these, sputtering is preferable because it allows for the use of a smaller film formation chamber and offers a high film formation rate. Examples of sputtering methods include DC magnetron sputtering. The target can be either a metal or a metal oxide target. The first metal oxide layer 12 can be a layer that does not dissolve in acidic etching solution.A water vapor barrier layer, a metal oxide layer with a different composition than the first metal oxide layer, or a metal nitride layer can be enclosed between the transparent substrate 11 and the first metal oxide layer 12.

[0041] It is preferable that the metal layer 18 contains a silver alloy as its primary component. The metal layer 18 can be a layer that dissolves in acidic etching solution. This allows for easy patterning. The metal layer 18, with its high transparency and high conductivity, can sufficiently reduce the surface resistance of the transparent conductor 10 while maintaining a sufficiently high transmittance of visible light through the transparent conductor 10. The components of the silver alloy are, for example, Ag and at least one element from the group consisting of Pd, Cu, Nd, In, Sn, and Sb. Examples of silver alloys are Ag-Pd, Ag-Cu, Ag-Pd-Cu, Ag-Nd-Cu, Ag-In-Sn, and Ag-Sn-Sb. It is preferable that the silver alloy contains Ag as its primary component and the aforementioned metals as secondary components. The metal layer 18 can also be a layer consisting solely of metal.

[0042] The content of metals other than silver in the silver alloy is, for example, 0.5 to 5% by mass to further improve corrosion resistance and transparency. It is preferable for the silver alloy to contain phosphorus (Pd) as an additional metal. This further enhances corrosion resistance in high-temperature / high-humidity environments.

[0043] The thickness of the metal layer 18 can be, for example, 5 to 25 nm. If the thickness of the metal layer 18 is too small, the continuity of the metal layer 18 will be impaired, and the surface resistance of the transparent conductor 10 will likely be higher. Conversely, if the thickness of the metal layer 18 is too large, the sufficiently high transparency will likely be compromised.

[0044] The metal layer 18 serves to adjust the conductivity and surface resistance of the transparent conductor 10. The metal layer 18 can be formed using any vacuum layer formation method, including vacuum deposition, sputtering, ion deposition, and CVD processes. Sputtering is preferable because it allows for the use of a smaller film formation chamber and a high film formation rate. Examples of sputtering methods include DC magnetron sputtering. A metal target can be used.

[0045] The third metal oxide layer 14 is a transparent layer containing a metal oxide. The function of the third metal oxide layer 14 is to protect the metal layer 18 and to regulate conductivity. The third metal oxide layer 14 consists of a metal oxide that differs from ITO. It is preferable that the third metal oxide layer 14 and the first metal oxide layer 12 have different compositions.

[0046] The third metal oxide layer 14 need not contain ITO as a primary component to sufficiently prevent corrosion of the metal layer 18. To improve conductivity, the third metal oxide layer 14 may contain four components: zinc oxide, indium oxide, titanium oxide, and tin oxide. The third metal oxide layer 14 may contain these four components as primary components to maintain sufficiently high conductivity while preventing corrosion of the silver alloy contained in the metal layer 18. It may consist of these four components and unavoidable impurities originating from impurities or similar substances present in the oxide raw materials.It is preferable that the total content of the four components in the third metal oxide layer be 14 90% by mass or more, and it is further preferable that the total content of the four components in the third metal oxide layer be 14 95% by mass or more if the components are ZnO, In2O3, TiO2 and SnO2.

[0047] Zinc oxide is ZnO, for example, and indium oxide is In₂O₃. Titanium oxide is TiO₂, for example, and tin oxide is SnO₂. The ratio of metal atoms to oxygen atoms in each metal oxide can deviate from the stoichiometric ratio. Another oxide with a different oxidation state may also be present.

[0048] Since the zinc oxide, indium oxide, titanium oxide, and tin oxide in the third metal oxide layer 14 are present in the form of ZnO, In₂O₃, TiO₂, and SnO₂, it is preferable that the ZnO content be up to 60 mol% relative to the sum of ZnO, In₂O₃, TiO₂, and SnO₂ 20, and further preferable that the ZnO content be up to 50 mol% relative to the sum of ZnO, In₂O₃, TiO₂, and SnO₂ 25. To achieve even higher levels of transparency, conductivity, and corrosion resistance with the same components, it is preferable that the In₂O₃ content be up to 40 mol% relative to the sum of ZnO, In₂O₃, TiO₂, and SnO₂ 10. It is even better if the In2O3 content is 15 to 35 mol% compared to the sum of ZnO, In2O3, TiO2 and SnO2.

[0049] For identical components, to achieve high transparency and improved corrosion resistance, it is preferable that the TiO2 content be 5 to 30 mol% relative to the sum of ZnO, In2O3, TiO2, and SnO2, and that the TiO2 content be 10 to 20 mol% relative to the sum of ZnO, In2O3, TiO2, and SnO2. For the same conversion, to further improve conductivity, it is preferable that the SnO2 content be 5 to 40 mol% relative to the sum of ZnO, In2O3, TiO2, and SnO2, and even better that the SnO2 content be 10 to 30 mol% relative to the sum of ZnO, In2O3, TiO2, and SnO2.

[0050] The thickness of the third metal oxide layer 14 is, for example, 60 nm or less, in order to reduce the surface resistance of the transparent conductor 10 while simultaneously increasing its transparency. To further improve the corrosion resistance of the transparent conductor 10 and simultaneously increase productivity, the thickness is, for example, 5 nm or greater.

[0051] The second metal oxide layer 16 is a transparent layer containing a metal oxide. When the second metal oxide layer 16 is positioned, for example, adjacent to an organic layer of an organic device, it facilitates the migration of defects. The second metal oxide layer 16 consists of an ITO-containing metal oxide. The second metal oxide layer 16 may contain ITO as a primary component and may consist of ITO and unavoidable impurities originating from impurities present in the raw material or similar sources. It is preferable that the ITO content in the second metal oxide layer 16 be 90% by mass or more, and it is further preferable that the ITO content in the second metal oxide layer 16 be 95% by mass or more.

[0052] ITO is an oxide of indium and tin. This oxide is a mixed oxide containing In, Sn, and O (oxygen) as its constituent elements. The second metal oxide layer 16 may contain another composite oxide.

[0053] The work function of surface 16a of the second metal oxide layer 16 with respect to the third side of the metal oxide layer 14 (side of the metal layer 18) is 4.5 eV or higher, preferably 4.7 eV or higher, more preferably 5.0 eV or higher, and even more preferably 5.1 eV or higher. If an organic layer for the fabrication of an organic device has such a high work function on surface 16a of the second metal oxide layer 16, the introduction of impurities into or the removal of impurities from the organic layer can be carried out in a sufficiently simple manner. Accordingly, the performance of the organic device can be improved. The work function of surface 16a of the second metal oxide layer 16 can be measured with any commercially available measuring instrument.

[0054] To increase the work function of the surface of a transparent electrode, surface treatments such as UV ozone treatment and plasma treatment are performed. In this case, an additional surface treatment step is required. On the other hand, the second metal oxide layer 16 of the present embodiment already has a high work function without surface treatment, which has the advantage that a surface treatment is not necessary. However, further improvement of the work function through surface treatment is not excluded.

[0055] The work function of surface 16a of the second metal oxide layer 16 tends to depend on the composition near surface 16a. For example, the work function of surface 16a can be adjusted by changing the ratio of oxygen atoms in ITO. In particular, if the second metal oxide layer 16 is formed by direct current magnetron sputtering with a target consisting of an ITO sintered body, the work function of surface 16a of the second metal oxide layer 16 can be adjusted by changing the ratio of oxygen gas to inert gas during sputtering.

[0056] When a mixed gas of inert gas and oxygen gas is used as the gas for sputtering, the work function of the surface 16a of the second metal oxide layer 16 tends to increase with increasing flow rate ratio of oxygen gas to inert gas.

[0057] The support density of the second metal oxide layer 16 is preferably 3.5 × 10 20 [cm -3 ] or less, and even more preferably 2.5 × 10 20 [cm -3 If an organic layer with such a low support density is provided on the second metal oxide layer 16 for the fabrication of an organic device, the introduction of defects into the organic layer or the uptake of defects from the organic layer can be carried out in a sufficiently simple manner. The support density of the second metal oxide layer 16 in the transparent conductor 10 can be determined by separately fabricating a sample of a monolayer with the same composition and structure as the second metal oxide layer 16 in the transparent conductor 10 and measuring the support density of the sample with a commercially available measuring instrument.

[0058] The surface resistance of surface 16a of the second metal oxide layer 16 in the transparent conductor 10 is preferably 30 Ω / m² or less, and more preferably 25 Ω / m² or less. The transparent conductor 10, which has such a low surface resistance, can be used for various applications. For example, when used in an organic EL cell, the luminous efficacy of the organic EL cell can be improved. When used in an organic thin-film solar cell, for example, the efficiency of the organic thin-film solar cell in generating electricity can be improved. The surface resistances in this specification are values ​​obtained by four-wire measurement.

[0059] On the other hand, the surface resistance of the second metal oxide layer 16 as a monolayer can be 200 Ω / m² or higher, and it is preferable that the surface resistance of the second metal oxide layer 16 as a monolayer be 400 Ω / m² or higher. The second metal oxide layer 16, which has such a relatively high surface resistance, tends to have a high work function. Accordingly, the transparent conductor 10 can be useful for organic devices.

[0060] The thickness of the second metal oxide layer 16 is preferably 2 nm or greater, more preferably 5 nm or greater, and even more preferably 10 nm or greater, in order to stably increase the work function of the surface 16a. To sufficiently increase the transparency and flexibility of the transparent conductor 10, the thickness of the second metal oxide layer 16 is, for example, 100 nm or less.

[0061] The thickness of each layer comprising the transparent conductor 10 can be measured using the following procedure. The transparent conductor 10 is sectioned using a focused ion beam (FIB) apparatus to obtain a cross-section. The cross-section is observed under a transmission electron microscope (TEM) to measure the thickness of each layer. It is preferable to measure at 10 or more arbitrarily selected positions to determine the average value. A microtome, an instrument other than focused ion beam apparatus, can be used to obtain a cross-section. A scanning electron microscope (SEM) can be used to measure the thickness. Alternatively, the layer thickness can be measured using an X-ray fluorescence analyzer.

[0062] The thickness of the transparent conductor 10 can be 210 µm or less, or 200 µm or less. Such a thickness can adequately meet the required level of transparency and flexibility.

[0063] The first metal oxide layer 12 and the third metal oxide layer 14 can be identical in thickness, structure, and composition, or they can differ in at least one aspect of their thickness, structure, and composition. With a configuration where the composition of the first metal oxide layer 12 and that of the third metal oxide layer 14 differs, the second metal oxide layer 16, the third metal oxide layer 14, and the metal layer 18 can be selectively removed in one step by etching with an acidic etching solution, leaving the first metal oxide layer 12 unetched.

[0064] The transparent conductor 10 with the configuration described above also exhibits improved alkali resistance. Consequently, sampling can be carried out efficiently. The transparent conductor 10 can be suitable for use in organic devices such as organic EL displays, organic EL lighting, and organic thin-film solar cells. [Modification of the first embodiment]

[0065] The present modification also has the in Fig.Figure 1 shows the laminate structure. The transparent substrate 11, the first metal oxide layer 12, the metal layer 18, and the third metal oxide layer 14 are the same as those in the first embodiment described above. The second metal oxide layer 16 in the present modification is also a transparent layer containing a metal oxide and contains ITO. When the second metal oxide layer 16 is positioned, for example, adjacent to an organic layer of an organic device, it facilitates the migration of defects. The second metal oxide layer 16 can contain ITO as the primary component and can consist of ITO and unavoidable impurities originating from impurities present in the raw material or the like. The second metal oxide layer 16 can also contain another composite oxide.It is preferable that the ITO content in the second metal oxide layer be 16 90% by mass or more, and it is further preferable that the ITO content in the second metal oxide layer be 16 95% by mass or more.

[0066] In the present modification, in an X-ray photoelectron spectrum obtained by X-ray photoelectron spectroscopy for the surface 16a of the second metal oxide layer 16 compared to the third side of the metal oxide layer 14 (side of the metal layer 18), the ratio of the peak area B in a binding energy range of 0.5 to 2.3 eV to the peak area A in a binding energy range of 14 to 21 eV (B / A) is 1.0 × 10 -3 or less. Area 16a with such a ratio (B / A) has a high work function.

[0067] The ratio of peak area B to peak area A (B / A) can be measured using the following procedure. First, X-ray photoelectron spectroscopy is performed on surface 16a using a commercially available instrument. The peak intensity is measured, for example, in intervals of 0.1 eV. The position of the carbon [C1s] peak is checked in the resulting X-ray photoelectron spectrum. Then, a shift correction is performed to adjust the X-ray photoelectron spectrum so that the binding energy of the carbon [C1s] peak is adjusted to 284.8 eV.

[0068] The mean peak intensities in a binding energy range of 0 to 0.5 eV, considered the background intensity, are subtracted from each peak intensity in a binding energy range of 0.5 to 2.3 eV (background correction). The peak area B is determined by integrating the peak intensities after the background correction.

[0069] A linear expression is determined by using the peak intensity at a binding energy of 14 eV as the starting point and that at a binding energy of 21 eV as the endpoint. The intensity determined with this linear expression is considered the background intensity. This intensity is then subtracted from each peak intensity present within the binding energy range of 14 to 21 eV (background correction). The peak area A is determined by integrating the peak intensities after the background correction.

[0070] If the background intensity is higher than the peak intensity in a region of the binding energy, and a negative value is specified when the background intensity is subtracted from the peak intensity, the peak intensity in the region of the binding energy is considered to be 0.

[0071] From the peak areas A and B determined as described above, the ratio of peak area B to peak area A (B / A) is calculated. It is deduced from the peak area B that it is related to the electron density (distribution or probability) in the upper part of a valence band in an energy band diagram. If this peak area B is smaller, the electron density near surface 16a is expected to be lower. In this case, the electron density of an upper part of the valence band is low, and it follows that electrons are present at lower energy levels, and therefore more energy is required to extract an electron. This results in a higher work function at surface 16a.The transparent conductor, including the second metal oxide layer 16, which has such a high work function, can smooth out the migration of defects when an organic layer is laminated onto the second metal oxide layer 16.

[0072] On the other hand, the peak area A, which is present in a binding energy range of 14 to 21 eV, depends on the peak intensity of the indium [In4d], which is the primary component in the ITO. Therefore, the variation between measuring instruments, measurement conditions, etc., can be sufficiently reduced to increase precision by not only expressing the peak area B as a ratio to the peak area A (B / A).

[0073] The ratio (B / A) is preferably 8 × 10 -4 or lower, and even more preferred 7 × 10 -4 or lower, to further increase the work function of surface 16a. The lower limit of the ratio (B / A) is, for example, 1 × 10 -6For improved precision, it is preferred to perform the determination of an X-ray photoelectron spectrum two or more times and to determine the average value.

[0074] It is preferable that the ratio of peak area B to peak area A inside the second metal oxide layer 16 (hereinafter referred to as the “ratio (B / A)’”) is higher than (B / A) on the surface of the second metal oxide layer 16. In particular, it is preferable that the ratio (B / A)’ be greater than 8 × 10 -4The interior mentioned here refers to a portion at or below a depth of 1.7 nm from surface 16a. Due to the high (B / A)' ratio in a portion at or below a depth of 1.7 nm from surface 16a, the work function can be increased as the position of the surface of the second metal oxide layer 16 approaches. The described second metal oxide layer 16 can smooth out the migration of defects when an organic layer is laminated onto it, while simultaneously improving the conductivity sufficiently.

[0075] To calculate the ratio (B / A), the surface 16a of the second metal oxide layer 16 is etched to expose the interior of the second metal oxide layer 16, and then the exposed surface is subjected to X-ray photoelectron spectroscopy to determine the X-ray photoelectron spectrum from which the peak areas A and B can be determined. The procedure for determining peak areas A and B from an X-ray photoelectron spectrum is the same as the procedure for determining peak areas A and B from an X-ray photoelectron spectrum for surface 16a.

[0076] The value of the oxygen-to-oxygen ratio (B / A) at surface 16a of the second metal oxide layer 16 is derived as a function of the electron density at surface 16a. The electron density can be adjusted by changing the ratio of oxygen atoms at surface 16a of the second metal oxide layer (ITO). If the second metal oxide layer 16 is formed by direct current magnetron sputtering with a target consisting, for example, of a sintered ITO body, the B / A ratio at surface 16a of the second metal oxide layer 16 can be adjusted by changing the oxygen-to-inert gas ratio during sputtering. Furthermore, the difference between the B / A ratio at surface 16a of the second metal oxide layer 16 and the B / A ratio' of the inner surface of the second metal oxide layer 16 can be increased by changing the oxygen-to-inert gas ratio during sputtering.

[0077] The surface 16a of the second metal oxide layer 16 with a ratio (B / A) of 1.0 × 10 -3 or lower has a high work function. The work function of surface 16a is preferably 4.5 eV or higher, more preferably a value above 4.7 eV, even more preferably 5.0 eV or higher, and particularly preferably 5.1 eV. If an organic layer is provided on surface 16a of the second metal oxide layer 16, which has such a high work function that it is suitable for the fabrication of an organic device, the injection of impurities into the organic layer or the absorption of impurities from the organic layer can be carried out in a sufficiently simple manner. This can improve the performance of the organic device. The work function of surface 16a of the second metal oxide layer 16 can be measured with any commercially available measuring instrument.

[0078] When a mixed gas of inert gas and oxygen gas is used as the gas for sputtering, the work function of the surface 16a of the second metal oxide layer 16 tends to increase with increasing flow rate ratio of oxygen gas to inert gas.

[0079] The surface resistance of surface 16a of the second metal oxide layer 16 in the transparent conductor 10 is preferably 30 Ω / m² or less, and more preferably 25 Ω / m² or less. The transparent conductor 10 with such low surface resistance values ​​can be suitable for various applications. For example, when used in an organic EL cell, the luminous efficacy of the organic EL cell can be improved. When used in an organic thin-film solar cell, for example, the efficiency of the organic thin-film solar cell in generating electricity can be improved. The surface resistance values ​​in this specification are values ​​obtained by four-wire measurement.

[0080] The thickness of the second metal oxide layer 16 is preferably 2 nm or greater, more preferably 5 nm or greater, and even more preferably 10 nm or greater, in order to stably increase the work function of the surface 16a. To sufficiently increase the transparency and flexibility of the transparent conductor 10, the thickness of the second metal oxide layer 16 is, for example, 100 nm or less.

[0081] The thickness of each layer comprising the transparent conductor 10 can be measured using the following procedure. The transparent conductor 10 is sectioned using a focused ion beam (FIB) apparatus to obtain a cross-section. The cross-section is observed under a transmission electron microscope (TEM) to measure the thickness of each layer. It is preferable to measure at 10 or more arbitrarily selected positions to determine the average value. A microtome, an instrument other than focused ion beam apparatus, can be used to obtain a cross-section. A scanning electron microscope (SEM) can be used to measure the thickness. Alternatively, the layer thickness can be measured using an X-ray fluorescence analyzer.

[0082] The thickness of the transparent conductor 10 can be 210 µm or less, or 200 µm or less. Such a thickness can adequately meet the required level of transparency and flexibility.

[0083] The first metal oxide layer 12 and the third metal oxide layer 14 can be identical in thickness, structure, and composition, or they can differ in at least one aspect of their thickness, structure, and composition. With a configuration where the composition of the first metal oxide layer 12 and that of the third metal oxide layer 14 differs, the second metal oxide layer 16, the third metal oxide layer 14, and the metal layer 18 can be selectively removed in one step by etching with an acidic etching solution, leaving the first metal oxide layer 12 unetched.

[0084] The transparent conductor 10 of the present modification can also be used in a suitable manner for organic components such as organic EL displays, organic EL lighting and organic thin-film solar cells. [Second embodiment]

[0085] Fig.Figure 2 shows a schematic cross-sectional view illustrating another embodiment of the transparent conductor. The transparent conductor 10A comprises: a first laminated section 21 containing a film-like transparent substrate 11, a first metal oxide layer 12, a metal layer 18, a third metal oxide layer 14, and a second metal oxide layer 16 in the specified order; and a second laminated section 22 containing a transparent substrate 11 and a first metal oxide layer 12 in the specified order. The first laminated section 21 and the second laminated section 22 are arranged such that they are oriented in the direction perpendicular to their lamination direction (left and right in the direction shown). Fig. 2) lies, lie next to each other (upwards and downwards in Fig. 2) The first laminated section 21 and the second laminated section 22 can be provided alternately in the aforementioned vertical direction.

[0086] The first laminated section 21 is a conductive section, formed, for example, by a structuring process. The second laminated section 22 is a non-conductive insulating section, formed, for example, by a structuring process. The transparent conductor 10A can be produced by structuring the transparent conductor 10 in Fig. 1. An example of this production method is described below.

[0087] A photoresist is applied to the surface of the second metal oxide layer 16 in the transparent conductor 10 in Fig.1. A resist film is applied and heated to form a resist film. The resist film is irradiated with ultraviolet radiation via a photomask with a predetermined pattern to expose a portion of the resist film. Subsequently, the exposed portion is removed by dissolving with a developer solution to expose a section of the surface of the second metal oxide layer 16 (positive).

[0088] The section of the second metal oxide layer 16 and the third metal oxide layer 14, as well as the metal layer 18 beneath the section, are removed by dissolution with an acidic etching solution. The first metal oxide layer 12 beneath the metal layer 18 may remain if the first metal oxide layer 12 has a composition that does not permit dissolution in acidic etching solutions.

[0089] After the second metal oxide layer 16, the third metal oxide layer 14, and the metal layer 18 have been dissolved to form the second laminated section 22, the resist film is removed. This allows the transparent conductor 10A to be obtained. Although an example of the above procedure using a positive photoresist has been described, the procedure is not limited to this, and a negative photoresist can also be used.

[0090] The manufacturing process for the transparent conductor 10A, i.e., the structuring process for the transparent conductor 10, is not limited to the method described above using a photoresist and can, for example, be a printing process. In the case of a printing process, a portion of the surface of the second metal oxide layer 16 in the transparent conductor 10 is structured. Fig.1. A color is applied according to the shape of a pattern, for example, by an inkjet printing, screen printing, or gravure printing process. After printing, the part is etched with an acidic etching solution without the applied ink. This dissolves the second metal oxide layer 16, the third metal oxide layer 14, and the metal layer 18 to form the second laminated section 22. The ink is then removed. In this way, the transparent conductor 10A is successfully obtained.

[0091] The transparent ladder 10 in Fig. 1 and the transparent 10A conductor in Fig.2. Any layer can be placed between two adjacent layers. For example, a hard layer can be inserted between the transparent substrate 11 and the first metal oxide layer 12, and an etch-resistant layer can be inserted between the metal layer 18 and the first metal oxide layer 12. A water vapor barrier layer can be inserted between the transparent substrate 11 and the transparent electrode 20. A pair of hard layers can surround the transparent substrate 11 in a sandwich arrangement. Another metal oxide layer with a different composition than the first metal oxide layer 12, or a metal nitride layer, can be provided between the transparent substrate 11 and the first metal oxide layer 12.

[0092] The transparent conductors 10 and 10A have been sufficiently improved with respect to conductivity, flexibility, and corrosion resistance and can therefore be used for electrodes in organic devices such as organic EL displays, organic EL lighting, and organic thin-film solar cells. In this case, the first metal oxide layer 12, the metal layer 18, the third metal oxide layer 14, and the second metal oxide layer 16 function as the transparent electrode 20. The transparent electrode 20 can be either an anode or a cathode. [Third embodiment]

[0093] Fig.Figure 3 shows a schematic cross-sectional view illustrating the third embodiment of the transparent conductor. The transparent conductor 10B comprises a film-like transparent substrate 11, a first metal oxide layer 12, a metal layer 18, and a second metal oxide layer 16 in the order shown. That is, the transparent conductor 10B differs from the transparent conductor 10 of the first embodiment described above in that the transparent conductor 10B does not include the third metal oxide layer 14. The other configurations are the same as in the first embodiment.

[0094] The transparent conductor 10B contains the first metal oxide layer 12, which consists of a metal oxide different from ITO. This configuration can prevent corrosion of the metal layer 18 more reliably than in transparent conductors where the metal layer 18 is enclosed by ITO-containing metal oxide layers.

[0095] The work function of the surface 16a of the second metal oxide layer 16 is preferably 4.5 eV or more, more preferably 4.7 eV or more, even more preferably 5.0 eV or more, and particularly preferably 5.1 eV. By setting such a high work function, the transparent conductor 10B can be suitablely used as a transparent conductor for organic components.

[0096] The ratio (B / A) in the surface 16a of the second metal oxide layer 16 can be 1.0 × 10 -3 or less, or 8 × 10 -4 or less, or 7 × 10 -4 or less. The lower limit of the ratio (B / A) could be, for example, 1 × 10 -6 This allows the work function to be increased, and the transparent conductor 10B can be used appropriately as a transparent conductor for organic components. <Organisches Gerät>

[0097] Fig.Figure 4 shows a schematic diagram of an embodiment of the organic device. The organic device 100 is, for example, an organic EL illuminator and comprises a laminate with a transparent substrate 11, a transparent electrode (anode) 20, an impurity transport layer 30, a luminescent layer 40, an electron transport layer 50, and a metal electrode (cathode) 60 in the order shown. The transparent conductor 10 can be used as a transparent substrate 11 and a transparent electrode 20 in the organic device 100.

[0098] The transparent conductor 10 is designed such that the surface of the second metal oxide layer 16 in the transparent electrode 20 (surface 16a in Fig.1) is in contact with the impurity transport layer 30. A current source 80 is connected to the transparent electrode 20, which acts as the anode, and the metal electrode 60, which acts as the cathode. By applying an electric field through the current source 80, impurities are injected from the transparent electrode 20 into the impurity transport layer 30 and simultaneously electrons are injected from the metal electrode 60 into the electron transport layer 50.

[0099] Impurities injected into the impurity transport layer 30 and electrons injected into the electron transport layer 50 couple back together in the luminescence layer 40. This feedback causes an organic compound in the luminescence layer 40 to emit light. The light generated by this emission penetrates the impurity transport layer 30, the transparent electrode 20, and the transparent substrate 11, and is emitted from a side surface 20a of the organic component 100.

[0100] The organic device 100 uses the transparent conductor 10 as a transparent substrate 11 and transparent electrode 20. Accordingly, impurities can be efficiently injected from the transparent electrode 20 into the impurity transport layer 30. This increases the light output of the organic device 100. The light output of the organic device 100 can be sufficiently increased by reducing the carrier density of the second metal oxide layer 16 contained in the transparent electrode 20 and by increasing the work function of the surface 16a of the second metal oxide layer 16.

[0101] The impurity transport layer 30, the luminescence layer 40, the electron transport layer 50, and the metal electrode (cathode) 60 can each be formed with a common material. Examples of materials for the entire transport layer 30 are aromatic amine compounds. Examples for the luminescence layer 40 are those with a two-component system containing a combination of a host material and a dopant. Examples of the host material are 1,10-phenanthroline derivatives, organometallic complex compounds, aromatic hydrocarbons such as naphthalene, anthracene, naphthacene, perylene, benzofluoranthene, and naphthofluoranthene and their derivatives, as well as styrylamine and tetraaryldiamine derivatives. Examples of the dopant are benzodifluoranthene derivatives and coumarin derivatives.

[0102] The electron transport layer 50 can be formed with an organic material, such as a compound with a trinitrofluorenone, oxadiazole, or triazole structure, and using an inorganic material, such as an alkali metal like lithium, lithium fluoride, or lithium oxide. For the metal electrode 60, a metal electrode consisting of a metallic material such as aluminum, an organometallic complex, or a metal compound can be used. Each layer can be formed using a uniform method, such as a vacuum deposition method, an ionization deposition method, or another deposition method.

[0103] Although embodiments of the present disclosure have been described above, the present disclosure is not limited to the embodiments described above. For example, the organic component can be used in Fig.4. The transparent conductor 10A or the transparent conductor 10B is included instead of the transparent conductor 10. The organic component is not limited to organic EL lighting, as in Fig. 4 shown, but could be, for example, an organic EL display or an organic thin-film solar cell. Examples

[0104] The following section describes the present disclosure in more detail with reference to examples and comparative examples; however, the present disclosure is not limited to these examples. [Example 1](Production of a transparent conductor)

[0105] A transparent conductor with a laminate structure was used, as in Fig.Figure 1 shows how the transparent conductor was manufactured. The transparent conductor had a laminate structure in which a transparent substrate, a first metal oxide layer, a metal layer, a third metal oxide layer, and a second metal oxide layer were laminated in the sequence shown. This transparent conductor was manufactured as follows.

[0106] A commercially available polyethylene terephthalate film (thickness: 125 µm) was produced. This PET film was used as a transparent substrate. A first metal oxide layer, a metal layer, a third metal oxide layer, and a second metal oxide layer were successively formed on the transparent substrate by direct current magnetron sputtering.

[0107] A first metal oxide layer (thickness: 40 nm) was formed on the transparent substrate under reduced pressure (0.5 Pa) in a mixed gas atmosphere of argon and oxygen by direct current magnetron sputtering using a target consisting of three components: zinc oxide, indium oxide, and titanium oxide. Since the zinc oxide, indium oxide, and titanium oxide in the first metal oxide layer were converted to ZnO, In₂O₃, and TiO₂, respectively, the ZnO content was 74 mol%, the In₂O₃ content was 15 mol%, and the TiO₂ content was 11 mol%, based on the sum of the three components.

[0108] A metal layer (thickness: 10 nm) was formed on the first metal oxide layer under reduced pressure (0.5 Pa) in an argon gas atmosphere by direct current magnetron sputtering using a target made of a silver alloy consisting of Ag, Pd, and Cu. The mass ratio of the metals in the silver alloy from which the metal layer is made was Ag:Pd:Cu = 99.0:0.7:0.3.

[0109] A third metal oxide layer (thickness: 20 nm) was formed on the metal layer under reduced pressure (0.5 Pa) in a mixed gas atmosphere of argon and oxygen by direct current magnetron sputtering using a target consisting of four components: zinc oxide, indium oxide, titanium oxide, and tin oxide. Since the zinc oxide, indium oxide, titanium oxide, and tin oxide in the third metal oxide layer were converted to ZnO, In₂O₃, TiO₂, and SnO₂, respectively, the content of ZnO was 35 mol%, the content of In₂O₃ was 29 mol%, the content of TiO₂ was 14 mol%, and the content of SnO₂ was 22 mol%, based on the sum of the four components.

[0110] A second metal oxide layer (thickness: 20 nm, ITO layer) was formed on the third metal oxide layer under reduced pressure (0.5 Pa) in a mixed gas atmosphere of argon and oxygen by direct current magnetron sputtering using an ITO target. The oxygen to argon flux ratio during DC magnetron sputtering was 1.1 volume percent. This flux ratio is standard (25°C, 1 bar), and the same applies to the following examples and comparisons. (Evaluation of the transparent leader)

[0111] The overall light transmittance (transmission) of the manufactured transparent conductor was measured using an opacity meter (product name: NDH-7000, manufactured by NIPPON DENSHOKU INDUSTRIES CO., LTD.). Measurement results of 85% or higher were rated "A" and those of less than 85% were rated "B". The results are shown in the "Transmission" column of Table 1.

[0112] The surface resistance of the transparent conductor, fabricated against the side of the transparent substrate, was measured using a four-terminal measuring device (product name: Loresta GP, manufactured by Mitsubishi Chemical Corporation). Measurements of 30 Ω / m² or less were rated "A", and those above 30 Ω / m² were rated "B". The results are shown in the "Surface Resistance" column of Table 1.

[0113] The work function of the surface of the second metal oxide layer in the fabricated transparent conductor was measured using a photoelectron spectrometer (manufactured by RIKEN KEIKI Co., Ltd., product name: FAC-1). The results are shown in the "Work Function" column of Table 1.

[0114] The flexibility of the manufactured transparent conductor was evaluated using the following procedure. A 5 mm diameter mandrel was wrapped with the transparent conductor to bend it at an angle of 180°. After the mandrel was wrapped, the surface resistance measurement described above was performed. Cases where no difference was found between the surface resistance value before and after wrapping the mandrel were rated "A", and cases where a difference was found were rated "B". Cases where such a difference was within the measurement error range of the four-pole resistance meter were also rated "A". The results are shown in the "Flexibility" column of Table 1. The numerical values ​​in the column are surface resistance values ​​after wrapping.

[0115] The corrosion resistance of the manufactured transparent conductor was evaluated using the following procedure. The transparent conductor was stored for 240 hours in a high-temperature / high-humidity environment of 60°C and 90% relative humidity. Cases in which no discoloration was subsequently found by visual inspection were rated "A". Cases in which a tiny discolored area (approx. 1 mm) was observed were rated "A". 2 Cases where a discolored area larger than the area found (or smaller) were rated "B", and cases where a discolored area larger than the "B" cases was found were rated "C". The results are shown in the "Corrosion Resistance" column in Table 1. [Example 2]

[0116] A transparent conductor was fabricated and evaluated under the same conditions as in Example 1, except that the oxygen gas to argon gas flow rate ratio during the formation of the second metal oxide layer by direct current magnetron sputtering was changed to 1.7 volume percent. The evaluation results are shown in Table 1. [Example 3]

[0117] A transparent conductor was fabricated and evaluated under the same conditions as in Example 1, except that the flow rate ratio of oxygen gas to argon gas during the formation of the second metal oxide layer by direct current magnetron sputtering was changed to 2.4 volume percent. The results of the evaluations are shown in Table 1. [Example 4]

[0118] A transparent conductor was fabricated and evaluated under the same conditions as in Example 1, except that the oxygen gas to argon gas flow rate ratio during the formation of the second metal oxide layer by direct current magnetron sputtering was changed to 3.0 volume percent. The evaluation results are shown in Table 1. [Example 5]

[0119] A transparent conductor was fabricated and evaluated under the same conditions as in Example 1, except that the oxygen gas to argon gas flow rate ratio during the formation of the second metal oxide layer by direct current magnetron sputtering was changed to 4.3 volume percent. The evaluation results are shown in Table 1. [Example 6]

[0120] A transparent conductor was fabricated in the same manner as in Example 4, except that the third metal oxide layer was omitted and the thickness of the second metal oxide layer (ITO layer) was changed to 40 nm. This transparent conductor comprised the transparent substrate, the first metal oxide layer, the metal layer, and the second metal oxide layer in that order. The evaluation of this transparent conductor was performed in the same manner as in Example 1. The results are presented in Table 3. [Table 1] Transmission (%) Surface resistance (Ω / m²) Exit work (eV) Flexibility (Ω / m²) Corrosion resistance Example 1 A (88,7) A (8,8) 4,6 A (8,8) A Example 2 A (88,3) A (8,6) 4,8 A (8,6) A Example 3 A (88,6) A (8,7) 5,0 A (8,7) A Example 4 A (88,8) A (8,9) 5,1 A (8,9) A Example 5 A (88,4) A (8,8) 5,2 A (8,8) A Example 6 A (88,5) A (8,5) 5,1 A (8,5) B

[0121] In Table 1, the numerical values ​​in parentheses in the columns "Transmission," "Surface Resistance," and "Flexibility" represent measurements. As shown in Table 1, it was confirmed that the work function tends to increase with increasing oxygen content during the formation of the second metal oxide layer. The transparent conductors in Examples 1 to 6 each exhibited a surface resistance of 9 Ω / m² or less and were thus confirmed as conductive. Furthermore, it was confirmed that the transparent conductors in Examples 1 to 6 are improved with respect to flexibility and corrosion resistance. Among them, the transparent conductors in Examples 1 to 5 were confirmed as having sufficiently improved corrosion resistance. (Evaluation of the elemental properties of an organic building component)

[0122] Under the same conditions as in Examples 1 to 5, except that a glass substrate was used as the transparent substrate instead of the PET film, a first metal oxide layer, a metal layer, a third metal oxide layer, and a second metal oxide layer were successively deposited over the transparent substrate to obtain transparent conductors. An impurity transport layer (thickness: 50 nm), a luminescence layer containing tris(8-quinolinolato)aluminum (thickness: 50 nm), an electron transport layer containing LiF (thickness: 12 nm), and an aluminum electrode (300 nm) were each deposited by vapor deposition over the surface of the second metal oxide layer in each transparent conductor to obtain organic EL light-emitting elements, as shown in Fig. 4 shown.

[0123] For each organic EL luminescent element obtained, voltage values ​​were measured when a current was applied. The results are presented in Fig.5 shown. Fig. Figure 5 shows that the ability of impurity injection from the transparent conductor into the organic layer is higher when the current density (one current value per unit area) is higher at the same voltage value. This means that the organic EL light-emitting elements can be operated at a lower voltage when the current density is higher.

[0124] The current densities at a voltage of 10 V are shown in Table 2. Fig. As confirmed in section 5 and Table 2, the current density and the defect injection capability increase with increasing work function. A current density of 5 mA / cm² 2 or higher was achieved at a voltage of 10 V or lower when the work function was 5.0 eV or higher. This confirmed that sufficiently improved element properties can be achieved. [Table 2] Exit work (eV) Current density (mA / cm³) 2 ) Example 1 4,6 1,0 Example 2 4,8 3,5 Example 3 5,0 8,0 Example 4 5,1 13,5 Example 5 5,2 >25 [Reference example 1]

[0125] A second metal oxide layer (ITO monolayer) was formed on the commercially available polyethylene terephthalate film used in Example 1, using the same procedure as in Example 1. The surface resistivity and work function of this ITO monolayer were measured in the same way as in Example 1. The resistivity of the ITO monolayer was determined from the product of the surface resistivity and the thickness of the ITO monolayer. Furthermore, the carrier density of the ITO monolayer was measured using a Hall effect meter (manufactured by ECOPIA, product name: HMS-3000). The results are shown in Table 3. [Reference example 2]

[0126] A second metal oxide layer (ITO monolayer) was formed on the commercially available polyethylene terephthalate film used in Example 2, using the same procedure as in Example 2. The surface resistivity and work function of this ITO monolayer were measured in the same way as in Example 1. The resistivity and carrier density of the ITO monolayer were measured in the same way as in reference Example 1. The results are shown in Table 3. [Reference example 3]

[0127] A second metal oxide layer (ITO monolayer) was formed on the commercially available polyethylene terephthalate film used in Example 3, using the same procedure as in Example 3. The surface resistivity and work function of this ITO monolayer were measured in the same way as in Example 1. The resistivity and carrier density of the ITO monolayer were measured in the same way as in reference Example 1. The results are shown in Table 3. [Reference example 4]

[0128] A second metal oxide layer (ITO monolayer) was formed on the commercially available polyethylene terephthalate film used in Example 4, using the same procedure as in Example 4. The surface resistivity and work function of this ITO monolayer were measured in the same way as in Example 1. The resistivity and carrier density of the ITO monolayer were measured in the same way as in reference Example 1. The results are shown in Table 3. [Reference example 5]

[0129] A second metal oxide layer (ITO monolayer) was formed on the commercially available polyethylene terephthalate film used in Example 5 using the same procedure as in Example 5. The surface resistivity and work function of this ITO monolayer were measured in the same way as in Example 1. The resistivity and carrier density of the ITO monolayer were measured in the same way as in reference Example 1. The measurement results are shown in Table 3. [Table 3] Surface resistance (Ω / m²) Specific resistance (Ω·cm) Exit work (eV) Hall measurement (cm) -3 ) Reference example 1 270 5,4×10 4 4,6 8,0×10 20 Reference example 2 190 3,8×10 -4 4,8 5,5×10 20 Reference example 3 250 5,0×10 4 5,0 3,5×10 20 Reference example 4 430 8,6×10 -4 5,1 2,4×10 20 Reference example 5 1350 2,7×10 -3 5,2 1,2×10 20

[0130] The work functions in reference examples 1 to 5 in Table 3 corresponded to the work functions in examples 1 to 5 in Table 1. This confirmed that the work function is not affected by the composition of the inner layers and is a property determined by the second metal oxide layer. Furthermore, it was confirmed that the surface resistivity and the resistivity of the second metal oxide layer are influenced by the oxygen gas ratio during the formation of the second metal oxide layer. This suggests that a change in the oxygen gas ratio during the formation of the second metal oxide layer leads to a change in the structure of the second metal oxide layer. Additionally, Table 3 shows that the support density decreases with increasing work function, resulting in deteriorated surface resistivity values.This suggests that it is difficult for transparent conductor films consisting of an ITO monolayer to achieve a combination of high work function and low resistance.

[0131] Fig. Figure 6 shows a diagram illustrating the relationship between carrier density and work function for the ITO monolayers in reference examples 1 to 5. It was confirmed that carrier density and work function are nearly proportional to each other, and that the work function increases with decreasing carrier density. When the carrier density [cm³] -3 ] and the work function [eV] were denoted as x and y respectively, their correlation equation was y = -9 × 10 -22 x + 5.3269, and the correlation coefficient (r) 2 ) was 0.9943. To set the work function to 5.0 eV or higher, it is necessary to increase the carrier density to 3.5 × 10 20 cm -3 or set it lower. [Comparison example 1]

[0132] An ITO layer (thickness: 40 nm) was formed on the commercially available polyethylene terephthalate film used in Example 1 under the same conditions as for the formation of the second metal oxide layer in Example 4 (oxygen gas to argon gas flow ratio: 3.0 volume percent). This resulted in a transparent conductor consisting of the transparent substrate and the ITO layer. The evaluation of this transparent conductor was performed in the same manner as in Example 1. The results are presented in Table 4. [Comparative example 2]

[0133] An ITO layer (thickness: 150 nm) was formed on the commercially available polyethylene terephthalate film used in Example 1 under the same conditions as for the formation of the second metal oxide layer in Example 4 (oxygen gas to argon gas flow ratio: 3.0 volume percent). This resulted in a transparent conductor consisting of the transparent substrate and the ITO layer. The evaluation of this transparent conductor was performed in the same manner as in Example 1. The results are presented in Table 4. [Comparative example 3]

[0134] An ITO layer (thickness: 40 nm) was formed on the commercially available polyethylene terephthalate film used in Example 1 under the same conditions as for the formation of the second metal oxide layer in Example 4 (oxygen gas to argon gas flow ratio: 3.0 volume percent). A metal layer, identical to that in Example 1, was then formed on this ITO layer. A further ITO layer (thickness: 40 nm) was then formed on this metal layer under the same conditions as for the formation of the second metal oxide layer in Example 4 (oxygen gas to argon gas flow ratio: 3.0 volume percent). In this way, a transparent conductor was obtained, including the transparent substrate, the ITO layer, the metal layer, and the ITO layer, laminated in the specified order. The evaluation of this transparent conductor was performed in the same manner as in Example 1.The results are shown in Table 4. [Comparative example 4]

[0135] The procedures in Comparative Example 3 were carried out up to and including the formation of a metal layer. A metal oxide layer (thickness: 40 nm) consisting of zinc oxide, indium oxide, titanium oxide, and tin oxide was formed on the metal layer. This metal oxide layer was formed using the same method as the third metal oxide layer in Example 1. Accordingly, this transparent conductor comprised the transparent substrate, the ITO layer, the metal layer, and the metal oxide layer (corresponding to the third metal oxide layer in Example 1) in the order shown. The evaluation of this transparent conductor was performed in the same manner as in Example 1. The results are presented in Table 4.

[0141] [Table 4] Transmission(%) Surface resistance (Ω / q) m ) Exit work (eV) Flexibility (Ω / m²) Corrosion resistance Comparative example 1 B (83,4) B (40) 5,1 A (40) A Comparative example 2 A (86,0) A (13) 5,1 B (non-measurable) A Comparative example 3 A (88,1) A (8,7) 5,1 A (8,7) c Comparative example 4 A (88,1) A (8,5) 4,4 A (8,5) B

[0136] In Table 4, the numerical values ​​in parentheses in the "Transmission," "Surface Resistance," and "Flexibility" columns represent measurements. As can be seen from Table 4, at least one of the conductivity, flexibility, and corrosion resistance ratings was "B" for the transparent conductors in Comparison Examples 1 to 4. The surface resistance value in Comparison Example 1 was higher than in any other example. The surface resistance was successfully reduced by the increased thickness of the ITO layer in Comparison Example 1; however, the ITO layer was damaged in the flexibility rating, becoming an insulating film. The corrosion resistances in Comparison Examples 3 and 4 were poor compared to Examples 1 to 5 because the ITO layer and the metal layer were in contact with each other. [Examples 7 to 10]

[0137] Transparent conductors were fabricated and evaluated in the same manner as in Example 4, except that the thickness of the second metal oxide layer was changed as shown in Table 5, and the thickness of the third metal oxide layer was changed accordingly to adjust the combined thickness of the second and third metal oxide layers to 40 nm. The results are presented in Table 5. [Table 5] Thickness of the second metal oxide layer (nm) Transmission(%) Surface resistance (Ω / m²) Exit work (eV) Flexibility (Ω / m²) Corrosion resistance Example 7 2 A (88,3) A (8,9) 5,1 A (8,9) A Example 8 5 A (88,7) A (8,9) 5,1 A (8,9) A Example 9 10 A (88,8) A (8,9) 5,1 A (8,9) A Example 10 15 A (88,4) A (8,9) 5,1 A (8,9) A

[0138] In Table 5, the numerical values ​​in parentheses represent measurements. As shown in Table 5, it was confirmed that the transparent conductors in Examples 7 to 10 exhibit improved conductivity, flexibility, and corrosion resistance. Furthermore, it was confirmed that the work function is hardly dependent on the thickness of the third metal oxide layer. [Example 11]

[0139] A first metal oxide layer, a metal layer, and a third metal oxide layer were formed on a transparent substrate in the same sequence as shown in Example 1. Subsequently, a second metal oxide layer (thickness: 20 nm, ITO layer) was formed on the third metal oxide layer under reduced pressure (0.5 Pa) in a mixed gas atmosphere of argon and oxygen by DC magnetron sputtering using an ITO target. The oxygen-to-argon flux ratio during DC magnetron sputtering was approximately 6.5 volume percent. This resulted in the transparent conductor shown in Example 11. [Example 12]

[0140] A transparent conductor was produced under the same conditions as in Example 11, except that the flow rate ratio of oxygen gas to argon gas during the formation of the second metal oxide layer by direct current magnetron sputtering was changed to about 2.2 volume percent. [Comparative example 5]

[0141] A transparent conductor was produced under the same conditions as in Example 1, except that the flow rate ratio of oxygen gas to argon gas during the formation of the second metal oxide layer by direct current magnetron sputtering was changed to 0 volume percent. (XPS measurement)

[0142] X-ray photoelectron spectroscopy was performed on the surface of the second metal oxide layer in Example 11, Example 12, and Comparative Example 5 using a commercially available instrument (manufactured by ULVAC-PHI, Inc., product name: QUANTERA II). Following this analysis, the surface of the second metal oxide layer was sputter-etched by irradiation with an Ar-ion beam in a scanning mode to remove a portion of the surface of the second metal oxide layer to a depth of 1.7 nm. X-ray photoelectron spectroscopy was then performed on the interior of the second metal oxide layer, which had been exposed by such Ar-ion etching in the same manner as in the surface analysis.

[0143] The Fig. 7(A), Fig. 8, Fig. 9, Fig. 10(A) and Fig.Figure 11 shows X-ray photoelectron spectra for Example 11, Example 12 and Comparative Example 5 before Ar ion etching. Fig. Figure 7(A) shows X-ray photoelectron spectroscopy spectra, including a binding energy range from 0.5 to 2.3 eV, which was determined for the surface of the second metal oxide layer in Example 11, Example 12, and Comparative Example 5. Fig. Figures 7 to 11 each show two spectra for Example 11, Example 12, and comparison example 5, as the measurement was performed twice for each example and comparison example. As in Fig. As shown in Figure 7(A), the spectra for examples 11 and 12 differed in their form from those of the comparison example 5.

[0144] Fig.Figure 8 shows an enlarged view of the spectra of the X-ray photoelectron spectroscopy with a binding energy range of 0.5 to 2.3 eV for the surface of the second metal oxide layer in Example 11 and Comparative Example 5 before Ar ion etching. Fig. Figure 9 shows an enlarged view of the X-ray photoelectron spectroscopy spectra with a binding energy range of 0.5 to 2.3 eV for the surface of the second metal oxide layer in Example 12 and Comparative Example 5 before Ar ion etching. Fig. Figure 8 shows two X-ray photoelectron spectra for Example 11, Examples 11-1 and 11-2. Fig. Figure 9 shows two X-ray photoelectron spectra for Example 12, Examples 12-1 and 12-2. Similarly, in the Fig. 8 and Fig. 9 Two spectra for the comparative example 5, examples 5-1 and 5-2, are shown. As in the Fig. 7(A), Fig. 8 and Fig.As shown in Figure 9, it was found that the spectra for Example 11 and Example 12 have shifted downwards compared to those of the comparison example 5.

[0145] Fig. Figure 10(A) shows X-ray photoelectron spectroscopy spectra with a binding energy range of 14 to 21 eV for the surface of the second metal oxide layer in Example 11, Example 12, and Comparative Example 5 before Ar ion etching. This binding energy range includes an indium [In4d] peak. This peak was observed at nearly the same position (same binding energy) in X-ray photoelectron spectra for Example 11, Example 12, and Comparative Example 5.

[0146] Fig.Figure 11 shows X-ray photoelectron spectroscopy spectra in a binding energy range of approximately 276 to 293 eV for the surface of the second metal oxide layer in Example 11, Example 12, and Comparative Example 5 before Ar ion etching. The peak around 284.8 eV is derived from carbon [C1s]. This peak was observed at almost the same position in the X-ray photoelectron spectroscopy spectra (Example 11, Example 12, and Comparative Example 5).

[0147] From the X-ray photoelectron spectra described above, the peak area A in a binding energy range of 14 to 21 eV and the peak area B in a binding energy range of 0.5 to 2.3 eV were calculated. Before calculating the peak areas A and B, the shift correction and background correction described above were performed. The values ​​of the peak areas A and B and the ratios (B / A) were as shown in Table 1. Since the X-ray photoelectron spectroscopy for Examples 1 and 2 and the comparison example 1 was performed twice each, the ratios (B / A) in Table 6 are each presented as the mean of two measurements.

[0148] The Fig. 7(B) and Fig. Figure 10(B) shows X-ray photoelectron spectroscopy spectra for the exposed surface of the second metal oxide layer in Example 11, Example 12, and Comparative Example 5 after Ar ion etching. The comparison between Fig. 7(A) and Fig. Figure 7(B) shows that the X-ray photoelectron spectroscopy spectra for the surface and the interior of the second metal oxide layer are different. This suggests that the surface states of the two are different. As in Fig. As shown in Figure 7(B), the spectra of the X-ray photoelectron spectroscopy after Ar ion etching did not differ as much between Example 11, Example 12 and the comparison example 5 as before the Ar ion etching.

[0149] The peak areas A and B for the exposed surface after Ar ion etching were determined in the same way as for the surface before Ar ion etching, and the ratio between peak area A and peak area B, (B / A)', was calculated. The results are shown in Table 7. (Evaluation of transparent ladders)

[0150] Work function, total light transmittance, surface resistivity, flexibility, and corrosion resistance were determined for Example 11, Example 12, and Comparative Example 5 in the same manner as in Example 1. The results are shown in Table 6. [Table 6] Example 11 Example 12 Comparative example 5 Exit work (eV) 5,08 4,73 4,46 n=1 n=2 n=1 n=2 n=1 n=2 Peak area A 324,514 321,038 331,742 326,497 318,145 310,989 Peak area B 206 211 199 170 343 363 Ratio (B / A) (average value) 6,6×10- 4 5,6×10 -4 1,1×10 -3 Transmission (%) 88,8 88,3 88,5 Surface resistance (Ω / m²) 8,9 8,6 8,8 Flexibility (Ω / m²) A (8,9) A (8,6) A (8,8) Corrosion resistance A A A

[0151] As shown in Table 6, the transparent conductors in Example 11 and Example 12, each with a smaller B / A ratio than in Comparison Example 5, had a higher work function than the conductor in Comparison Example 5. The transparent conductor in Example 11 had the highest work function. Both the transparent conductors in Example 11 and Example 12 exhibited high overall light transmittance, and their surface resistivity values ​​were sufficiently low. Furthermore, the transparent conductors in Example 11 and Example 12 showed improved flexibility and corrosion resistance. [Table 7] Example 11 Example 12 Comparative example 5 n=1 n=2 n=1 n=2 n=1 n=2 Peak area A 358,578 354,622 383,789 374,225 368,134 360,310 Peak area B 355 341 463 395 449 444 Ratio (B / A)'(average value) 9,8×10 -4 1,1×10 -3 1,2×10 -3

[0152] As can be seen from Table 7, the values ​​of the ratio (B / A)' between Example 11, Example 12, and the comparison example 5 did not differ significantly from those of the ratio (B / A) in Table 6. In both Example 11 and Example 12, the ratio (B / A) in Table 6 was smaller than the ratio (B / A)' in Table 7. From this, it is deduced that the work function is higher when the position approaches the surface of the second metal oxide layer. Industrial applicability

[0153] According to the present disclosure, a transparent conductor with improved conductivity, flexibility, and corrosion resistance can be provided. By incorporating the transparent conductor, an organic component with improved performance, flexibility, and corrosion resistance can be provided. According to the present disclosure, a transparent conductor with improved conductivity and high work function can be provided. By incorporating the transparent conductor described above, an organic component with improved performance can be provided. List of reference symbols

[0154] 10, 10A, 10B: transparent conductor, 11: transparent substrate, 12: first metal oxide layer, 16: second metal oxide layer, 14: third metal oxide layer, 16a: surface, 18: metal layer, 20: transparent electrode, 21: first laminated section, 22: second laminated section, 30: impurity transport layer, 40: luminescence layer, 50: electron transport layer, 60: metal electrode, 80: power source, 100: organic device.

Claims

[1] A transparent conductor (10) consisting of: A transparent substrate (11); a first metal oxide layer (12); a metal layer (18) containing a silver alloy; a third metal oxide layer (14); and a second metal oxide layer (16), in the order mentioned, wherein the first metal oxide layer (12) consists of a metal oxide which differs from ITO, the second metal oxide layer (16) contains ITO, the third metal oxide layer (14) consists of a metal oxide which differs from ITO and which contains zinc oxide, indium oxide, titanium oxide and tin oxide, a work function of a surface (16a) of the second metal oxide layer (16) relative to a metal layer side is 4.5 eV or more and the second metal oxide layer (16) and the third metal oxide layer (14) are in direct contact with each other. [2] Transparent conductor (10) according to claim 1, wherein the thickness of the third metal oxide layer (14) is 5 nm or more. [3] Transparent conductor (10) according to claim 1 or 2, wherein the first metal oxide layer (12) contains zinc oxide, indium oxide and titanium oxide. [4] Transparent conductor (10) according to one of claims 1 to 3, wherein the carrier density of the second metal oxide layer (16) is 3.5 × 10 20 [cm -3 ] or less. [5] A transparent conductor (10) consisting of: a transparent substrate (11); a first metal oxide layer (12); a metal layer (18) containing a silver alloy; a third metal oxide layer (14); and a second metal oxide layer (16), in the order mentioned, wherein the second metal oxide layer (16) contains ITO, the third metal oxide layer (14) consists of a metal oxide which differs from ITO and which contains zinc oxide, indium oxide, titanium oxide and tin oxide, a ratio of the peak area B in a binding energy range of 0.5 to 2.3 eV to the peak area A in a binding energy range of 14 to 21 eV (B / A) in an X-ray photoelectron spectrum for a surface of the second metal oxide layer (16) 1.0 × 10 -3 or less the second metal oxide layer (16) and the third metal oxide layer (14) are in direct contact with each other. [6] Transparent conductor (10) according to claim 5, wherein the thickness of the third metal oxide layer (14) is 5 nm or more. [7] Transparent conductor (10) according to claim 6, wherein the first metal oxide layer (12) contains zinc oxide, indium oxide and titanium oxide. [8] Transparent conductor (10) according to any one of claims 5 to 7, wherein the work function of the surface (16a) of the second metal oxide layer (16) is 4.5 eV or more. [9] Transparent conductor (10) according to any one of claims 1 to 8, wherein the thickness of the second metal oxide layer (16) is 2 nm or more. [10] Transparent conductor (10) according to any one of claims 1 to 9, wherein the surface resistance of the transparent conductor on one side of the second metal oxide layer is 30 Ω / m² or less. [11] An organic device (100) comprising the transparent conductor (10) according to any one of claims 1 to 10.

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