JPWO2014171149A1 - Transparent conductor and method for producing the same - Google Patents

Abstract

An object of the present invention is to provide a transparent conductor that has little deterioration over time, has high light transmittance, and has a sufficiently low surface electric resistance value. In order to solve the above problems, the present invention provides a transparent substrate, a high refractive index layer containing a dielectric material or an oxide semiconductor material having a refractive index higher than the refractive index of light having a wavelength of 570 nm of the transparent substrate, and a thickness of 5 nm. A transparent metal film having a thickness of ˜15 nm, an intermediate layer including a dielectric material or an oxide semiconductor material, and a barrier layer including the dielectric material or the oxide semiconductor material and having a higher packing density than the intermediate layer in this order It is a transparent conductor, and at least one of the intermediate layer and the barrier layer includes a dielectric material or an oxide semiconductor material having a refractive index higher than the refractive index of light having a wavelength of 570 nm of the transparent substrate, and has a wavelength of 450 nm to 800 nm. A transparent conductor having an average light transmittance of 50% or more.

Description

  The present invention relates to a transparent conductor and a manufacturing method thereof.

  Transparent conductive films are used in various devices such as electrode materials for display devices such as liquid crystal displays, plasma displays, inorganic and organic EL (electroluminescence) displays, electrode materials for inorganic and organic EL elements, touch panel materials, and solar cell materials. ing.

As a material constituting such a transparent conductive film, metals such as Au, Ag, Pt, Cu, Rh, Pd, Al, and Cr, In ₂ O ₃ , CdO, CdIn ₂ O ₄ , Cd ₂ SnO ₄ , and TiO _{2 are used.} , SnO ₂ , ZnO, ITO (indium tin oxide) and other oxide semiconductors are known. Among these, a transparent conductive film made of ITO is frequently used from the viewpoint of light transmittance and conductivity.

  In recent years, a capacitive touch panel has been developed. In this method, a transparent conductive film having a low surface electrical resistance value and high transparency is required. However, with an ITO film, it is difficult to sufficiently reduce the surface electrical resistance value. In addition, the ITO film is easily broken and cannot be applied to applications that require flexibility.

  Therefore, a transparent conductive film in which Ag is arranged in a mesh shape has been proposed as a transparent conductive film replacing the ITO film (Patent Document 1). However, the transparent conductive film of Patent Document 1 has an Ag mesh width of about 20 μm. Therefore, the Ag mesh is easily visible and cannot be applied to uses that require high transparency. Furthermore, although it conducts at the mesh portion, it does not sufficiently conduct at the gap portion of the mesh. As a result, the surface electrical resistance value of the transparent conductive film could not be lowered sufficiently.

  A transparent conductive film containing Ag nanowires has also been proposed (Patent Document 2). However, the transparent conductive film has a large surface electric resistance value, and the thickness of the transparent conductive film needs to be about 200 nm. For this reason, it has been difficult to apply the transparent conductive film to applications requiring flexibility.

On the other hand, it has been studied to use an Ag thin film as a transparent conductive film (Patent Document 3). A transparent conductor in which a niobium oxide (Nb ₂ O ₅ ) film, an Ag thin film, and an IZO (indium oxide / zinc oxide) film are stacked has also been proposed (Non-patent Document 1).

JP 2012-53644 A Special table 2009-505358 Special table 2011-508400 gazette

SID 2012 DIGEST p.352-353

  According to the transparent conductive film (Ag thin film), although the surface electric resistance value can be reduced, the transparent conductive film is easily affected by moisture in the atmosphere. For this reason, the surface electrical resistance of the transparent conductive film may increase over time, or the light transmission may decrease. Therefore, it has been studied to form a barrier layer on the transparent conductive film. However, the transparent conductive film is very thin. For this reason, when a dense barrier layer is formed on the transparent conductive film, the transparent conductive film is damaged during the formation of the barrier layer, and the surface electrical resistance of the transparent conductor may be increased. Further, the surface of the transparent conductive film was roughened by the formation of the barrier layer, and the localized plasmon absorption was likely to increase.

  The present invention has been made in view of such a situation. An object of the present invention is to provide a transparent conductor that is less deteriorated with time, has high light transmittance, and has a sufficiently low surface electric resistance, and a method for producing the same.

That is, the first of the present invention relates to the following transparent conductor.
[1] A transparent substrate, a high refractive index layer containing a dielectric material or an oxide semiconductor material having a refractive index higher than that of light having a wavelength of 570 nm of the transparent substrate, and a transparent metal film having a thickness of 5 nm to 15 nm A transparent conductor comprising, in this order, an intermediate layer containing a dielectric material or an oxide semiconductor material, and a barrier layer containing a dielectric material or an oxide semiconductor material and having a higher packing density than the intermediate layer, At least one of the intermediate layer and the barrier layer includes a dielectric material or an oxide semiconductor material having a refractive index higher than that of light having a wavelength of 570 nm of the transparent substrate, and has an average transmittance of light having a wavelength of 450 nm to 800 nm. A transparent conductor that is 50% or more.

[2] The refractive index of light at a wavelength of 570 nm of the dielectric material or oxide semiconductor material included in the barrier layer is 1.8 or more, and the wavelength of the dielectric material or oxide semiconductor material included in the intermediate layer is 570 nm. The transparent conductor according to [1], wherein the refractive index of light is less than 1.8.
[3] The dielectric material or oxide semiconductor material included in the intermediate layer is MgF ₂ , SiO ₂ , CaF ₂ , CeF ₃ , LaF ₃ , LiF, NaF, NdF ₃ , Na ₃ AlF ₆ , Al ₂ O ₃ , The transparent conductor according to [2], which is at least one selected from the group consisting of MgO and ThO ₂ .

[4] The dielectric material or oxide semiconductor material included in the barrier layer is HfO ₂ , Y ₂ O ₃ , La ₂ O ₃ , LaAlO ₃ , PrTiO ₃ , SiO _x N _y (x> 0, y> 0). , TiO ₂ , ITO, ZnO, ZnS, Nb ₂ O ₅ , ZrO ₂ , CeO ₂ , Ta ₂ O ₅ , Ti ₃ O ₅ , Ti ₄ O ₇ , Ti ₂ O ₃ , TiO, SnO ₂ , La ₂ Ti ₂ The transparent conductor according to any one of [1] to [3], which is one or more selected from the group consisting of O ₇ , IZO, AZO, GZO, ATO, and ICO.
[5] The dielectric material or oxide semiconductor material included in the high refractive index layer is TiO ₂ , ITO, ZnO, ZnS, Nb ₂ O ₅ , ZrO ₂ , CeO ₂ , Ta ₂ O ₅ , Ti ₃ O ₅ , [1] to [4], which are at least one selected from the group consisting of Ti ₄ O ₇ , Ti ₂ O ₃ , TiO, SnO ₂ , La ₂ Ti ₂ O ₇ , IZO, AZO, GZO, ATO, and ICO. A transparent conductor according to any one of the above.
[6] The transparent conductive film according to any one of [1] to [5], wherein the transparent metal film includes one or more metals selected from the group consisting of silver, copper, gold, platinum group, titanium, and chromium. body.

[7] When the equivalent admittance of the transparent conductor on the surface of the barrier layer is represented by Y _E = x _E + iy _E , and the refractive index of light having a wavelength of 570 nm of the member or environment in contact with the barrier layer surface is represented by n _{env ^{a, ((x E -n env)}} 2 + (y E) 2) satisfies 0.5 <0.5, [1] to transparent conductor according to any one of [6].

2nd of this invention is related with the manufacturing method of the following transparent conductors.
[8] A transparent substrate, a high refractive index layer containing a dielectric material or an oxide semiconductor material having a refractive index higher than that of light having a wavelength of 570 nm of the transparent substrate, and a transparent metal film having a thickness of 5 nm to 15 nm An intermediate layer containing a dielectric material or an oxide semiconductor material, and a barrier layer containing a dielectric material or an oxide semiconductor material and having a higher packing density than the intermediate layer in this order, the intermediate layer and the A method for producing a transparent conductor, wherein at least one of the barrier layers is a layer containing a dielectric material or an oxide semiconductor material having a refractive index higher than the refractive index of light having a wavelength of 570 nm of the transparent substrate, A step of preparing a laminate in which the high refractive index layer and the transparent metal film are laminated; a step of forming the intermediate layer on the transparent metal film; and And a step of forming the barrier layer by sputtering or ion assisted deposition, a method for producing a transparent conductor.

  According to the present invention, it is possible to obtain a transparent conductor that is less deteriorated with time, has high light transmittance, and has a sufficiently low surface electric resistance value.

It is a schematic sectional drawing which shows an example of the transparent conductor of this invention. FIG. 2A is a graph showing an admittance locus of a wavelength of 570 nm of the transparent conductor produced in Example 1. FIG. 2B is a graph showing the spectral characteristics of the transparent conductor produced in Example 1. FIG. 3A is a graph showing an admittance locus at a wavelength of 570 nm of a transparent conductor having a transparent substrate / transparent metal film / high refractive index layer. FIG. 3B is a graph showing admittance trajectories of a transparent conductor / transparent metal film / high refractive index layer having a wavelength of 450 nm, a wavelength of 570 nm, and a wavelength of 700 nm. 4A is a graph showing an admittance locus of a wavelength of 570 nm of the transparent conductor produced in Example 2. FIG. 4B is a graph showing the spectral characteristics of the transparent conductor produced in Example 2. FIG. FIG. 5A is a graph showing the admittance locus of the transparent conductor produced in Example 3 at a wavelength of 570 nm. FIG. 5B is a graph showing the spectral characteristics of the transparent conductor produced in Example 3. 6A is a graph showing an admittance locus of a wavelength of 570 nm of the transparent conductor produced in Example 4. FIG. FIG. 6B is a graph showing the spectral characteristics of the transparent conductor produced in Example 4. FIG. 7A is a graph showing an admittance locus of a wavelength of 570 nm of the transparent conductor produced in Example 5. FIG. 7B is a graph showing the spectral characteristics of the transparent conductor produced in Example 5. FIG. 8A is a graph showing the admittance locus of the transparent conductor produced in Example 6 at a wavelength of 570 nm. FIG. 8B is a graph showing the spectral characteristics of the transparent conductor produced in Example 6. FIG. 9A is a graph showing an admittance locus of a wavelength of 570 nm of the transparent conductor produced in Example 7. FIG. 9B is a graph showing the spectral characteristics of the transparent conductor produced in Example 7. FIG. 10A is a graph showing an admittance locus of the transparent conductor produced in Example 8 at a wavelength of 570 nm. FIG. 10B is a graph showing the spectral characteristics of the transparent conductor produced in Example 8. FIG. 11A is a graph showing the admittance locus of the transparent conductor produced in Comparative Example 1 at a wavelength of 570 nm. FIG. 11B is a graph showing the spectral characteristics of the transparent conductor produced in Comparative Example 1. FIG. 12A is a graph showing an admittance locus of the transparent conductor produced in Comparative Example 2 at a wavelength of 570 nm. 12B is a graph showing the spectral characteristics of the transparent conductor produced in Comparative Example 2. FIG.

1. About a transparent conductor The transparent conductor of this invention is applicable to the panel of various display elements, such as a touchscreen, an organic EL element, a solar cell. An example of the structure of the transparent conductor of the present invention is shown in FIG. The transparent conductor 100 of the present invention includes transparent substrate 1 / high refractive index layer 2 / transparent metal film 3 / intermediate layer 4 / barrier layer 5. In the transparent conductor 100 of the present invention, each layer formed on the transparent substrate 1 is a layer made of an inorganic material.

  As described above, a barrier layer may be necessary on the transparent metal film in order to suppress the deterioration of the transparent conductor over time. Here, the film having a high barrier property (barrier layer) is usually formed by a sputtering method, an evaporation method using ion assist, or the like. According to these methods, the material can collide with the film formation surface at high speed, and a dense film having a high barrier property can be obtained. On the other hand, the transparent metal film is very thin (for example, 15 nm or less). Therefore, when a barrier layer is formed on the transparent metal film by the above method, the transparent metal film is scraped, and the surface electrical resistance of the transparent conductor is increased or the light transmittance is decreased. Further, when the surface of the transparent metal film becomes rough during the formation of the barrier layer, localized plasmon absorption increases and the light transmittance of the transparent conductor decreases.

  On the other hand, in the transparent conductor of the present invention, the intermediate layer 4 is disposed on the transparent metal film 3. That is, the transparent metal film 3 is protected by the intermediate layer 4. The intermediate layer 4 is a layer having a lower packing density than the barrier layer 5; it can be a layer formed under relatively mild conditions. Therefore, the transparent metal film 3 is not easily damaged when the intermediate layer 4 is formed or when the barrier layer 5 is formed, and the surface electrical resistance of the transparent conductor is sufficiently low. Further, local plasmon absorption of the transparent metal film is hardly increased.

  Furthermore, in the transparent conductor of the present invention, the high refractive index layer 2 includes a material having a refractive index higher than the refractive index of light of the transparent substrate 1. Further, at least one of the intermediate layer 4 and the barrier layer 5 includes a material having a refractive index higher than the refractive index of light of the transparent substrate 1. That is, layers having a relatively high refractive index (high refractive index layer 2, intermediate layer 4 and / or barrier layer 5) are disposed on both surfaces of the transparent metal film 3. Since these layers adjust the optical admittance of the transparent conductor, the light transmittance of the transparent conductor is increased.

1.1) Configuration of Transparent Conductor a) Transparent Substrate The transparent substrate included in the transparent conductor can be the same as the transparent substrate of various display devices. The transparent substrate is a glass substrate, cellulose ester resin (for example, triacetyl cellulose, diacetyl cellulose, acetylpropionyl cellulose, etc.), polycarbonate resin (for example, Panlite, Multilon (both manufactured by Teijin Ltd.)), cycloolefin resin (for example, Zeonor) (Nippon Zeon Co., Ltd.), Arton (JSR Co., Ltd.), Appel (Mitsui Chemicals Co., Ltd.), acrylic resin (for example, polymethyl methacrylate, "Acrylite (Mitsubishi Rayon Co., Ltd.), Sumipex (Sumitomo Chemical Co., Ltd.)") , Polyimide, phenol resin, epoxy resin, polyphenylene ether (PPE) resin, polyester resin (eg, polyethylene terephthalate, polyethylene naphthalate), polyether sulfone, ABS (acrylonitrile, butadiene, styrene) / AS (acrylonitrile / styrene) resin, MBS (methyl methacrylate / butadiene / styrene) resin, polystyrene, methacrylic resin, polyvinyl alcohol / EVOH (ethylene vinyl alcohol resin), styrene block copolymer resin, etc. sell. When the transparent substrate is a transparent resin film, the film may contain two or more kinds of resins.

  From the viewpoint of transparency, the transparent substrate is a glass substrate or triacetyl cellulose, phenol resin, epoxy resin, polyphenylene ether (PPE) resin, polyether sulfone, ABS (acrylonitrile / butadiene / styrene) / AS (acrylonitrile / styrene) resin. A film made of MBS (methyl methacrylate / butadiene / styrene) resin, polystyrene, methacrylic resin, polyvinyl alcohol / EVOH (ethylene vinyl alcohol resin), or styrene block copolymer resin is preferable.

  The transparent substrate preferably has high transparency to visible light; the average transmittance of light having a wavelength of 450 to 800 nm is preferably 70% or more, more preferably 80% or more, and 85% or more. More preferably. When the average light transmittance of the transparent substrate is 70% or more, the light transmittance of the transparent conductor tends to increase. Moreover, it is preferable that the average absorption factor of the light with a wavelength of 450-800 nm of a transparent substrate is 10% or less, More preferably, it is 5% or less, More preferably, it is 3% or less.

  The average transmittance is measured by making light incident from an angle inclined by 5 ° with respect to the normal line of the surface of the transparent substrate. On the other hand, the average absorptance is calculated as average absorptivity = 100− (average transmissivity + average reflectivity) by making light incident from the same angle as the average transmissivity and measuring the average reflectivity of the transparent substrate. Average transmittance and average reflectance are measured with a spectrophotometer.

  The refractive index of light having a wavelength of 570 nm of the transparent substrate is preferably 1.40 to 1.95, more preferably 1.45 to 1.75, and still more preferably 1.45 to 1.70. The refractive index of the transparent substrate is usually determined by the material of the transparent substrate. The refractive index of the transparent substrate is measured with an ellipsometer.

  It is preferable that the haze value of a transparent substrate is 0.01-2.5, More preferably, it is 0.1-1.2. The haze value of a transparent conductor can be suppressed as the haze value of a transparent substrate is 2.5 or less. The haze value is measured with a haze meter.

  The thickness of the transparent substrate is preferably 1 μm to 20 mm, more preferably 10 μm to 2 mm. When the thickness of the transparent substrate is 1 μm or more, the strength of the transparent substrate is increased, and it is difficult to break or tear when the high refractive index layer is produced. On the other hand, when the thickness of the transparent substrate is 20 mm or less, the flexibility of the transparent conductor is sufficient, and the thickness of the device using the transparent conductor can be reduced. Moreover, the apparatus using a transparent conductor can also be reduced in weight.

b) High Refractive Index Layer The high refractive index layer is a layer that adjusts the optical admittance of the transparent conductor. The high refractive index layer includes a dielectric material or an oxide semiconductor material having a refractive index higher than that of light having a wavelength of 570 nm of the transparent substrate.

  The refractive index of light having a wavelength of 570 nm of the dielectric material or oxide semiconductor material contained in the high refractive index layer is preferably 0.1 to 1.1 larger than the refractive index of light having a wavelength of 570 nm of the transparent substrate. More preferably, it is 4 to 1.0 larger. The specific refractive index of the dielectric material or the oxide semiconductor material is preferably larger than 1.5, more preferably 1.7 to 2.5, and still more preferably 1.8 to 2.5. is there. When the refractive index of the material included in the high refractive index layer is greater than 1.5, the optical admittance of the transparent conductor is easily adjusted sufficiently. The refractive index of the high refractive index layer is adjusted by the refractive index of the material of the high refractive index layer and the packing density (film density) of the high refractive index layer.

  The packing density of the high refractive index layer is preferably 0.95 or more, more preferably 1 to 1.2, and still more preferably 1.05 to 1.2. The higher the packing density, the higher the refractive index of the high refractive index layer. The packing density is specified by the following method.

  (I) On a substrate made of BK7 (φ (diameter) = 30 mm t (thickness) = 2 mm) manufactured by SCHOTT GLASS, only the high refractive index layer is formed, and the spectral reflectance of the high refractive index layer is measured. On the other hand, the theoretical value of the spectral reflectance of the layer made of the same material as the high refractive index layer is calculated by (ii) thin film calculation software (Essential Macleod). Then, the packing density of the high refractive index layer is specified by comparing the theoretical value of the spectral reflectance calculated in (ii) with the spectral reflectance measured in (i).

The dielectric material or oxide semiconductor material contained in the high refractive index layer is preferably a metal oxide or metal sulfide. Examples of metal oxides or metal sulfides include TiO ₂ , ITO (indium tin oxide), ZnO, ZnS, Nb ₂ O ₅ , ZrO ₂ , CeO ₂ , Ta ₂ O ₅ , Ti ₃ O ₅ , Ti ₄ O. ₇ , Ti ₂ O ₃ , TiO, SnO ₂ , La ₂ Ti ₂ O ₇ , IZO (indium oxide / zinc oxide), AZO (Al-doped ZnO), GZO (Ga-doped ZnO), ATO (Sb-doped SnO), ICO (Indium cerium oxide) and the like are included. The metal oxide or metal sulfide is preferably TiO ₂ , ITO, ZnO, ICO, Nb ₂ O ₅ or ZnS from the viewpoint of refractive index and productivity. The high refractive index layer may contain only one kind of the metal oxide or metal sulfide, or may contain two or more kinds.

  The thickness of the high refractive index layer is preferably 10 to 150 nm, more preferably 20 to 80 nm. When the thickness of the high refractive index layer is 10 nm or more, the optical admittance of the transparent conductor is easily adjusted sufficiently by the high refractive index layer. On the other hand, when the thickness of the high refractive index layer is 150 nm or less, the light transmittance of the transparent conductor is hardly lowered by the high refractive index layer. The thickness of the high refractive index layer is measured with an ellipsometer.

c) Transparent metal film The metal contained in the transparent metal film is not particularly limited as long as it is a highly conductive metal, and may be, for example, silver, copper, gold, platinum group, titanium, chromium, molybdenum or the like. The transparent metal film may contain only one kind of these metals or two or more kinds. From the viewpoint of low plasmon absorption and low reflectance, the transparent metal film is preferably made of silver or an alloy containing 90 at% or more of silver. When the transparent metal film is made of a silver alloy, the metal combined with silver can be zinc, gold, copper, palladium, aluminum, manganese, bismuth, neodymium, molybdenum, or the like. For example, when silver is combined with zinc, the sulfide resistance of the transparent metal film is increased. Combining silver with gold increases salt resistance (NaCl) resistance. In addition, when silver is combined with copper, oxidation resistance is enhanced.

  The plasmon absorption rate of the transparent metal film is preferably 10% or less over the wavelength range of 400 nm to 800 nm (over the entire range). The plasmon absorption rate of the transparent metal film is more preferably 7% or less, and further preferably 5% or less. If there is a region having a large plasmon absorption rate in a part of the wavelength of 400 nm to 800 nm, the transmitted light of the transparent conductor is easily colored.

The plasmon absorption rate at a wavelength of 400 nm to 800 nm of the transparent metal film is measured by the following procedure.
(I) A platinum palladium film is formed to a thickness of 0.1 nm on a glass substrate using a magnetron sputtering apparatus. The average thickness of platinum palladium is calculated from the film forming speed and the like of the manufacturer's nominal value of the sputtering apparatus. Thereafter, a film made of the same metal as the object to be measured is formed on the substrate on which platinum palladium is adhered by a vapor deposition machine to a thickness of 20 nm.

  (Ii) Then, measurement light is incident from an angle inclined by 5 ° with respect to the normal line of the surface of the obtained metal film, and the transmittance and reflectance of the metal film are measured. Then, from the transmittance and reflectance at each wavelength, absorptivity = 100− (transmittance + reflectance) is calculated and used as reference data. The transmittance and reflectance are measured with a spectrophotometer.

  (Iii) Subsequently, the transmittance and reflectance of the transparent metal film to be measured are similarly measured. Then, the reference data is subtracted from the obtained absorption rate, and the calculated value is defined as the plasmon absorption rate.

  The thickness of the transparent metal film is 5 to 15 nm, preferably 3 to 13 nm, and more preferably 7 to 12 nm. When the thickness of the transparent metal film is 15 nm or less, the original reflection of the metal constituting the transparent metal film hardly occurs. Furthermore, when the thickness of the transparent metal film is 15 nm or less, as will be described later, the optical admittance of the transparent conductor is easily adjusted. The thickness of the transparent metal film is measured with an ellipsometer.

d) Intermediate layer The intermediate layer is a layer disposed between the above-described transparent metal film and a barrier layer described later, and is a layer that protects the transparent metal film from an impact during the formation of the barrier layer. The packing density of the intermediate layer is lower than the packing density of the barrier layer described later. In general, a film having a low packing density is formed under relatively mild conditions. Therefore, if the packing density of the intermediate layer is low, the transparent metal film is not easily damaged during the formation of the intermediate layer.

  The packing density of the intermediate layer may be a value lower than the packing density of the barrier layer, but the specific packing density is preferably 1.05 or less, more preferably 0.97 or less, and still more preferably. 0.90 to 0.97. The method for specifying the packing density of the intermediate layer may be the same as the method for specifying the packing density of the high refractive index layer described above.

  The intermediate layer includes a dielectric material or an oxide semiconductor material. The refractive index of the dielectric material or oxide semiconductor material is not particularly limited, and may be higher than the refractive index of the transparent substrate or lower than the refractive index of the transparent substrate.

  When the refractive index of light having a wavelength of 570 nm of the dielectric material or oxide semiconductor material contained in the intermediate layer is lower than the refractive index of light having a wavelength of 570 nm of the transparent substrate, the intermediate layer (hereinafter referred to as “low refractive index intermediate layer”) Plasmon absorption of the transparent metal film is suppressed. The reason is as follows.

上記式に基づけば、中間層の屈折率が低ければ低いほど、局在プラズモン吸収断面積が小さくなる。つまり、プラズモン吸収が抑制される。Assuming that the transparent metal film is composed of metal microspheres, the localized plasmon absorption cross section C _abs is expressed by the following equation.

Based on the above equation, the lower the refractive index of the intermediate layer, the smaller the localized plasmon absorption cross section. That is, plasmon absorption is suppressed.

  The specific refractive index of the dielectric material or oxide semiconductor material contained in the low refractive index intermediate layer is preferably less than 1.8, more preferably 1.30 to 1.6, and particularly preferably 1. .35 to 1.5. The refractive index of the low refractive index intermediate layer is mainly adjusted by the refractive index of the material of the low refractive index intermediate layer and the packing density of the low refractive index intermediate layer.

The dielectric material or oxide semiconductor material contained in the low refractive index intermediate layer is magnesium fluoride (MgF ₂ ), SiO ₂ , AlF ₃ , CaF ₂ , CeF ₃ , CdF ₃ , LaF ₃ , LiF, NaF, NdF _3. , YF ₃ , YbF ₃ , Ga ₂ O ₃ , LaAlO ₃ , Na ₃ AlF ₆ , Al ₂ O ₃ , MgO, and ThO ₂ . Dielectric material or an oxide semiconductor material is inter _alia, is _{MgF 2, SiO 2, CaF 2} , CeF 3, LaF 3, LiF, NaF, NdF 3, Na 3 AlF 6, Al 2 O 3, MgO or ThO _2, In view of low refractive index, MgF ₂ and SiO ₂ are particularly preferable. Only one of these materials may be included in the low refractive index intermediate layer, or two or more of these materials may be included.

  The dielectric material or oxide semiconductor material contained in the low refractive index intermediate layer is preferably an oxide of a metal having an atomic number of 31 or less from the viewpoint of not damaging the transparent metal film.

  The thickness of the low refractive index intermediate layer is preferably a thickness that does not significantly affect the optical admittance of the transparent conductor. Specifically, the thickness is preferably 1 to 30 nm, more preferably 3 to 15 nm, and still more preferably 7 to 12 nm. When the thickness of the low refractive index intermediate layer is 1 nm or more, the transparent metal film is sufficiently protected from impact during the formation of the barrier layer. On the other hand, when the thickness of the low refractive index intermediate layer is 30 nm or less, the optical admittance of the transparent conductor is not greatly affected. The thickness of the low refractive index intermediate layer is measured with an ellipsometer or the like.

  On the other hand, when the refractive index of light having a wavelength of 570 nm of the dielectric material or oxide semiconductor material contained in the intermediate layer is higher than the refractive index of light having a wavelength of 570 nm of the transparent substrate, the intermediate layer (hereinafter referred to as “high refractive index intermediate”). As will be described later, the optical admittance of the transparent conductor is adjusted.

  The refractive index of light having a wavelength of 570 nm of the dielectric material or oxide semiconductor material contained in the high refractive index intermediate layer is preferably 0.1 to 1.1 larger than the refractive index of light having a wavelength of 570 nm of the transparent substrate described above. 0.4 to 1.0 is more preferable. The specific refractive index of the dielectric material or oxide semiconductor material contained in the high refractive index intermediate layer is preferably greater than 1.5, more preferably 1.6 to 2.5, and still more preferably 1.8 to 2.5. When the refractive index of the material contained in the high refractive index intermediate layer is larger than 1.5, the optical admittance is sufficiently adjusted by the high refractive index intermediate layer. The refractive index of the high refractive index intermediate layer is mainly adjusted by the refractive index of the material of the high refractive index intermediate layer and the packing density of the high refractive index intermediate layer.

  Here, the dielectric material or the oxide semiconductor material included in the high refractive index intermediate layer may be the same as the dielectric material or the oxide semiconductor material included in the high refractive index layer.

  The thickness of the high refractive index intermediate layer is appropriately adjusted based on the optical admittance of the transparent conductor. The thickness of the high refractive index intermediate layer is preferably 10 to 150 nm, more preferably 20 to 80 nm. When the thickness of the high refractive index intermediate layer is 10 nm or more, the transparent metal film is sufficiently protected from an impact at the time of forming the barrier layer. Furthermore, the optical admittance of the transparent conductor is sufficiently adjusted. On the other hand, when the thickness of the high refractive index intermediate layer is 150 nm or less, the light transmittance of the transparent conductor is hardly lowered by the high refractive index intermediate layer. The thickness of the high refractive index intermediate layer is measured with an ellipsometer or the like.

e) Barrier layer The barrier layer is a layer that protects the transparent metal film from moisture outside the transparent conductor; it is a layer having a higher packing density than the aforementioned intermediate layer. The packing density of the barrier layer only needs to be higher than the packing density of the intermediate layer, but is preferably 0.07 or more, more preferably 0.1 or more higher than the packing density of the intermediate layer. The higher the packing density of the barrier layer, the denser the barrier layer and the higher the barrier property of the barrier layer. The specific packing density of the barrier layer is preferably 0.98 or more, more preferably 1 to 1.20. When the packing density of the barrier layer is 0.98 or more, sufficient barrier properties are obtained, and corrosion of the transparent metal film is suppressed. The packing density of the barrier layer is adjusted by the method for forming the barrier layer. Further, the method for specifying the packing density may be the same as the method for specifying the packing density of the high refractive index layer.

On the other hand, the water permeability of the barrier layer is preferably 450 g / m ² / day or less, and more preferably 300 g / m ² / day or less. When the water permeability is 450 g / m ² / day or less, the corrosion of the transparent metal film is sufficiently suppressed. The water permeability of the barrier layer is the same as that of the barrier layer, and only the barrier layer is formed on a TAC film (100 mm × 100 mm t (thickness) = 40 μm). It is specified by measuring with a rate measuring device. The water permeability of the barrier layer is adjusted by the type of material constituting the barrier layer and the method for forming the barrier layer.

  The barrier layer includes a dielectric material or an oxide semiconductor material. The refractive index of the dielectric material or oxide semiconductor material is not particularly limited, and may be higher than the refractive index of the transparent substrate or lower than the refractive index of the transparent substrate.

  When the refractive index of light having a wavelength of 570 nm of the dielectric material or oxide semiconductor material contained in the barrier layer is higher than the refractive index of light having a wavelength of 570 nm of the transparent substrate, the barrier layer (hereinafter referred to as “high refractive index barrier layer”) As will be described later, the optical admittance of the transparent conductor is adjusted.

  The refractive index of light having a wavelength of 570 nm of the dielectric material or oxide semiconductor material contained in the high refractive index barrier layer is preferably 0.1 to 1.1 greater than the refractive index of light having a wavelength of 570 nm of the transparent substrate described above. 0.4 to 1.0 is more preferable. The specific refractive index of the dielectric material or oxide semiconductor material contained in the high refractive index barrier layer is preferably greater than 1.5, more preferably 1.6 to 2.5, and still more preferably 1.8 to 2.5. When the refractive index of the material contained in the high refractive index barrier layer is greater than 1.5, the optical admittance of the transparent conductor is sufficiently adjusted by the high refractive barrier layer. The refractive index of the high refractive index barrier layer is mainly adjusted by the refractive index of the material of the high refractive index barrier layer and the packing density of the high refractive index barrier layer.

The dielectric material or oxide semiconductor material contained in the high refractive index barrier layer is preferably a metal oxide. Examples of metal oxides include HfO ₂ , Y ₂ O ₃ , La ₂ O ₃ , LaAlO ₃ , PrTiO ₃ , SiO _x N _y (x> 0, y> 0), TiO ₂ , ITO (indium tin oxide) , ZnO, ZnS, Nb ₂ O ₅ , ZrO ₂ , CeO ₂ , Ta ₂ O ₅ , Ti ₃ O ₅ , Ti ₄ O ₇ , Ti ₂ O ₃ , TiO, SnO ₂ , La ₂ Ti ₂ O ₇ , IZO, AZO (Al-doped ZnO), GZO (Ga-doped ZnO), ATO (Sb-doped SnO), ICO (indium cerium oxide) and the like are included. The high refractive index barrier layer may contain only one kind of these metal oxides, or may contain two or more kinds. Among these, the material of the high refractive index barrier layer is preferably Nb ₂ O ₅ , ZnO, TiO ₂ , ITO, or ICO. The material of the high refractive index barrier layer may be the same as the material of the intermediate layer described above.

  The thickness of the high refractive index barrier layer is appropriately adjusted based on the water permeability of the high refractive index barrier layer and the optical admittance of the transparent conductor. The thickness of the high refractive index barrier layer is preferably 10 to 150 nm, more preferably 20 to 80 nm. When the thickness of the high refractive index barrier layer is 10 nm or more, corrosion of the transparent metal film is sufficiently suppressed. Further, the optical admittance of the transparent conductor is sufficiently adjusted by the high refractive index barrier layer. The thickness of the high refractive index barrier layer is measured with an ellipsometer or the like.

  On the other hand, when the refractive index of light having a wavelength of 570 nm of the dielectric material or oxide semiconductor material included in the barrier layer is lower than the refractive index of light having a wavelength of 570 nm of the transparent substrate, the barrier layer (hereinafter referred to as “low refractive index barrier”). The optical admittance of the transparent conductor is finely adjusted.

  The specific refractive index of light having a wavelength of 570 nm of the dielectric material or oxide semiconductor material contained in the low refractive index barrier layer is preferably 1.3 or more and less than 1.8, more preferably 1.35 to 1.35. 1.6, more preferably 1.35 to 1.5. When the refractive index of the material contained in the low refractive index barrier layer is 1.35 to 1.5, the optical admittance of the transparent conductor is easily finely adjusted. The refractive index of the low refractive index barrier layer is adjusted by the material of the low refractive index barrier layer and its packing density.

The dielectric material or oxide semiconductor material included in the low refractive index barrier layer may be the same as the material included in the low refractive index intermediate layer described above. From the viewpoint of the barrier property of the low refractive index barrier layer, the dielectric material or the oxide semiconductor material is preferably SiO ₂ , Al ₂ O ₃ , or MgF ₂ .

  The thickness of the low refractive index barrier layer is preferably 10 to 150 nm, more preferably 10 to 60 nm, from the viewpoint of water permeability of the low refractive index barrier layer. When the thickness of the low refractive index barrier layer is 10 nm or more, the corrosion of the transparent metal film is sufficiently suppressed. The thickness of the barrier layer is measured with an ellipsometer or the like.

f) Other layers The transparent conductor of the present invention may contain other layers in addition to the above-mentioned transparent substrate, high refractive index layer, transparent metal film, intermediate layer, and barrier layer. The other layers may be any layers as long as they do not affect the light transmittance of the transparent conductor. The thickness of the other layers is preferably 15 nm or less, more preferably 10 nm or less.

g) Layer Configuration of Transparent Conductor As described above, the transparent conductor of the present invention includes a transparent substrate, a high refractive index layer, a transparent metal film, an intermediate layer, and a barrier layer. Here, the intermediate layer may be a low refractive index intermediate layer including a material having a lower refractive index than that of the transparent substrate, or a high refractive index intermediate layer including a material having a higher refractive index than that of the transparent substrate. Meanwhile, the barrier layer may be a low refractive index barrier layer having a refractive index lower than that of the transparent substrate or a high refractive index barrier layer having a refractive index higher than that of the transparent substrate. At least one of the intermediate layer and the barrier layer has a refractive index higher than that of the transparent substrate.

That is, the layer structure of the transparent conductor of the present invention can be the following three structures.
(I) Transparent substrate / high refractive index layer / transparent metal film / low refractive index intermediate layer / high refractive index barrier layer (ii) Transparent substrate / high refractive index layer / transparent metal film / high refractive index intermediate layer / high refractive index Barrier layer (iii) Transparent substrate / High refractive index layer / Transparent metal film / High refractive index intermediate layer / Low refractive index barrier layer

  Among the above three configurations, the configuration (i) is preferable. In the configuration of (i), not only the optical admittance of the transparent conductor is adjusted by the high refractive index layer and the high refractive index barrier layer; the plasmon absorption of the transparent metal film is suppressed by the low refractive index intermediate layer. . Therefore, the light absorption of the transparent conductor is sufficiently suppressed, and the light transmittance of the transparent conductor is easily increased.

  On the other hand, in the configuration (ii), the optical admittance of the transparent conductor is adjusted by the high refractive index layer, the high refractive index intermediate layer, and the high refractive index barrier layer. In the configuration (iii), the optical admittance of the transparent conductor is mainly adjusted by the high refractive index layer and the high refractive index intermediate layer.

  In the transparent conductor of the present invention, the transparent metal film may be patterned into a predetermined shape. The shape of the pattern is appropriately selected according to the use of the transparent conductor. Examples of the pattern include a touch panel wiring pattern and the like.

2. Method for Producing Transparent Conductor The method for producing the transparent conductor described above includes at least the following three steps.
(I) The process of preparing the laminated body by which the transparent substrate, the high refractive index layer, and the transparent metal film were laminated | stacked (ii) The process of forming an intermediate | middle layer on a transparent metal film (iii) On an intermediate | middle layer, Step of forming a barrier layer

  As described above, when a dense barrier layer having a high film density is formed directly on the transparent metal film, the transparent metal film may be scraped off when the barrier layer is formed. On the other hand, in this invention, after forming an intermediate | middle layer on a transparent metal film, a barrier layer is formed into a film. Therefore, the transparent metal film is not damaged, and a transparent conductor having a sufficiently low surface resistance can be obtained.

2.1) Laminate Preparation Step First, a laminate in which the above-described high refractive index layer and transparent metal film are laminated on a transparent substrate is prepared. Specifically, the above-described high refractive index layer is formed on a transparent substrate, and then a transparent metal film is laminated. The film forming method of the high refractive index layer is not particularly limited, and may be a general gas phase film forming method such as a vacuum deposition method, a sputtering method, an ion plating method, a plasma CVD method, a thermal CVD method, or the like. From the viewpoint of increasing the refractive index of the resulting high refractive index layer and increasing the film forming efficiency, the film forming method of the high refractive index layer is preferably an electron beam vapor deposition method or a DC sputtering method using ion assist together. .

Subsequently, the above-described transparent metal film is formed on the high refractive index layer. The method for forming the transparent metal film may be a general vapor deposition method. As described above, in order to obtain a film having a thickness of 15 nm or less and low plasmon absorption, the following two methods are used. It is preferable to form a film through steps.
(A) Step of forming a growth nucleus on the high refractive index layer (b) Step of forming a transparent metal film on the high refractive index layer

  When a transparent metal film is formed on a high refractive index layer by a general vapor deposition method, atoms attached on the high refractive index layer migrate (move) and atoms gather together in the initial stage of film formation. To form a lump (island structure). And a film grows clinging to this lump. Therefore, in the film at the initial stage of film formation, there is a gap between the lumps and it is not conductive. When a lump further grows from this state and the thickness becomes about 15 μm, a part of the lump is connected and barely conducted. However, the surface of the film is difficult to smooth and plasmon absorption is likely to occur.

  On the other hand, if the growth nuclei are formed in advance in the (a) growth nucleus formation step, the material of the transparent metal film is difficult to migrate on the high refractive index layer. Further, the interval between the growth nuclei is narrower than the interval between the lumps formed by migration of atoms. Therefore, when the film grows starting from this growth nucleus, a flat film is likely to be formed even if the thickness is small. That is, even if the thickness is small, conduction is obtained and a transparent metal film in which plasmon absorption does not occur is obtained.

(A) Growth nucleus formation step Growth nuclei for forming a transparent metal film are formed on the high refractive index layer. There are the following two types of growth nucleus formation methods.
(I) A method in which a metal thin film having a thickness of 3 nm or less is formed on a high refractive index layer by sputtering or vapor deposition, and this is used as a growth nucleus. (Ii) A metal layer is formed on the high refractive index layer. A method of dry etching a metal layer and using the remaining metal thin film as a growth nucleus

  When forming growth nuclei by the method (i), a thin film (growth nuclei) is formed of a metal that is difficult to migrate (move) on the high refractive index layer. Examples of metals that can be growth nuclei include gold, platinum group, cobalt, nickel, molybdenum, titanium, aluminum, chromium, nickel, or alloys thereof. A growth nucleus may be formed by using only one of these, or a growth nucleus may be formed by combining two or more kinds. Among these, it is preferable to form a growth nucleus with platinum palladium, palladium, titanium, molybdenum or aluminum. Platinum palladium or palladium is difficult to migrate on the high refractive index layer, has a high affinity with the metal constituting the transparent metal film, and provides a dense and fine growth nucleus. The ratio of palladium contained in platinum palladium is preferably 10% by mass or more, and more preferably 20% by mass or more. When the proportion of palladium is 10% by mass or more, dense and fine growth nuclei are easily obtained, and a smooth transparent metal film is easily obtained.

  In the case where a thin film made of titanium or aluminum is used as a growth nucleus, if the thin film (growth nucleus) is finely broken by ion assist or the like, a fine and fine growth nucleus similar to platinum palladium or palladium can be easily obtained.

  The thin film (growth nucleus) made of the metal is preferably formed by sputtering or vapor deposition. The average thickness of the thin film (growth nucleus) is preferably 3 nm or less, more preferably 0.5 nm or less, still more preferably a monoatomic film, and particularly preferably metal atoms are attached to be separated from each other. It is a membrane. The average thickness of the thin film (growth nucleus) is adjusted by the film forming speed and the film forming time.

  Examples of the sputtering method include an ion beam sputtering method, a magnetron sputtering method, a reactive sputtering method, a bipolar sputtering method, and a bias sputtering method. The sputtering time is appropriately selected according to the average thickness of the thin film (growth nucleus) to be formed and the film formation speed. The sputter deposition rate is preferably 0.1 to 15 Å / second, more preferably 0.1 to 7 Å / second.

  On the other hand, examples of the vapor deposition method include a vacuum vapor deposition method, an electron beam vapor deposition method, an ion plating method, and an ion beam vapor deposition method. The deposition time is appropriately selected according to the thin film to be formed (growth nuclei) and the deposition rate. The deposition rate is preferably 0.1 to 15 Å / second, more preferably 0.1 to 7 Å / second.

  When forming growth nuclei by the method (ii), a metal layer is formed on the high refractive index layer, and this metal layer is dry-etched to a desired thickness. The dry etching referred to in the present invention includes reactive gas etching in which etching is performed by a chemical reaction and a method of polishing with lens paper or the like, but etching that involves physical collision of etching gas, ions, radicals, and the like. A method is preferred. When the metal layer is etched by an etching method involving physical collision, a uniform metal thin film (growth nucleus) is easily formed on the high refractive index layer.

  The type of the metal thin film (growth nucleus) is not particularly limited as long as it is a metal having high affinity with the metal contained in the transparent metal film. The metal contained in the transparent metal film may be the same or different; examples include silver, gold, platinum group, titanium and aluminum.

  The method for forming the metal layer is not particularly limited, and may be a dry deposition method such as a vacuum deposition method, a sputtering method, an ion plating method, a plasma CVD method, a thermal CVD method, or a wet deposition method such as a plating method. . The average thickness of the metal layer to be formed is preferably 3 to 15 nm, more preferably 5 to 10 nm. When the average thickness of the metal layer is 3 nm or more, sufficient growth nuclei are easily obtained.

  The metal layer dry etching method is preferably an etching method involving physical collision as described above, and may be ion beam etching, reverse sputter etching, plasma etching, or the like. In particular, ion beam etching is particularly preferable from the viewpoint that desired unevenness can be easily formed on the etched thin film (growth nucleus).

  The average thickness of the thin film (growth nucleus) obtained by dry etching of the metal layer is preferably 3 nm or less, more preferably 2 nm or less, still more preferably 0.01 to 1 nm, and particularly preferably 0. 01-0.2 nm. When the thickness of the thin film (growth nucleus) is 3 nm or less, a thin and smooth transparent metal film can be easily obtained. Furthermore, the thickness of the transparent metal film formed starting from this growth nucleus tends to be thin. The average thickness of the growth nucleus is obtained from the difference between the thickness of the metal film and the etching thickness of the metal film. The etching thickness of the metal film is the product of the etching rate and the etching time. The etching rate is obtained from the time until a 50 nm thick metal layer separately prepared on a glass substrate is etched under the same conditions and the light transmittance after the etching becomes equivalent to that of the glass substrate (approximately 0 nm thickness). The average thickness of the growth nucleus is adjusted by the time for dry etching.

(B) Transparent metal film formation step On the high refractive index layer on which the above-described growth nuclei are formed, a metal is laminated by a general vapor deposition method to form a transparent metal film. The type of vapor deposition method is not particularly limited, and may be, for example, a vacuum deposition method, a sputtering method, an ion plating method, a plasma CVD method, a thermal CVD method, or the like. Among these, the vacuum deposition method is preferable. According to the vacuum deposition method, it is easy to obtain a transparent metal film having a uniform thickness and a desired thickness.

2.2) Intermediate layer film forming step The above-described intermediate layer is formed on the transparent metal film. As described above, when the material collides with the transparent metal film at a high speed during the formation of the intermediate layer, the transparent metal film is easily scraped. In addition, when the molecular weight of the material constituting the intermediate layer is large, the transparent metal film is easily scraped; when the intermediate layer is a metal oxide having a large atomic number, the transparent metal film is very easily scraped. Become.

  Therefore, when the atomic number of the metal included in the material constituting the intermediate layer is large; specifically, when the atomic number of the metal is more than 31, the vacuum deposition method, the RF sputtering method, the outer edge of the target It is preferable to form the intermediate layer by an opposed target type sputtering method (sputtering method described in JP 2013-48143 A) or the like in which a permanent magnet is disposed on the surface. When the intermediate layer is formed by RF sputtering or target sputtering, it is preferable to introduce an inert gas, and it is more preferable to introduce nitrogen gas. When an inert gas is introduced, the transparent metal film becomes difficult to be cut. The introduction amount of the inert gas is preferably 0.5 sccm or more.

  On the other hand, when the atomic number of the metal contained in the material constituting the intermediate layer is small; specifically, when the atomic number of the metal is 31 or less, the method for forming the intermediate layer is not particularly limited. The method for forming the intermediate layer may be a general vapor deposition method such as a vacuum deposition method, a sputtering method, an ion plating method, a plasma CVD method, a thermal CVD method, or the like. Among these, the DC sputtering method is preferable from the viewpoint of film formation efficiency.

2.3) Barrier layer deposition step The barrier layer described above is deposited on the intermediate layer. The barrier layer can be formed by sputtering or ion-assisted deposition. According to these film forming methods, the packing density of the obtained barrier layer can be increased, and the barrier layer becomes a dense film.

  Examples of the sputtering method include a DC sputtering method, an RF sputtering method, a magnetron sputtering method, and an ion beam sputtering method. The DC sputtering method is particularly preferable from the viewpoint that the material of the barrier layer can collide with the film formation surface (intermediate layer) at a high speed and the resulting barrier layer becomes dense. In addition, the barrier layer may be reverse-sputtered simultaneously with the formation of the barrier layer or after part of the barrier layer is formed. By reverse sputtering, the resulting barrier layer becomes denser and the barrier properties of the barrier layer are further enhanced.

  On the other hand, film formation by ion-assisted vapor deposition is performed by a general vapor deposition apparatus and ion beam apparatus. The ion species used for the ion beam may be an inert gas such as argon or helium, or may be a reactive gas such as oxygen or nitrogen. When the ionic species is a reactive gas, the film can be formed while oxidizing or nitriding the material.

3. Regarding Optical Admittance of Transparent Conductor As described above, in the transparent conductor of the present invention, the transparent metal film is sandwiched between layers having a high refractive index (high refractive index layer, intermediate layer and / or barrier layer). . As a result, the optical admittance of the transparent conductor is adjusted, and the light transmittance of the transparent conductor is increased.

上記の式に基づけば、｜Ｙ_ｅｎｖ−Ｙ_Ｅ｜が０に近い程、透明導電体の表面の反射率Ｒが低くなる。Here, the reflectance R of the surface of the transparent conductor (the surface opposite to the transparent substrate in the transparent conductor) is expressed by the optical admittance Y _{env of the} medium on which light is incident and the equivalent admittance Y _E of the surface of the transparent conductor. Determined from. Here, the surface of the transparent conductor means a member made of an organic resin disposed on the transparent conductor or a surface in contact with the environment. The medium on which light is incident refers to a member or environment through which light incident on the transparent conductor passes immediately before incident; a member or environment made of an organic resin. The relationship between the optical admittance Y _{env of the} medium and the equivalent admittance Y _E of the surface of the transparent conductor is expressed by the following equation.

Based on the above formula, the closer the value | Y _env −Y _E | is to 0, the lower the reflectance R of the surface of the transparent conductor.

The optical admittance Y _env of the medium is obtained from the ratio (H / E) of the electric field strength and the magnetic field strength, and is the same as the refractive index n _{env of the} medium. On the other hand, the equivalent admittance Y _E is determined from the optical admittance Y of the layers constituting the transparent conductor. For example, when the transparent conductor composed of one is equivalent admittance Y _E of the transparent conductor is equal to the of the layer optical admittance Y (refractive index).

On the other hand, when the transparent conductor is a laminate, the optical admittance Y _x (E _x H _x ) of the laminate from the first layer to the x layer is the laminate from the first layer to the (x−1) layer. It is represented by the product of the optical admittance Y _x-1 (E _x-1 H _x-1 ) of the body and a specific matrix; specifically, it is obtained by the following formula (1) or formula (2).

When the x-th layer is a layer made of a dielectric material or an oxide semiconductor material

・ When the xth layer is an ideal metal layer

When the x-th layer is the outermost layer, the optical admittance Y _x (E _x H _x ) of the laminate from the transparent substrate to the outermost layer becomes the equivalent admittance Y _E of the transparent conductor.

FIG. 2A shows a transparent conductor (transparent substrate (white plate) / high refractive index layer (TiO ₂ ) / transparent metal film (Ag) / intermediate layer (TiO ₂ ) / barrier layer (TiO ₂ ) of Example 1 described later. The admittance locus | trajectory of wavelength 570nm of the transparent conductor provided) is shown. The horizontal axis of the graph is the real part when the optical admittance Y is represented by x + iy; that is, x in the formula, and the vertical axis is the imaginary part of the optical admittance; that is, y in the formula.

In Figure 2A, the final coordinates of the admittance locus is equivalent admittance Y _E. The distance between the coordinates (x _E , y _E ) of the equivalent admittance Y _E and the admittance coordinates (n _env , 0) (not shown) of the medium on which the light is incident becomes the reflectance R of the transparent conductor surface. Proportional. In the present invention, the distance ((x _E −n _env ) ² + (y _E ) between the coordinates (x _E , y _E ) of the equivalent admittance Y _E and the admittance coordinates (n _env , 0) of the medium on which light is incident. ² ) ^0.5 is preferably less than 0.5, more preferably 0.3 or less. If the distance is less than 0.5, the reflectance R of the transparent conductor surface is sufficiently small, and the light transmittance of the transparent conductor is likely to increase.

A transparent metal film generally has a large imaginary value of optical admittance. Therefore, when a transparent metal film is laminated directly on a transparent substrate, the admittance locus greatly moves in the negative direction of the vertical axis (imaginary part). FIG. 3A shows an admittance locus of a transparent conductor having a transparent substrate / transparent metal film / high refractive index layer in this order at a wavelength of 570 nm, and FIG. 3B shows an admittance of the transparent conductor having a wavelength of 450 nm, a wavelength of 570 nm, and a wavelength of 700 nm. Show the trajectory. As shown in FIG. 3A, when a transparent metal film is laminated directly on a transparent substrate, the admittance locus starts in the negative direction of the vertical axis (imaginary part) from the starting point of the admittance locus (the admittance coordinates (about 1.5,0) of the transparent substrate) The admittance locus moves greatly, and the absolute value of the imaginary part of the admittance coordinates becomes very large. When the absolute value of the imaginary part of the admittance coordinates increases, the equivalent admittance Y _E approaches the admittance coordinates (n _env , 0) of the medium on which light is incident even if a high refractive index layer is laminated on the transparent metal film. It becomes difficult.

Further, as shown in FIG. 3A, when a transparent metal film is directly laminated on a transparent substrate, the admittance locus is less likely to be line symmetric about the horizontal axis of the graph. If the admittance locus at a specific wavelength (570 nm in the present invention) is not line-symmetric about the horizontal axis of the graph, as shown in FIG. 3B, equivalent admittance Y _{E at} other wavelengths (for example, 450 nm and 700 nm) is obtained. The coordinates of are easy to shake greatly. Therefore, a wavelength region where the antireflection effect is not sufficient is likely to occur.

In contrast, when the transparent metal film is sandwiched between layers having a high refractive index (high refractive index layer and intermediate layer and / or barrier layer), a layer (high refractive index) disposed on one side of the transparent metal film. The coordinates of the imaginary part of the admittance locus greatly move in the positive direction. And even if an admittance locus | trajectory largely moves to the negative direction of an imaginary part by a transparent metal film, the absolute value of an imaginary part becomes difficult to become large. On the other hand, the layer (intermediate layer and / or barrier layer) disposed on the other side of the transparent metal film brings the equivalent admittance Y _E closer to the admittance coordinates (n _env , 0) of the medium on which light is incident.

In addition, when the transparent metal film is sandwiched between layers having a high refractive index (high refractive index layer, intermediate layer and / or barrier layer), the admittance locus tends to be line symmetric about the horizontal axis of the graph. As a result, not only of wavelength 570 nm, centered becomes axisymmetric horizontal axis of the graph also admittance locus of wavelength 400nm and the wavelength 700 nm, the coordinates of the equivalent admittance Y _E of each wavelength is approximately the same. That is, at any wavelength, the equivalent admittance Y _E is close to the admittance coordinates (n _env , 0) of the medium on which light is incident.

Here, in the transparent conductor of the present invention, the optical admittance at a wavelength of 570 nm on the surface of the transparent metal film on the high refractive index layer side is Y1 (= x ₁ + ii ₁ ), and the wavelength on the surface of the transparent metal film on the intermediate layer side When the optical admittance at 570 nm is Y2 (= x ₂ + iy ₂ ), it is preferable that one or both of x ₁ and x ₂ is 1.6 or more. either one of x ₁ and x ₂ are, increases light transmission of the transparent conductor If it is 1.6 or more. The reason will be described below.

上記関係式に基づけば、透明金属膜表面の光学アドミッタンスＹ１及びＹ２の実数部（ｘ_１及びｘ_２）が大きくなれば、電場強度Ｅが小さくなり、電場損失（光の吸収）が抑制される。すなわち、透明導電体の光透過性が十分に高まる。The following relational expression holds between the admittance Y at the interface of each layer and the electric field strength E existing in each layer.

Based on the above relational expression, if the real part (x ₁ and x ₂ ) of the optical admittances Y1 and Y2 on the surface of the transparent metal film is increased, the electric field strength E is decreased and the electric field loss (light absorption) is suppressed. . That is, the light transmittance of the transparent conductor is sufficiently increased.

The transparent conductor of the present invention, among the above-mentioned x ₁ and x _2, are either Meanwhile, or preferably both are 1.6 or more, more preferably 1.8 or more, more preferably 2.0 That's it. In particular, x ₁ is preferably 1.6 or more. The _{x 1} and _{x 2} is preferably 7.0 or less, more preferably 5.5 or less. x ₁ is the refractive index and the high refractive index layer is adjusted in such a thickness of the high refractive index layer. x ₂ is the refractive index of the values and the transparent metal film x _1, is adjusted by the thickness or the like of the transparent metal film. For example, when the refractive index of the high refractive index layer is high or when some extent thicker, the value of x ₁ and x ₂ tends to increase.

Further, the absolute value (| x ₁ −x ₂ |) of the difference between x ₁ and x ₂ is preferably 1.5 or less, more preferably 1.0 or less, and further preferably 0.8 or less. is there. In particular, when the admittance locus of the transparent metal film and the horizontal axis intersect at a coordinate Ycross (x _cross , 0), | x ₁ −x ₂ | / x _cross is preferably smaller than 0.5. Preferably it is 0.3 or less, More preferably, it is 0.2 or less.

As described above, admittance locus is preferably a center line of symmetry of the horizontal axis of the graph. For this purpose, a coordinate y ₁ of the imaginary part of the Y1, the coordinate y ₂ of the imaginary part of the Y2, y It is preferable to satisfy ₁ × y ₂ ≦ 0. Furthermore, | y ₁ + y ₂ | is preferably less than 0.8, more preferably 0.5 or less, and still more preferably 0.3 or less. If | y ₁ + y ₂ | is less than 0.8, the admittance trajectory tends to be line symmetric about the horizontal axis of the graph.

Further, in order to make the admittance locus line-symmetric with respect to the horizontal axis of the graph, it is preferable that y ₁ described above is sufficiently large. The value of the imaginary part of the optical admittance of the transparent metal film is large, and the admittance locus moves greatly in the direction of the vertical axis (imaginary part). Therefore, if y ₁ is too small, the absolute value of the imaginary part of the admittance coordinates becomes very large, admittance locus hardly become axisymmetric. y ₁ is preferably 0.2 or more, more preferably 0.3 to 1.5, and still more preferably 0.3 to 1.0. On the other hand, y ₂ described above is preferably −0.3 to −2.0, and more preferably −0.6 to −1.5.

4). About the physical property of a transparent conductor The average transmittance | permeability of the light with a wavelength of 450 nm-800 nm of the transparent conductor of this invention is 50% or more, More preferably, it is 80% or more, More preferably, it is 85% or more. On the other hand, the average reflectance of light having a wavelength of 500 nm to 700 nm of the transparent conductor is preferably 20% or less, more preferably 15% or less, and further preferably 10% or less. If the average transmittance of light having the above wavelength is 50% or more and the average reflectance is 20% or less, the transparent conductor can also be applied to uses where high transparency is required. The absorptance, average transmittance, and average reflectance are measured by allowing measurement light to enter the transparent conductor from an angle inclined by 5 ° with respect to the normal of the surface of the transparent conductor. The average transmittance and average reflectance are measured with a spectrophotometer.

  The luminous transmittance of the transparent conductor of the present invention is preferably 80% or more, more preferably 85% or more. The luminous transmittance is measured with a spectrophotometer (U4100; manufactured by Hitachi High-Technologies Corporation).

  On the other hand, the average absorptance of light having a wavelength of 400 nm to 800 nm is preferably 10% or less, preferably 8% or less, and more preferably 7% or less. Moreover, the maximum value of the absorptance of light with a wavelength of 400 nm to 800 nm is 15% or less, preferably 10% or less, and more preferably 9% or less. The light absorption rate of the transparent conductor can be reduced by suppressing the plasmon absorption rate of the transparent metal film and the light absorption rate of the material constituting each layer. The light absorptance of the transparent conductor is calculated based on the above-described transmittance and reflectance (absorbance = 100− (transmittance + reflectance)).

  The a * value and b * value in the L * a * b * color system of the transparent conductor are preferably within ± 30, more preferably within ± 5, and even more preferably within ± 3.0. Particularly preferably, it is within ± 2.0. If the a * value and b * value in the L * a * b * color system are within ± 30, the transparent conductor is observed as colorless and transparent. The a * value and b * value in the L * a * b * color system are measured with a spectrophotometer.

  The surface electrical resistance of the transparent conductor is preferably 50Ω / □ or less, more preferably 30Ω / □ or less. A transparent conductor having a surface electric resistance value of 50Ω / □ or less can be applied to a transparent conductive panel for a capacitive touch panel. The surface electrical resistance value of the transparent conductor is adjusted by the thickness of the transparent metal film and the like. The surface electrical resistance value of the transparent conductor is measured in accordance with, for example, JIS K7194, ASTM D257, and the like. It is also measured by a commercially available surface electrical resistivity meter.

The difference (haze degradation) between the haze value of the transparent conductor and the haze value _Hsub of the transparent substrate is preferably less than 0.9, more preferably 0.5 or less, and even more preferably 0.3 or less. It is. The difference between the haze value of the transparent conductor and the haze value _Hsub of the transparent substrate is an index indicating how much the transparency is impaired by the lamination of the high refractive index layer, the transparent metal film, the intermediate layer, and the barrier layer. . The haze value of the transparent conductor is measured with a haze meter.

5). Applications of transparent conductors The above-mentioned transparent conductors include various types of displays such as liquid crystal, plasma, organic electroluminescence, field emission, touch panels, mobile phones, electronic paper, various solar cells, various electroluminescent dimming elements, etc. It can be preferably used for a substrate of an optoelectronic device.

At this time, the surface of the transparent conductor (for example, the surface opposite to the transparent substrate) may be bonded to another member via an adhesive layer or the like. In this case, as described above, it is preferable admittance coordinates of the equivalent admittance Y _E of the surface of the transparent conductor and the admittance coordinates of the adhesive layer is closer. Thereby, reflection at the interface between the transparent conductor and the adhesive layer is suppressed.

On the other hand, when the surface of the transparent conductor is used in construction as contact with air, it is preferred that close to the admittance coordinates of the admittance coordinates and the air equivalent admittance Y _E of the surface of the transparent conductor. Thereby, reflection of the light on the transparent conductor surface is suppressed.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the scope of the present invention is not limited by this. In each example, the measurement of the thickness of the film and the measurement of the transparent metal film were performed by the following methods.

<Measurement method of film thickness>
The thickness of each layer is described in J. A. Woollam Co. Inc. It measured with the VB-250 type | mold VASE ellipsometer made from.

<Measurement method of plasmon absorption rate of transparent metal film>
The plasmon absorption rate of the transparent metal film was measured as follows. A platinum palladium film was formed on a transparent glass substrate by 0.2 s (0.1 nm) on the substrate using a magnetron sputtering apparatus (MSP-1S) manufactured by Vacuum Device Inc. The average thickness of platinum-palladium was calculated from the film formation rate at the manufacturer's nominal value of the sputtering apparatus. Thereafter, a silver film having a thickness of 20 nm was formed on a substrate on which platinum palladium was adhered using a BMC-800T vapor deposition machine manufactured by SYNCHRON. The resistance heating at this time was 210 A, and the film formation rate was 5 Å / s. The reflectance and transmittance of the obtained transparent metal film were measured and calculated as absorptivity = 100− (transmittance + reflectance). Assuming that this transparent metal film has no plasmon absorption, the plasmon absorption rate was measured by subtracting from the data obtained by measuring the absorption rate of the transparent metal film prepared in each example. The light transmittance and reflectance were measured with a spectrophotometer U4100 manufactured by Hitachi, Ltd.

[Example 1]
Corning non-alkali glass substrate (EAGLE XG (thickness 7 mm × length 30 mm × width 30 mm)) was ultrasonically cleaned in ultrapure water (an ultrapure water device Synergy UV manufactured by Millipore). As the ultrasonic cleaning machine, VS-100III manufactured by ASONE was used. On this alkali-free glass substrate (transparent substrate), a high refractive index layer / transparent metal film / intermediate layer / barrier layer were sequentially formed by the following method.
FIG. 2A shows the admittance locus of the obtained transparent conductor at a wavelength of 570 nm, and FIG. 2B shows the spectral characteristics of the transparent conductor.

(High refractive index layer)
On the transparent substrate described above, TiO ₂ was deposited by electron beam (EB) with ion assistance at 320 mA and a film formation rate of 3 Å / s using a Gener 1300 manufactured by Optorun. The obtained high refractive index layer was 38.7 nm. The ion beam was irradiated at a current of 500 mA, a voltage of 500 V, and an acceleration voltage of 400 V. In the ion beam apparatus, O ₂ gas: 50 sccm and Ar gas: 8 sccm were introduced. The refractive index of light with a wavelength of 570 nm of TiO ₂ was 2.35, but the refractive index of light with a wavelength of 570 nm of the high refractive index layer was 2.41.

(Transparent metal film)
On the high refractive index layer, platinum palladium (Pt 80% by mass, Pd 20% by mass) was sputtered for 0.2 seconds with a vacuum device magnetron sputtering system (MSP-1S), and growth with an average thickness of 0.1 nm was performed. Nuclei formed. The average thickness of the growth nuclei was calculated from the film formation rate at the nominal value of the manufacturer of the sputtering apparatus.
Then, Ag was vapor-deposited by Gener 1300 (210A resistance heating) of Optorun, and the transparent metal film (11.8nm) which consists of Ag was obtained. The film formation rate was 3 Å / s. The plasmon absorption rate of the obtained transparent metal film was 10% or less over a wavelength range of 400 nm to 800 nm.

(Middle layer)
On the transparent metal film, TiO ₂ was deposited by electron beam (EB) without ion assistance with 320 mA at a film formation rate of 3 Å / s under oxygen introduction by a Gener 1300 manufactured by Optorun. The obtained intermediate layer was 10 nm. The refractive index of light with a wavelength of 570 nm of TiO ₂ is 2.35, but the refractive index of light with a wavelength of 570 nm of the intermediate layer is 2.21.

(Barrier layer)
On the intermediate layer, TiO ₂ was subjected to electron beam (EB) deposition while ion-assisted under the same conditions as those for forming the high refractive index layer. The obtained barrier layer was 24.5 nm. The refractive index of light with a wavelength of 570 nm of TiO ₂ was 2.35, but the refractive index of light with a wavelength of 570 nm of the barrier layer was 2.41.

[Example 2]
Yamanaka Semiconductor's white substrate (Φ30 mm, thickness 2 mm) was ultrasonically cleaned in ultrapure water (Ultrapure water device Synergy UV manufactured by Millipore). As the ultrasonic cleaning machine, VS-100III manufactured by ASONE was used. A high refractive index layer / transparent metal film / intermediate layer / barrier layer were sequentially formed on the white plate substrate (transparent substrate) by the following method.
FIG. 4A shows an admittance locus of the obtained transparent conductor at a wavelength of 570 nm, and FIG. 4B shows spectral characteristics of the transparent conductor.

(High refractive index layer)
On the transparent substrate, TiO ₂ was deposited by electron beam (EB) while ion-assisted under the same conditions as those for forming the high refractive index layer of Example 1. The obtained high refractive index layer was 35 nm. The refractive index of light with a wavelength of 570 nm of TiO ₂ was 2.35, but the refractive index of light with a wavelength of 570 nm of the high refractive index layer was 2.41.

(Transparent metal film)
On the high refractive index layer, platinum palladium (Pt 80% by mass, Pd 20% by mass) was sputtered for 0.2 seconds with a vacuum device magnetron sputtering system (MSP-1S), and growth with an average thickness of 0.1 nm was performed. Nuclei formed. The average thickness of the growth nuclei was calculated from the film formation rate at the nominal value of the manufacturer of the sputtering apparatus.
Then, Ag was vapor-deposited by Gener 1300 (210A resistance heating) of Optorun, and the transparent metal film (11.5 nm) which consists of Ag was obtained. The film formation rate was 3 Å / s. The plasmon absorption rate of the obtained transparent metal film was 10% or less over a wavelength range of 400 nm to 800 nm.

(Middle layer)
Oxygen was introduced onto the transparent metal film by Genen 1300 of Optorun so that the total pressure in the vapor deposition apparatus became 2.0 × 10 ⁻² Pa, and Ta ₂ O ₅ was deposited at 400 mA and a film formation rate of 4 Å / s. Electron beam (EB) deposition was performed without ion assist. The obtained intermediate layer was 10 nm. The refractive index of light with a wavelength of 570 nm of Ta ₂ O ₅ is 2.16, but the refractive index of the intermediate layer is 2.06.

(Barrier layer)
On the intermediate layer, Ta ₂ O ₅ was ion beam assisted by electron beam (EB) deposition at 400 mA and a film formation rate of 4 Å / s using a Gener 1300 manufactured by Optorun. The ion beam had a current of 500 mA, a voltage of 500 V, and an acceleration voltage of 500 V, and O ₂ gas: 5 sccm and Ar gas: 20 sccm were introduced into the ion beam apparatus. The resulting barrier layer was 33 nm. The refractive index of light with a wavelength of 570 nm of Ta ₂ O ₅ is 2.16, but the refractive index of light with a wavelength of 570 nm of the barrier layer is 2.20.

[Example 3]
Yamanaka Semiconductor's white substrate (Φ30 mm, thickness 2 mm) was ultrasonically cleaned in ultrapure water (Ultrapure water device Synergy UV manufactured by Millipore). As the ultrasonic cleaning machine, VS-100III manufactured by ASONE was used. A high refractive index layer / transparent metal film / intermediate layer / barrier layer were sequentially formed on the white plate substrate (transparent substrate) by the following method.
FIG. 5A shows the admittance locus of the obtained transparent conductor at a wavelength of 570 nm, and FIG. 5B shows the spectral characteristics of the transparent conductor.

(High refractive index layer)
On the transparent substrate, L-430S-FHS manufactured by Anelva Co., Ar 20 sccm, O ₂ 5 sccm, sputtering pressure 0.3 Pa, room temperature, target side power 300 W, film formation rate 0.74 Å / s, Nb ₂ O ₅ Was RF sputtered. The target-substrate distance was 86 mm. The obtained high refractive index layer was 37 nm. The refractive index of light with a wavelength of 570 nm of Nb ₂ O ₅ is 2.31, but the refractive index of light with a wavelength of 570 nm of the high refractive index layer is 2.35.

(Transparent metal film)
On the high refractive index layer, platinum palladium (Pt 80% by mass, Pd 20% by mass) was sputtered for 0.2 seconds with a vacuum device magnetron sputtering system (MSP-1S), and growth with an average thickness of 0.1 nm was performed. Nuclei formed. The average thickness of the growth nuclei was calculated from the film formation rate at the nominal value of the manufacturer of the sputtering apparatus.
Subsequently, Ag was RF-sputtered using L-430S-FHS manufactured by Anerva Co., with Ar 20 sccm, sputtering pressure 0.3 Pa, room temperature, target-side power 100 W, and film formation rate 2.5 Å / s. The target-substrate distance was 86 mm. The plasmon absorption rate of the obtained transparent metal film (12 nm) made of Ag was 10% or less over a wavelength range of 400 nm to 800 nm.

(Middle layer)
On the transparent metal film, L-430S-FHS manufactured by Anelva Co., Ar 20 sccm, O ₂ 0.75 sccm, N ₂ 4 sccm, sputtering pressure 0.3 Pa, room temperature, target side power 200 W, film formation rate 0.78 mm Nb ₂ O ₅ was RF sputtered at / s. The target-substrate distance was 100 mm. The obtained intermediate layer was 10 nm. The refractive index of light with a wavelength of 570 nm of Nb ₂ O ₅ is 2.31, but the refractive index of light with a wavelength of 570 nm of the intermediate layer is 2.26.

(Barrier layer)
On the intermediate layer, L-430S-FHS manufactured by Anelva Co., Ar 20 sccm, O _{2 2} sccm, sputtering pressure 0.3 Pa, room temperature, target side power 500 W, film formation rate 2.97 Å / s, Nb ₂ O ₅ Was DC sputtered. The target-substrate distance was 100 mm. The resulting barrier layer was 26 nm. The refractive index of light with a wavelength of 570 nm of Nb ₂ O ₅ is 2.31, but the refractive index of light with a wavelength of 570 nm of the barrier layer is 2.35.

[Example 4]
Corning non-alkali glass substrate (EAGLE XG (thickness 7 mm × length 30 mm × width 30 mm)) was ultrasonically cleaned in ultrapure water (an ultrapure water device Synergy UV manufactured by Millipore). As the ultrasonic cleaning machine, VS-100III manufactured by ASONE was used. On this transparent substrate, a high refractive index layer / transparent metal film / intermediate layer / barrier layer were sequentially formed by the following method.
FIG. 6A shows the admittance locus of the obtained transparent conductor at a wavelength of 570 nm, and FIG. 6B shows the spectral characteristics of the transparent conductor.

(High refractive index layer)
On the transparent substrate, under the same conditions as those for forming the high refractive index layer of Example 1, TiO ₂ was subjected to electron beam (EB) deposition while ion-assisted. The obtained high refractive index layer was 32 nm. The refractive index of light with a wavelength of 570 nm of TiO ₂ was 2.35, but the refractive index of light with a wavelength of 570 nm of the high refractive index layer was 2.41.

(Transparent metal film)
On the high refractive index layer, platinum palladium (Pt 80% by mass, Pd 20% by mass) was sputtered for 0.2 seconds with a vacuum device magnetron sputtering system (MSP-1S), and growth with an average thickness of 0.1 nm was performed. Nuclei formed. The average thickness of the growth nuclei was calculated from the film formation rate at the nominal value of the manufacturer of the sputtering apparatus.
Then, Ag was vapor-deposited by Gener 1300 (210A resistance heating) of Optorun, and the transparent metal film (10 nm) which consists of Ag was obtained. The film formation rate was 3 Å / s. The plasmon absorption rate of the obtained transparent metal film was 10% or less over a wavelength range of 400 nm to 800 nm.

(Middle layer)
On the transparent metal film, TiO ₂ was deposited by electron beam (EB) without ion assist under the same conditions as those for forming the intermediate layer of Example 1. The obtained intermediate layer was 31 nm. The refractive index of light with a wavelength of 570 nm of TiO ₂ was 2.35, but the refractive index of the intermediate layer was 2.21.

(Barrier layer)
Using Anelva L-430S-FHS, SiO ₂ was RF sputtered at Ar 20 sccm, O ₂ 5 sccm, sputtering pressure 0.3 Pa, room temperature, target-side power 300 W, and deposition rate 2 Å / s. The target-substrate distance was 86 mm. The resulting barrier layer was 42 nm. The refractive index of light with a wavelength of 570 nm of SiO ₂ is 1.46, but the refractive index of light with a wavelength of 570 nm of the barrier layer is 1.48.

[Example 5]
Yamanaka Semiconductor's white substrate (Φ30 mm, thickness 2 mm) was ultrasonically cleaned in ultrapure water (Ultrapure water device Synergy UV manufactured by Millipore). As the ultrasonic cleaning machine, VS-100III manufactured by ASONE was used. A high refractive index layer / transparent metal film / intermediate layer / barrier layer were sequentially formed on the white plate substrate (transparent substrate) by the following method.
FIG. 7A shows the admittance locus of the obtained transparent conductor at a wavelength of 570 nm, and FIG. 7B shows the spectral characteristics of the transparent conductor.

(High refractive index layer)
On the transparent substrate, under the same conditions as those for forming the high refractive index layer of Example 1, TiO ₂ was subjected to electron beam (EB) deposition while ion-assisted. The obtained high refractive index layer was 33 nm. The refractive index of light with a wavelength of 570 nm of TiO ₂ was 2.35, but the refractive index of light with a wavelength of 570 nm of the high refractive index layer was 2.41.

(Transparent metal film)
On the high refractive index layer, platinum palladium (Pt 80% by mass, Pd 20% by mass) was sputtered for 0.2 seconds with a vacuum device magnetron sputtering system (MSP-1S), and growth with an average thickness of 0.1 nm was performed. Nuclei formed. The average thickness of the growth nuclei was calculated from the film formation rate at the nominal value of the manufacturer of the sputtering apparatus.
Subsequently, Ag was vapor-deposited by Gener 1300 (210A resistance heating) manufactured by Optorun to obtain a transparent metal film (11.0 nm) made of Ag. The film formation rate was 3 Å / s. The plasmon absorption rate of the obtained transparent metal film was 10% or less over a wavelength range of 400 nm to 800 nm.

(Middle layer)
On the transparent metal film, TiO ₂ was deposited by electron beam (EB) without ion assist under the same conditions as those for forming the intermediate layer of Example 1. The obtained intermediate layer was 32 nm. The refractive index of light with a wavelength of 570 nm of TiO ₂ was 2.35, but the refractive index of the intermediate layer was 2.21.

(Barrier layer)
On the intermediate layer, Al ₂ O ₃ was electron-beam (EB) -deposited while being ion-assisted with a current of 310 mA and a film formation rate of 4 に よ り / s using a Gener 1300 manufactured by Optorun. The resulting barrier layer was 22 nm. The ion beam had a current of 500 mA, a voltage of 500 V, and an acceleration voltage of 500 V, and O ₂ gas: 8 sccm and Ar gas: 20 sccm were introduced into the ion beam apparatus. The refractive index of light with a wavelength of 570 nm of Al ₂ O ₃ was 1.71, and the refractive index of light with a wavelength of 570 nm of the barrier layer was 1.71.

[Example 6]
Yamanaka Semiconductor's white substrate (Φ30 mm, thickness 2 mm) was ultrasonically cleaned in ultrapure water (Ultrapure water device Synergy UV manufactured by Millipore). As the ultrasonic cleaning machine, VS-100III manufactured by ASONE was used. On this transparent substrate, a high refractive index layer / transparent metal film / intermediate layer / barrier layer were sequentially formed by the following method.
An admittance locus of the obtained transparent conductor at a wavelength of 570 nm is shown in FIG. 8A, and a spectral characteristic of the transparent conductor is shown in FIG. 8B.

(High refractive index layer)
On the transparent substrate described above, L-430S-FHS manufactured by Anelva was used, Ar 20 sccm, O ₂ 5 sccm, sputtering pressure 0.3 Pa, room temperature, target side power 300 W, film formation rate 0.74 Å / s, Nb ₂ O ₅ was RF sputtering. The target-substrate distance was 86 mm. The obtained high refractive index layer was 35 nm. The refractive index of light with a wavelength of 570 nm of Nb ₂ O ₅ is 2.31, but the refractive index of light with a wavelength of 570 nm of the high refractive index layer is 2.35.

(Transparent metal film)
On the high refractive index layer, platinum palladium (Pt 80% by mass, Pd 20% by mass) was sputtered for 0.2 seconds with a vacuum device magnetron sputtering system (MSP-1S), and growth with an average thickness of 0.1 nm was performed. Nuclei formed. The average thickness of the growth nuclei was calculated from the film formation rate at the nominal value of the manufacturer of the sputtering apparatus.
Then, Ag was vapor-deposited by Gener 1300 (210A resistance heating) of Optorun, and the transparent metal film (10.0 nm) which consists of Ag was obtained. The film formation rate was 3 Å / s. The plasmon absorption rate of the obtained transparent metal film was 10% or less over a wavelength range of 400 nm to 800 nm.

(Middle layer)
On the transparent metal film, RF sputtering of SiO ₂ using L-430S-FHS made by Anelva Co., Ar 20 sccm, O ₂ 5 sccm, sputtering pressure 0.3 Pa, room temperature, target side power 300 W, film formation rate 2 Å / s. did. The target-substrate distance was 86 mm. The obtained intermediate layer was 10 nm. The refractive index of light with a wavelength of 570 nm of SiO ₂ is 1.46, but the refractive index of light with a wavelength of 570 nm of the intermediate layer is 1.44.

(Barrier layer)
On the intermediate layer, Nb ₂ O ₅ was subjected to electron beam (EB) deposition while ion-assisted under the same conditions as those for forming the high refractive index layer. The resulting barrier layer was 27 nm. The refractive index of light with a wavelength of 570 nm of Nb ₂ O ₅ is 2.31, but the refractive index of light with a wavelength of 570 nm of the barrier layer is 2.35.

[Example 7]
A high refractive index layer / transparent metal film / intermediate layer / barrier layer was sequentially laminated on a transparent substrate made of a cycloolefin polymer by the following method. Thereafter, the laminate was patterned by the following method.
The admittance locus of the obtained transparent conductor at a wavelength of 570 nm is shown in FIG. 9A, and the spectral characteristics of the transparent conductor are shown in FIG. 9B.

(High refractive index layer)
On the transparent substrate, L-430S-FHS manufactured by Anelva is used, and ArO 20 sccm, O ₂ 5 sccm, sputtering pressure 0.3 Pa, room temperature, target side power 300 W, film formation rate 1.5 Å / s RF Sputtered. The target-substrate distance was 86 mm. The obtained high refractive index layer was 48 nm. The refractive index of light with a wavelength of 570 nm of ZnO was 2.01, but the refractive index of light with a wavelength of 570 nm of the high refractive index layer was 2.05.

(Transparent metal film)
On the high-refractive index layer, palladium was sputtered for 0.2 seconds with a magnetron sputtering apparatus (MSP-1S) manufactured by Vacuum Device Inc. to form growth nuclei having an average thickness of 0.2 nm. The average thickness of the growth nuclei was calculated from the film formation rate at the nominal value of the manufacturer of the sputtering apparatus.
Subsequently, Ag was RF-sputtered using L-430S-FHS manufactured by Anerva Co., with Ar 20 sccm, sputtering pressure 0.3 Pa, room temperature, target-side power 100 W, and film formation rate 2.5 Å / s. The target-substrate distance was 86 mm. The obtained transparent metal film made of Ag was 7 nm.

(Middle layer)
On the transparent metal film, RF sputtering of SiO ₂ using L-430S-FHS made by Anelva Co., Ar 20 sccm, O ₂ 5 sccm, sputtering pressure 0.3 Pa, room temperature, target side power 300 W, film formation rate 2 Å / s. did. The target-substrate distance was 86 mm. The obtained intermediate layer was 10 nm. The refractive index of light with a wavelength of 570 nm of SiO ₂ is 1.46, but the refractive index of light with a wavelength of 570 nm of the intermediate layer is 1.44.

(Barrier layer)
On the intermediate layer, Anelva L-430S-FHS is used, and ArO 20 sccm, O ₂ 5 sccm, sputtering pressure 0.3 Pa, room temperature, target side power 150 W, and film formation rate 1.4 Å / s are DC sputtered. did. The target-substrate distance was 86 mm. The resulting barrier layer was 35 nm. The refractive index of light with a wavelength of 570 nm of ZnO was 2.01, but the refractive index of light with a wavelength of 570 nm of the first admittance adjusting layer was 2.05.

[Example 8]
A high refractive index layer / transparent metal film / intermediate layer / barrier layer was sequentially laminated on a transparent substrate made of a polycarbonate film by the following method. Thereafter, the laminate was patterned by the following method.
FIG. 10A shows the admittance locus of the obtained transparent conductor at a wavelength of 570 nm, and FIG. 10B shows the spectral characteristics of the transparent conductor.

(High refractive index layer)
On the transparent substrate, L-430S-FHS manufactured by Anelva Co., Ar 20 sccm, O ₂ 5 sccm, sputtering pressure 0.3 Pa, room temperature, target side power 300 W, film formation rate 2.2 Å / s was RF sputtered with ITO. The target-substrate distance was 86 mm. The obtained high refractive index layer was 48 nm. The refractive index of light with a wavelength of 570 nm of ITO is 2.12, but the refractive index of light with a wavelength of 570 nm of the high refractive index layer is 2.10.

(Transparent metal film)
On the high-refractive index layer, palladium was sputtered for 0.2 seconds with a magnetron sputtering apparatus (MSP-1S) manufactured by Vacuum Device Inc. to form growth nuclei having an average thickness of 0.2 nm. The average thickness of the growth nuclei was calculated from the film formation rate at the nominal value of the manufacturer of the sputtering apparatus.
Subsequently, Ag was RF-sputtered using L-430S-FHS manufactured by Anerva Co., with Ar 20 sccm, sputtering pressure 0.3 Pa, room temperature, target-side power 100 W, and film formation rate 2.5 Å / s. The target-substrate distance was 86 mm. The obtained transparent metal film made of Ag was 5.7 nm.

(Middle layer)
On the transparent metal film, RF sputtering of SiO ₂ using L-430S-FHS made by Anelva Co., Ar 20 sccm, O ₂ 5 sccm, sputtering pressure 0.3 Pa, room temperature, target side power 300 W, film formation rate 2 Å / s. did. The target-substrate distance was 86 mm. The obtained intermediate layer was 3 nm. The refractive index of light with a wavelength of 570 nm of SiO ₂ is 1.46, but the refractive index of light with a wavelength of 570 nm of the intermediate layer is 1.44.

(Barrier layer)
On the intermediate layer, ITO was RF-sputtered in the same manner as the film formation conditions for the high refractive index layer. The resulting barrier layer was 42 nm. The refractive index of light with a wavelength of 570 nm of ZnO was 2.12, but the refractive index of light with a wavelength of 570 nm of the barrier layer was 2.10.

[Comparative Example 1]
Referring to Non-Patent Document 1 above, a high refractive index layer 1 / transparent metal film / high refractive index layer 2 (intermediate layer) on a transparent substrate made of Toyobo PET (Cosmo Shine A4300 thickness 50 μm) by the following method Was deposited.
FIG. 11A shows an admittance locus of the obtained transparent conductor at a wavelength of 570 nm, and FIG. 11B shows spectral characteristics of the transparent conductor.

(High refractive index layer 1)
On the transparent substrate, Anelva L-430S-FHS is used, Ar 20 sccm, O ₂ 5 sccm, sputtering pressure 0.3 Pa, room temperature, target-side power 300 W, film formation rate 0.74 Å / s, Nb ₂ O ₅ was RF sputtered. The target-substrate distance was 86 mm. The obtained high refractive index layer was 27.7 nm. As described above, the refractive index of light with a wavelength of 570 nm of Nb ₂ O ₅ is 2.31, but the refractive index of light with a wavelength of 570 nm of the high refractive index layer is 2.35.

(Transparent metal film)
On the high refractive index layer 1, DC sputtering was performed by a small sputtering apparatus (BC4279) manufactured by Nippon Vacuum Technology Co., Ltd. At this time, the target side power was set to 200 W. The film thickness of the obtained transparent metal film was 7.3 nm.

(High refractive index layer 2 (intermediate layer))
On the transparent metal film, L-430S-FHS manufactured by Anelva is used, and Ar is 20 sccm, O ₂ 5 sccm, sputtering pressure is 0.3 Pa, room temperature, target side power is 300 W, and film formation rate is 2.2 Å / s. Sputtered. The target-substrate distance was 86 mm. The obtained high refractive index layer 2 was 36 nm. The refractive index of light with a wavelength of 570 nm of IZO is 2.05, but the refractive index of light with a wavelength of 570 nm of the high refractive index layer 2 is 1.98.

[Comparative Example 2]
Corning non-alkali glass substrate (EAGLE XG (thickness 7 mm × length 30 mm × width 30 mm)) was ultrasonically cleaned in ultrapure water (an ultrapure water device Synergy UV manufactured by Millipore). As the ultrasonic cleaning machine, VS-100III manufactured by ASONE was used. A transparent metal film and a high refractive index layer (intermediate layer) were formed on the alkali-free glass substrate (transparent substrate) by the following method.
FIG. 12A shows the admittance locus of the obtained transparent conductor at a wavelength of 570 nm, and FIG. 12B shows the spectral characteristics of the transparent conductor.

(Transparent metal film)
On the transparent substrate, Al was deposited by electron beam (EB) at a film formation rate of 3 Å / s using a BMC-800T vapor deposition machine manufactured by SYNCHRON. The thickness of the layer made of Al thus obtained was 1 nm.
Subsequently, Ag was RF-sputtered using L-430S-FHS manufactured by Anerva Co., with Ar 20 sccm, sputtering pressure 0.3 Pa, room temperature, target-side power 100 W, and film formation rate 2.5 Å / s. The target-substrate distance was 86 mm. The obtained transparent metal film made of Ag was 10 nm.

(High refractive index layer (intermediate layer))
Using L-430S-FHS manufactured by Anerva, DC sputtering of IZO was performed at Ar 20 sccm, O ₂ 0.1 sccm, sputtering pressure 0.3 Pa, room temperature, target-side power 150 W, and deposition rate 2.0 Å / s. The target-substrate distance was 86 mm. The obtained high refractive index layer was 34 nm. The refractive index of light having a wavelength of 570 nm of IZO was 2.05, and the refractive index of light having a wavelength of 570 nm of the first admittance adjusting layer was 2.09.

[Evaluation]
For the transparent conductor obtained in each of the examples and comparative examples, the water permeability of the barrier layer, the identification of the packing density of the barrier layer, the average light transmittance of the transparent conductor, the luminous transmittance of the transparent conductor, the transparent conductor Table 1 shows the surface electrical resistance of the body and the evaluation results after the reliability test. These were measured by the following method.

<Measurement method of water permeability>
Only the barrier layer was formed on a TAC film (100 mm × 100 mm t (thickness) = 40 μm) under the same conditions as those for the barrier layer described above, and a water vapor transmission rate measuring device (PERMATRAN-W3 / 33 manufactured by MOCON) was used. ) To measure the water permeability. In addition, about the comparative example, the water permeability of the intermediate | middle layer was measured.

<Method for specifying the packing density of the barrier layer>
On the substrate made of BK7 (φ (diameter) = 30 mm t (thickness) = 2 mm) manufactured by SCHOTT GLASS, each layer is formed under the same conditions as the film forming conditions of each layer described above, and the spectral reflectance of the layer is determined. It was measured. On the other hand, the spectral reflectance (theoretical value) when the high refractive index layer has various packing densities was calculated by thin film calculation software (Essential Macleod). And the spectral reflectance calculated by the above-mentioned software and the measured spectral reflectance were collated, and the packing density of the high refractive index layer was specified.

<Measurement method of average light transmittance>
Measuring light (for example, light having a wavelength of 450 nm to 800 nm) is incident from an angle inclined by 5 ° with respect to the normal line of the surface of the transparent conductor, and light transmittance is measured by Hitachi, Ltd .: spectrophotometer U4100. Was measured. The measurement light was incident from the barrier layer or the intermediate layer side.

<Measuring method of luminous transmittance and luminous reflectance>
The luminous transmittance and luminous reflectance were measured with a spectrophotometer (U4100; manufactured by Hitachi High-Technologies Corporation).

<Measurement method of surface electrical resistance>
Measured with a Loresta EP MCP-T360 manufactured by Mitsubishi Chemical Analytech.

<Reliability test evaluation method>
The transparent conductor was placed in an environment of 40 ° C. and 90% for 100 hours. The appearance after the test was visually confirmed and evaluated according to the following criteria.
○: There is no spot (50 μm or more) in the appearance of the transparent conductor after the test. ×: One or more spots (50 μm or more) in the appearance of the transparent conductor after the test.

Further, the optical admittance (equivalent admittance Y _E (x _E , y _E )) of the barrier layer surface, the refractive index n _{env of the} environment in contact with the surface, the equivalent admittance of the transparent conductor, and the optical admittance of the environment (n _env , Table 2 shows the distance ((x _E −n _env ) ² + (y _E ) ² ) ^0.5 with respect to 0). The optical admittance was determined by the following method.

<Method of determining optical admittance>
The optical admittance of the layer constituting the transparent conductor was calculated by the thin film design software Essential Macleod Ver.9.4.375. Note that the thickness d, refractive index n, and absorption coefficient k of each layer necessary for the calculation are separately prepared under the same conditions. A. Woollam Co. Inc. It measured with the VB-250 type | mold VASE ellipsometer made from.

  As shown in Table 1, a transparent conductor including an intermediate layer having a packing density lower than that of the barrier layer between the transparent metal film and the barrier layer has a sufficiently low surface electrical resistance and a high average transmittance. (Examples 1-8). Since the transparent metal film is protected by the intermediate layer, it is presumed that the transparent metal film was not damaged when the barrier layer was formed.

  On the other hand, in Comparative Example 2 in which a high refractive index layer (intermediate layer) was formed on the transparent metal film by DC sputtering, the surface electrical resistance was low and the average transmittance was also low. It is inferred that the transparent metal film was scraped during the formation of the high refractive index layer.

  In particular, when the refractive index of the intermediate layer was less than 1.8 and the refractive index of the barrier layer was 1.8 or more (Examples 6 to 8), the average transmittance was high. It is inferred that plasmon absorption of the transparent metal film was suppressed by the intermediate layer.

  In addition, when the surface has a layer having a high packing density (a layer having a packing density of 1.00 or more) (Examples 1 to 8 and Comparative Example 2), the deterioration of the transparent metal film was small. On the other hand, when a layer having a packing density of 0.93 was provided on the surface (Comparative Example 1), spots were generated after the reliability test.

Further, when the value of ((x _E −n _env ) ² + (y _E ) ² ) ^0.5 exceeded 0.5 (Example 8 and Comparative Example 1), the luminous reflectance was high. In Comparative Example _2, although ^{_{((x E -n env) 2}} + (y E) 2) The value of ^0.5 is small, as shown in Figure 12A, the center admittance locus a horizontal axis of the graph It was not line symmetric. Therefore, as shown in FIG. 12B, there is a region where the light transmittance is low, and the luminous reflectance is high.

  The transparent conductor obtained by the present invention has a low surface electric resistance value and excellent transparency. Also, there is little deterioration with time. Therefore, it is preferably used in various optoelectronic devices such as various types of displays, touch panels, mobile phones, electronic paper, various solar cells, various electroluminescence light control elements, and the like.

DESCRIPTION OF SYMBOLS 1 Transparent substrate 2 High refractive index layer 3 Transparent metal film 4 Intermediate layer 5 Barrier layer 100 Transparent conductor

Claims (8)

A transparent substrate;
A high refractive index layer comprising a dielectric material or an oxide semiconductor material having a refractive index higher than that of light having a wavelength of 570 nm of the transparent substrate;
A transparent metal film having a thickness of 5 nm to 15 nm;
An intermediate layer comprising a dielectric material or an oxide semiconductor material;
A transparent conductor comprising a dielectric material or an oxide semiconductor material and a barrier layer having higher packing density than the intermediate layer in this order;
At least one of the intermediate layer and the barrier layer includes a dielectric material or an oxide semiconductor material having a refractive index higher than that of light having a wavelength of 570 nm of the transparent substrate,
A transparent conductor having an average transmittance of light having a wavelength of 450 nm to 800 nm of 50% or more. The refractive index of light of wavelength 570 nm of the dielectric material or oxide semiconductor material included in the barrier layer is 1.8 or more, and the refraction of light of wavelength 570 nm of the dielectric material or oxide semiconductor material included in the intermediate layer. The transparent conductor of claim 1, wherein the rate is less than 1.8. The dielectric material or oxide semiconductor material included in the intermediate layer includes MgF ₂ , SiO ₂ , CaF ₂ , CeF ₃ , LaF ₃ , LiF, NaF, NdF ₃ , Na ₃ AlF ₆ , Al ₂ O ₃ , MgO, and The transparent conductor according to claim 2, wherein the transparent conductor is one or more selected from the group consisting of ThO ₂ . The dielectric material or oxide semiconductor material included in the barrier layer is HfO ₂ , Y ₂ O ₃ , La ₂ O ₃ , LaAlO ₃ , PrTiO ₃ , SiO _x N _y (x> 0, y> 0), TiO _2. , ITO, ZnO, ZnS, Nb ₂ O ₅ , ZrO ₂ , CeO ₂ , Ta ₂ O ₅ , Ti ₃ O ₅ , Ti ₄ O ₇ , Ti ₂ O ₃ , TiO, SnO ₂ , La ₂ Ti ₂ O ₇ , The transparent conductor according to claim 2, wherein the transparent conductor is at least one selected from the group consisting of IZO, AZO, GZO, ATO, and ICO. The dielectric material or oxide semiconductor material included in the high refractive index layer is TiO ₂ , ITO, ZnO, ZnS, Nb ₂ O ₅ , ZrO ₂ , CeO ₂ , Ta ₂ O ₅ , Ti ₃ O ₅ , Ti ₄ O. 7. The transparent conductor according to claim 1, which is at least one selected from the group consisting of ₇ , Ti ₂ O ₃ , TiO, SnO ₂ , La ₂ Ti ₂ O ₇ , IZO, AZO, GZO, ATO, and ICO.   The transparent conductor according to claim 1, wherein the transparent metal film includes one or more metals selected from the group consisting of silver, copper, gold, platinum group, titanium, and chromium. If the equivalent admittance of said barrier layer surface of the transparent conductor expressed in _{Y E = x E + iy E} , represents the refractive index of light of wavelength 570nm of members or environment in contact with the barrier layer surface at n _env, ( The transparent conductor according to claim 1, wherein (x _E −n _env ) ² + (y _E ) ² ) satisfies ^0.5 <0.5. A transparent substrate, a high refractive index layer including a dielectric material or an oxide semiconductor material having a refractive index higher than that of light having a wavelength of 570 nm of the transparent substrate, a transparent metal film having a thickness of 5 nm to 15 nm, and a dielectric An intermediate layer including a conductive material or an oxide semiconductor material, and a barrier layer including a dielectric material or an oxide semiconductor material and having a packing density higher than that of the intermediate layer in this order. At least one is a method for producing a transparent conductor, which is a layer containing a dielectric material or an oxide semiconductor material having a refractive index higher than the refractive index of light having a wavelength of 570 nm of the transparent substrate,
Preparing a laminate in which the high refractive index layer and the transparent metal film are laminated on the transparent substrate;
Forming the intermediate layer on the transparent metal film;
Forming a barrier layer on the intermediate layer by a sputtering method or an ion-assisted vapor deposition method.

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