WO2022163546A1

WO2022163546A1 - Optical thin film laminate and method for producing same

Info

Publication number: WO2022163546A1
Application number: PCT/JP2022/002297
Authority: WO
Inventors: 洋亮杉原; 明久箕輪; 伸宏中村; 暁渡邉; 邦雄増茂; 尚洋眞下
Original assignee: Ａｇｃ株式会社
Priority date: 2021-01-27
Filing date: 2022-01-21
Publication date: 2022-08-04
Also published as: TW202232777A

Abstract

The purpose of the present invention is to provide: an optical thin film laminate in which interface reflection is suppressed in the contact surface of an absorption layer with high light-shielding properties and a transparent layer with a high refractive index; and a method for producing the optical thin film laminate. The present invention relates to an optical thin film laminate that includes a substrate and an optical thin film layer and in which the optical thin film layer has a layer structure comprising an absorption layer with a refractive index of 1.60-2.50 at a wavelength of 550 nm and an extinction coefficient of 0.20-0.50, and a transparent layer that is layered in contact with the absorption layer and has a refractive index of 1.60-2.50 at a wavelength of 550 nm. The present invention also relates to a method for producing the optical thin film laminate.

Description

Optical thin film laminate and its manufacturing method

The present invention relates to an optical thin film laminate and its manufacturing method.

Conventionally, there is an optical thin film laminate having an optical thin film layer formed by laminating a plurality of layers on a base material. Such optical thin film laminates include, for example, display elements such as OLED (Organic Light Emitting Diode), TFT (Thin Film Transistor) and organic electroluminescence (organic EL), organic EL elements, quantum dot displays, TFT arrays and thin films. It is used in optical elements such as solar cells.

Of the pair of electrodes that constitute the OLED element, the electrode located on the side from which light is extracted as the display element is made of a transparent thin film, while the electrode located on the opposite side is made of a metal thin film. Regardless of whether light is emitted or not, part of light incident from the outside is reflected by the counter electrode toward the light extraction surface. As a result, the visibility and contrast of the display element are lowered. Therefore, conventionally, a circularly polarizing plate is provided on the side from which light is extracted, and the reflected light from the counter electrode is shielded by the circularly polarizing plate, thereby improving the visibility and contrast of the display element.

In addition, in optical elements such as TFT arrays, a conductive substrate is used in which wiring made of a transparent electrode material is formed on a transparent base material. Conventionally, transparent electrode materials such as ITO have been used for the wiring of the conductive substrate, but as the size of the panel increases, metal materials such as copper, which have low electric resistance, are also being used.

Japanese Patent Laid-Open No. 7-142170

However, circularly polarizing plates are expensive, and there are problems such as high product prices and the inability to reduce the thickness of the display element. Another problem with the TFT array for liquid crystals is that when the display is in an off state, part of the light incident from the light extraction surface side is reflected by the copper wiring, resulting in a reddish color.

Therefore, an object of the present invention is to provide an optical thin film laminate and a method for manufacturing the same, which can suppress reflection by providing an absorption layer with high light shielding properties adjacent to a transparent layer with a high refractive index.

As a result of studying the above problems, the present inventors have found that by adjusting the optical constant of the absorption layer in accordance with the refractive index of the transparent layer disposed so as to be in contact with the absorption layer, the absorption layer and the transparent layer The present inventors have found that it is possible to suppress interfacial reflection on the contact surface with and realize low reflection, and have made the present invention.

That is, the present invention includes a substrate and an optical thin film layer,
The optical thin film layer includes an absorption layer having a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm, and a wavelength of 550 nm laminated in contact with the absorption layer. and a transparent layer having a refractive index of 1.60 to 2.50.

In the optical thin film laminate of the present invention, the absorption layer preferably has a physical thickness of 200 to 500 nm.

In the optical thin film laminate of the present invention, it is preferable that the resistivity of the absorption layer is 1×10 ⁻¹ Ωcm or more.

In the optical thin film laminate of the present invention, the absorption layer preferably contains at least one selected from oxides, nitrides, oxynitrides and oxycarbides containing at least two kinds of metal cations.

In the optical thin film laminate of the present invention, the absorption layer preferably contains at least one element selected from the group consisting of Cr, Mn, Fe, Co, Ni, Cu, Ru and Ag.

In the optical thin film laminate of the present invention, the absorption layer contains Cr and Si, and the atomic ratio of Cr to the total amount of Cr and Si in the absorption layer is in the range of 0.10 or more and 0.70 or less. Preferably.

In the optical thin film laminate of the present invention, the absorption layer contains Cr and Al, and the atomic ratio of Cr to the total amount of Cr and Al in the absorption layer is in the range of 0.10 or more and 0.50 or less. Preferably.

In the optical thin film laminate of the present invention, the absorption layer contains Cu and Si, and the atomic ratio of Cu to the total amount of Cu and Si in the absorption layer is in the range of 0.10 or more and 0.95 or less. Preferably.

In the optical thin film laminate of the present invention, the absorption layer contains Cu and Al, and the atomic ratio of Cu to the total amount of Cu and Al in the absorption layer is in the range of 0.30 or more and 0.95 or less. Preferably.

In the optical thin film laminate of the present invention, it is preferable that the absorption layer can be patterned by etching.

Further, the present invention includes a substrate and an optical thin film layer,
A light-emitting device in which the optical thin film layer includes at least an absorption layer, a lower electrode, a light-emitting layer and an upper electrode, and extracts light above a substrate,
the lower electrode is laminated in contact with the absorption layer;
The absorption layer has a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm,
The present invention relates to a light emitting device including the optical thin film laminate of the present invention, wherein the lower electrode is a transparent layer having a refractive index of 1.60 to 2.50 at a wavelength of 550 nm.

The present invention includes a substrate and an optical thin film layer,
the optical thin film layer includes an absorption layer between a metal wire and an insulating layer laminated on top of the metal wire;
The absorption layer is laminated so as to be in contact with the metal wiring and the insulating layer,
The absorption layer has a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm,
The present invention relates to an electric circuit including the optical thin film laminate, wherein the insulating layer is a transparent layer having a refractive index of 1.60 to 2.50 at a wavelength of 550 nm.

The present invention includes a substrate and a plurality of thin film transistors,
the thin film transistor includes a semiconductor layer, an absorption layer, and an insulating layer disposed between the semiconductor layer and the absorption layer;
The insulating layer is laminated so as to be in contact with the absorbing layer,
The absorption layer has a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm,
The thin film transistor array includes the optical thin film laminate of the present invention, wherein the insulating layer is the transparent layer having a refractive index of 1.60 to 2.50 at a wavelength of 550 nm.

The present invention provides a method for manufacturing an optical thin film laminate comprising forming an optical thin film layer on a substrate, comprising:
The formation of the optical thin film layer includes:
forming an absorption layer having a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm; The present invention relates to a method for producing an optical thin film laminate, including forming a transparent layer having a refractive index of 1.60 to 2.50.

The present invention also provides a sputtering target material used in the method for producing an optical thin film laminate of the present invention,
The present invention relates to a sputtering target material for forming the absorption layer having a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm by sputtering.

The optical thin film laminate of the present invention comprises an optical thin film layer provided on a substrate, the optical thin film layer being laminated in contact with an absorbing layer having a specific range of refractive index and extinction coefficient, and being in contact with the absorbing layer. By including a layer structure including a transparent layer having a refractive index within a specific range, interfacial reflection at the contact surface between the transparent layer and the absorption layer is suppressed. As a result, the optical thin film laminate of the present invention can achieve low reflection by the absorption layer with respect to light incident on the contact surface between the transparent layer and the absorption layer.

FIG. 1(a) is a diagram obtained by analyzing the correlation between the refractive index (n2) of the transparent layer, the refractive index (n1) of the absorbing layer, and the extinction coefficient (k1). FIG. 1(b) is a diagram showing the relationship between n1 and k1 that satisfy a reflectance of 1%. 2(a) to 2(d) are sectional views showing an embodiment of the optical thin film laminate of the present invention. FIG. 3(a) is a partial cross-sectional view showing the light emitting device according to the first embodiment of the present invention. FIG. 3(b) is a partial cross-sectional view of an example of a conventional light emitting device. FIG. 4(a) is a plan view showing an electric circuit according to a second embodiment of the present invention, and FIG. 4(b) is a partial cross-sectional view of the electric circuit. FIG. 5(a) is a plan view showing a conventional electric circuit, and FIG. 5(b) is a partial sectional view of the electric circuit. FIG. 6(a) shows a partial cross-sectional view of a thin film transistor array according to a third embodiment of the present invention. FIG. 6(b) shows a partial cross-sectional view of an example of a conventional thin film transistor array.

In this specification, the term "~" used to indicate a numerical range is used to include the numerical values before and after it as lower and upper limits unless otherwise specified.

When the present inventors analyzed the relationship between the refractive index of the transparent layer and the optical constant of the absorption layer for realizing low reflection, it was found that there is a correlation shown in FIG. 1(a). (a) of FIG. 1 shows the refractive index (n2) of the transparent layer when light is incident on the optical thin film layer composed of an absorption layer and a transparent layer laminated so as to be in contact with the absorption layer from the transparent layer side. , the refractive index (n1) and the extinction coefficient (k1) of the absorption layer. FIG. 1(b) shows the relationship between the refractive index (n2) of the transparent layer and the optical constants (refractive index n1, extinction coefficient k1) of the absorbing layer, which satisfy a reflectance of 1%.

Based on the above correlation, the present inventors adjusted the optical constant of the absorption layer placed in contact with the transparent layer in accordance with the refractive index of the transparent layer to a specific range, whereby the transparent layer and the absorption layer It was found that the interfacial reflection on the contact surface with can be suppressed.

The optical thin film laminate of the present invention comprises an absorption layer having a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm, and is laminated in contact with the absorption layer. Interfacial reflection of light incident on the contact surface between the transparent layer and the absorption layer by including a structure composed of a transparent layer having a refractive index of 1.60 to 2.50 at a wavelength of 550 nm in the optical thin film layer. can be reduced, the amount of light absorbed in the absorption layer can be increased, and low reflection can be realized.

In the optical thin film laminate of the present invention, the interface reflectance of light incident on the contact surface between the absorbing layer and the transparent layer which are laminated in contact with each other is preferably 3% or less, more preferably 1% or less. More preferably, it is 0.5% or less. The interface reflectance is determined by optical calculation.

<Optical thin film laminate>
BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the drawings are provided for illustrative purposes and the present invention is in no way limited to those drawings.

(a) to (d) of FIG. 2 are cross-sectional views showing one mode of the optical thin film laminate of the present invention and its modification. The optical thin film layered product 1 shown in FIG. 2( a ) has an optical thin film layer 11 provided on a substrate 6 , and the optical thin film layer 11 is an absorption layer 2 and a transparent layer laminated so as to be in contact with the absorption layer 2 . and layer 3.

As a modification of the embodiment shown in FIG. 2A, as shown in FIG. The thin film layer 202 includes a layer structure in which a first absorption layer 203, a second absorption layer 204, a first transparent layer 205, and a second transparent layer 206 are sequentially laminated, and a second substrate 207 is further laminated. may be

As shown in FIG. 2B, the optical thin film laminate 208 has an optical thin film layer 210 provided on a substrate 209. The optical thin film layer 210 includes a first absorption layer 211, a first transparent layer, and a first absorption layer 211. 212, the second absorption layer 213, and the second transparent layer 214 may be sequentially laminated.

As a modification of the embodiment shown in FIG. 2B, as shown in FIG. A first absorption layer 218 and a first transparent layer 219 are sequentially laminated, and a second absorption layer 221 and a second transparent layer 222 are sequentially laminated via a functional layer 220 having a specific function. may be

In the optical thin film laminate according to the present invention, the number of layers composed of the absorption layer and the transparent layer laminated in contact with the absorption layer may be 1 or may be plural, It can be appropriately determined depending on the material to be used and the application of the optical thin film laminate.

In addition, when the optical thin film laminate includes a plurality of the above-mentioned layer structures, the optical constants of the absorption layer and the transparent layer constituting the layer structure may be different from each other as long as they are within the range specified in the present invention. It can be appropriately determined depending on the material to be used and the application of the optical thin film laminate.

The optical constants of the refractive index and the extinction coefficient of each material constituting the optical thin film layer 11 are determined using the spectroscopic ellipsometry method. is determined by measuring the change in

As used herein, the term "extinction coefficient" refers to a constant that indicates how much light a substance absorbs when light is incident on it. There is a relationship of the following equation between the intensity I of the light at the moment, the intensity _I0 of the incident light, and the extinction coefficient k.
I=I ₀ e ^−αZ
α=4πk/λ
(z: penetration depth of light, α: absorption coefficient, λ: wavelength)
As is clear from the above formula, the extinction coefficient has wavelength dependence, and in this specification, unless otherwise specified, the extinction coefficient at a wavelength of 550 nm is used.

<<Absorptive Layer>>
The absorption layer 2 has a refractive index of 1.60 to 2.50 at a wavelength of 550 nm and an extinction coefficient of 0.20 to 0.50. If either one of the refractive index and the extinction coefficient is out of the above range, the reflectance of light incident on the surface where the absorption layer 2 and the transparent layer 3 are in contact cannot be reduced. The refractive index and extinction coefficient of the absorption layer 2 at a wavelength of 550 nm can be appropriately determined within the above ranges according to the use of the optical thin film laminate. The refractive index of the absorption layer 2 at a wavelength of 550 nm is, for example, preferably 1.7 to 2.4, more preferably 1.8 to 2.3. The extinction coefficient of the absorption layer is, for example, preferably 0.25 to 0.45, more preferably 0.3 to 0.4.

When the optical thin film laminate 1 includes a plurality of the absorption layers, the materials, refractive indices and extinction coefficients thereof may be different from each other or may be the same. can be appropriately selected according to the purpose of providing the .

The physical thickness of the absorption layer 2 is preferably 200-500 nm, more preferably 300-450 nm. By setting the physical film thickness of the absorption layer 2 to 200 nm or more, the light absorption function can be sufficiently exhibited. Further, productivity can be improved by setting the physical film thickness of the absorption layer 2 to 500 nm or less.

Depending on the application of the optical thin film laminate 1, the absorption layer 2 preferably has a high resistivity. In that case, the resistivity of the absorption layer 2 is preferably 1×10 ⁻¹ Ωcm or more, more preferably 1×10 ² Ωcm or more, from the viewpoint of preventing capacitive coupling with other wirings or electrodes. It is preferably 1×10 ³ Ωcm or more.

The absorption layer 2 preferably contains at least one selected from oxides, nitrides, oxynitrides and oxycarbides containing at least two kinds of metal cations. By containing at least two kinds of metal cations, the refractive index of the absorbing layer 2 can be decreased, the extinction coefficient can be increased, and interfacial reflection at the contact surface between the transparent layer 3 and the absorbing layer 2 can be suppressed.

The metal cation contained in the absorption layer 2 contains at least one element selected from the group consisting of Cr, Mn, Fe, Co, Ni, Cu, Ru and Ag from the viewpoint of increasing the extinction coefficient. Among these, Cr or Cu is preferable.

From the viewpoint of reducing the refractive index, the metal cation contained in the absorption layer 2 preferably contains at least one element selected from the group consisting of Si, Al and B. Among these, Si or Al is preferably contained. It is more preferable to include

The absorption layer 2 preferably contains at least a combination of an element with a large extinction coefficient and an element with a small refractive index among the above elements. Specific examples of such combinations include Si and Cr, Si and Cu, Al and Cr, and Al and Cu.

The absorption layer 2 preferably contains Cr and Si from the viewpoint of decreasing the refractive index and increasing the extinction coefficient. In this case, the atomic ratio of Cr to the total amount of Cr and Si in the absorption layer 2 (Cr/Cr+Si) is preferably 0.10 or more and 0.70 or less, more preferably 0.15 or more and 0.60. or less, more preferably 0.20 or more and 0.50 or less. By setting the atomic ratio of Cr to the total amount of Cr and Si in the absorbing layer 2 within the above range, the refractive index of the absorbing layer 2 can be decreased and the extinction coefficient can be increased.

The absorption layer 2 preferably contains Cr and Al from the viewpoint of decreasing the refractive index and increasing the extinction coefficient. In this case, the atomic ratio of Cr to the total amount of Cr and Al in the absorption layer 2 (Cr/Cr+Al) is preferably 0.10 or more and 0.50 or less, more preferably 0.12 or more and 0.40. It is below. It is more preferably 0.15 or more and 0.30 or less. By setting the atomic ratio of Cr to the total amount of Cr and Al in the absorbing layer 2 within the above range, the refractive index of the absorbing layer 2 can be decreased and the extinction coefficient can be increased.

The absorption layer 2 preferably contains Cu and Si from the viewpoint of decreasing the refractive index and increasing the extinction coefficient. In this case, the atomic ratio of Cu to the total amount of Cu and Si in the absorption layer 2 (Cu/Cu+Si) is preferably 0.10 or more and 0.95 or less, more preferably 0.20 or more and 0.90. It is below. It is more preferably 0.30 or more and 0.85 or less. By setting the atomic ratio of Cu to the total amount of Cu and Si in the absorbing layer 2 within the above range, the refractive index of the absorbing layer 2 can be decreased and the extinction coefficient can be increased.

The absorption layer 2 preferably contains Cu and Al from the viewpoint of decreasing the refractive index and increasing the extinction coefficient. In this case, the atomic ratio (Cu/Cu+Al) of Cu to the total amount of Cu and Al in the absorption layer 2 is preferably 0.30 or more and 0.95 or less, more preferably 0.40 or more and 0.90. It is below. It is more preferably 0.50 or more and 0.85 or less. By setting the atomic ratio of Cu to the total amount of Cu and Al in the absorbing layer 2 within the above range, the refractive index of the absorbing layer 2 can be decreased and the extinction coefficient can be increased.

Preferably, the absorption layer 2 can be patterned by etching. The etching method is not particularly limited, and conventionally known methods such as dry etching and wet etching can be used as appropriate. _From the _viewpoint of manufacturing cost _, the _etching _method used in the manufacture of displays is particularly preferable. A chlorine-based dry etch using gas, _BCl3 gas, or the like is preferred. For wet etching, an etchant containing a mixed acid of phosphoric acid/acetic acid/nitric acid, ammonium fluoride solution, hydrofluoric acid, hydrochloric acid, ferric chloride, oxalic acid, sulfuric acid, hydrogen peroxide solution, etc. is preferable. .

The absorption layer 2 preferably has e ^−αd [α: absorption coefficient (unit: cm ⁻¹ ), d: film thickness (unit: nm)] of 0.15 or less, more preferably 0.10 or less. More preferably, it is 0.05 or less. By setting the e ^-αd of the absorbing layer 2 to 0.15 or less, the interface reflectance can be lowered.

<<transparent layer>>
The transparent layer 3 is a layer having a refractive index of 1.60 to 2.50 at a wavelength of 550 nm. The refractive index of the transparent layer 3 at a wavelength of 550 nm can be appropriately determined within the above range according to the application of the optical thin film laminate 1 . The refractive index of the transparent layer 3 at a wavelength of 550 nm is, for example, preferably 1.7 to 2.3, more preferably 1.8 to 2.2.

When the optical thin film laminate 1 includes a plurality of transparent layers, the materials and refractive indices thereof may be different from each other or may be the same. can be adjusted accordingly.

The physical thickness of the transparent layer 3 is not particularly limited, and can be appropriately adjusted according to the use of the optical thin film laminate 1 and the purpose of providing the transparent layer 3. For example, it is preferably 10 to 1000 nm, more preferably 10 to 1000 nm. 20 to 800 nm, more preferably 25 to 500 nm.

Materials for the transparent layer 3 include, for example, ITO (Indium Tin Oxide), IZO ₍ Indium Zinc Oxide), Ag, _SiNx , SiON, PbTe, Y2O3 _, _ThO2 _, _Bi2O3 _, _Gd2O3 . , _La2O3 , _Pr6O11 , _HfO2 , _Nd2O3 _, _SiOx , _ZnO , _Sb2O3 , _ZrO2 , _Ta2O5 _, _CeO2 , _Cr2O3 _, _Nb2O5 _, _TiO ₂ , ZnS _, SiC, ZnSe, _Sb2S3 , Si, etc., or mixtures thereof.

In the transparent layer 3, e ^−αd [α: absorption coefficient (unit: cm ⁻¹ ), d: film thickness (unit: nm)] is preferably 0.80 or more, more preferably 0.90 or more, More preferably, it is 0.95 or more. When the e ^-αd of the transparent layer 3 is 0.80 or more, the brightness of the display can be increased.

<<Substrate>>
The optical thin film laminate 1 of the present invention may have the absorption layer 2 and the transparent layer 3 provided on the substrate 6 . The substrate 6 preferably has transparency. The substrate 6 is not particularly limited, and examples thereof include glass, resin, glass-ceramics, and sapphire. The substrate may or may not be reinforced. The substrate may be an amorphous substrate or a crystalline substrate or a combination thereof.

Examples of glass include soda lime glass, aluminosilicate glass, borosilicate glass, aluminoborosilicate glass, quartz glass, alkali-free glass, and lead glass. Examples of resins include acrylic resins, styrene resins, polycarbonate resins, epoxy resins, polyethylene resins, polyester resins, polyimide resins, and silicone resins. The substrate may include amorphous or crystalline films.

The shape of the substrate 6 is not particularly limited, and examples thereof include a plate shape and a roll shape.

The thickness of the substrate 6 is appropriately selected according to the intended use, and is preferably 0.2 mm to 2.0 mm, for example. When the thickness of the substrate 6 is 0.2 mm or more, the bending strength of the substrate 6 can be improved. When the thickness of the substrate 6 is 2.0 mm or less, the weight of the optical thin film laminate 1 can be reduced. The thickness of the substrate 6 is more preferably 0.4 mm or more, still more preferably 0.5 mm or more. The thickness of the substrate 6 is more preferably 1.8 mm or less, still more preferably 1.6 mm or less.

The surface of the substrate 6 is preferably smooth. The surface of the substrate 6 may be surface-treated as necessary. Examples of surface treatment methods here include corona treatment, vapor deposition, electron beam treatment, high-frequency discharge plasma treatment, sputtering, ion beam treatment, atmospheric pressure glow discharge plasma treatment, and alkali treatment. , an acid treatment method, and the like.

<Embodiment of optical thin film laminate>
An embodiment of the optical thin film laminate 1 of the present invention will be described in detail with reference to the drawings. The embodiment described below shows a preferred specific example. Therefore, the numerical values, shapes, materials, components, arrangement positions and connection forms of components, etc. shown in the following embodiments are examples and are not intended to limit the present disclosure. Each figure is a schematic diagram and is not necessarily strictly illustrated. Moreover, in each figure, the same code|symbol is attached|subjected to the substantially same structure, and the overlapping description is abbreviate|omitted or simplified.

<<First Embodiment-Light Emitting Device>>
A first embodiment of the present invention is a light-emitting device that includes the above-described optical thin film laminate of the present invention and extracts light above a substrate, comprising a substrate and an optical thin film layer, the optical thin film layer comprising: It includes at least an absorption layer, a bottom electrode, a light emitting layer and a top electrode. In the light-emitting device of this embodiment, the absorption layer is the absorption layer 2, the lower electrode is the transparent layer 3, and the lower electrode is stacked in contact with the absorption layer. The lower electrode may be laminated on the absorption layer 2 by arranging a transparent conductive film.

FIG. 3(a) shows a cross-sectional view of the light emitting element 7 of the first embodiment. The light-emitting element 7 of FIG. 3A comprises a TFT backplane 302, an absorption layer 312, a lower electrode 313, a first organic layer 304, a light-emitting layer 305, and a second organic layer 306 on a first substrate 301. , an upper electrode 307 , a thin film encapsulating layer 308 , a resin layer 309 and a second substrate 310 are stacked in this order, and emits light upward from the first substrate 301 .

In the first embodiment, the absorption layer 312 is an absorption layer having a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm. is a transparent layer having a refractive index of 1.60 to 2.50 at a wavelength of 550 nm. A lower electrode 313 is stacked in contact with the absorption layer 312 .

(b) of FIG. 3 is a cross-sectional view of an example of a conventional light-emitting device. The light-emitting element 8 of FIG. 3B comprises a TFT backplane 302, a reflective electrode 303, a first organic layer 304, a light-emitting layer 305, a second organic layer 306, and an upper electrode 307 on a first substrate 301. , a thin film encapsulating layer 308 , a resin layer 309 , a second substrate 310 , and a circularly polarizing plate 311 are laminated in this order, and emits light upward from the first substrate 301 . An example of such a conventional light-emitting device is an organic EL device provided with a polarizing layer described in Japanese Patent Laid-Open No. 7-142170.

In the conventional light-emitting element 8 shown in FIG. 3B, external light 320 and light 321 from the light-emitting layer 305 are reflected by the internal metal electrode (reflective electrode 303), making it difficult to obtain a clear black display. Luminous efficiency from layer 305 is reduced. To address such a problem, the conventional light-emitting element 8 can suppress reflection of external light 320 and light 321 from the light-emitting layer 305 incident on the reflective electrode 303 by the circularly polarizing plate 311 provided on the viewing surface. . However, the circularly polarizing plate is expensive, and there is a problem that the product price is high.

In the first embodiment of the present invention, an absorption layer 312 having a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm, and and a lower electrode 313 which is a transparent layer having a refractive index of 1.60 to 2.50 at a wavelength of 550 nm and which is laminated in contact therewith. With such a configuration, reflection of external light 320 and light 321 from the light emitting layer 305 can be effectively suppressed without using an expensive circularly polarizing plate.

The material exemplified as the material of the substrate 6 can be used for the first substrate 301 . Among the materials for the substrate 6 described above, glass or resin is preferable.

The TFT backplane 302 is a circuit for driving an organic light emitting diode (OLED) arranged in each pixel, and includes scanning lines, data lines, and thin film transistors.

For the absorbent layer 312, the materials exemplified above as the material for the absorbent layer 2 can be used. If the absorption layer 312 is conductive, the potential may change due to the potential of an adjacent pixel. Therefore, the absorption layer 312 is preferably an insulator. From the viewpoint of ensuring sufficient insulation, the material of the absorption layer 312 preferably contains Cu and Si.

For the lower electrode 313, the materials exemplified above as the material of the transparent layer 3 can be used. The lower electrode 313 preferably contains a conductive metal oxide such as ITO, IZO, GZO (Gadoped ZnO), AZO (Aldoped ZnO). The lower electrode 313 functions as an anode. The lower electrode 313 is a layer provided mainly to provide a suitable work function for hole injection. The physical film thickness of the lower electrode is preferably 10 to 100 nm, more preferably 20 to 50 nm, from the viewpoint of surface flatness. The lower electrode 313 may be provided by disposing a transparent conductive film on the absorption layer 312 .

The first organic layer 304 includes a hole injection layer and a hole transport layer from the lower electrode 313 side.

The hole injection layer is required to have a small ionization potential difference in order to lower the hole injection barrier from the lower electrode 313 . Improving the charge injection efficiency from the electrode interface in the hole injection layer reduces the drive voltage of the device and increases the charge injection efficiency. Polystyrene sulfonic acid (PSS)-doped polyethylenedioxythiophene (PEDOT:PSS) is widely used as a polymer, and phthalocyanine-based copper phthalocyanine (CuPc) is widely used as a low molecule.

The hole transport layer serves to transport holes injected from the hole injection layer to the light emitting layer 305 . It is necessary to have suitable ionization potential and hole mobility. Specific examples of the hole transport layer include triphenylamine derivatives, N,N'-bis(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4,4'-diamine (NPD), N,N'-diphenyl-N,N'-bis[N-phenyl-N-(2-naphthyl)-4'-aminobiphenyl-4-yl]-1,1'-biphenyl-4, 4′-diamine (NPTE), 1,1-bis[(di-4-tolylamino)phenyl]cyclohexane (HTM2) and N,N′-diphenyl-N,N′-bis(3-methylphenyl)-1, 1'-diphenyl-4,4'-diamine (TPD) and the like are used. The thickness of the hole transport layer is preferably 10 nm to 150 nm. The thinner the hole transport layer is, the lower the voltage can be. However, the thickness is preferably 10 nm to 150 nm because of the problem of short circuit between electrodes.

The light-emitting layer 305 is a layer that provides a field for recombination of injected electrons and holes, and is preferably made of a material with high light-emitting efficiency. Specifically, the light-emitting host material and light-emitting dye doping material used in the light-emitting layer 305 function as recombination centers for holes and electrons injected from the lower electrode 313 and the upper electrode 307 . Doping luminescent dyes into the luminescent host material in the luminescent layer 305 provides high luminous efficiency and converts the emission wavelength. Further, the light-emitting material is not limited to organic materials, and may be quantum dots or perovskite materials.

As the light-emitting host material and light-emitting dye doping material used in the light-emitting layer 305, materials that have an appropriate energy level for charge injection, are excellent in chemical stability and heat resistance, and form a homogeneous amorphous thin film are used. preferable. In addition, it is preferable to use a material which is excellent in the kind of emission color and color purity and which has high luminous efficiency. Light-emitting materials that are organic materials include low-molecular-weight materials and high-molecular-weight materials. Further, they are classified into fluorescent materials and phosphorescent materials according to their light emission mechanism.

Specific examples of the light-emitting host material and light-emitting dye doping material used in the light-emitting layer 305 include tris(8-quinolinolato)aluminum complex (Alq ₃ ), bis(8-hydroxy)quinaldine aluminum phenoxide (Alq ' ₂ OPh), bis(8-hydroxy)quinaldine aluminum-2,5-dimethylphenoxide (BAlq), mono(2,2,6,6-tetramethyl-3,5-heptanedionato)lithium complex ( Liq), mono(8-quinolinolato) sodium complex (Naq), mono(2,2,6,6-tetramethyl-3,5-heptanedionato)lithium complex, mono(2,2,6,6-tetra metal complexes of quinoline derivatives such as methyl-3,5-heptanedionate) sodium complex and bis(8-quinolinolate) calcium complex (Caq ₂ ), tetraphenylbutadiene, phenylquinacdrine (QD), anthracene, perylene and coronene, etc. of fluorescent substances.

A quinolinolate complex is preferable as the light-emitting host material, and an aluminum complex containing 8-quinolinol or a derivative thereof as a ligand is particularly preferable. Quantum dots include, for example, CdTe, ZnCdSe/ZnS, CdSe/ZnS and Cu-In-S/ZnS. Examples of perovskite materials include CH ₃ NH ₃ PbI ₃ and CsPbX ₃ (X=Cl, Br or I).

The second organic layer 306 includes an electron transport layer and an electron injection layer from the lower electrode 313 side.

The electron transport layer is a layer for transporting electrons injected from the upper electrode 307 . Electron-transporting layers include, for example, quinolinole aluminum complexes (Alq3), oxadiazole derivatives [such as 2,5-bis(1-naphthyl)-1,3,4-oxadiazole (BND) and 2-(4- t-butylphenyl)-5-(4-biphenyl)-1,3,4-oxadiazole (PBD)], triazole derivatives, bathophenanthroline derivatives, silole derivatives and the like.

The electron injection layer is preferably one that enhances electron injection efficiency. Specifically, the electron injection layer is preferably a layer in which the cathode interface is doped with an alkali metal such as lithium (Li) or cesium (Cs).

The upper electrode 307 can be formed using the same material as the lower electrode 313 and by the same method. The top electrode 307 preferably contains a conductive metal oxide such as IZO, ITO, Ag, AgMg, for example. The upper electrode 307 preferably has a transmittance of 80% or more, more preferably 90% or more, for light with a wavelength of 400 to 800 nm. Also, in order to improve the luminous efficiency, the physical thickness of the upper electrode 307 is preferably 30 nm or more, more preferably in the range of 100 to 300 nm, in order to provide a sufficiently low resistivity.

The thin film encapsulating layer 308 is a thin film made of an inorganic material and covering the laminate on the first substrate 301 . The thin film encapsulating layer 308 has a role of protecting each laminate before forming the encapsulating structure and suppressing permeation of moisture from inside and outside of the encapsulating structure after forming the encapsulating structure.

For the thin film sealing layer 308, it is preferable to use a material with low permeability to moisture, oxygen, etc., that is, a material having a dense structure. In particular, the material of the thin film sealing layer 308 is preferably resin, silicon, carbon or aluminum oxide, nitride or oxynitride. Specific examples include epoxy resin, silicon nitride, silicon oxide, silicon oxynitride, carbon oxide, carbon nitride, and aluminum oxide.

Examples of the method for forming the thin film encapsulating layer 308 include dry processes such as vacuum deposition, electron beam deposition, sputtering, reactive sputtering, ion plating, and vapor deposition. It is preferred to use the method.

The resin layer 309 is a layer arranged between the thin film encapsulating layer 308 and the second substrate 310, increases the adhesion between the second substrate 310 and the thin film encapsulating layer 308, and increases the strength of the light emitting element 7. It has a role to improve

Examples of materials for the resin layer 309 include curable resins such as epoxy resins, acrylic resins, and silicone resins. In addition, since the light emitting element 7 is of a top emission type, the resin layer 309 also has high light transmittance like the thin film sealing layer 308, and has a refractive index different from that of the adjacent thin film sealing layer 308 and the second substrate 310. It is preferable to use materials with a small difference.

Examples of methods for forming the resin layer 309 include the following methods. First, a curable resin is uniformly applied onto the thin film sealing layer 308 or the second substrate 310 by various coating methods such as a dispensing method, a printing method, and a die coating method. After bonding the first substrate 301 and the second substrate 310 together, the resin layer 309 can be formed by curing the curable resin with heat, light, a curing agent, or the like.

The material exemplified as the material of the substrate 6 can be used for the second substrate 310 . Among the materials for the substrate 6 described above, resin is preferable.

As a modification of the first embodiment of the present invention, a TFT back plane, a lower electrode, an absorption layer, a light emitting layer, an organic layer, an upper electrode, a thin film sealing layer, a resin layer, and a substrate are sequentially laminated on a substrate. A light-emitting element having a structure and extracting light upward from a substrate can be mentioned. In this modification, the light-emitting layer is laminated in contact with the absorption layer, and the absorption layer has a refractive index of 1.60 to 2.50 at a wavelength of 550 nm and an extinction coefficient of 0.20 to 0.50. The absorption layer 2 is the light-emitting layer, and the transparent layer 3 has a refractive index of 1.60 to 2.50 at a wavelength of 550 nm.

<<Second Embodiment>>
A second embodiment of the present invention includes the above-described optical thin film laminate of the present invention, wherein an absorbing layer is provided between the metal wiring formed on the substrate and the insulating layer formed on the metal wiring. An electric circuit is formed in contact with the metal wiring and the insulating layer. In the electric circuit of this embodiment, the absorbing layer is the absorbing layer 2 and the lower electrode is the transparent layer 3 .

FIG. 4(a) shows a plan view of the electric circuit 9 of the second embodiment, and FIG. 4(b) shows a partial cross-sectional view thereof [a cross-sectional view of the dashed line portion in FIG. 4(a)]. . As shown in (b) of FIG. 4, the electric circuit 9 includes a first substrate 401 and a second substrate 402 which are arranged to face each other, and an electric circuit between the first substrate 401 and the second substrate 402. A liquid crystal layer 403 is provided on the first substrate 401 , and metal wirings (gate wirings 404 and auxiliary capacitor wirings 405 ) are arranged on the first substrate 401 .

A first absorption layer 406 is laminated on the gate wiring 404 . A second absorption layer 413 is laminated on the auxiliary capacitance wiring 405 , a source electrode 408 , a drain electrode 409 and a pixel electrode 410 are arranged with a gate insulating film 407 interposed therebetween. A semiconductor element 411 is located. The first absorption layer 406 and the second absorption layer 413 and the gate insulating film 407 are arranged in contact with each other.

A third absorption layer 412 is laminated on the source electrode 408 and a fourth absorption layer 416 is laminated on the drain electrode 409 . Between the third absorption layer 412 and the fourth absorption layer 416 and the liquid crystal layer 403 , a protective film 414 is arranged in contact with the third absorption layer 412 and the fourth absorption layer 416 . A color filter 415 is arranged between the liquid crystal layer 403 and the second substrate 402 .

FIG. 5(a) shows a plan view of an example of a conventional electric circuit, and FIG. 5(b) shows a partial cross-sectional view thereof [a cross-sectional view of the broken line portion in FIG. 5(a)]. The electric circuit 10 shown in FIG. 5B is not arranged so that the absorption layers are in contact with the gate wiring 404, the auxiliary capacitor wiring 405, the source electrode 408, and the drain electrode 409, respectively. It is different from the electric circuit 9 shown in (b).

That is, as shown in FIG. 5(b), the electric circuit 10 includes a first substrate 401 and a second substrate 402 arranged to face each other, and a first substrate 401 and a second substrate 402. A liquid crystal layer 403 is provided therebetween, and metal wirings (gate wirings 404 and auxiliary capacitance wirings 405) are arranged on the first substrate 401 .

In the conventional electric circuit 10, a source electrode 408, a drain electrode 409, and a pixel electrode 410 are arranged above the gate wiring 404 and the auxiliary capacitance wiring 405 with a gate insulating film 407 interposed therebetween. A semiconductor element 411 is positioned between.

In the conventional electric circuit 10 , a protective film 414 is arranged between the source electrode 408 and the drain electrode 409 and the liquid crystal layer 403 . A color filter 415 is arranged between the liquid crystal layer 403 and the second substrate 402 .

In the conventional electric circuit 10, the metal wiring (drain electrode 409, source electrode 408, auxiliary capacitor wiring 405, gate wiring 404) is formed of a metal material containing copper (Cu). There was a problem that the light 420 was reflected and the appearance was tinged with brown. An example of an electric circuit in which metal wiring is made of a metal containing copper is described in Japanese Patent Application Laid-Open No. 2020-88014.

In the electric circuit 9 of the second embodiment, the first absorption layer 406, the second absorption layer 413, the third absorption layer 412, and the fourth absorption layer 416 have a refractive index of 1.60 at a wavelength of 550 nm. ˜2.50 and an absorption layer with an extinction coefficient of 0.20 to 0.50. The gate insulating film 407 and protective film 414 are transparent layers having a refractive index of 1.60 to 2.50 at a wavelength of 550 nm. According to the electric circuit 9 of the second embodiment, the surface of the metal wiring can be blackened by the absorption layer to prevent a brown appearance. In addition, the interface reflection between the gate insulating film 407, the protective film 414, and the metal wiring is suppressed, the reflection of the external light 420 is reduced, and a deeper black color can be exhibited.

Materials exemplified as the material of the substrate 6 can be used for the first substrate 401 and the second substrate 402 . Among the materials for the substrate 6 described above, glass is preferable in terms of adhesion to the metal wiring.

For the first absorbent layer 406, the second absorbent layer 413, the third absorbent layer 412, and the fourth absorbent layer 416, the materials exemplified as the material for the absorbent layer 2 can be used. The first absorption layer 406, the second absorption layer 413, the third absorption layer 412, and the fourth absorption layer 416 may be conductors or insulators. can be adjusted accordingly.

Materials exemplified as the material of the transparent layer 3 can be used for the gate insulating film 407 and the protective film 414 . Among the materials for the transparent layer 3 described above, SiN _x , AlO _x , AlN, ZnO, TiO ₂ , Ga ₂ O ₃ , Y ₂ O ₃ , HfO ₂ and Ta ₂ O ₅ are preferable in terms of refractive index.

<<Third Embodiment>>
A third embodiment of the present invention is a thin film transistor array including the optical thin film laminate of the present invention described above and having a plurality of thin film transistors provided on a substrate, the thin film transistors comprising a semiconductor layer, an absorption layer, the semiconductor A thin film transistor array comprising an insulating layer disposed between a layer and said absorber layer. In the thin film transistor array of this embodiment, the absorption layer is the absorption layer 2 and the insulating layer is the transparent layer 3 .

FIG. 6(a) shows a partial cross-sectional view of the thin film transistor array 15 of the third embodiment. As shown in FIG. 6A, the thin film transistor array 15 includes a semiconductor layer 602, an absorption layer 603, and a light shielding insulating layer 604 disposed between the semiconductor layer 602 and the absorption layer 603 on a substrate 601. . A gate insulating layer 605 , a source electrode 606 , and a drain electrode 607 are provided over the light-shielding insulating layer 604 . A source electrode 606 and a drain electrode 607 are electrically connected to the semiconductor layer 602 . A gate electrode 608 is provided on the gate insulating layer 605, and an interlayer insulating layer 609 and a protective layer 610 are sequentially stacked. A pixel electrode 611 electrically connected to the drain electrode 607 is provided over the protective layer 610 .

A partial cross-sectional view of an example of a conventional thin film transistor array 16 is shown in (b) of FIG. The thin film transistor array 16 of FIG. 6B differs from the thin film transistor array 15 of the third embodiment in that a light shielding layer 612 is arranged instead of the absorption layer 603 in the thin film transistor array 15 of the third embodiment. is different. An example of such a conventional thin film transistor array is disclosed in Japanese Patent Application Laid-Open No. 8-220558.

In the conventional thin film transistor array 16, when the backlight light 13 or the stray light 62 is incident on the semiconductor layer 602, a leakage current is generated in the thin film transistor array 16. Therefore, the light shielding layer 612 is arranged so as to be in contact with the semiconductor layer 602 to block light. there is However, the conventional thin film transistor array 16 has a problem that it cannot completely prevent the stray light 62 from entering the semiconductor layer 602 . In addition, since the light-shielding layer 612 is a layer containing metal, it forms a capacitance with the source electrode 606 and the drain electrode 607, causing crosstalk and degrading image quality.

In the thin film transistor array 15 of the third embodiment, the absorption layer 603 has a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm. . Also, the light shielding insulating layer 604 is a transparent layer having a refractive index of 1.60 to 2.50 at a wavelength of 550 nm. This suppresses reflection of incident light at the interface between the light shielding insulating layer 604 and the absorbing layer 603, and the stray light 62 can be sufficiently absorbed. In addition, by using an insulator for the absorption layer 603, formation of capacitance with the source electrode 606 and the drain electrode 607 can be suppressed, and crosstalk can be prevented.

The material exemplified as the material of the substrate 6 can be used for the substrate 601 . Among the materials for the substrate 6 described above, glass is preferable in terms of adhesion to the light shielding film.

The material exemplified as the material of the absorbent layer 2 can be used for the absorbent layer 603 . The absorption layer 603 is preferably an insulator from the viewpoint of preventing the above-described capacitance crosstalk.

Materials exemplified as the material of the transparent layer 3 can be used for the light shielding insulating layer 604 . Among the materials for the transparent layer 3 described above, SiN _x , AlO _x , AlN, ZnO, TiO ₂ , Ga ₂ O ₃ , Y ₂ O ₃ , HfO ₂ and Ta ₂ O ₅ are preferable in terms of refractive index.

<Method for producing optical thin film laminate>
An optical thin film laminate is obtained by laminating an optical thin film including a transparent layer and an absorbing layer on the surface of a substrate. Optical thin films can be manufactured using coating, deposition and methods known in the art. The optical thin film can be applied by physical vapor deposition (eg, vacuum deposition, ion plating, sputtering) or chemical vapor deposition (eg, thermal CVD, plasma CVD, optical CVD). Among them, the sputtering method is preferable because it is excellent in uniformity of film thickness and productivity.

The manufacturing method of the present invention is a method for manufacturing an optical thin film laminate including forming an optical thin film layer on a substrate. 50 and an extinction coefficient of 0.20 to 0.50, and a refractive index of 1.60 to 2.50 at a wavelength of 550 nm to be laminated in contact with the absorption layer The method is characterized by including forming a transparent layer.

<Sputtering target material>
As an embodiment of the present invention, the absorption layer having a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm in the manufacturing method of the present invention is formed by a sputtering method. Sputtering target materials for forming by.

The composition of the sputtering target material is adjusted according to the desired composition of the absorption layer. The composition of the sputtering target material is similar to the composition of the absorption layer 2 described above. As the target, an alloy material target may be used, chips processed into thin plates may be uniformly arranged on a pure metal target, or a pure metal target may be divided into pieces and uniformly backed. You may arrange|position by sticking on a plate.

Specifically, for example, the sputtering target material contains 10 to 95 atomic % of at least one element selected from the group consisting of Cr, Mn, Fe, Co, Ni, Cu, Ru and Ag. is preferred, more preferably 12 to 90 atomic %, still more preferably 15 to 85 atomic %.

Although several embodiments of the present invention and modifications thereof have been described above, the present invention is not limited to the description of the above-described embodiments, and is within the scope of the present invention. Needless to say, it can be changed as appropriate.

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

[Experimental example 1]
<Preparation of optical thin film laminate>
An optical thin film laminate having a square plate glass (AN-100 manufactured by AGC) of 50 mm × 50 mm × 0.5 mm as a substrate, and having an absorption layer and a transparent layer composed of the materials shown in Table 1 on one surface of the substrate. were sequentially laminated by a sputtering method. In Tables 1 and 2, Examples 1 to 11 are examples, and Examples 12 to 18 are comparative examples.

(Formation of absorption layer)
In the chamber of a magnetron sputtering apparatus, the metal chips (10 mm long, 10 mm wide, 1 mm thick) shown in Tables 1 and 2 were placed on a metal target (6 inches in diameter) to form a 50 mm x 50 mm x 0.5 mm chip. A 5 mm rectangular plate-shaped glass (AN-100 manufactured by AGC) was mounted on a substrate holder and evacuated to 3×10 ⁻⁴ Pa or less. Gases were introduced in the configuration shown in Table 1, the pressure was adjusted to 3×10 ⁻¹ Pa, a pulse DC voltage of 500 W was applied to the target to generate plasma, and a compound was formed on the substrate by sputtering. The chemical composition of the absorbing layer was controlled by changing the number of metal chips loaded on the target.

(Formation of transparent layer)
The targets shown in Tables 1 and 2 were placed in the chamber of the magnetron sputtering apparatus, the glass with the absorption layer formed thereon was mounted on the substrate holder, and the chamber was evacuated to 3×10 ⁻⁴ Pa or less. Gases were introduced in the configurations shown in Tables 1 and 2, the pressure was adjusted to 3×10 ⁻¹ Pa, a pulse DC voltage of 500 W was applied to the target to generate plasma, and a compound was formed on the substrate by sputtering.

<Measurement of refractive index, extinction coefficient, and film thickness>
Measured at an incident angle of 50 °, 60 °, 70 ° using a spectroscopic ellipsometer (JA Woollam Japan Co., M-2000DI), analysis software (JA Woollam Japan Co., WVASE32) was used to fit the optical model. The refractive index n and extinction coefficient k of the absorbing layer and the transparent layer were calculated and the values at a wavelength of 550 nm are shown in Tables 1 and 2. Tables 1 and 2 show calculated values of e ^−αd [α: absorption coefficient (unit: cm ⁻¹ ), d: film thickness (unit: nm)].

<Measurement of element ratio>
The chemical compositions of the absorbing layers prepared in Examples 1-18 were analyzed by XPS method depth profile analysis using an X-ray photoelectron spectroscopy (XPS) analyzer. Tables 1 and 2 show the atomic ratio of Cr to the total amount of Cr and Si, the atomic ratio of Cr to the total amount of Cr and Al, the atomic ratio of Cu to the total amount of Cu and Si, and the total amount of Cr and Al. Tables 1 and 2 show the calculated atomic number ratios of Cr to .

<Measurement of resistivity>
The sheet resistance of the absorbing layer was measured using a super megohmmeter (Hioki Electric Co., Ltd., SM-8220) and a plate sample electrode (Hioki Electric Co., Ltd., SME-8311). Also, using this sheet resistance and the film thickness of the absorption layer, the resistivity was determined by the following formula.
Resistivity [Ω cm] = sheet resistance value [Ω/□] x film thickness of absorption layer [cm]

<Interface reflectance>
The interfacial reflectance was obtained by optical calculation at the contact surface between the transparent layer and the absorbing layer.

As shown in Tables 1 and 2, an absorption layer having a refractive index of 1.60 to 2.50 at a wavelength of 550 nm and an extinction coefficient of 0.20 to 0.50 is laminated in contact with the absorption layer. Examples 1 to 11, which include a layer structure including a transparent layer having a refractive index of 1.60 to 2.50 at a wavelength of 550 nm, have lower interface reflectance than the comparative example. From this result, it can be seen that the interface reflection of light incident on the contact surface between the transparent layer and the absorption layer is suppressed, and low reflection is realized in the example.

[Experimental example 2]
An experimental example of etching of the absorber layer is shown. Examples 19-23 are examples.
<Photoresist pattern formation>
First, a spin coater was used to apply a photoresist (OFPR800-LB manufactured by Tokyo Ohka Kogyo Co., Ltd.) on each absorption layer. Specifically, after dropping the photoresist, the substrate was first rotated at 500 rpm for 5 seconds and then at 2500 rpm for 20 seconds to apply the photoresist.

The substrate was then heated on a hot plate at 110° C. for 90 seconds to adhere the photoresist to the black film. Next, the photoresist was exposed using an exposure machine so as to obtain a desired pattern. Thereafter, the photoresist was developed for 30 seconds using a developing solution (NMD-W manufactured by Tokyo Ohka Kogyo Co., Ltd.) to remove unnecessary photoresist portions.
After that, the substrate was heated on a hot plate at 120° C. for 60 seconds to re-adhere the photoresist to the black film.

<Resist stripping ~ step measurement>
After the absorption layer on the substrate was etched by each etching method to be described later, the photoresist was peeled off and the step was measured with a stylus type step gauge. The photoresist was removed by immersing the substrate in acetone at room temperature for 3 minutes, removing the resist, immersing the substrate in isopropyl alcohol for 3 minutes, rinsing the substrate in ultrapure water, and then drying the substrate.

(Etching example 19)
The substrate was introduced into a reactive ion etching apparatus (DEM-451 manufactured by Nichiden Anelva), and the absorption film formed to a thickness of 200 nm under the conditions of Example 1 was dry-etched. As an etching gas, 40 sccm of CF ₄ gas and 10 sccm of O ₂ gas were flowed, the pressure was maintained at 27 Pa, and etching was performed for 180 seconds with a 250 W RF discharge. After stripping the photoresist, the step was measured with a stylus profilometer and found to be etched by 72 nm.
When the same etching test was performed on the absorbing film under the film forming conditions of Example 2, it was found that the film was etched by 29 nm. Further, it was found that the absorbing film under the film forming conditions of Example 5 was etched by 19 nm, and the absorbing film under the film forming conditions of Example 6 was etched by 30 nm.

(Etching example 20)
The substrate was introduced into a reactive ion etching apparatus (DEM-451 manufactured by Nichiden Anelva), and the absorption film formed to a thickness of 200 nm under the conditions of Example 1 was dry-etched. 50 sccm of C ₂ F ₆ gas was flowed as an etching gas, the pressure was maintained at 13 Pa, and etching was performed for 180 seconds with a 250 W RF discharge. After peeling off the photoresist, the step was measured with a stylus profilometer and found to be etched by 20 nm.

(Etching example 21)
The substrate was introduced into a high-density plasma etching apparatus (NE-550 manufactured by Ulvac), and the absorption film formed to a thickness of 200 nm under the conditions of Example 1 was dry-etched. 20 sccm of Cl ₂ gas and 10 sccm of BCl ₃ gas were flowed as etching gases, the pressure was maintained at 0.8 Pa, and etching was performed for 120 seconds with antenna power of 150 W and bias power of 20 W. After peeling off the photoresist, the step was measured with a stylus profilometer and found to be etched by 20 nm. Further, when the same etching test was performed on the absorbing film under the film forming conditions of Example 2, it was found that the film was etched by 63 nm.

(Etching example 22)
The absorption film was etched under the film forming conditions of Example 3 by wet etching. As an etchant, Kanto Kagaku KSMF-250 etchant (an ammonium fluoride aqueous solution containing an undisclosed additive) was used at a liquid temperature of room temperature. After etching for 180 seconds, it was visually confirmed that the absorption film was etched away. After peeling off the photoresist, the thickness was 209 nm when the step was measured with a stylus profilometer.
When the same etching test was performed on the absorbing film under the film forming conditions of Example 4, it was confirmed that the absorbing film was removed by etching in 75 seconds, and the film thickness was 194 nm.
Further, when the same etching test was performed on the absorbing film under the film forming conditions of Example 7, it was confirmed that the absorbing film was removed by etching within 60 seconds, and the film thickness was 47 nm.
Furthermore, when the same etching test was performed on the absorbing film under the film forming conditions of Example 9, it was found that the absorbing film still remained after etching for 180 seconds, but was etched by 12 nm.

(Etching example 23)
By wet etching, the absorbing film under the film forming conditions of Example 4 was etched. As an etchant, Kanto Kagaku's Al etchant (mixed solution of phosphoric acid, acetic acid and nitric acid) was heated to 35° C. and used. After etching for 17 seconds, it was visually confirmed that the absorption film was removed by etching. After peeling off the photoresist, the thickness was 188 nm when the step was measured with a stylus profilometer.

[Experimental example 3]
(Metal Cu + CuO raw material)
A mixed powder of metallic Cu powder, CuO powder and amorphous SiO ₂ powder at a molar ratio of 52.5:17.5:30, respectively, was used as a raw material to prepare a sintered body by a hot pressing method. The conditions for the hot press treatment were a heat treatment temperature of about 950° C. and a pressure of about 8 MPa. XRD measurement revealed that the obtained sintered body contained Cu ₂ O crystals and Cu crystals. Moreover, the resistivity of the sintered body was 2.8×10 ⁻⁴ Ω·cm. This sintered body was processed into a disk shape with a diameter of 152.4 mm and a thickness of 5 mm, and then bonded to a copper backing plate to prepare a sputtering target.

(Cu metal raw material)
A sintered body was produced by a hot press method using a mixed powder of metal Cu powder and amorphous SiO ₂ powder at a molar ratio of 70:30, respectively, as a raw material. XRD measurement revealed that the obtained sintered body contained Cu crystals. Moreover, the resistivity of the sintered body was 4.7×10 ⁻⁵ Ω·cm.

(CuO raw material)
A mixed powder of CuO powder and amorphous SiO ₂ powder at a molar ratio of 70:30, respectively, was used as a raw material to prepare a sintered body by a hot press method. Also, the resistivity of the sintered body was greater than 1×10 ⁻³ Ω·cm.

From the above, it was found that the atomic number ratio of Cu:Si = 70:30 and that a sputtering target exhibiting conductivity could be produced.

Although the present invention has been described in detail with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. This application is based on a Japanese patent application (Japanese Patent Application No. 2021-011395) filed on January 27, 2021, the entirety of which is incorporated by reference. Also, all references cited herein are incorporated in their entirety.

Reference Signs List 1 optical thin film laminate 2 absorption layer 3 transparent layer 6 substrates 7 and 8

light emitting elements

9 and 10 electric circuit
15, 16 thin film transistor array

Claims

comprising a substrate and an optical thin film layer;
The optical thin film layer includes an absorption layer having a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm, and a wavelength of 550 nm laminated in contact with the absorption layer. and a transparent layer having a refractive index of 1.60 to 2.50.
The optical thin film laminate according to claim 1, wherein the absorption layer has a physical thickness of 200 to 500 nm.
3. The optical thin film laminate according to claim 1, wherein the resistivity of said absorption layer is 1×10 −1 Ωcm or more.
The optical thin film laminate according to any one of claims 1 to 3, wherein the absorption layer contains at least one selected from oxides, nitrides, oxynitrides and oxycarbides containing at least two kinds of metal cations. body.
The optical thin film according to any one of claims 1 to 4, wherein the absorption layer contains at least one element selected from the group consisting of Cr, Mn, Fe, Co, Ni, Cu, Ru and Ag. laminate.
6. The optical system according to claim 5, wherein the absorbing layer contains Cr and Si, and the atomic number ratio of Cr to the total amount of Cr and Si in the absorbing layer is in the range of 0.10 to 0.70. Thin film laminate.
6. The optical system according to claim 5, wherein the absorbing layer contains Cr and Al, and the atomic ratio of Cr to the total amount of Cr and Al in the absorbing layer is in the range of 0.10 to 0.50. Thin film laminate.
6. The optical system according to claim 5, wherein the absorption layer contains Cu and Si, and the atomic ratio of Cu to the total amount of Cu and Si in the absorption layer is in the range of 0.10 or more and 0.95 or less. Thin film laminate.
6. The optical system according to claim 5, wherein the absorption layer contains Cu and Al, and the atomic ratio of Cu to the total amount of Cu and Al in the absorption layer is in the range of 0.30 or more and 0.95 or less. Thin film laminate.
The optical thin film laminate according to any one of claims 1 to 9, wherein the absorption layer can be patterned by etching.
comprising a substrate and an optical thin film layer;
A light-emitting device in which the optical thin film layer includes at least an absorption layer, a lower electrode, a light-emitting layer and an upper electrode, and extracts light above a substrate,
the lower electrode is laminated in contact with the absorption layer;
The absorption layer has a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm,
A light emitting device comprising the optical thin film laminate according to any one of claims 1 to 10, wherein said lower electrode is a transparent layer having a refractive index of 1.60 to 2.50 at said wavelength of 550 nm.
comprising a substrate and an optical thin film layer;
the optical thin film layer includes an absorption layer between a metal wire and an insulating layer laminated on top of the metal wire;
The absorption layer is laminated so as to be in contact with the metal wiring and the insulating layer,
The absorption layer has a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm,
An electric circuit comprising an optical thin film laminate according to any one of claims 1 to 10, wherein said insulating layer is a transparent layer having a refractive index of 1.60 to 2.50 at a wavelength of 550 nm.
including a substrate and a plurality of thin film transistors;
the thin film transistor includes a semiconductor layer, an absorption layer, and an insulating layer disposed between the semiconductor layer and the absorption layer;
The insulating layer is laminated so as to be in contact with the absorbing layer,
The absorption layer has a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm,
A thin film transistor array comprising the optical thin film laminate according to any one of claims 1 to 10, wherein said insulating layer is said transparent layer having a refractive index of 1.60 to 2.50 at a wavelength of 550 nm.
A method for manufacturing an optical thin film laminate comprising forming an optical thin film layer on a substrate,
The formation of the optical thin film layer includes:
forming an absorption layer having a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm; A method for producing an optical thin film laminate, comprising forming a transparent layer having a refractive index of 1.60 to 2.50.
A sputtering target material used in the method for producing an optical thin film laminate according to claim 14,
A sputtering target material for forming the absorption layer having a refractive index of 1.60 to 2.50 and an extinction coefficient of 0.20 to 0.50 at a wavelength of 550 nm by sputtering.