Laminate and indicator

Abstract

To provide a laminate having a color change layer configured to change a color tone thereof by detecting at least one kind selected from a group consisting of plasma, ozone, ion, ultraviolet light and radical-containing gas, and a substrate layer, the laminate improving a color change sensitivity in the color change layer, and also to provide a temperature indicator capable detecting a temperature distribution on a surface of a processing target by a simple method.SOLUTION: A laminate includes a color change layer having a film density of 0.20 to 1.00 g / cm3 and a substrate layer. The color change layer includes a structure having an internal space communicating with an opening part at a surface. The internal space contains a detection agent including at least one kind of pigment that changes a color tone when at least one kind selected from a group consisting of plasma, ozone, ion, ultraviolet light and radical-containing gas is detected.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a laminate and an indicator. [Background technology]

[0002] In manufacturing electronic devices, it is necessary to uniformly perform treatment with at least one selected from the group consisting of plasma, ozone, ions, ultraviolet light, and radical-containing gas (hereinafter sometimes referred to as "plasma, etc."). It is also necessary to perform treatment so that the thermal history of each electronic device is uniform. For example, it is important that treatment with plasma, etc. in the pre-process of semiconductor chip manufacturing is performed uniformly within the wafer surface, and that in-plane uniformity is maintained. If the in-plane uniformity is impaired, the performance of each semiconductor chip formed on the semiconductor wafer will vary, affecting the yield. For this reason, confirmation of the uniformity of processing by plasma or the like is essential when designing each electronic device manufacturing apparatus and when managing the manufacturing process using said apparatus. There are various known methods for evaluating the uniformity of plasma processing, including a method using various indicators to directly measure the in-plane distribution of each process.

[0003] Patent Document 1 describes an indicator in which an ink containing a dye, a specific surfactant, and a nonionic surfactant is applied to a substrate. By placing this indicator in a reaction chamber or the like, it is possible to detect the end point of a treatment such as plasma. Patent Document 2 describes an indicator that includes a color-changing layer formed from ink that changes color or loses color upon reaction with plasma, etc. This indicator has the same shape as the substrate used in electronic device manufacturing equipment, and makes it possible to confirm the uniformity of treatment with plasma, etc. Patent Document 3 describes a plasma indicator in which a dye is contained in pores formed by anodization. Patent Document 4 describes a plasma indicator having a color-changing layer in the pores of a porous body, the color-changing layer containing a dye that changes color or loses color upon reaction with plasma or the like.

[0004] The indicators described in Patent Documents 1 to 3 allow the progress of plasma processing or the like to be visually confirmed in a reaction chamber, but the sensitivity or the like must be appropriately adjusted. In addition, depending on the processing conditions, etc., some of the components of the indicator may scatter and contaminate the object to be processed in the plasma processing or the inside of the chamber. In particular, the indicators often contain substances containing metal atoms or halogen atoms, and there is a risk of contamination by the metal atoms or halogen atoms. The indicator described in Patent Document 4 has a reduced content of metal atoms and halogen atoms to avoid contamination, but there is a demand for improving the color change sensitivity of the color-changing layer. Furthermore, in order to confirm the processing accuracy of the plasma processing or the like, there has been a demand for a temperature indicator that can detect the temperature distribution on the surface of the workpiece in a simple manner. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2015-013982 A [Patent Document 2] International Publication No. 2015 / 025699 [Patent Document 3] International Publication No. 2018 / 128123 [Patent Document 4] JP 2020-180963 A Summary of the Invention [Problem to be solved by the invention]

[0006] The problem to be solved by the present invention is to provide a laminate having a base layer and a color-changing layer that changes color upon detecting at least one kind selected from the group consisting of plasma, ozone, ions, ultraviolet light, and radical-containing gases, in which the color-changing sensitivity of the color-changing layer is improved. Another problem to be solved by the present invention is to provide a temperature indicator capable of detecting the temperature distribution on the surface of a workpiece in a simple manner.

[0007] As a result of investigations aimed at solving the above problems, the present inventors have found that the above problems can be solved by forming a laminate having a specific structure and using this as an indicator. Specifically, the following are included: [1] Film density is 0.20 to 1.00 g / cm 3 and a base layer, wherein the color-changing layer has a structure having an internal space communicating with an opening on the surface, and the internal space contains a detection agent including at least one dye that changes color upon detecting at least one kind of ion selected from the group consisting of plasma, ozone, ions, ultraviolet light, and radical-containing gas. [2] The density of the discoloration layer is 0.30 to 0.50 g / cm 3 The laminate according to [1], [3] Color difference ΔE when the discolored layer of the laminate is treated for 5 minutes with plasma using CF4:O2=1:1 gas as the raw material gas. * The laminate according to [1] or [2], wherein ab is 10 or more. [4] The laminate according to any one of [1] to [3], which has a concealing layer between the color-changing layer and the base layer. [5] A temperature indicator used for detecting a temperature distribution occurring during plasma irradiation, comprising the laminate according to any one of [1] to [4]. Effect of the Invention

[0008] The present invention provides a laminate having a base layer and a color-changing layer that changes color upon detecting at least one type selected from the group consisting of plasma, ozone, ions, ultraviolet light, and radical-containing gas, in which the color-changing sensitivity of the color-changing layer is improved. The present invention also provides a temperature indicator that can detect the temperature distribution on the surface of a workpiece in a simple manner. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a graph showing the relationship between temperature, color difference ΔE*ab, and plasma exposure time in the temperature indicator of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] [Laminate] The laminate of the present invention has a film density of 0.20 to 1.00 g / cm 3 and a base layer, wherein the color-changing layer has a structure having an internal space communicating with the openings on the surface, and the internal space contains a sensing agent including at least one dye that changes color upon detecting at least one kind of ion selected from the group consisting of plasma, ozone, ions, ultraviolet light, and radical-containing gases. In this specification, the terms plasma, ozone, ions, ultraviolet rays and radical-containing gas are defined as follows.

[0011] <Plasma> The plasma refers to plasma generated by applying an AC voltage, a DC voltage, a pulse voltage, high frequency, microwaves, or the like using a plasma generating gas, and includes both low-pressure plasma and atmospheric pressure plasma. As the plasma generating gas, for example, at least one gas selected from the group consisting of oxygen, nitrogen, hydrogen, fluorine, chlorine, helium, neon, argon, silane, ammonia, sulfur bromide, water vapor, nitrous oxide, tetraethoxysilane, carbon tetrafluoride, trifluoromethane, carbon tetrachloride, silicon tetrachloride, sulfur hexafluoride, titanium tetrachloride, dichlorosilane, trimethylgallium, trimethylindium, trimethylaluminum, air, and carbon dioxide can be used. Examples of the plasma include plasma generated in a plasma processing apparatus (an apparatus that performs plasma processing by applying an AC voltage, a DC voltage, a pulse voltage, a high frequency wave, a microwave, or the like in an atmosphere containing a gas for generating plasma) used in a film formation process, an etching process, an ashing process, an impurity addition process, a cleaning process, and the like during the manufacture of an electronic device.

[0012] <Ozone> Examples of ozone include ozone generated when oxygen is exposed to ultraviolet light, ozone generated by discharging in an oxygen-containing gas such as dry air or in oxygen gas, ozone generated by electrolysis of dilute sulfuric acid, etc. For example, ozone may be ozone generated in an ozone treatment device used in a film formation process, an ashing process, a cleaning process, etc. during the manufacture of electronic devices, or ozone generated during the generation of photochemical smog. <Aeon> Examples of ions include those generated by applying high-frequency power to gases such as argon, methane, acetylene, etc. For example, ions may be those used in sputtering, which is performed by accelerating ionized argon in an electric field in a vacuum and irradiating and colliding it with a metal surface or the like to remove surface atoms by utilizing the property of hardly causing a chemical reaction, ion beam etching, doping, etc.

[0013] <Ultraviolet rays> Ultraviolet rays refer to electromagnetic waves with wavelengths of about 1 to 400 nm, and include near ultraviolet rays, far ultraviolet rays, vacuum ultraviolet rays, and extreme ultraviolet rays. For example, ultraviolet rays can be generated from ultraviolet irradiation devices including mercury lamps and LEDs, or can be obtained from ultraviolet treatment devices used in photolithography, ashing, cleaning, and other processes during the manufacture of electronic devices.

[0014] <Radical-containing gas> The radical-containing gas is, for example, hydrogen gas passed through a Ta thin tube heated to 2100 K by electron beam bombardment, and the degree of vacuum is set to 1.0×10 -4 Torr~1.0×10 -6 Torr. Furthermore, for example, the radical-containing gas can be obtained by a radical-containing gas treatment apparatus used in a film-forming process, an etching process, an ashing process, a cleaning process, or the like during the manufacture of electronic devices.

[0015] <Discolored layer> The change in color tone of the color-changing layer occurs when the dye comes into contact with plasma or the like, causing one or more color tone changes, such as discoloration, decolorization, or color development. In the discoloration layer of the present invention, the detecting agent is uniformly present within the surface of the discoloration layer, which allows not only simple detection of plasma, etc., but also easy visual detection of the in-surface uniformity during treatment with plasma, etc. and the temperature distribution during treatment with plasma, etc.

[0016] (structure) The structure constituting the color-changing layer of the present invention is made of at least one material selected from the group consisting of organic materials, inorganic materials, and organic-inorganic composite materials, and has an internal space communicating with the openings on the surface. The color tone may be any color tone that allows the change in the pigment to be recognized, and is preferably transparent, colored transparent, white, or pale color. Examples of the structure that can be used include a porous body having an internal space communicating with the openings on the surface, a body in which at least one of holes, recesses, protrusions, and cracks is provided by an appropriate means to form an internal space that communicates with the openings on the surface, a composition in which a porous substance is disposed on the surface, etc. Of these, a porous body having an internal space communicating with the openings on the surface is preferably used. The material constituting the structure may contain components such as an extender, if necessary. When the content of each metal atom in the laminate is less than 5.0 ppm by mass and / or the content of each halogen atom is less than 30 ppm by mass, it is preferable to use a structure that does not contain metal atoms and / or halogen atoms. In the present invention, the structure has a function of hiding the color of the wafer, thereby increasing the color change sensitivity. In addition, by using the structure, it is possible to measure the color change of the detecting agent over time according to the penetration degree of plasma or the like, and the color change proportional to the amount or strength of exposure to plasma or the like.

[0017] The porous body having an internal space communicating with the open pores on the surface may be, for example, any of an inorganic porous body, an organic porous body, and an organic-inorganic composite porous body. Examples of inorganic porous bodies include, but are not limited to, at least one selected from the group consisting of metal porous bodies, silica-based porous bodies, alumina-based porous bodies, zeolite-based porous bodies, silicate-based porous bodies, mesoporous porous bodies, glass porous bodies, ceramic porous bodies, pumice, and porous bodies such as metal oxides and metal hydroxides.

[0018] Examples of organic porous bodies include, but are not limited to, at least one selected from the group consisting of resin porous bodies (porous films, porous polymer beads, etc.), nonwoven fabrics, knitted fabrics, woven fabrics, paper, activated carbon, fullerenes, carbon nanotubes, etc. The resin constituting the resin porous body is not particularly limited, and may be a synthetic resin or a commercially available resin. For example, at least one selected from the group consisting of polyimide resin, polyamideimide resin, polybenzimidazole resin, polyamide resin, polyolefin resin, polyurethane resin, melamine resin, polyester resin, and polycarbonate resin can be mentioned. In particular, when a heat-resistant polymer such as polyamideimide resin, polyimide resin, polybenzimidazole resin, or polyamide resin is used as the structure, a laminate with excellent heat resistance is obtained, so that an indicator that can be used under high temperature conditions and has strong resistance to plasma treatment can be constituted.

[0019] In the present invention, when the content of each metal atom in the laminate is less than 5.0 ppm by mass and / or the content of each halogen atom is less than 30 ppm by mass, it is preferable to use an organic porous body, in particular a resin porous body, as the structure constituting the color-change layer. In order to prevent contamination of the inside of electronic device manufacturing equipment with metal atoms and / or halogen atoms, it is preferable to use an organic porous body, in particular a resin porous body, as the structure constituting the color-change layer.

[0020] (Detection agent) The detecting agent contains at least one dye that changes color upon detecting plasma etc. The detecting agent may contain other components in addition to the dye as necessary. In the present invention, the detecting agent is preferably composed of a compound that does not contain metal atoms, particularly a dye compound that does not contain atoms other than carbon, hydrogen, oxygen, and nitrogen. In addition, it is preferable to prevent impurities such as metal atoms and halogen atoms from being mixed into the detecting agent by thoroughly purifying the components thereof and not using metal tools during preparation. This allows the content of each metal atom in the laminate to be less than 5.0 ppm by mass, and when the laminate is used as an indicator for detecting plasma, etc., contamination in an electronic device manufacturing apparatus, particularly contamination by metal atoms and halogen atoms, can be effectively prevented. The detecting agent may contain components other than the dye, within a range that does not impair the effect of the color change caused by the dye, for the purpose of adjusting the sensitivity, improving the visibility of the color difference before and after detection, etc. Examples of such components include at least one selected from the group consisting of dyes whose color does not change even when plasma or the like is detected, resins and / or resin precursors, surfactants, fillers, color change retarders, color change promoters, solvents, leveling agents, antifoaming agents, and other additives.

[0021] {pigment} The dye that changes color upon detecting plasma or the like is not particularly limited as long as it exhibits a behavior in which the color tone changes when exposed to plasma or the like. For example, at least one selected from the group consisting of dyes known as colorants, preferably dyes and pigments, that change color upon detecting plasma or the like can be used. For example, it is preferable to use at least one selected from the group consisting of anthraquinone dyes, perylene dyes, methine dyes, azo dyes (monoazo dyes, diazo dyes, triazo dyes, polyazo dyes, azoic dyes (diazo components), azoic dyes (coupling components), etc.), phthalocyanine dyes, triarylmethane dyes, xanthene dyes, oxazine dyes, indanthrene dyes, food dyes, and perinone dyes. Preferably, the dye is at least one selected from the group consisting of anthraquinone-based dyes, perylene-based dyes, methine-based dyes, azo-based dyes, phthalocyanine-based dyes, triarylmethane-based dyes, xanthene-based dyes, indanthrene-based dyes, and edible dyes, and particularly preferably, the dye is at least one selected from the group consisting of anthraquinone-based dyes, perylene-based dyes, methine-based dyes, indanthrene-based dyes, and azo-based dyes.

[0022] Specific examples of these dyes include CIAzoic Coupling Component 3, 16, CIBasic Green 4, CIMordant Red 27, CISolvent Black 3, CISolvent Blue 35, CISolvent Red 18, 24, 27, 49, 52, CISolvent Violet 14, CISolvent Yellow 29, CIVat Black 8, 9, 25, 27, 29, CIVat Brown 1, 3, 25, 44, CIVat Green 8, CIVat Orange 13, 15, CIVat Red 10, 13, 15, CIVat Yellow 10, 20, Lumogen F IR 788, Lumogen F Orange 240, Lumogen F Pink 285, Lumogen F Red 300, 305, 339, Lumogen F Violet 570, Lumogen F Yellow 083,170, Iketon Violet extra, Oil Peacock Blue, and Oil Brown BG extra.

[0023] In the present invention, the color change sensitivity of the detecting agent and the color development and color change of the color change layer can be controlled by selecting the type of dye (molecular structure, etc.), using a mixture of multiple dyes, adjusting the dye content, etc. The content of the detecting agent in the color-changing layer may be appropriately adjusted depending on the type of detecting agent, color change sensitivity, product form, characteristics of the structure, and the like. For example, the detection agent in the color-changing layer is, for example, 0.01 mass % or more, preferably 0.05 mass % or more, more preferably 0.10 mass % or more, and for example, 20.0 mass % or less, preferably 10.0 mass % or less, more preferably 1.0 mass % or less, and even more preferably 0.7 mass % or less. If the color-changing layer contains a large amount of detection agent, the color-changing sensitivity tends to decrease. If the amount of detection agent is too small, the color-changing sensitivity also tends to decrease.

[0024] (Film thickness) The film thickness of the color-changing layer is not particularly limited as long as it exhibits a detection function, and can be appropriately optimized according to the application, desired characteristics, etc. From the viewpoint of color-changing sensitivity, it is, for example, less than 10 μm, preferably 9.5 μm, more preferably 9 μm or less, for example, 0.5 μm or more, preferably 1 μm or more. If the film thickness of the color-changing layer is 10 μm or more, the color-changing sensitivity may be insufficient when the processing time of plasma or the like is short or the output of plasma or the like is weak. Also, if it is less than 0.5 μm, the color of the color-changing layer may be insufficient, resulting in a narrow color-changing range.

[0025] (film density) The laminate of the present invention has a film density of the color-changing layer of 0.20 to 1.00 g / cm 3 Preferably, it is 0.25 g / cm 3 More preferably, 0.30 g / cm 3 or more, preferably 0.70 g / cm 3 Less than or equal to 0.50 g / cm 3 More preferably, 0.42 g / cm 3 The following is the result. The film density of the discoloration layer is 0.20g / cm 3 If the film density of the color-change layer is less than 1.00 g / cm, it is difficult to form the color-change layer, and the film strength of the color-change layer is insufficient. 3 If the temperature exceeds this range, the penetration of plasma and the like into the color-changing layer is hindered, the decomposition of the detecting agent is not sufficiently carried out, and the color-changing sensitivity of the color-changing layer decreases.

[0026] The film density can be adjusted by adjusting the porosity of the structure that constitutes the color-change layer. For example, (1) Porosification by chemical means such as using a pore-forming agent (for example, porosification using a foaming agent, porosification using gas generated during molding, porosification in which the pore-forming agent is removed after molding by dissolving, vaporizing, sublimating, etc., porosification by phase separation using mixed solvents with different solubilities or boiling points, etc.) (2) Porosity due to stretching (3) Porosity due to fusion of powder particles (4) When making a porous material porous by mechanical means such as perforation, there is a method for adjusting the porosity.

[0027] In the present invention, in the means (1) described above, a means for adjusting the type and amount of a good solvent in which the resin constituting the structure and the resin or its precursor have a high solubility, and a means for adjusting the type and amount of a poor solvent in which the resin has a low solubility, etc., are preferably used. When one or more types selected from the group consisting of polyimide-based resins, polyamideimide-based resins, polybenzimidazole-based resins, etc. are used as the resin constituting the structure, one or more types of nitrogen-containing polar solvents selected from the group consisting of amide-based solvents, urea-based solvents, etc. are preferably used as the good solvent, and one or more types of organic solvents selected from the group consisting of ether-based solvents, hydrocarbon-based solvents, ester-based solvents, etc. are preferably used as the poor solvent. Examples of the amide solvent include N-methyl-2-pyrrolidone (NMP), N-ethyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide (DMAc), etc. Examples of the urea solvent include tetramethylurea, dimethylethyleneurea, etc. Examples of ether solvents include diglyme, triglyme, tetraethylene glycol dimethyl ether, triethylene glycol dimethyl ether, diethylene glycol dimethyl ether, tripropylene glycol dimethyl ether, dipropylene glycol dimethyl ether, tetrahydrofuran, and dioxane. Examples of hydrocarbon solvents include n-hexane, cyclohexane, benzene, toluene, xylene, and petroleum ether. Examples of ester solvents include ethyl carbitol acetate, butyl carbitol acetate, dimethyl succinate, diethyl succinate, dimethyl glutarate, diethyl glutarate, dimethyl adipate, and diethyl adipate. In the present invention, a good solvent for a resin is a solvent that dissolves 0.1 g or more of the resin in 100 g of the solvent at 25° C. A poor solvent for a resin is a solvent that dissolves less than 0.1 g of the resin in 100 g of the solvent at 25° C.

[0028] In the present invention, when the total amount of the resin, the good solvent, and the poor solvent is taken as 100 mass %, the amounts of the resin, the good solvent, and the poor solvent used are preferably as follows, respectively. Resin: for example, 7.0% by mass or more, preferably 8.0% by mass or more, and for example, 15.0% by mass or less, preferably 11.0% by mass or less Good solvent: for example, 10.0% by mass or more, preferably 15.0% by mass or more, and for example, 50.0% by mass or less, preferably 40.0% by mass or less Poor solvent: for example, 35.0% by mass or more, preferably 40.0% by mass or more, and for example, 80.0% by mass or less, preferably 70.0% by mass or less If the amount of the resin exceeds 15.0% by mass, it is difficult to adjust the porosity and the color change range may be narrowed, whereas if the amount of the resin is less than 7.0% by mass, the porous film may not be formed and the color change sensitivity may be deteriorated. If the amount of the good solvent exceeds 50.0% by mass, it may be impossible to form a porous film, and if the amount of the good solvent is less than 10.0% by mass, unevenness may occur and phase separation may occur. If the amount of the poor solvent exceeds 80.0% by mass, unevenness may occur and phase separation may occur, whereas if the amount of the poor solvent is less than 35.0% by mass, a porous membrane may not be formed.

[0029] In the present invention, a varnish containing a resin and an organic solvent may be used, and a good solvent and a poor solvent may be mixed with the resin varnish. The resin varnish may have a resin content of 10 to 20 mass%, preferably 10 to 15 mass%. In this case, when the total amount of the resin varnish, the good solvent, and the poor solvent is taken as 100 mass%, it is preferable that the amounts of the resin, the good solvent, and the poor solvent are as follows: Resin varnish: for example, 60% by mass or more, preferably 70% by mass or more, and for example, 90% by mass or less, preferably 80% by mass or less Good solvent: for example, 1% by mass or more, preferably 10% by mass or more, and for example, 20% by mass or less, preferably 15% by mass or less Poor solvent: for example, 1% by mass or more, preferably 10% by mass or more, for example, 20% by mass or less, preferably 15% by mass or less If the amount of the resin exceeds 90% by mass, it is difficult to adjust the porosity and the color change range may be narrowed, whereas if the amount of the resin is less than 60% by mass, the porous film may not be formed and the color change sensitivity may be deteriorated. If the amount of the good solvent exceeds 20% by mass, it may be impossible to form a porous film, and if the amount of the good solvent is less than 1% by mass, unevenness may occur and phase separation may occur. If the amount of the poor solvent exceeds 20% by mass, unevenness may occur and phase separation may occur, whereas if the amount of the poor solvent is less than 1% by mass, a porous membrane may not be formed.

[0030] In the present invention, the film density is 0.20 to 1.00 g / cm 3 As the structure constituting the color-changing layer, it is preferable to use a polyimide-based resin porous body obtained from a resin solution containing a polyimide-based resin precursor, an amide-based solvent (a good solvent for the polyimide-based resin precursor), and an ether-based solvent (a poor solvent), or a polyamideimide-based resin porous body obtained from a resin solution containing a polyamideimide-based resin precursor, an amide-based solvent (a good solvent for the polyamideimide-based resin precursor), and an ether-based solvent (a poor solvent).

[0031] (color difference ΔE * ab) The color difference ΔE when the color-changing layer of the laminate of the present invention is treated for 5 minutes with plasma using CF4:O2=1:1 gas as the raw material gas. * It is preferred that ab is 10 or greater. Color difference ΔE * ab is L * a * b * The color difference in color space is the L of the discolored layer before plasma treatment. * , a * and b * and L of the discolored layer after 5 minutes of plasma treatment. * , a* and b * Measure each with a colorimeter and calculate the difference ΔL * , Δa * , Δb * Calculate the following formula: ΔE * ab = [(ΔL * ) 2 +(Δa * ) 2 +(Δb * ) 2 ] 1 / 2 is required from. The plasma treatment conditions were the same as those described in the section [Examples]. ΔE * ab is preferably 10 or more, more preferably 15 or more, further preferably 20 or more, and most preferably 30 or more. ΔE * When ab is 10 or more, color change can be reliably confirmed by visual inspection, and the color change sensitivity is excellent.

[0032] <Base material layer> The substrate layer is not particularly limited as long as it can support the color-changing layer. At least one material selected from the group consisting of inorganic materials, organic materials, and composites thereof can be used. The thickness of the base layer is not particularly limited as long as it can reliably support the color-changing layer, and is, for example, 0.01 mm or more, preferably 0.1 mm or more, and, for example, 10 mm or less, preferably 1 mm or less.

[0033] The inorganic material constituting the substrate layer may be, for example, at least one material selected from the group consisting of metals or alloys, semiconductor materials, ceramics, glass, quartz, sapphire, and concrete. The organic material constituting the base layer may be, for example, at least one selected from the group consisting of resin, paper, fibers (nonwoven fabric, knitted fabric, woven fabric, other fiber sheets), leather, and the like. Of these, it is preferable to use at least one material selected from the group consisting of semiconductor materials, glass, sapphire, resin, and paper as the base material layer.

[0034] Examples of the semiconductor material include, but are not limited to, at least one selected from the group consisting of metal oxides and metal oxynitrides such as silicon (Si), germanium (Ge), tellurium (Te), zinc oxide (ZnO), gallium arsenide (GaAs), gallium nitride (GaN), gallium oxide (Ga2O3), aluminum nitride (AlN), indium nitride (InN), silicon carbide (SiC), aluminum gallium nitride (AlGaN), indium gallium nitride (InGaN), and indium aluminum gallium nitride (InAlGaN). Examples of the resin include at least one selected from the group consisting of polyethylene terephthalate, polyethylene naphthalate, polyethylene-based resins, polypropylene-based resins, polynorbornene-based resins, polyamide-based resins, polyamideimide-based resins, polyimide-based resins, polycarbonate-based resins, and acrylic-based resins.

[0035] When the laminate is used as an indicator in a manufacturing device for each product, examples of materials constituting the base layer include the following. Indicators for semiconductor manufacturing equipment: silicon, gallium arsenide, silicon carbide, etc. Indicators for LED manufacturing equipment: Sapphire, Gallium Nitride, Gallium Arsenide, etc. Indicators for semiconductor laser manufacturing equipment: Gallium arsenide, gallium nitride, sapphire, etc. Indicators for power device manufacturing equipment: silicon carbide, gallium nitride, silicon, etc. Indicators for solar cell manufacturing equipment: silicon, glass, germanium, etc. Indicators for LCD manufacturing equipment: silicon, glass, germanium, etc. Indicators for organic EL display manufacturing equipment: glass, etc. General-purpose / simple indicators: resin, paper, glass, etc.

[0036] <Hidden Layer> In the present invention, a concealing layer may be provided between the color-changing layer and the substrate layer. The concealing layer is a layer for preventing the color tone of the base layer from affecting the color tone of the color-changing layer and the observation of the discoloration of the color-changing layer, etc. In addition, the color tone of the concealing layer is preferably a color tone that does not affect the color tone of the color-changing layer and the observation of the discoloration of the color-changing layer, etc. The components constituting the concealing layer are not particularly limited. For example, it may be composed of the same components as the structure constituting the color-changing layer. In this case, the color tone of the concealing layer and the color tone of the color-changing layer after discoloration are similar, so that the discoloration of the color-changing layer can be observed more clearly. Furthermore, even if the components of the concealing layer are different from those of the structure constituting the color-changing layer, it is advantageous to consider the color tone and make it similar to the color tone of the color-changing layer after discoloration. Furthermore, by forming the concealing layer as a concealing layer having a primer function, the adhesion between the base layer and the color-changing layer can be improved. The thickness of the concealing layer is not particularly limited, but is, for example, 5 μm or more, preferably 10 μm or more, more preferably 15 μm or more, and is, for example, 35 μm or less, more preferably 30 μm or less.

[0037] <Layer configuration> The laminate of the present invention may have other layers in addition to the color-changing layer, the substrate layer and the concealing layer. The order of lamination of the color-changing layer, base layer, concealing layer and other layers is not particularly limited, so long as the concealing layer is provided between the color-changing layer and the base layer. The color-changing layer, the concealing layer, and the other layers may each be formed as one layer, or as multiple layers. Also, the same layers may be adjacent to each other. In this case, the same layers may have the same composition or different compositions.

[0038] The color-changing layer, the concealing layer, and other layers may be formed on the entire surface of the base layer or each layer, or may be formed partially. In these cases, the color-changing layer and other layers can be formed so that at least one color-changing layer is exposed to plasma or the like in part or in whole, in order to ensure a change in color tone of the color-changing layer in particular. The laminate of the present invention may be formed by combining the color-changing layer, the concealing layer, and other layers in any combination, as long as the completion of each of the above-mentioned treatments and the in-plane uniformity can be confirmed. The color-changing layer may not overlap with other layers, or may overlap with other layers. The laminate of the present invention may be configured such that at least one of letters, designs, and symbols appears due to the change in color of the color-changing layer, in order to notify the user that the color tone of the color-changing layer has changed due to plasma, etc. The letters, designs, and symbols include all information that notifies the user of a color change, and these letters, etc. can be designed appropriately depending on the purpose of use, etc.

[0039] <Shape> The laminate of the present invention may have any shape depending on the application. For example, the laminate can be made to have the same or nearly the same shape as a substrate used in an electronic device manufacturing apparatus and used as a so-called dummy substrate, making it possible to easily detect whether the above-mentioned processing is being performed uniformly over the entire substrate.

[0040] <Content of each metal atom in the laminate> The content of each metal atom in the laminate is preferably less than 5.0 ppm by mass, more preferably less than 1.0 ppm by mass, even more preferably less than 0.5 ppm by mass, even more preferably less than 0.1 ppm by mass, most preferably less than 1.0 ppt by mass, and even more preferably less than 0.5 ppt by mass. Here, "metal atom" means an atom other than hydrogen, carbon, nitrogen, oxygen, silicon, fluorine, chlorine, bromine, iodine and rare gases. In order to make the content of each metal atom in the laminate less than 5.0 ppm by mass, all materials contained in the laminate are made to be free of metal atoms. In addition, all components related to the laminate (including solvents, etc.) are made to be free of metal atoms, and metal atom-containing substances contained as impurities are removed by purification. Furthermore, it is preferable not to use tools, etc. that may cause contamination of metal atoms in the manufacturing process. In the present invention, the content of each metal atom in all layers, including the discoloration layer, base layer, and concealing layer, is measured by ICP-MS (Inductively Coupled Plasma Mass Spectrometry) or the like, and if each is less than 5.0 ppm by mass, the content of each metal atom in the laminate is determined to be less than 5.0 ppm by mass. Also, an indicator including the laminate of the present invention is introduced into a treatment device together with a material to be treated, and treatment such as plasma treatment is carried out. After that, each metal atom on the surface of the material to be treated introduced into the treatment device is recovered with hydrofluoric acid or the like, and the content of each metal atom is measured by ICP-MS or the like. If each is less than 5.0 ppm by mass, it is determined that each metal atom in the laminate is less than 5.0 ppm by mass. By making the content of each metal atom in the laminate less than 5.0 ppm by mass, when the laminate is used as an indicator in an electronic device manufacturing equipment, it is possible to prevent contamination of the treated object and the inside of the manufacturing equipment with metal atoms. This makes it possible to obtain an indicator that can be used in the manufacturing process of semiconductor electronic devices (particularly the etching process in the first half of the process) where the presence of metal atoms is particularly undesirable.

[0041] <Content of each halogen atom> The content of each halogen atom in the laminate is preferably less than 30 ppm by mass, more preferably less than 5 ppm by mass, even more preferably less than 1 ppm by mass, still more preferably less than 0.5 ppm by mass, and most preferably less than 1.0 ppt by mass. In order to make the content of each halogen atom in the laminate less than 30 ppm by mass, it is preferable that all materials contained in the laminate are composed of materials that do not contain halogen atoms. It is also preferable to use all components (including solvents, etc.) related to the laminate that do not contain halogen atoms and to remove halogen-atom-containing substances contained as impurities by purification. Furthermore, it is preferable to use a method, etc. that does not use tools, etc. that may cause contamination of halogen atoms in the manufacturing process. In the present invention, the content of each halogen atom in each material used in all layers, including the color-changing layer, base layer, and concealing layer, is measured by combustion ion chromatography or ICP-MS (Inductively Coupled Plasma Mass Spectrometry) or the like, and if each is less than 30 ppm by mass, the content of each halogen atom in the laminate is deemed to be less than 30 ppm by mass. Also, an indicator including the laminate of the present invention is introduced into a treatment device together with a material to be treated, and a treatment such as plasma treatment is carried out. Thereafter, halogen atoms present on the surface of the material to be treated introduced into the treatment device are collected and the content of each halogen atom is measured by combustion ion chromatography, ICP-MS, or the like, and if each is less than 30 ppm by mass, the content of each halogen atom in the laminate is determined to be less than 30 ppm by mass. By making the content of each halogen atom in the laminate less than 30 ppm by mass, when the laminate is used as an indicator in an electronic device manufacturing equipment, it is possible to prevent contamination of the treated material and the inside of the manufacturing equipment with halogen atoms. This makes it possible to obtain an indicator that can be used in the manufacturing process of semiconductor electronic devices (particularly the etching process in the first half of the process) where the presence of halogen atoms is particularly undesirable.

[0042] <Method of manufacturing laminate> The method for producing the laminate is not particularly limited, and examples thereof include the following methods (1) to (5). (1) A method in which a discoloration layer-forming material containing a component that forms a structure having an internal space that communicates with the openings on the surface and a detector agent is applied onto a base layer, and then dried and heated to form a discoloration layer with a specified film density and a specified structure (porosity), resulting in a laminate. (2) A method in which a structure having an internal space communicating with the openings on the surface is provided on a base layer, and then a detecting agent or a detecting agent solution is applied, impregnated, sprayed, etc., to retain the detecting agent in the internal space to form a laminate. (3) A method in which a structure having an internal space communicating with the openings on the surface is formed, and a detecting agent or a detecting agent solution is applied, impregnated or sprayed onto the structure to retain the detecting agent within the internal space, and then the structure is fixed onto a base layer. (4) A method in which a composition containing a component for forming a structure, a component for forming an internal space in the structure that communicates with the openings on the surface, and the detecting agent is provided on a base layer, and then a treatment is performed to form an internal space in the structure that communicates with the openings on the surface. (5) A method of preparing a composition containing a component that forms a structure, a component that forms an internal space in the structure that communicates with the openings on the surface, and the detecting agent, forming an internal space in the structure that communicates with the openings on the surface and retaining the detecting agent in the internal space, and then fixing the composition on a base layer. In the present invention, from the viewpoints of ease of production of the laminate and prevention of impurities from being mixed into the laminate, methods (1) to (3) are preferred, method (1) or (2) is more preferred, and method (1) is even more preferred.

[0043] In addition, when mixing, dissolving or dispersing the components in forming the color-changing layer forming material, etc., a stirrer can be used as necessary. At this time, it is preferable to prevent contaminating components caused by the stirrer from being mixed. When mixing, dissolving or dispersing, for example, a method of putting the detecting agent into the solvent, a method of putting the solvent into the detecting agent, a method of putting each component constituting the detecting agent into the solvent in order, etc. can be used. When the sensing agent is retained within the internal space, the solvent can be removed by drying or other means, if necessary. When providing a structure on a base layer, the base layer may be subjected to a surface treatment as necessary to improve adhesion. Examples of the surface treatment include at least one selected from the group consisting of well-known methods such as primer treatment, chemical conversion treatment, plasma treatment, corona treatment, flame treatment, and sandblasting treatment.

[0044] <Applications of laminates> The laminate of the present invention can be used not only to detect plasma or the like but also as an indicator for detecting the uniformity of treatment by plasma or the like by measuring the color difference based on the color of the discoloration layer before treatment. For example, the laminate can be used as an indicator for use in an apparatus for manufacturing electronic devices such as semiconductors, LEDs, semiconductor lasers, power devices, solar cells, liquid crystal displays, organic EL displays, and MEMS. It can also be used as a general-purpose, simplified indicator for detecting plasma, etc. Furthermore, as described below, it can also be used as a temperature indicator.

[0045] When using the indicator, the indicator of the present invention may be placed at a location where a substrate is placed in each electronic device manufacturing apparatus where the above-mentioned processes are carried out during the manufacture of electronic devices. For example, the wafer may be placed horizontally (horizontally) on a wafer stage, heater, vacuum chuck table, etc., or may be placed vertically (vertically) using a wafer boat, etc. When the indicator of the present invention has the same shape as a substrate used in manufacturing an electronic device, it can be handled and installed in the same manner as a substrate. In such a case, an indicator placed within the apparatus changes color when exposed to the treatment, and the in-plane uniformity of the treatment can be easily detected.

[0046] [Temperature indicator] The inventors have found that the laminate of the present invention has a temperature-dependent characteristic in which the higher the temperature, the greater the discoloration. As a result, when the surface temperature of the workpiece (wafer, etc.) varies (is non-uniform) during treatment with plasma or the like, particularly during plasma treatment, a discoloration distribution occurs in the laminate. It has been found that by reading this discoloration distribution, it is possible to easily and relatively detect the temperature distribution on the surface of the workpiece. Specifically, by utilizing the temperature-dependent characteristics of a laminate, in which the color change sensitivity increases with temperature, and measuring the color difference between different color change areas, it becomes possible to indirectly measure the temperature difference within the plane. For example, the inventors have calculated the temperature difference in the plane of the laminate X1 of the embodiment as a function of the plasma treatment time and ΔE * From this, for example, when plasma treatment is performed for 15 minutes, ΔE * It can be estimated that in the area where a discoloration distribution with ab of about 8 occurred, a temperature difference of 80 to 100°C occurred during plasma treatment.

[0047] The temperature indicator of the present invention is particularly useful for detecting temperature distribution in a plasma-based etching process in a semiconductor manufacturing process, which is greatly affected by temperature. In particular, by forming the temperature indicator of the present invention from a laminate with a low metal content, it is possible to easily perform partial temperature measurement without causing contamination inside the device. Furthermore, compared to measurement systems in which a thermocouple is attached to a wafer substrate or measurement systems that use a temperature indicator that changes color depending on the temperature, the temperature indicator of the present invention is extremely useful in that it does not cause localized temperature increases due to electric field concentration caused by unevenness during plasma processing, and there is no concern about metal contamination scattering. EXAMPLES

[0048] The laminate and indicator of the present invention will be described in more detail below with reference to examples and comparative examples. However, the present invention is not limited to these examples. In addition, unless otherwise specified, "%" means "% by mass" and "parts" means "parts by mass".

[0049] [Preparation of Laminate] A polyimide precursor solution, an amide solvent (a good solvent for polyimide), an ether solvent (a poor solvent for polyimide), and a perylene-based red dye (a detection agent) were mixed and stirred to obtain a color-change layer-forming material. The obtained color-change layer-forming material was applied to a silicon substrate, dried and heat-treated to form a porous color-change layer on the silicon substrate, thereby preparing laminates X1 to X9. Table 1 shows the film density, film thickness and concentration of the detecting agent (perylene-based red dye) in the color-change layer of each of the laminates X1 to X9.

[0050] [Discoloration due to plasma] The discoloration layers of the laminates X1 to X9 were subjected to plasma treatment under the following conditions. L of discolored layer after a specified plasma treatment time * , a * and b * was measured with a colorimeter, and the color difference ΔE before and after plasma treatment for each plasma treatment time was * The results are shown in Table 1. <Plasma treatment conditions> Source gas: CF4:O2=1:1 mixed gas Plasma device: Capacitively Coupled Plasma (Parallel Plate CCP) type plasma device Gas flow rate: CF4:O2=75:75sccm Initial pressure: 5×10 -4 Pa or less Processing pressure: 20Pa Interelectrode distance: 40mm Power: 50W Power supply: 13.56MHz

[0051] [Table 1]

[0052] From Table 1, the film density of the discoloration layer is 0.20 to 1.00 g / cm 3 In particular, when the film density of the color-change layer is 0.30 g / cm3, a laminate having a good color-change property (color-change sensitivity) to plasma can be obtained. 3 More than 0.50g / cm 3 Less than 0.44 g / cm 3 If it is within the range below, the color difference ΔE before and after irradiation can be reduced even with a short period of irradiation. * It can be seen that a laminate with high discoloration sensitivity is obtained with a large ab. The density of the polyimide used is 1.42 g / cm 3 It is. It was also found that the color change sensitivity can be adjusted by reducing the film thickness of the color change layer and the concentration of the detecting agent, in addition to the film density of the color change layer. In particular, when the film thickness of the color change layer is less than 10 μm, preferably in the range of 9.5 μm to 4.0 μm, the color change sensitivity can be increased.

[0053] [Color change due to temperature] Using the laminate X1, the temperature of the stage on which the silicon wafer is placed is set to 20°C, 100°C, or 200°C, and plasma treatment is performed under the following conditions. The plasma treatment time (min) and color difference ΔE, which indicates the discoloration sensitivity, at each temperature are measured. * The relationship between a and b was calculated, and the results are shown in Figure 1. <Plasma treatment conditions> Source gas: CF4:O2=1:1 mixed gas Plasma equipment: Inductively Coupled Plasma (ICP) type plasma equipment Gas flow rate: CF4:O2=20:20sccm Initial pressure: 5×10 -4 Pa or less Processing pressure: 10Pa Interelectrode distance: 80mm Power: 75W (top discharge)

[0054] From FIG. 1, it can be seen that the laminate X1 has a temperature dependency in which the color change increases as the temperature increases. By utilizing this characteristic, the presence or absence of wafer temperature variation (unevenness; temperature distribution) during plasma processing and its degree can be detected by ΔE * Reading ab allows easy and relative detection. For example, when a temperature difference of about 80 to 100°C occurs during 15 minutes of plasma treatment, ΔE * It can be seen that a color change occurs with ab of about 8. From this, ΔE * When measuring ab, where a discoloration distribution of about 8 occurs, it is possible to easily indirectly measure that a temperature difference of about 80 to 100°C occurred during plasma processing.

Claims

1. The present invention provides a color-changing layer having a film density of 0.20 g / cm 3 or more and 0.50 g / cm 3 or less, and a base layer, The thickness of the color-changing layer is 0.5 μm or more and 9.5 μm or less, the color-changing layer has a structure having an internal space communicating with the openings on the surface, The internal space contains a detection agent including at least one dye that changes color upon detecting at least one type of ion selected from the group consisting of plasma, ozone, ions, ultraviolet light, and radical-containing gas. Laminate.

2. The film density of the color-changing layer is 0.30 to 0.50 g / cm ３ The laminate according to claim 1 ,

3. The color-changing layer of the laminate was ４ :O ２ Color difference ΔE when treated for 5 minutes with plasma using a gas with a ratio of 1:1 ＊ The laminate according to claim 1 or 2, wherein ab is 10 or more.

4. The laminate according to any one of claims 1 to 3, which has a concealing layer between the color-changing layer and the substrate layer.

5. A temperature indicator used for detecting a temperature distribution occurring during plasma irradiation, comprising the laminate according to any one of claims 1 to 4.

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