Method for manufacturing glass laminate and glass laminate

Abstract

This method for manufacturing a glass laminate comprises forming a film containing a high-refractive-index material on a glass substrate and forming a metasurface structure from the film. The glass substrate has a total alkali metal element content of 200 ppm or less on a mass basis, and the average CTE difference between the glass substrate and the high-refractive-index material before crystallization at 50-200°C is within ±0.5 ppm / K.

Description

Glass laminate manufacturing method and glass laminate

[0001] The present disclosure relates to a method for manufacturing a glass laminate and a glass laminate.

[0002] In conventional semiconductor assembly processes, a silicon substrate and a glass substrate in wafer form are cut and bonded together, and then assembly is performed by die bonding, wire bonding, molding, etc. In recent years, wafer-level packaging technology, in which a silicon substrate and a glass substrate are bonded together in full-size wafer form, an assembly process is performed, and then cutting is performed, has been attracting attention as a next-generation chip-size package (CSP) technology.

[0003] A heat treatment process is required to bond a silicon substrate and a glass substrate. However, the heat treatment process generates a large residual strain in the substrate. Therefore, in Patent Document 1, the elongation rate α １ and the thermal expansion rate α of the silicon bonded to the glass. ２ Ratio α １ / α ２ In addition, Patent Document 2 discloses a glass substrate having a specific average thermal expansion coefficient.

[0004] Japanese Patent Application Laid-Open No. 7-247134 International Publication No. 2016 / 125787

[0005] One embodiment of the glass laminate has a sub-nano-order three-dimensional structure called a meta-atom, which is about one-tenth the wavelength of light, in an arbitrary pattern on a flat transparent glass substrate. In one embodiment of the glass laminate, the meta-atom changes the phase and amplitude of light of a specific wavelength, thereby exhibiting functions such as absorption, reflection, and diffraction. The meta-atom is produced by attaching meta-atom raw materials to a glass substrate, annealing it by heat treatment to form a film, and then processing the film.

[0006] Examples of glass substrates used in glass laminates include quartz glass substrates and alkali-free glass substrates. However, quartz glass substrates have poor machinability and a large difference in thermal expansion coefficient from meta-atom raw materials such as silicon, which causes a problem of substrate warping during the heat treatment process in the production of glass laminates. On the other hand, alkali-free glass substrates, although alkali-free, contain trace amounts of alkali metal elements. Therefore, when producing glass laminates using existing semiconductor manufacturing equipment, there is a concern about process contamination (i.e., contamination of existing semiconductor device manufacturing lines) due to contamination such as metal ions released from the alkali-free glass substrates.

[0007] The present disclosure has been made in view of the above, and relates to providing a method for manufacturing a glass laminate and a glass laminate in which warping of a glass substrate and a film formed on the glass substrate is suppressed and process contamination due to alkali metal ions released from the glass substrate is reduced.

[0008] The present disclosure includes the following aspects. <1> A method for producing a glass laminate, comprising forming a film containing a high refractive index material on a glass substrate and forming a metasurface structure from the film, wherein the glass substrate has a total amount of alkali metal elements of 200 ppm or less by mass, and the difference in average linear expansion coefficient between the glass substrate and the high refractive index material before crystallization at 50 to 200°C is within ±0.5 ppm / K. <2> The method for producing a glass laminate according to <1>, wherein the glass substrate is an alkali-free glass substrate. <3> The method for producing a glass laminate according to <1> or <2>, wherein the difference in average linear expansion coefficient between the glass substrate and the high refractive index material before crystallization is within ±0.3 ppm / K. <4> The method for producing a glass laminate according to any one of <1> to <3>, wherein the content of each of Ti, Cu, Cr, Ce, Ni, and Zn contained in the glass substrate is 20 ppm or less by mass. <5> The method for producing a glass laminate according to any one of <1> to <4>, wherein the content of Fe contained in the glass substrate is 100 ppm or less by mass. <6> The area of ​​the main surface of the glass substrate is 0.015 m ２<7> The method for producing a glass laminate according to any one of <1> to <5>, wherein the main surface of the glass substrate has an area of ​​0.025 m ２ The method for producing a glass laminate according to any one of <1> to <5>, wherein the thickness of the glass substrate is 0.5 to 3.0 mm. <8> The method for producing a glass laminate according to any one of <1> to <7>, wherein the thickness of the glass substrate is 0.5 to 3.0 mm. <9> The method for producing a glass laminate according to any one of <1> to <8>, wherein the thickness of the film containing a high refractive index material is 0.00001 to 0.01 times the thickness of the glass substrate. <10> The method for producing a glass laminate according to any one of <1> to <9>, wherein the thickness deviation of the glass substrate is 5 μm or less and the surface roughness of the glass substrate is 5 nm or less. <11> The method for producing a glass laminate according to any one of <1> to <10>, wherein the thickness deviation of the glass substrate is 3 μm or less and the surface roughness of the glass substrate is 3 nm or less. <12> The method for producing a glass laminate according to any one of <1> to <11>, wherein the warpage of the glass substrate on which the film is formed is 50 μm or less, as measured in accordance with JIS B 0621. <13> The method for producing a glass laminate according to any one of <1> to <12>, wherein the amount of warpage of the glass substrate on which the film is formed is 30 μm or less, as measured in accordance with JIS B 0621. <14> The method for producing a glass laminate according to any one of <1> to <13>, wherein the high refractive index material is silicon or an oxide thereof, gallium or an oxide thereof, germanium or an oxide thereof, indium or an oxide thereof, titanium dioxide, sapphire, niobium pentoxide, silicon nitride, or gallium nitride. <15> The method for producing a glass laminate according to any one of <1> to <14>, comprising forming a metasurface structure on the glass substrate by subjecting the film to photolithography, electron beam lithography, or nanoimprint lithography. <16> The method for producing a glass laminate according to any one of <1> to <15>, wherein the surface roughness of the end face of the glass substrate is 50 nm or less. <17> The density of the glass substrate is 2.20 g / cm ３ 2.60g / cm or more ３<18> The method for producing a glass laminate according to any one of <1> to <17>, wherein the thickness of the film containing the high refractive index material is 1 μm or less. <19> A glass laminate comprising a glass substrate and a metasurface structure containing a high refractive index material, wherein the glass substrate has a total amount of alkali metal elements of 200 ppm or less by mass, and wherein a difference in average linear expansion coefficient between the glass substrate and the high refractive index material before crystallization at 50 to 200° C. is within ±0.5 ppm / K.

[0009] According to the present disclosure, there are provided a method for manufacturing a glass laminate and a glass laminate in which warping of a glass substrate and a film formed on the glass substrate is suppressed and process contamination due to alkali metal ions released from the glass substrate is reduced.

[0010] An embodiment of the present disclosure will be described in detail below. However, the present disclosure is not limited to the following embodiment. In the following disclosure, components (including element steps, etc.) are not essential unless otherwise specified. The same applies to numerical values ​​and their ranges, and do not limit the present disclosure.

[0011] In the present disclosure, the term "step" includes not only a step that is independent of other steps, but also a step that cannot be clearly distinguished from other steps as long as the purpose of that step is achieved. In the present disclosure, numerical ranges indicated using "to" include the numerical values ​​before and after "to" as the lower and upper limits, respectively. In numerical ranges described in stages in the present disclosure, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another staged numerical range. Furthermore, in numerical ranges described in the present disclosure, the upper or lower limit of that numerical range may be replaced with a value shown in the examples. In the present disclosure, when multiple substances corresponding to each component are present in the composition, the content of each component in the composition means the total content of those multiple substances present in the composition, unless otherwise specified. In the present disclosure, when multiple elements are listed using "or," this does not exclude the selection of multiple elements in combination unless otherwise specified, unless technically inconsistent. In the present disclosure, when elements are described in the singular, this does not exclude the presence of multiple elements unless technically inconsistent, unless otherwise specified. In the present disclosure, multiple exemplary aspects described separately may be combined with each other to form a new aspect, unless they contradict each other.

[0012] <<Method for manufacturing a glass laminate>> The method for manufacturing a glass laminate disclosed herein includes forming a film containing a high refractive index material on a glass substrate, and forming a metasurface structure from the film, wherein the glass substrate has a total amount of alkali metal elements of 200 ppm or less by mass, and the difference in average linear expansion coefficient (also referred to as average CTE) between the glass substrate and the high refractive index material before crystallization at 50 to 200°C is within ±0.5 ppm / K.

[0013] According to the method for manufacturing a glass laminate of the present disclosure, warping of a glass substrate and a film formed on the glass substrate is suppressed, and process contamination due to alkali metal ions released from the glass substrate is reduced.

[0014] Conventional alkali-free glass substrates contain a total of 10% alkali metal elements. ２The concentrations were on the order of ppm or more. Since it is desirable to avoid contamination of semiconductors with metal ions and the like, alkali-free glass containing trace amounts of alkali metal elements is not typically used as the glass substrate for semiconductors, but quartz glass is instead. Even when semiconductor manufacturing equipment is diverted to manufacturing glass laminates, the use of alkali-free glass, which may cause contamination, is usually avoided. However, in the present disclosure, as described above, the total amount of alkali metal elements in the glass substrate is kept to 200 ppm or less by mass, so that process contamination by alkali metal ions does not pose a problem even when existing semiconductor manufacturing equipment is diverted to manufacturing glass laminates.

[0015] Furthermore, in the method for manufacturing a glass laminate according to the present disclosure, the difference in average CTE between the glass substrate and the high refractive index material before crystallization is within ±0.5 ppm / K at 50 to 200° C. When the difference in average CTE between the glass substrate and the high refractive index material before crystallization is within ±0.5 ppm / K, warping of the glass substrate and the film containing the crystallized high refractive index material can be significantly suppressed during a heat treatment step, such as for crystallizing the high refractive index material.

[0016] Therefore, according to the method for producing a glass laminate of the present disclosure, warping of the glass substrate and the film formed on the glass substrate is suppressed, which facilitates handling in the production process and mass production. Furthermore, according to the method for producing a glass laminate of the present disclosure, process contamination due to alkali metal ions released from the glass substrate is reduced, which enables the glass laminate to be produced using existing semiconductor production equipment.

[0017] <Glass Substrate> (Metal Elements) The glass substrate used in the method for producing a glass laminate of the present disclosure is preferably an alkali-free glass substrate, and the total amount of alkali metal elements is 200 ppm or less by mass. From the viewpoint of reducing contamination of semiconductor manufacturing equipment, the total amount of alkali metal elements in the glass substrate is preferably 100 ppm or less by mass, more preferably 80 ppm or less, and even more preferably 50 ppm or less. The lower limit of the total amount of alkali metal elements in the glass substrate is not particularly limited, and may be 0 ppm or more or more than 0 ppm. The total amount of alkali metal elements in the glass substrate may be 0 to 200 ppm by mass. In the present disclosure, the total amount of alkali metal elements in the glass substrate is calculated by analyzing the content of each alkali metal, such as Na and K, based on an ICP-MS method and calculating the total amount of the analysis results.

[0018] From the viewpoint of reducing contamination of semiconductor manufacturing equipment, the content of each of Ti, Cu, Cr, Ce, Ni, and Zn contained in the glass substrate is preferably 20 ppm or less by mass, more preferably 10 ppm or less, and even more preferably 5 ppm or less. The lower limit of the content of each of Ti, Cu, Cr, Ce, Ni, and Zn contained in the glass substrate is not particularly limited, and each may be 0 ppm or more or more than 0 ppm. The content of each of Ti, Cu, Cr, Ce, Ni, and Zn contained in the glass substrate may be 0 to 20 ppm by mass. In the present disclosure, the content of each of Ti, Cu, Cr, Ce, Ni, and Zn contained in the glass substrate can be measured based on an ICP-MS method.

[0019] From the viewpoint of reducing contamination of semiconductor manufacturing equipment, the total amount of Fe contained in the glass substrate is preferably 100 ppm or less by mass, and more preferably 50 ppm or less. The lower limit of the total amount of Fe contained in the glass substrate is not particularly limited, and may be 0 ppm or more or more than 0 ppm. The total amount of Fe contained in the glass substrate may be 0 to 100 ppm by mass. In the present disclosure, the total amount of Fe contained in the glass substrate can be measured based on an ICP-MS method.

[0020] There are no particular limitations on the method for reducing the total amount of alkali metal elements, the contents of Ti, Cu, Cr, Ce, Ni, and Zn, and the total amount of Fe contained in the glass substrate. Examples of such methods include manufacturing a glass substrate using raw materials with higher purity than conventional ones, manufacturing a glass substrate in equipment separated from equipment for manufacturing other products other than the glass substrate of the present disclosure, and manufacturing a glass substrate by controlling the cooling process of the glass substrate (for example, by controlling the material of the cooling device, the cooling medium, and preventing contamination from the surrounding atmosphere during cooling), and these methods may be combined.

[0021] (Composition) The composition of the glass substrate is not particularly limited as long as the total amount of alkali metal elements is 200 ppm or less by mass. ２ , Al ２ O ３ , B ２ O ３ , MgO, CaO, SrO, and BaO.

[0022] The composition of the glass substrate is expressed in mole percentage based on oxides: SiO ２ :50~75%, Al ２ O ３ : 6-16%, B ２ O ３ : 0 to 15%, MgO: 0 to 15%, CaO: 0 to 13%, SrO: 0 to 11%, and BaO: 0 to 9.5%.

[0023] SiO ２ is a component that forms the skeleton of glass. ２ When the content of SiO is 50% or more, the heat resistance, chemical durability, and weather resistance are good. ２ When the content of SiO is 75% or less, the viscosity of the glass when melted does not become too high and the meltability is good. ２ The content of SiO is preferably 60% or more, and more preferably 64% or more. ２ The content is preferably 70% or less, more preferably 68% or less.

[0024] Al２ O ３ When the content of Al is 6% or more, the weather resistance, heat resistance, and chemical durability are improved, and the Young's modulus is increased. ２ O ３ When the content of Al is 16% or less, the viscosity during glass melting does not become too high, resulting in good meltability and less devitrification. ２ O ３ The content of Al is preferably 8% or more, and more preferably 11% or more. ２ O ３ The content is preferably 14% or less.

[0025] B ２ O ３ Although not an essential component, when contained, the viscosity of the glass during melting does not become too high, resulting in good meltability and less devitrification. ２ O ３ If the content of B is 15% or less, the glass transition temperature becomes high and the Young's modulus becomes high. ２ O ３ The content of B is more preferably 3% or more. ２ O ３ The content is preferably 12% or less, more preferably 6% or less.

[0026] Although MgO is not an essential component, its inclusion improves meltability without excessively increasing the viscosity during glass melting, improving weather resistance and increasing Young's modulus. If the MgO content is 15% or less, the glass is less likely to devitrify. The MgO content is preferably 4% or more, more preferably 6% or more. The MgO content is preferably 10% or less, more preferably 9.5% or less, and even more preferably 9% or less.

[0027] Although CaO is not an essential component, its inclusion improves the melting property and weather resistance without excessively increasing the viscosity during glass melting. If the CaO content is 13% or less, the glass is less likely to devitrify. The CaO content is preferably 4% or more. The CaO content is preferably 10% or less, more preferably 8% or less.

[0028] Although SrO is not an essential component, its inclusion improves the melting property and weather resistance without excessively increasing the viscosity during glass melting. If the SrO content is 11% or less, the glass is less susceptible to devitrification. The SrO content is preferably 0.5% or more. The SrO content is preferably 8% or less, more preferably 3% or less.

[0029] Although BaO is not an essential component, its inclusion improves the melting property and weather resistance without excessively increasing the viscosity during glass melting. If the BaO content is 9.5% or less, the glass is less likely to devitrify. The BaO content is preferably 3% or less, and more preferably 2% or less.

[0030] Alternatively, the composition of the glass substrate is, in terms of mass percentage based on oxides, SiO ２ :40~57%, Al ２ O ３ : 2.0 to 12%, CaO: 1 to 16%, SrO: 8 to 21.5%, BaO: 14 to 31.5%, MgO: 0 to 3%, and B ２ O ３ : 0 to 4% is also acceptable.

[0031] The glass substrate may contain, as a fining agent, for example, SnO ２ , S.O. ３ , Cl, F, etc. may be contained.

[0032] The glass substrate may be coated with, for example, ZnO, Li, in order to improve weather resistance, solubility, devitrification resistance, ultraviolet shielding, infrared shielding, ultraviolet transmission, or infrared transmission. ２ O.W.O. ３ , Nb ２ O ５ , V ２ O ５ , Bi ２ O ３ , MoO ３ , P ２ O ５ , Ga ２ O ３ , I ２ O ５ , In ２ O ５ , or Ge ２ O ５ etc. may be contained.

[0033] The glass substrate is made of ZrO ２ , Y ２ O ３ , La ２ O ３ , TiO ２ , and SnO ２ The total amount of Y may be 2% or less, preferably 1% or less, and more preferably 0.5% or less, expressed as mole percentage based on oxides. ２ O ３ , La ２ O ３ and TiO ２ This also contributes to improving the Young's modulus of the glass substrate.

[0034] Considering the environmental impact of glass substrates, ２ O ３ and Sb ２ O ３ It is preferable that the composition is substantially free of ZnO. In consideration of stable float molding, it is also preferable that the composition is substantially free of ZnO. In the present disclosure, "substantially free of a specific substance" means that the composition is completely free of the specific substance, or that the composition may contain the specific substance as an impurity that is inevitably mixed in during production.

[0035] (Average Coefficient of Linear Expansion (Average CTE)) In the glass substrate used in the method for producing a glass laminate according to the present disclosure, the difference in average CTE between the glass substrate and a high refractive index material (described later) before crystallization at 50 to 200°C is within ±0.5 ppm / K. From the viewpoint of suppressing warping of the glass substrate and warping of a film containing a high refractive index material, the difference in average CTE between the glass substrate and a high refractive index material before crystallization at 50 to 200°C is preferably within ±0.3 ppm / K, more preferably within ±0.2 ppm / K, and even more preferably within ±0.1 ppm / K. The optimal value depends on the application of the glass laminate; for example, in the case of a CMOS device process, the difference in average CTE between the glass substrate and the high refractive index material before crystallization is preferably within ±0.02 ppm / K. Note that a highly uniform film may be formed by crystallizing the high refractive index material before crystallization. In the present disclosure, the average CTE at 50 to 200°C is the average CTE measured by the method specified in JIS R3102 (1995) in a temperature range of 50 to 200°C for measuring the coefficient of linear expansion (CTE). Therefore, for example, the difference in average CTE between the glass substrate and the high refractive index material before crystallization at 50 to 200°C can be determined from the difference between the average CTE of the glass substrate at 50 to 200°C and the average CTE of the high refractive index material before crystallization at 50 to 200°C.

[0036] Furthermore, if the interfacial adhesion between the glass substrate and the high refractive index material is weak, cracks and wrinkles will occur on the film side containing the high refractive index material. By keeping the difference in average CTE between the glass substrate and the high refractive index material before crystallization within ±0.5 ppm / K at 50 to 200°C, even if the interfacial adhesion between the glass substrate and the high refractive index material is weak, the occurrence of film cracks and wrinkles caused by the difference in CTE between the glass and the high refractive index material can be suppressed.

[0037] Average CTEα of glass substrate between 50 and 100°C ５０／１００ and the average CTEα of the high refractive index material at 50 to 100°C before crystallization Ｈｒ５０／１００ The difference between (= α ５０／１００ -α Ｈｒ５０／１００) is preferably within ±0.25 ppm / °C, more preferably within ±0.15 ppm / °C, even more preferably within ±0.10 ppm / °C, particularly preferably within ±0.05 ppm / °C, and most preferably within ±0.03 ppm / °C. When the high refractive index material is silicon, the preferred numerical range is the same as the preferred numerical range for the high refractive index material.

[0038] Average CTEα of glass substrate between 100 and 200°C １００／２００ and the average CTEα of the high refractive index material at 100 to 200°C before crystallization Ｈｒ１００／２００ The difference between (= α １００／２００ -α Ｈｒ１００／２００ ) is preferably within ±0.25 ppm / °C, more preferably within ±0.15 ppm / °C, even more preferably within ±0.10 ppm / °C, particularly preferably within ±0.05 ppm / °C, and most preferably within ±0.03 ppm / °C.

[0039] Average CTEα of glass substrate between 200 and 300°C ２００／３００ and the average CTEα of the high refractive index material at 200 to 300°C before crystallization Ｈｒ２００／３００ The difference between (= α ２００／３００ -α Ｈｒ２００／３００ ) is preferably within ±0.25 ppm / °C, more preferably within ±0.15 ppm / °C, even more preferably within ±0.10 ppm / °C, particularly preferably within ±0.05 ppm / °C, and most preferably within ±0.03 ppm / °C.

[0040] [α ２００／３００ -α Ｈｒ２００／３００ ] and [α ５０／１００ -α Ｈｒ５０／１００ The difference between the temperature and the temperature is preferably within ±0.16 ppm / °C, more preferably within ±0.12 ppm / °C, and even more preferably within ±0.08 ppm / °C.

[0041] In the method for producing a glass laminate according to the present disclosure, it is important to reduce the difference in average CTE between the glass substrate and the high refractive index material before crystallization in order to suppress warpage of the glass substrate and the film containing the high refractive index material, and the magnitude of the average CTE value itself is not particularly limited. That is, the average CTE of the glass substrate is not particularly limited, and for example, the average CTE α at 50 to 100°C is ５０／１００is 2.70 to 3.20 ppm / °C, and the average CTEα at 200 to 300°C ２００／３００ is 3.45 to 3.95 ppm / °C, and the average CTEα ２００／３００ The average CTEα between 50 and 100°C ５０／１００ The value α divided by ２００／３００ / α ５０／１００ In the case where the high refractive index material is silicon, the average CTE value of the glass substrate is particularly preferable. Ｘ／Ｙ is the average CTE measured in the temperature range of X to Y°C, as determined by the method specified in JIS R3102 (1995).

[0042] The glass substrate has an average CTE of α at 50 to 100°C. ５０／１００ However, it may be 2.70 to 3.20 ppm / °C. ５０／１００ is preferably 2.80 ppm / °C or more, more preferably 2.90 ppm / °C or more, even more preferably 2.91 ppm / °C or more, and particularly preferably 2.92 ppm / °C or more. ５０／１００ is preferably 3.10 ppm / °C or less, more preferably 3.00 ppm / °C or less, even more preferably 2.96 ppm / °C or less, and particularly preferably 2.94 ppm / °C or less. ５０／１００ When is in the above range, the difference in average CTE from the high refractive index material (particularly silicon) before crystallization is smaller, and therefore, the warpage of the glass substrate and the warpage of the film containing the high refractive index material can be reduced in the heat treatment step of annealing the high refractive index material attached to the glass substrate while ensuring the process margin.

[0043] The glass substrate has an average CTE of α at 100 to 200°C. １００／２００ is preferably 3.13 to 3.63 ppm / °C, more preferably 3.23 to 3.53 ppm / °C. １００／２００ When α is in the above range, the difference in average CTE from the high refractive index material (particularly silicon) before crystallization is smaller, and therefore, warpage of the glass substrate and warpage of the film containing the high refractive index material can be reduced in the heat treatment step of annealing the high refractive index material attached to the glass substrate while ensuring the process margin. １００／２００is more preferably 3.33 ppm / °C or more, particularly preferably 3.34 ppm / °C or more, and most preferably 3.35 ppm / °C or more. １００／２００ is more preferably 3.43 ppm / °C or less, particularly preferably 3.41 ppm / °C or less, and most preferably 3.38 ppm / °C or less.

[0044] The glass substrate has an average CTE of α at 200-300°C. ２００／３００ may be 3.45 to 3.95 ppm / °C. ２００／３００ is preferably 3.55 ppm / °C or more, more preferably 3.65 ppm / °C or more, particularly preferably 3.66 ppm / °C or more, and most preferably 3.68 ppm / °C or more. ２００／３００ is preferably 3.85 ppm / °C or less, more preferably 3.75 ppm / °C or less, particularly preferably 3.73 ppm / °C or less, and most preferably 3.71 ppm / °C or less. ２００／３００ When α is in the above range, the difference in average CTE from the high refractive index material (particularly silicon) before crystallization is smaller, and therefore, warpage of the glass substrate and warpage of the film containing the high refractive index material can be reduced in the heat treatment step of annealing the high refractive index material attached to the glass substrate while ensuring the process margin. ２００／３００ If the refractive index is 3.55 to 3.85 ppm / ° C., the difference in average CTE from the high refractive index material before crystallization becomes sufficiently small, so that defects caused by the difference in average CTE can be further suppressed.

[0045] The glass substrate has an average CTE of α at 200-300°C. ２００／３００ Average CTEα at 50 to 100 ° C ５０／１００ The value α divided by ２００／３００ / α ５０／１００ may be 1.20 to 1.30. ２００／３００ / α ５０／１００ When α is 1.20 to 1.30, the difference in average CTE from the high refractive index material (particularly silicon) before crystallization is smaller, and therefore warping of the glass substrate and the film containing the high refractive index material is smaller in the heat treatment step of annealing the high refractive index material attached to the glass substrate. ２００／３００ / α ５０／１００ is preferably 1.24 to 1.27.

[0046] (Size) The glass laminate, which is currently in the development phase, is manufactured in small piece sizes, and warping of the glass substrate and the film containing the high refractive index material due to the heat treatment process is minimal. However, when mass-producing glass laminates at substrate sizes common in semiconductor processes, the influence of warping, which was not apparent in the previous small piece sizes, becomes more pronounced as the glass laminate becomes larger. The area of ​​the main surface of the glass substrate is 0.015 m ２ The area is preferably 0.015 m or more. ２ If the area is 0.025 m, a large number of glass laminate pieces can be manufactured from a single glass substrate. Furthermore, the warpage suppression effect of the manufacturing method of the present disclosure is also increased. ２ More preferably, 0.04 m or more ２ More preferably, 0.05 m or more ２ The above is particularly preferred. The larger the area of ​​the main surface, the more optical components can be obtained from the glass laminate, improving mass productivity and reducing variations in the quality of the optical components, which is preferable. There is no particular upper limit to the area of ​​the main surface of the glass substrate, and it is within 1 m ２ The area of ​​the main surface of the glass substrate may be, for example, 0.015 to 1 m ２ That's fine too.

[0047] In the present disclosure, the main surface of the glass substrate refers to the surface of the glass substrate on which a film containing a high refractive index material is formed. The area of ​​the main surface of the glass substrate can be measured by image analysis using a transmission type dimension measuring instrument or the like.

[0048] When glass laminates are mass-produced in sizes that are common substrate sizes in semiconductor processes, such as a diameter of 6 inches (150 mm) for circular substrates or a side length of 6 inches (150 mm) or more for square substrates, the larger size of the glass laminate makes the effects of warping, which were not apparent with previous small piece sizes, more pronounced. When the glass substrate is circular, the diameter of the glass substrate is preferably 6 inches (150 mm) or more, more preferably 8 inches (200 mm) or more, and even more preferably 12 inches (300 mm) or more. The upper limit of the diameter of the glass substrate is not particularly limited, and may be 50 inches (1270 mm) or less. The diameter of the glass substrate may be, for example, 6 to 50 inches. When the glass substrate is square, the length of one side of the glass substrate is preferably 6 inches (150 mm) or more, more preferably 8 inches (200 mm) or more, and even more preferably 12 inches (300 mm) or more. The upper limit of the length of one side of the glass substrate is not particularly limited, and may be 50 inches (1270 mm) or less. The length of one side of the glass substrate may be, for example, 6 to 50 inches.

[0049] (Thickness) The thickness of the glass substrate is not particularly limited, and is preferably 3.0 mm or less, more preferably 2.0 mm or less, and even more preferably 1.0 mm or less, from the viewpoint of utilizing existing semiconductor manufacturing equipment for the production of the glass laminate, the efficiency of the back-grinding process, and the need for optical properties as a glass laminate. The lower limit of the thickness of the glass substrate is not particularly limited, and is preferably 0.5 mm or more in consideration of process transportability. The thickness of the glass substrate may be, for example, 0.5 to 3.0 mm. Furthermore, when a thinner laminate is desired, a so-called back-grinding process can be introduced in the production process of the glass laminate, in which only the glass substrate side of the glass laminate (i.e., the surface opposite to the surface on which the film containing the high refractive index material is formed) is further thinned by grinding and polishing, etc. In this case, the thickness of the glass substrate becomes even thinner than 0.5 mm. Since the susceptibility to warping also varies depending on the thickness of the film containing a high refractive index material, the thickness of the film containing a high refractive index material is preferably 0.00001 to 0.01 times the thickness of the glass substrate, more preferably 0.00001 to 0.005 times, even more preferably 0.0001 to 0.0035 times, and may be 0.0001 to 0.001 times. In the present disclosure, the thickness of the glass substrate is measured by an optical interference thickness measurement method. The optical interference thickness measurement method involves measuring the phase difference of reflected light from the front and back surfaces using, for example, an optical interference thickness measurement device (FlatMaster 200) from Corning-Tropel.

[0050] (Thickness Deviation (TTV)) From the viewpoint of processing the crystallized high refractive index material with high precision, the thickness deviation (TTV) of the glass substrate is preferably 5 μm or less, more preferably 3 μm or less, and even more preferably 1 μm or less. When the thickness deviation of the glass substrate is 1 μm or less, the film thickness uniformity of the high refractive index material within the plane of the glass laminate is improved, the variation in optical property quality can be reduced, and this leads to improved productivity of optical components obtained from the glass laminate. The lower limit of the thickness deviation of the glass substrate is not particularly limited and may be 0 μm or more. The thickness deviation of the glass substrate may be, for example, 0 to 5 μm. In the present disclosure, the thickness deviation of the glass substrate is measured by optical interferometry.

[0051] From the viewpoint of processing crystallized high refractive index materials with high precision, the warp of the glass substrate (the difference between the maximum and minimum deviations of the central surface from a reference surface) is preferably 50 μm or less, more preferably 30 μm or less, and even more preferably 20 μm or less. By setting the warp of the glass substrate within this range, the transportability in the flow process is improved, and the processability during film formation and microfabrication of the high refractive index material is also improved. The lower limit of the warp of the glass substrate is not particularly limited, and may be 0 μm or more. The warp of the glass substrate may be, for example, 0 to 50 μm. In the present disclosure, the warp of the glass substrate is measured by optical interferometry.

[0052] (Amount of Warpage) In all processes from the glass substrate to the production of the glass laminate, the amount of warpage of the glass substrate on which a film containing a high refractive index material is formed is preferably 50 μm or less, more preferably 30 μm or less, and even more preferably 20 μm or less. Suppressing the amount of warpage to 50 μm or less reduces the impact of warpage in the manufacturing process in mass production. The lower limit of the amount of warpage of the glass substrate on which a film containing a high refractive index material is formed may be 0 μm or more. The amount of warpage of the glass substrate may be, for example, 0 to 50 μm. In the present disclosure, the amount of warpage of the glass substrate is defined as the flatness measured according to JIS B 0621:1984 (ISO 1101:1983).

[0053] (Surface roughness (Ra)) From the viewpoint of processing a crystallized high refractive index material with high precision, the surface roughness (Ra) of the glass substrate is preferably 5 nm or less, more preferably 3 nm or less, and even more preferably 1 nm or less. Light scattering on the surface of the glass laminate can be reduced, the optical properties are improved, and light loss is also reduced. The lower limit of the surface roughness of the glass substrate is not particularly limited, and may be 0 nm or more. The surface roughness of the glass substrate may be, for example, 0 to 5 nm. In the present disclosure, the surface roughness of the glass substrate is measured by atomic force microscopy (AFM).

[0054] (End Face Surface Roughness) From the viewpoint of preventing debris and dust generation, the end face surface roughness of the glass substrate is preferably 50 nm or less, more preferably 25 nm or less, and even more preferably 10 nm or less. The lower limit of the end face surface roughness of the glass substrate is not particularly limited, and may be 0 nm or more. The end face surface roughness of the glass substrate may be, for example, 0 to 50 nm. In the present disclosure, the end face surface roughness of the glass substrate is measured using a laser microscope.

[0055] (Edge Shape) From the viewpoint of preventing damage due to physical contact of the edge surface during the manufacturing process and packaging, the edge shape of the glass substrate is preferably slightly chamfered, more preferably C-chamfered, and even more preferably R-chamfered.

[0056] (Shape) From the viewpoint of manufacturing a glass laminate with high precision, the shape of the glass substrate is preferably circular. The shape of the glass substrate may be elliptical or rectangular. In order to match with the high refractive index material to be attached and annealed, the glass substrate may have a notch at the edge, and if the glass substrate is circular, part of the periphery of the glass substrate may be straight.

[0057] (Refractive Index) The refractive index of the glass substrate at 589.6 nm is preferably 1.00 to 2.00, more preferably 1.20 to 1.80, and even more preferably 1.40 to 1.60. In the present disclosure, the refractive index can be measured using a precision refractometer in accordance with the V-block method (JIS B 7071-2:2024 (ISO 21395-2:2022)).

[0058] (Other properties) The glass substrate contains (Al) in mole percentage based on oxides. ２ O ３ It is preferable that the content of (Al) is equal to or greater than the content of (MgO). ２ O ３ If (content of)≧(content of MgO), the average CTE of the glass substrate can be easily matched to the average CTE of the high refractive index material before crystallization, and warping of the glass substrate and the film containing the high refractive index material can be reduced in the heat treatment step of annealing the high refractive index material attached to the glass substrate.

[0059] The glass substrate has a devitrification viscosity (ηTL) of 10 ３．８ The devitrification viscosity is preferably 10 d·Pa·s or more.３．８ If the viscosity is d·Pa·s or more, it is easy to form stably. ４．０ d·Pa·s or more is more preferable, and 10 ４．２ The devitrification viscosity is more preferably d·Pa·s or more. The devitrification viscosity is determined from the glass viscosity at the glass devitrification temperature by determining the coefficients of the Fulcher equation from the results of measuring the glass viscosity of the molten glass at a high temperature (1000 to 1600°C) using a rotational viscometer, and then using the Fulcher equation using the coefficients.

[0060] The glass substrate preferably has a Young's modulus of 70 GPa or more. If the Young's modulus is 70 GPa or more, warping or cracking of the glass substrate occurring during the slow cooling process in manufacturing the glass substrate can be more effectively suppressed. In addition, breakage due to contact with high refractive index materials or peripheral members can be more effectively suppressed. The Young's modulus is more preferably 72 GPa or more, even more preferably 75 GPa or more, and particularly preferably 78 GPa or more. The Young's modulus can be measured by an ultrasonic pulse method.

[0061] The Young's modulus is preferably 100 GPa or less. If the Young's modulus is 100 GPa or less, the brittleness of the glass can be reduced, and chipping during cutting and dicing of the glass substrate can be reduced. The Young's modulus is more preferably 90 GPa or less, and even more preferably 87 GPa or less. The Young's modulus may be, for example, 70 to 87 GPa.

[0062] The density of the glass substrate is not particularly limited, and the density is 6.0 g / cm ３ Further, the density is preferably 2.60 g / cm or less. ３ If the density is 2.55 g / cm or less, the glass substrate is lightweight and the deflection of the glass substrate due to its own weight can be reduced. ３ More preferably, 2.50 g / cm or less ３ The following is even more preferred: The density can be measured by Archimedes' method using a glass block of about 20 g containing no bubbles.

[0063] The density is 2.20 g / cm ３ The density is preferably 2.20 g / cm or more. ３ If the density is 2.30 g / cm or more, the Vickers hardness of the glass increases, making the glass surface less susceptible to scratches. ３More preferably, 2.40 g / cm ３ More preferably, 2.45 g / cm ３ The above is particularly preferred.

[0064] The density of defects contained in the glass substrate is 1 / cm ２ The following is preferable. Defects contained in a glass substrate refer to bubbles, scratches, metal foreign matter such as platinum, and unmelted raw materials present on the surface or inside of the glass substrate, and refer to defects having a size of 0.5 μm or more and 1 mm or less. If the defects are larger than 1 mm, they can be easily identified visually, and it is easy to exclude substrates having defects. If the defects are smaller than 0.5 μm, they are sufficiently small that they will not affect the characteristics of the elements even when used as cover glass for CMOS sensors or LCOS.

[0065] In conventional semiconductor assembly processes, the assembly process is performed after cutting the glass substrate, so if there is a defect in the glass substrate, the defective substrate can be removed early in the assembly process. On the other hand, in wafer-level packaging, the glass laminate is singulated at the end of the assembly process, so if there is a defect in the glass substrate, the defective glass substrate can only be removed at the end of the assembly process. As such, in wafer-level packaging, high-quality defect management is required because an increase in the density of defects in the glass substrate results in a significant increase in costs. The defect density is 0.1 / cm. ２ More preferably, 0.01 particles / cm or less ２ The following is even more preferred:

[0066] The glass substrate preferably has a glass transition point (Tg) of 700°C or higher. If the Tg is 700°C or higher, dimensional changes in the glass substrate can be further reduced during the heat treatment process. The Tg is more preferably 720°C or higher, and even more preferably 740°C or higher. The glass transition point can be measured using a thermomechanical analyzer (TMA) according to the method specified in JIS R3103-3 (2001) (ISO 7884-8:1987).

[0067] The glass substrate has a virtual viscosity of 10 １１．０ ~10 １４．１ d·Pa·s is preferable. １１．０ ~10１４．１ In order to obtain a viscosity of d·Pa·s, the cooling rate after molding of the glass substrate is preferably 1 to 1200°C / min. １１．０ ~10 １４．１ If the virtual viscosity of the glass substrate is 10 d·Pa·s, the average CTE of the glass substrate will be close to the average CTE of the high refractive index material before crystallization, and warping of the glass substrate and the film containing the high refractive index material will be smaller during the heat treatment process of annealing the high refractive index material attached to the glass substrate. １２．１ ~10 １３．１ d·Pa·s (corresponding to a cooling rate of 10 to 100° C. / min) is preferred.

[0068] The virtual viscosity (η) of glass can be calculated by the following formula (GW Scherer, Relaxation in Glass and Composites, Wiley, New York (1986), p. 159).

[0069] log １０ η=12.3−log １０ |q|

[0070] Here, η is expressed in units of d Pa s, and q is the assumed cooling rate expressed in units of °C / s. The assumed cooling rate q can be determined from a glass substrate by the following method. A plurality of small glass plate pieces are cut out from a single glass substrate having a thickness of 1 mm or less. For example, small pieces measuring 1 cm square are cut out as the glass plate pieces. Each of the cut-out glass plate pieces is heat-treated and cooled at various cooling rates V, and the physical properties of each glass plate piece are measured. The cooling start temperature is preferably a sufficiently high temperature that is not affected by the cooling rate. Typically, it is preferably about Tg+50 to +150°C.

[0071] The physical property values ​​to be measured are not particularly limited, and preferably include density and physical properties closely related to density (e.g., refractive index). １０ V) and plot the physical property values ​​of the glass plate pieces that have been subjected to each heat treatment on the y-axis to create a calibration curve A. The assumed cooling rate q of the glass substrate can be determined from the created calibration curve A using the physical property values ​​of the glass plate piece that has not been subjected to heat treatment.

[0072] The glass substrate has a viscosity of 10 ２The temperature at which the viscosity becomes d Pa s (T ２ The temperature is preferably 1800°C or lower. ２ The heating temperature is more preferably 1750°C or less, further preferably 1700°C or less, and particularly preferably 1650°C or less.

[0073] The glass substrate has a viscosity of 10 ４ The temperature at which the viscosity becomes d Pa s (T ４ The temperature is preferably 1350°C or lower. ４ is more preferably 1300°C or less, further preferably 1275°C or less, and particularly preferably 1250°C or less. ４ is preferably 1100°C or higher.

[0074] The glass substrate preferably has a glass devitrification temperature of 1325° C. or lower, more preferably 1300° C. or lower, even more preferably 1275° C. or lower, and particularly preferably 1250° C. or lower. The glass devitrification temperature is determined by placing crushed glass particles in a platinum dish, heat treating them for 17 hours in an electric furnace controlled at a constant temperature, and observing them with an optical microscope after the heat treatment to determine the average value of the maximum temperature at which crystals precipitate inside the glass and the minimum temperature at which crystals do not precipitate.

[0075] The glass substrate is 0.0177×(SiO ２ content)−0.0173×(Al ２ O ３ Content of B) + 0.0377 × (B ２ O ３ (content of MgO) + 0.1543 × (content of CaO) + 0.1808 × (content of SrO) + 0.2082 × (content of BaO) + 0.0344 × (12.3 + log １０ 60-log １０ η) is 2.70 to 3.20, 0.0181 × (SiO ２ content) + 0.0004 × (Al ２ O ３ Content of B) + 0.0387 × (B ２ O ３(content of MgO) + 0.1621 × (content of CaO) + 0.1900 × (content of SrO) + 0.2180 × (content of BaO) + 0.0391 × (12.3 + log １０ 60-log １０ η) is 3.13 to 3.63, 0.0177 × (SiO ２ content) + 0.0195 × (Al ２ O ３ Content of B) + 0.0323 × (B ２ O ３ (content of MgO) + 0.1686 × (content of CaO) + 0.1990 × (content of SrO) + 0.2179 × (content of BaO) + 0.0312 × (12.3 + log １０ 60-log １０ η) is 3.45 to 3.95, and 0.0111 × (SiO ２ content) + 0.0250 × (Al ２ O ３ Content of B) + 0.0078 × (B ２ O ３ (content of MgO) + 0.0144 × (content of MgO) + 0.0053 × (content of CaO) + 0.0052 × (content of SrO) + 0.0013 × (content of BaO) − 0.0041 × (12.3 + log １０ 60-log １０ It is preferable that η) satisfies 1.20 to 1.30.

[0076] Here, SiO ２ The content of Al ２ O ３ The content of B ２ O ３ The contents of MgO, MgO, CaO, SrO, and BaO are expressed as mole percentages based on the oxides contained in the obtained glass, and η is a hypothetical viscosity (unit: d Pa s).

[0077] If these requirements are met, it becomes easier to reduce warpage of the glass substrate and the film containing the high refractive index material in the heat treatment step of annealing the high refractive index material attached to the glass substrate while ensuring a process margin.

[0078] 0.0177×(SiO ２ content)−0.0173×(Al ２ O ３ Content of B) + 0.0377 × (B ２ O ３ (content of MgO) + 0.1543 × (content of CaO) + 0.1808 × (content of SrO) + 0.2082 × (content of BaO) + 0.0344 × (12.3 + log １０ 60-log １０ η) is more preferably 2.80 or more, even more preferably 2.90 or more, particularly preferably 2.91 or more, and most preferably 2.92 or more.

[0079] Also, 0.0177 × (SiO ２ content)−0.0173×(Al ２ O ３ Content of B) + 0.0377 × (B ２ O ３ (content of MgO) + 0.1543 × (content of CaO) + 0.1808 × (content of SrO) + 0.2082 × (content of BaO) + 0.0344 × (12.3 + log １０ 60-log １０ η) is more preferably 3.10 or less, even more preferably 3.00 or less, particularly preferably 2.96 or less, and most preferably 2.94 or less.

[0080] 0.0181×(SiO ２ content) + 0.0004 × (Al ２ O ３ Content of B) + 0.0387 × (B ２ O ３ (content of MgO) + 0.1621 × (content of CaO) + 0.1900 × (content of SrO) + 0.2180 × (content of BaO) + 0.0391 × (12.3 + log １０ 60-log １０ η) is more preferably 3.23 or more, even more preferably 3.33 or more, particularly preferably 3.34 or more, and most preferably 3.35 or more.

[0081] Also, 0.0181 × (SiO ２content) + 0.0004 × (Al ２ O ３ Content of B) + 0.0387 × (B ２ O ３ (content of MgO) + 0.1621 × (content of CaO) + 0.1900 × (content of SrO) + 0.2180 × (content of BaO) + 0.0391 × (12.3 + log １０ 60-log １０ η) is more preferably 3.53 or less, even more preferably 3.43 or less, particularly preferably 3.41 or less, and most preferably 3.38 or less.

[0082] 0.0177×(SiO ２ content) + 0.0195 × (Al ２ O ３ Content of B) + 0.0323 × (B ２ O ３ (content of MgO) + 0.1686 × (content of CaO) + 0.1990 × (content of SrO) + 0.2179 × (content of BaO) + 0.0312 × (12.3 + log １０ 60-log １０ η) is more preferably 3.55 or more, even more preferably 3.65 or more, particularly preferably 3.66 or more, and most preferably 3.68 or more.

[0083] Also, 0.0177 × (SiO ２ content) + 0.0195 × (Al ２ O ３ Content of B) + 0.0323 × (B ２ O ３ (content of MgO) + 0.1686 × (content of CaO) + 0.1990 × (content of SrO) + 0.2179 × (content of BaO) + 0.0312 × (12.3 + log １０ 60-log １０ η) is more preferably 3.85 or less, even more preferably 3.73 or less, particularly preferably 3.65 or less, and most preferably 3.71 or less.

[0084] Furthermore, 0.0111 × (SiO ２ content) + 0.0250 × (Al ２ O３ Content of B) + 0.0078 × (B ２ O ３ (content of MgO) + 0.0144 × (content of MgO) + 0.0053 × (content of CaO) + 0.0052 × (content of SrO) + 0.0013 × (content of BaO) − 0.0041 × (12.3 + log １０ 60-log １０ η) is more preferably 1.24 or more.

[0085] Also, 0.0111 × (SiO ２ content) + 0.0250 × (Al ２ O ３ Content of B) + 0.0078 × (B ２ O ３ (content of MgO) + 0.0144 × (content of MgO) + 0.0053 × (content of CaO) + 0.0052 × (content of SrO) + 0.0013 × (content of BaO) − 0.0041 × (12.3 + log １０ 60-log １０ η) is more preferably 1.27 or less.

[0086] The glass substrate has a mass loss in hydrofluoric acid (HF) solution (hereinafter also referred to as HF mass loss) of 0.01 to 0.20 (mg / cm ２ Here, the HF mass loss is the loss per unit area and unit time (mg / cm) when the glass substrate is immersed in a 5 mass % aqueous solution of hydrofluoric acid at 25°C. ２ ) / min).

[0087] After annealing the glass substrate with the high refractive index material, it can be directly incorporated as part of a device. For example, the glass substrate is incorporated into the device as a cover glass. In this case, it is preferable to slim the glass substrate to miniaturize the device. Therefore, it is preferable that the glass substrate has a high slimming rate. The HF mass loss is used as an indicator of the slimming rate of the glass substrate.

[0088] HF mass reduction amount is 0.01 (mg / cm) ２ ) / min or more, the productivity of the slimming step is improved, which is preferable. ２) / minute or less is preferable because defects such as uneven etching depth and loss of smoothness of the glass substrate surface that occur in the slimming step can be prevented.

[0089] The amount of HF mass decrease is 0.07 (mg / cm ２ ) / min or more, and 0.09 (mg / cm ２ ) / min or more is more preferable, and 0.11 (mg / cm ２ ) / min or more is particularly preferred. The HF mass loss is 0.18 (mg / cm ２ ) / min or less is more preferable, and 0.16 (mg / cm ２ ) / min or less is more preferable, and 0.14 (mg / cm ２ ) / minute or less is particularly preferred.

[0090] Glass laminates can be used in optical applications such as optical sensing and optical lenses, for example, as components for face recognition and camera lenses. In this case, if the photoelastic constant of the glass substrate is high, the glass substrate will have birefringence due to stress generated during the device packaging process or during device use. As a result, color changes occur in the light incident on the device, which can lead to poor image quality such as color unevenness.

[0091] In order to prevent such poor image quality, the photoelastic constant of the glass substrate is preferably 37 nm / (MPa cm) or less, more preferably 35.0 nm / (MPa cm) or less, even more preferably 33 nm / (MPa cm) or less, and particularly preferably 29.5 nm / (MPa cm) or less.

[0092] The alpha ray emission rate of the glass substrate is 0.5 C / cm ２ h or less is preferable, and 0.3 C / cm ２ h or less is more preferable, and 0.1 C / cm ２ h or less is particularly preferred, and 0.05 C / cm ２ ・It is most preferable that the number be less than h. The unit C means the number of counts.

[0093] For example, glass laminates can be used as IR cut filters for CCD and CMOS image sensor elements. In this case, when alpha rays emitted from a glass substrate are incident on an element such as an image sensor, the energy of the alpha rays induces hole-electron pairs, potentially causing soft errors that momentarily result in bright or white spots on the image. Therefore, using a glass substrate with low alpha-ray emission can help prevent such defects. Furthermore, the amount of alpha-ray emission can be reduced by using high-purity raw materials with low radioisotope content and low alpha-ray emission as the raw material for the glass substrate. Furthermore, preventing radioisotopes from being mixed into the molten glass from furnace materials in glass manufacturing equipment during the glass melting and fining process can effectively reduce the amount of alpha-ray emission. "Amount of alpha-ray emission" can be measured using a gas flow proportional counter or other measuring device.

[0094] (Surface Treatment of Glass Substrate) The surface of the glass substrate may be partially or entirely surface-treated. If the surface-treated glass substrate is used, impurities (e.g., alkali metal elements) contained in the glass substrate are less likely to elute during the manufacturing process of the glass laminate, and process contamination due to contamination is less likely to occur. The method of surface treatment is not particularly limited, and examples include formation of a protective film (i.e., a protective film for preventing contaminant elution, such as a SiO film) and alkali leaching treatment of the outermost layer.

[0095] (Method for manufacturing glass substrate) The method for manufacturing the glass substrate used in the method for manufacturing the glass laminate of the present disclosure is not particularly limited, and the glass substrate can be manufactured by a known method. The method for manufacturing the glass substrate may include a melting step of heating glass raw materials to obtain molten glass, a fining step of removing bubbles from the molten glass, a forming step of forming the molten glass into a sheet shape to obtain a glass ribbon, and a gradual cooling step of gradual cooling the glass ribbon to room temperature.

[0096] The method for manufacturing a glass substrate may further include treating the surface of the glass substrate (surface treatment step).The method for manufacturing a glass substrate may further include slimming the glass substrate (slimming step), and the slimming step may be, for example, a polishing step of back-grinding or wet etching.

[0097] More specifically, the glass substrate can be manufactured by the glass substrate manufacturing method described in WO 2016 / 125787, for example.

[0098] <High Refractive Index Material> In the present disclosure, a high refractive index material refers to a material having a refractive index of 2.0 or higher. The upper limit of the refractive index is not particularly limited and is, for example, 4.0 or lower. The refractive index may be, for example, 2.0 to 4.0. The refractive index can be measured using a precision refractometer according to the V-block method. The high refractive index material used in the manufacturing method of a glass laminate of the present disclosure can be appropriately selected depending on the application of the glass laminate. For example, silicon may be selected for use in infrared sensing, and titania may be selected for use in a visible light lens. The high refractive index material may be silicon, a metal, or a metal oxide, or may be silicon or an oxide thereof, gallium or an oxide thereof, germanium or an oxide thereof, indium or an oxide thereof, titanium dioxide, sapphire, niobium pentoxide, silicon nitride, gallium nitride, or the like.

[0099] (Thickness) Generally, thicker materials have high rigidity and are less prone to warping, while thinner materials have low rigidity and are more prone to warping. According to the method for producing a glass laminate of the present disclosure, warping is suppressed even when the film containing a high refractive index material (also referred to as a high refractive index material layer) formed on the glass substrate is thin (i.e., when a thin film containing a high refractive index material is formed on the glass substrate). The thickness of the high refractive index material layer is not particularly limited, and from the viewpoint of easily manifesting the effects of the method for producing a glass laminate of the present disclosure, it is preferably 1 μm or less, more preferably 500 nm or less, and even more preferably 200 nm or less. The lower limit of the thickness of the high refractive index material layer is not particularly limited and may be 10 nm or more. The thickness of the high refractive index material layer may be, for example, 10 nm to 1 μm. In the present disclosure, the thickness of the high refractive index material layer is measured by an optical interference thickness measurement method. The optical interference thickness measurement method involves measuring the phase difference of reflected light from the front and back surfaces using, for example, an optical interference thickness measurement device (FlatMaster 200) from Corning-Tropel.

[0100] Average CTEα of high refractive index material at 50 to 100°C before crystallization Ｈｒ５０／１００ is preferably 2.91 to 2.97 ppm / °C.Ｈｒ５０／１００ If the α is 2.91 to 2.97 ppm / °C, the heat treatment with the glass substrate of the present disclosure is easy. Ｈｒ５０／１００ is more preferably 2.92 ppm / °C or more, and even more preferably 2.93 ppm / °C or more. Ｈｒ５０／１００ is more preferably 2.94 ppm / °C or less.

[0101] Average CTEα of high refractive index material from 100 to 200°C before crystallization Ｈｒ１００／２００ is preferably 3.34 to 3.40 ppm / °C. Ｈｒ１００／２００ If the α is 3.34 to 3.40 ppm / °C, the heat treatment with the glass substrate of the present disclosure is easy. Ｈｒ１００／２００ is more preferably 3.36 ppm / °C or more, and even more preferably 3.37 ppm / °C or more. Ｈｒ１００／２００ is more preferably 3.38 ppm / °C or less.

[0102] Average CTEα of high refractive index material at 200-300°C before crystallization Ｈｒ２００／３００ is preferably 3.66 to 3.72 ppm / °C. Ｈｒ２００／３００ If the α is 3.66 to 3.72 ppm / °C, the heat treatment with the glass substrate of the present disclosure is easy. Ｈｒ２００／３００ is more preferably 3.68 ppm / °C or more, and even more preferably 3.69 ppm / °C or more. Ｈｒ２００／３００ is more preferably 3.70 ppm / °C or less.

[0103] <Laminated Substrate> A glass substrate may be formed as a laminated substrate by further bonding a sheet of glass to the glass substrate, for example, with a peelable adhesive layer sandwiched therebetween. That is, the laminated substrate comprises a glass substrate, an adhesive layer, and a sheet of glass, in this order. The sheet glass is preferably the same as the glass substrate from the viewpoint of uniform average CTE and metal impurity content, and the peelable adhesive layer is preferably dry-coated with an inorganic material such as a metal oxide, taking into account heat resistance and film thickness uniformity during the process. When a laminated substrate is used, the thickness of the glass substrate can be considered as the thickness of the laminated substrate (sheet glass + glass substrate). When manufacturing the glass laminate of the present disclosure using a laminated substrate, after forming a film containing a high refractive index material on the glass substrate, or after forming a metasurface structure from the film, the adhesive layer and sheet of glass can be removed by a release treatment. This makes it possible to omit the so-called back-grinding process in the manufacturing process of the glass laminate, in which the thickness of the glass substrate is further reduced by grinding and polishing only on the glass substrate side of the glass laminate (i.e., the surface opposite to the surface on which the film containing the high refractive index material is formed), thereby eliminating yield loss due to back-grinding and dramatically improving the efficiency of the process flow.

[0104] From the viewpoint of thickness uniformity of the laminated substrate, the thickness of the adhesive layer is preferably 1.0 mm or less, more preferably 0.5 mm or less, and even more preferably 0.1 mm or less. The lower limit of the thickness of the adhesive layer may be 5 μm or more. The thickness of the adhesive layer may be, for example, 0.005 to 1.0 mm. From the viewpoint of process transport and workability, the thickness of the sheet glass is preferably 3.0 mm or less, more preferably 1.0 mm or less, and even more preferably 0.5 mm or less. The lower limit of the thickness of the sheet glass may be 0.1 mm or more. The thickness of the sheet glass may be, for example, 0.1 to 3.0 mm. From the viewpoint of flow of the glass substrate alone, the thickness of the laminated substrate is preferably 3.0 mm or less, more preferably 1.0 mm or less, and even more preferably 0.5 mm or less. The lower limit of the thickness of the laminated substrate may be 0.1 mm or more. The thickness of the laminated substrate may be, for example, 0.1 to 3.0 mm.

[0105] <Manufacturing of Glass Laminate> The method for manufacturing a glass laminate of the present disclosure includes forming a film containing a high refractive index material on a glass substrate. In one embodiment, the glass substrate may be cleaned. Forming a film containing a high refractive index material on the glass substrate may include attaching or depositing the high refractive index material on the glass substrate. In one embodiment, for example, a low-pressure chemical vapor deposition (LPCVD) method (e.g., SiH ４ The high refractive index material may be deposited on the glass substrate using a plasma enhanced chemical vapor deposition (PECVD) process, a high-density plasma chemical vapor deposition (HDPCVD) process, and / or any of a wide variety of alternative chemical vapor deposition (CVD) processes. The high refractive index material may be deposited on the glass substrate using a plasma enhanced chemical vapor deposition (PECVD) process, a high-density plasma chemical vapor deposition (HDPCVD) process, and / or any of a wide variety of alternative chemical vapor deposition (CVD) processes. The high refractive index material may be deposited such that the film comprising the high refractive index material has a thickness of 210 to 250 nm.

[0106] Forming a film including a high refractive index material on a glass substrate may include annealing the high refractive index material deposited on the glass substrate (also referred to as a heat treatment process). Annealing the high refractive index material crystallizes the high refractive index material to form a film. The deposited high refractive index material is annealed at an appropriate temperature for a time sufficient to reduce absorption losses and improve the transmission efficiency of the glass laminate. That is, rather than simply annealing to crystallize, harden, or stabilize the high refractive index material, the annealing process is carried out at an appropriate temperature and for a sufficient amount of time for the specific purpose of reducing absorption losses of optical radiation within a target operating bandwidth. In various embodiments, high refractive index materials that are not generally considered practical for use at optical frequencies are preferably annealed to reduce absorption losses by as much as 35%, thereby making the high refractive index material suitable for use at optical frequencies. For example, if the high refractive index material is polysilicon, the polysilicon may be annealed at a temperature of 500 to 1100°C for 30 to 90 minutes, depending on the thickness of the polysilicon, the target operating frequency band, and other target property functionality. For example, the optical properties of high refractive index materials may be improved by adding an inert atmosphere gas (e.g., argon, N) to reduce the extinction coefficient at shorter wavelengths. ２ This may be improved by annealing the high refractive index material at temperatures above 1000° C. for an hour or more in a refrigerated or refrigerated oven (eg, a refrigerated or refrigerated room).

[0107] A film containing a high refractive index material formed on a glass substrate may be formed into a metasurface structure by photolithography (e.g., deep ultraviolet lithography), electron beam lithography, or nanoimprint lithography.

[0108] The method of manufacturing a glass laminate of the present disclosure may include applying a resist (e.g., photoresist) onto the annealed layer of high refractive index material. In one embodiment, the resist may be a negative photoresist, such as Ma-N2403, or a positive photoresist, in which the masking and etching processes may be reversed or otherwise modified. In one embodiment, a lithography process, such as electron beam lithography (EBL) or another nanolithography technique, is used to define a pattern of deflector element diameters included in the glass laminate. The pattern of deflector element diameters may be repeated one or more times, and the pattern of deflector element diameters may be selected to provide a target deflection pattern for optical radiation within a target operating bandwidth.

[0109] The method for manufacturing a glass laminate of the present disclosure may also include developing the resist. In one embodiment, electron beam lithography (e-beam lithography: EBL) of the photoresist, developing the photoresist, and hard baking the photoresist (e.g., to generate a hard-baked photoresist pattern) may be performed. The photoresist is specifically developed to have a mask pattern corresponding to a target array of pillar diameters for the glass laminate. The target array of pillars may be a two-dimensional array of pillars with a pattern of diameters as contemplated and described in this disclosure or in the previously cited publications incorporated by reference. The target array of pillars is selected to achieve a specific polarization response for a targeted wavelength range according to either a reflective glass stack design, a diffractive glass stack design, a refractive glass stack design, or a filtering glass stack design.

[0110] The method of manufacturing a glass laminate of the present disclosure may include etching the annealed high refractive index material according to a mask pattern of the developed photoresist. In one embodiment, a partial etch of the high refractive index material where the resist was not developed may be performed. This first etch removes a portion of the high refractive index material between pillars protected by the photoresist cap on top, but does not etch the high refractive index material down to the glass substrate. This partial etch thus produces partially formed nanopillars of high refractive index material with a layer of unetched high refractive index material between adjacent partially formed pillars (nanopillars). According to various embodiments, this first etch may include a reactive ion etching (RIE) process (e.g., using HBr and / or Cl). ２ The method may include an RIE method using a fluorine atom or an iodine atom.

[0111] In one embodiment, the resist may be removed to reveal pillars (or other shaped deflector elements) of high refractive index material extending from the glass substrate. In one embodiment, not only one-dimensional rows of pillars can be fabricated, but two-dimensional arrays of pillars can also be fabricated. This fabrication method may be used to fabricate each glass stack pixel or glass stack subpixel separately, after which the individual glass stack pixels or glass stack subpixels can be bonded together. Alternatively, this fabrication method may be used to fabricate a complete two-dimensional array of glass stack pixels or glass stack subpixels as a single unit.

[0112] In one embodiment, removal of the photoresist mask layer may be performed to expose the partially formed pillars of high refractive index material and the unetched layer of high refractive index material along the substrate. The photoresist removal process may include, for example, O ２ Plasma removal, H ２Plasma stripping, application of 1-methyl-2-pyrrolidone (NMP), application of dimethyl sulfoxide (DMSO), combinations thereof, and / or alternative photoresist removal processes may be included.

[0113] In one embodiment, a second etch of the high refractive index material may be performed to remove the unetched layer of high refractive index material and complete the formation of nanopillars extending from the substrate. This second etch of the high refractive index material may slightly reduce the height of the partially formed nanopillars. Furthermore, it may completely remove any remaining photoresist from the nanopillars. This two-step etching process allows the second etch to set the height of the pillars to achieve the target pillar height. As detailed in this disclosure, the photoresist is removed between the first and second etches.

[0114] In one embodiment, a glass laminate may be manufactured having an array of passive deflector elements of various diameters extending from a substrate.

[0115] According to various embodiments, the glass stack pattern includes a rectangular (e.g., square) array of pillars of varying diameters corresponding to a target reflective pattern. In some cases, manufacturing techniques may limit the maximum size of a rectangular cell having an array of pillars. For example, tiles measuring approximately 1 cm on each side may be fabricated using a given manufacturing process (e.g., a CMOS process). Any number of these tiles may then be combined to form a glass stack having a rectangular aperture with a target length and width. While electron beam lithography is limited to device fabrication at the micron scale, or even millimeter scale, repeated tiling of the same pillar diameter array and combining adjacent tiles enables the fabrication of much larger devices.

[0116] For example, an array of pillars may be defined with various diameters to fit within micron- or millimeter-scale apertures. During fabrication, the pattern may be repeated as many times as desired to create much larger devices. For example, using a CMOS process, a device with a diameter of approximately 1.2 cm may be fabricated. ２ A 300 mm glass substrate can be used in a CMOS process to produce a glass laminate of approximately 1 cm ２ Multiple individual rectangular glass laminates can be produced, ranging in size from 100 mm to 120 mm. Glass laminates manufactured using CMOS fabrication techniques can be appropriately sized for use in smaller electronic devices (e.g., cell phones, computers, personal electronic devices, cameras, etc.).

[0117] In contrast, deep ultraviolet lithography may be used to produce glass stacks over the entire surface of a 300 mm glass substrate. Again, very small (e.g., micron- or millimeter-scale) square tiles may be replicated as many times as desired using the deep ultraviolet lithography process to produce rectangular glass stacks on the surface of the glass substrate. Display optics for satellites or other imaging devices may use relatively large glass stacks manufactured using deep ultraviolet lithography techniques.

[0118] In yet another embodiment, the tiles are replicated in a nanoimprint lithography process to form a 1 m ２ The above glass laminates may be produced by a nanoimprint lithography process, where a base tile defining an array of pillars with varying diameters can be replicated as many times as desired to produce glass laminates with target lengths and widths.

[0119] For example, nanoimprint lithography may be used to fabricate a glass laminate directly over an RGB display or directly over a digital imaging sensor. A glass laminate fabricated over an RGB display can deflect light from each individual LED in a target direction perpendicular to the plane of the display. This glass laminate can increase the effective brightness of each pixel and reduce crosstalk between individual red, green, and blue subpixels.

[0120] In one embodiment, the glass laminate associated with the blue subpixel (or other color channel subpixel) may be configured to modify the amount of light scattered during off-angle viewing of an RGB display. For example, blue light may be scattered more off-angle (e.g., in a direction other than perpendicular to the plane of the display) than the red and green color channels. Thus, a viewer of an RGB display may perceive a color shift toward the blue spectrum during off-angle viewing. In this manner, the glass laminate on an RGB display may be configured to normalize or equalize the amount of light scattered off-angle from each of the red, green, and blue subpixels.

[0121] According to various embodiments, the design of the array of pillars in each glass laminate is selected for compatibility with a particular manufacturing process. For example, the ratio of the height of each pillar to its diameter (or width) may be less than 3. Features with such aspect ratios can be lithographically defined and etched using CMOS processes. Similarly, high refractive index materials are generally considered to be CMOS compatible. However, other materials, such as titanium dioxide, are not used in the fabrication of glass laminates to maintain manufacturing process compatibility.

[0122] In one embodiment, a Bayer color filter implemented using glass stacks overlaid on an imaging sensor may be fabricated and may have red, green, and blue color filters. In one embodiment, the glass stacks described in this disclosure may enhance existing color filters (e.g., Bayer color filters, etc.) of a digital imaging sensor. For example, a discrete glass stack having a green frequency response may be matched to focus light radiation onto green subpixel color filters of an existing color filter array on the digital imaging sensor. Similarly, glass stacks having red and blue frequency responses may be matched to focus or otherwise direct light radiation onto red and blue subpixel color filters, respectively, of an existing color filter array on a digital imaging sensor or LED display.

[0123] In one embodiment, a narrowband pixel-mapping color filter implemented using a glass laminate may be fabricated. The glass laminate, or an array of multiple glass laminates, may be utilized in conjunction with a digital imaging sensor that does not have a traditional color filter array. In one embodiment, the correspondence of the red, green, and blue pixels of the glass laminate is used to provide a one-to-one correspondence to the sub-pixel detectors of the underlying digital imaging sensor.

[0124] For example, each of the three red glass laminates may be associated with a corresponding red sub-pixel detector element of the underlying digital imaging sensor. Similarly, each of the three green glass laminates may be associated with a separate green sub-pixel detector element of the digital imaging sensor, and each of the three blue glass laminates may be associated with a separate blue sub-pixel detector element of the digital imaging sensor. The effective bandwidth (e.g., the 3Db bandwidth) of each glass laminate may be in the range of 50-80 nm. Thus, a red glass laminate centered at 650 nm may propagate optical radiation between 625-675 nm, for example. For example, green and blue glass laminates centered at 535 nm and 490 nm, respectively, may propagate optical radiation of a similar bandwidth to the sub-pixel detector elements of the underlying digital imaging sensor.

[0125] In one embodiment, a subpixel multi-band color filter implemented using glass stacks may be fabricated, in which each glass stack is replaced with an array of nine subpixel glass stacks. The underlying digital imaging sensor may still include only nine subpixel detector elements. Thus, each array of nine subpixel glass stacks directs light radiation onto a single subpixel detector element of the digital imaging sensor.

[0126] In one embodiment, the red glass stack is replaced with an array of nine subpixel glass stacks. The central subpixel glass stack exhibits a central operating bandwidth of 650 nm. The surrounding eight subpixel glass stacks have operating bandwidths centered at wavelengths offset from the central subpixel glass stack by ±20 nm, ±15 nm, ±10 nm, and ±5 nm. Collectively, the array of nine subpixel glass stacks transmits a wider bandwidth of optical radiation to the subpixel detector elements of the underlying digital imaging sensor than would be possible using a single glass stack. Using the exemplary effective operating bandwidth of 50 nm above, the nine subpixel glass stacks can transmit optical radiation from 605 to 695 nm to the subpixel detector elements of the underlying digital imaging sensor.

[0127] In one embodiment, each glass stack can be replaced with an array of N subpixel glass stacks, where N is an integer value greater than 2. The tuning frequency offset of each subpixel glass stack of the plurality of subpixel glass stacks can be selected to achieve a target collective operating bandwidth.

[0128] In one embodiment, a subwavelength multi-band color filter implemented using glass stacks may be fabricated. The subwavelength multi-band color filter includes a glass stack filter for red, a glass stack filter for green, and a glass stack filter for blue that are subwavelength in size. As described above, the subwavelength multi-band color filter may effectively function as a two-dimensional array of flat prisms that directs red, green, and blue light emissions to corresponding sub-pixel detector elements of an underlying digital imaging sensor.

[0129] In one embodiment, an exemplary display system may be fabricated utilizing input and output glass stack couplers in conjunction with a waveguide. A controller and RGB laser assembly transmit optical radiation to a display engine that generates an RGB display. The input glass stack coupler combines the generated RGB optical radiation for transmission along the length of a waveguide. The output glass stack coupler receives the transmitted optical radiation and separates it from the waveguide for visualization to a user's eye (e.g., via frequency-selective focusing onto a target plane).

[0130] The method for manufacturing a glass laminate of the present disclosure may include a step of slimming a glass substrate having a metasurface structure. The slimming step may be, for example, a back-grinding polishing step or wet etching. For example, quartz glass has a slow back-grinding rate and is easily broken, but B ２ O ３ , P ２ O ５ , GeO ２ , and Al ２ O ３ The back grinding rate can be increased by adding at least one selected from the group consisting of: The glass substrate may be thinned to 0.2 to 0.4 mm by back grinding.

[0131] The method for manufacturing a glass laminate of the present disclosure may include dicing a glass substrate having a metasurface structure. The dicing method is not particularly limited and may be stealth dicing or wet blade dicing.

[0132] The glass laminate of the present disclosure is manufactured by the method for manufacturing a glass laminate of the present disclosure. The glass laminate of the present disclosure includes a glass substrate and a metasurface structure including a high refractive index material, wherein the total amount of alkali metal elements in the glass substrate is 200 ppm or less by mass, and the difference in average CTE between the glass substrate and the high refractive index material before crystallization at 50 to 200°C is within ±0.5 ppm / K.

[0133] The descriptions regarding the glass laminate, glass substrate, high refractive index material, alkali metal element, average CTE, etc. of the glass laminate of the present disclosure are the same as those described above in the manufacturing method of the glass laminate of the present disclosure. The glass laminate of the present disclosure is preferably a metalens.

[0134] The glass laminate of the present disclosure has a metasurface structure. The metasurface structure is formed on a glass substrate. The glass laminate can function as a lens by controlling the phase distribution of light. The metasurface structure is preferably a nanostructure, and more preferably a nanopillar structure.

[0135] The metasurface structure may be arranged two-dimensionally in the xy plane. The shape of the metasurface structure may be a rotationally symmetric shape such as a cylindrical shape or a square prism shape, or an asymmetric nanofin shape. The metasurface structure may be, for example, a cylinder with a diameter φ and a height H. In the glass laminate, this metasurface structure may be arranged periodically with a period U. In the metasurface structure, the diameter φ may have multiple values. In the metasurface structure, the height H may have only one value or multiple values. The diameter φ and the period U may be equal to or less than the wavelength of the light used.

[0136] The metasurface structures are arranged, for example, in a lattice pattern. The height H of the metasurface structures may be 10 to 1000 nm. The size of the metasurface structures is about 1 / 10 of the wavelength to be affected, and may be 100 to 1000 nm when acting in the near-infrared wavelength range, for example. The spacing L between adjacent metasurface structures may be 100 to 1000 nm.

[0137] The glass laminate can control the phase distribution of light by adjusting the arrangement of the metasurface structures, as well as the size and period of each metasurface structure. By adjusting the size and period of the metasurface structures, the focal length of the glass laminate can be made the same regardless of the wavelength of the incident light.

[0138] A glass laminate was produced by the following method: The glass substrates and high refractive index materials used in producing the glass laminate were as follows.

[0139] <Glass Substrate> An alkali-free glass substrate containing alkali metal elements in a total amount of 200 ppm or less by mass is prepared as the glass substrate. The contents of Ti, Cu, Cr, Ce, Ni, and Zn contained in the glass substrate are each 20 ppm or less by mass. The total amount of Fe contained in the glass substrate is 100 ppm or less by mass. The composition of the glass substrate, expressed in mole percentage on an oxide basis, is SiO ２ :50~75%, Al ２ O ３ : 6-16%, B ２ O ３ : 0 to 15%, MgO: 0 to 15%, CaO: 0 to 13%, SrO: 0 to 11%, and BaO: 0 to 9.5%. The difference in average CTE between the glass substrate and a high refractive index material (described later) before crystallization at 50 to 200°C is within ±0.5 ppm / K.

[0140] The details of the glass substrate are as follows: Size: main surface area 0.015 m ２ Thickness: 0.5 to 3.0 mm Thickness deviation (TTV): 5 μm or less Surface roughness (Ra): 5 nm or less

[0141] <High Refractive Index Material> Silicon is prepared as the high refractive index material.

[0142] <Manufacturing a Glass Laminate> A high refractive index material is coated on the surface of a glass substrate using a chemical vapor deposition apparatus. The high refractive index material attached or deposited on the glass substrate is annealed (heat treatment process) to crystallize the high refractive index material, forming a film (1 μm thick) containing the high refractive index material on the glass substrate. The thickness of the film containing the high refractive index material is 0.00001 to 0.01 times the thickness of the glass substrate. The warpage of the glass substrate on which the film containing the high refractive index material is formed is 50 μm or less. A resist is applied to the annealed layer of high refractive index material and developed. The annealed high refractive index material is etched using photolithography, electron beam lithography, or nanoimprint lithography according to the mask pattern of the developed resist to form a metasurface structure.

[0143] That is, according to the present disclosure, a method for manufacturing a glass laminate can be obtained in which warping of the glass substrate and the film formed on the glass substrate is suppressed and process contamination due to alkali metal ions released from the glass substrate is reduced.

[0144] The glass laminate obtained by the above method is a glass laminate including a glass substrate and a metasurface structure in which a high refractive index material is crystallized, wherein the glass substrate has a total amount of alkali metal elements of 200 ppm or less by mass, and the difference in average CTE between the glass substrate and the high refractive index material before crystallization at 50 to 200°C is within ±0.5 ppm / K.

[0145] The disclosure of Japanese Patent Application No. 2024-154986, filed on September 9, 2024, is incorporated herein by reference in its entirety. In addition, all documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard were specifically and individually indicated to be incorporated by reference.

[0146] As described above, the method for manufacturing a glass laminate according to the present disclosure suppresses warping of the glass substrate and the film formed on the glass substrate, and reduces process contamination due to alkali metal ions released from the glass substrate, and a glass laminate manufactured by the method can be obtained. The glass laminate according to the present disclosure is used in applications such as meta-optical components (e.g., metalenses), thermal control components using metamaterial technology, and electromagnetic wave control components for reconfigurable intelligent surfaces (RIS) including metasurface technology.

Claims

1. A method for manufacturing a glass laminate, comprising forming a film containing a high refractive index material on a glass substrate, forming a metasurface structure from the film, wherein the total amount of alkali metal elements in the glass substrate is 200 ppm or less by mass, and the difference in average linear expansion coefficient between the glass substrate and the high refractive index material before crystallization at 50 to 200°C is within ±0.5 ppm / K.

2. The method for producing a glass laminate according to claim 1, wherein the glass substrate is an alkali-free glass substrate.

3. The method for producing a glass laminate according to claim 1 or 2, wherein the difference in average linear expansion coefficient between the glass substrate and the high refractive index material before crystallization is within ±0.3 ppm / K.

4. The method for producing a glass laminate according to claim 1 or 2, wherein the content of each of Ti, Cu, Cr, Ce, Ni, and Zn contained in the glass substrate is 20 ppm or less by mass.

5. The method for producing a glass laminate according to claim 1 or 2, wherein the content of Fe contained in the glass substrate is 100 ppm or less by mass.

6. The area of ​​the main surface of the glass substrate is 0.015 m². ２ The method for producing a glass laminate according to claim 1 or 2, wherein the method is as described above.

7. The area of ​​the main surface of the glass substrate is 0.025 m². ２ The method for producing a glass laminate according to claim 1 or 2, wherein the method is as described above.

8. The method for producing a glass laminate according to claim 1 or 2, wherein the glass substrate has a thickness of 0.5 to 3.0 mm.

9. The method for producing a glass laminate according to claim 1 or 2, wherein the thickness of the film containing a high refractive index material is 0.00001 to 0.01 times the thickness of the glass substrate.

10. The method for producing a glass laminate according to claim 1 or 2, wherein the thickness deviation of the glass substrate is 5 μm or less and the surface roughness of the glass substrate is 5 nm or less.

11. The method for producing a glass laminate according to claim 1 or 2, wherein the thickness deviation of the glass substrate is 3 μm or less, and the surface roughness of the glass substrate is 3 nm or less.

12. The method for producing a glass laminate according to claim 1 or 2, wherein the amount of warpage of the glass substrate on which the film is formed, as measured in accordance with JIS B 0621, is 50 μm or less.

13. The method for producing a glass laminate according to claim 1 or 2, wherein the amount of warpage of the glass substrate on which the film is formed, measured in accordance with JIS B 0621, is 30 μm or less.

14. The method for producing a glass laminate according to claim 1 or 2, wherein the high refractive index material is silicon or its oxide, gallium or its oxide, germanium or its oxide, indium or its oxide, titanium dioxide, sapphire, niobium pentoxide, silicon nitride, or gallium nitride.

15. A method for manufacturing a glass laminate according to claim 1 or 2, comprising forming a metasurface structure on the glass substrate by photolithography, electron beam lithography, or nanoimprint lithography on the film.

16. The method for manufacturing a glass laminate according to claim 1 or 2, wherein the surface roughness of the end face of the glass substrate is 50 nm or less.

17. The density of the glass substrate is 2.20 g / cm ３ 2.60g / cm or more ３ The method for producing a glass laminate according to claim 1 or 2, wherein:

18. The method for manufacturing a glass laminate according to claim 1 or 2, wherein the thickness of the film containing the high refractive index material is 1 μm or less.

19. A glass laminate having a glass substrate and a metasurface structure including a high refractive index material, wherein the glass substrate has a total amount of alkali metal elements of 200 ppm or less by mass, and the difference in average linear expansion coefficient between the glass substrate and the high refractive index material before crystallization at 50 to 200°C is within ±0.5 ppm / K.