Method for producing glass, and glass

Abstract

Provided is a method for producing glass that makes it possible to produce glass having a plurality of vias and a good hole shape, and makes it possible to reduce variations in hole size. This method for producing glass having a plurality of vias (140) comprises a step for forming the plurality of vias (140) by etching glass having a modified part (120), and the coefficient of variation in etching temperature after 60 minutes has elapsed from the start of etching is 0.001-0.025.

Description

Glass manufacturing method and glass

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

[0002] In recent years, in the semiconductor field, performance improvements through silicon microfabrication are approaching their physical and cost limits. For this reason, there has been active research into improving performance through advanced semiconductor post-processing and the materials used therein. Glass plates with micro-through holes (Through Glass Via, TGV) are in demand for many applications, such as glass interposers and glass core substrates, and manufacturing methods for these are being researched. For example, there is a method in which a glass substrate is modified by irradiating it with a laser, and then the modified area is anisotropically processed in a location-selective manner by etching with a chemical solution.

[0003] In glass substrates with micropores, there are cases where hundreds to tens of millions of holes are formed in a single glass substrate, and in such cases, quality defects due to variations in the shapes of the countless holes become an issue.

[0004] When forming micropores in a glass sheet by chemical treatment, it is believed that temperature control of the chemical solution affects quality. For example, in order to maintain the temperature of the etching solution in an etching tank at a constant temperature, suppress fluctuations in the etching rate, and reduce variations in the etching treatment of the glass sheet, a glass sheet manufacturing apparatus has been disclosed that includes, for example, a first temperature control device that adjusts the temperature of the etching solution in the etching tank and a second temperature control device that adjusts the temperature of the replenisher solution in the replenisher tank (see, for example, Patent Document 1).

[0005] International Publication No. 2022 / 223716

[0006] An object of one embodiment of the present disclosure is to provide a method for manufacturing glass having a plurality of vias, which has a good hole shape and can reduce variation in hole diameter.

[0007] A method for manufacturing glass according to an embodiment of the present disclosure is a method for manufacturing glass having a plurality of vias, in which glass having a modified portion is etched to form the plurality of vias, and the coefficient of variation of the etching temperature after 60 minutes have elapsed since the start of etching is 0.001 or more and 0.025 or less.

[0008] According to one embodiment of the present disclosure, it is possible to provide a method for manufacturing glass having a plurality of vias, which has a good hole shape and can reduce variation in hole diameter.

[0009] Fig. 1 is a schematic diagram showing the flow of the method for manufacturing glass according to the first embodiment. Fig. 2 is a schematic diagram showing the flow of the method for manufacturing glass according to the first embodiment. Fig. 3 is a schematic diagram showing the flow of the method for manufacturing glass according to the first embodiment. Fig. 4 is a schematic diagram showing the flow of the method for manufacturing glass according to the second embodiment. Fig. 5 is a schematic diagram showing the flow of the method for manufacturing glass according to the second embodiment. Fig. 6 is a graph showing the relationship between the coefficient of variation of the etching temperature and the coefficient of variation of the top hole diameter in Examples 1 to 4.

[0010] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In each drawing, the same or similar components are denoted by the same reference numerals, and their description may be omitted. In the specification, the symbol "to" indicating a numerical range means that the numerical values ​​before and after it are included as the lower and upper limits. The numerical range includes the range rounded up or down. Hereinafter, the composition range of each component of the glass is expressed in mol% based on the oxide.

[0011] (Glass Manufacturing Method) A glass manufacturing method of the present embodiment is a method for manufacturing glass having a plurality of vias, which includes etching glass having modified portions to form the plurality of vias, and may further include irradiating a laser to a position on the glass substrate where a via is to be formed, as necessary. The coefficient of variation of the etching temperature after 60 minutes from the start of etching is 0.001 or more and 0.025 or less.

[0012] In conventional wet etching, calcium ions, magnesium ions, and the like eluted from glass such as aluminosilicate glass form precipitates such as aluminates, silicates, and hydroxides, inhibiting etching inside the holes. Furthermore, the flow inside the holes forms a closed vortex, and as etching progresses, precipitates accumulate, and the base component and complexing agent decrease, resulting in a decrease in the etching rate (see, for example, Journal of the Electrochemical Society, 1983, 130.8: 1722). Because the etching reaction proceeds independently for each via, variations in the degree of etching progress among multiple vias occur, resulting in variations in hole diameter.

[0013] Patent Document 1, which discloses a conventional glass plate manufacturing apparatus, describes how the temperature control of the etching solution and replenisher solution at constant temperatures using the manufacturing apparatus reduces variations in the processing of multiple recesses or grooves within the same glass plate, but does not provide specific numerical values, such as a small standard deviation in the hole diameters of the multiple recesses, and the specific effects of controlling the temperature at a constant value are unclear. Furthermore, there is no mention of variations in the recesses between multiple glass plates in the same batch.

[0014] The present inventors have conducted extensive research to solve the problems of the conventional techniques and the above-mentioned problems, and as a result, have unexpectedly found that if the temperature fluctuation during etching is too large or too small, the variation in hole diameter increases.The present inventors have then found that a method for manufacturing glass having a plurality of vias can be provided, in which glass having a modified portion is etched to form the plurality of vias, and the coefficient of variation of the etching temperature after 60 minutes from the start of etching is 0.001 or more and 0.025 or less, thereby achieving a good hole shape and reduced variation in hole diameter, and have completed the present invention.

[0015] The via may be a through via that penetrates from one surface of the glass to the other surface, or a non-through via that has an opening on one surface of the glass and no opening on the other surface, and either can be selected appropriately depending on the purpose.

[0016] First Embodiment A method for manufacturing glass according to a first embodiment will be described below with reference to Figures 1 to 3. Figures 1 to 3 are schematic diagrams showing the flow of the method for manufacturing glass according to the first embodiment, illustrating aspects of the method for manufacturing glass having through vias. The method for manufacturing glass according to the first embodiment includes, for example, steps S101 to S102. In step S101, a laser is irradiated onto a glass substrate at a position where a via is to be formed, thereby forming a modified portion. In step S102, the glass having the modified portion is etched to form the plurality of vias.

[0017] <S101> In step S101, a laser is irradiated onto a position on the glass substrate where a via is to be formed to form a modified portion. This forms a modified portion by modifying the position where the via is to be formed, and glass having the modified portion is formed. The position where the via is to be formed is modified by receiving energy from the laser irradiation, and becomes a modified portion that has a property of being easily etched.

[0018] First, a glass substrate 110 is prepared. As shown in FIG. 1, the glass substrate 110 has a first surface 112 and a second surface 114 opposite to the first surface 112.

[0019] -Glass- The glass used for the glass substrate 110 is not particularly limited and can be appropriately selected depending on the purpose. ２ O, Na ２ O.K. ２ Aluminosilicate glass containing at least one selected from the group consisting of O, MgO, CaO, SrO, and BaO is preferred. ２ O, Na ２ O and K ２ It is more preferable that the total content of O is 0 mol% to 10 mol%, and the total content of MgO, CaO, SrO, and BaO is 0 mol% to 30 mol%. The elements contained in the glass are not particularly limited, and any element may be contained depending on the desired physical properties. In this specification, glass also includes crystallized glass.

[0020] SiO in the glass ２The content of Al in the glass is preferably 40 mol % to 99 mol %, more preferably 55 mol % to 90 mol %, and particularly preferably 60 mol % to 85 mol %, from the viewpoint of improving the flatness rate and straightness. ２ O ３ The content of B in the glass is preferably 1 mol % to 40 mol %, more preferably 1 mol % to 30 mol %, and even more preferably 3 mol % to 20 mol %, from the viewpoint of improving the flatness rate and straightness. ２ O ３ From the viewpoint of enhancing the planar rate and straightness, the content is preferably 0 mol % to 30 mol %, more preferably 1 mol % to 25 mol %, even more preferably 3 mol % to 20 mol %, and particularly preferably 5 mol % to 15 mol %.

[0021] SiO ２ , Al ２ O ３ , and / or B ２ O ３ has the effect of forming a glass network, and Li ２ O, Na ２ O.K. ２ O, MgO, CaO, SrO, and / or BaO have the effect of modifying the glass network and are generally referred to as network modifier oxides. The glass may be appropriately selected depending on the intended use, taking into consideration the CTE, refractive index, density, Young's modulus, relative dielectric constant, dielectric loss tangent, etc.

[0022] The glass substrate 110 may be a laminate having additional layers such as inorganic films or organic films. When the glass is used for packaging semiconductor devices, alkali-free glass is preferred. This is because alkali-containing glass may precipitate alkali components in the glass and adversely affect the semiconductor devices.

[0023] The average thickness of the glass substrate 110 is not particularly limited and can be appropriately selected depending on the purpose, and may be, for example, 0.05 mm to 3.0 mm.

[0024] Next, a laser is irradiated from the first surface 112 of the glass substrate 110 to a position where a via is to be formed, thereby forming a modified portion 120. Figure 2 shows a schematic cross-sectional view of the glass substrate 110 having the modified portion 120 after laser irradiation. When manufacturing glass having through vias, a plurality of modified portions 120 are formed that communicate from the first surface 112 to the second surface 114. In the modified portion 120, the opening in the first surface 112 is referred to as a first initial opening 122, and the opening in the second surface 114 is referred to as a second initial opening 124.

[0025] The via formation position and modified portion may be a through via formation position and modified portion (e.g., 120 in FIG. 2) that communicates through the thickness direction of the glass substrate, or a non-through via formation position and modified portion (e.g., 230 in FIG. 4) that communicates from one surface of the glass substrate to a predetermined depth, either of which can be appropriately selected depending on the purpose. Through vias may be connected to each other to form a through via with an irregular shape, or non-through vias may be connected to each other to form a cavity-shaped, pocket-shaped, or groove-shaped via. However, in this specification, shapes formed by connecting vias to each other are not subject to evaluation of hole diameter variation. This is because, for example, evaluating a large number of fine vias and large cavities in parallel may result in an abnormally large coefficient of variation, which is contrary to the intent of the present invention.

[0026] The laser is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include a green laser and a UV laser. Furthermore, as a laser irradiation method, it is preferable to use a short-pulse laser (e.g., a picosecond laser, a nanosecond laser, or a femtosecond laser). Specifically, a modified portion can be formed by irradiating aluminosilicate glass having an average thickness of 1.1 mm with a green picosecond laser (e.g., a wavelength of 532 nm, a pulse width of 10 ps) with pulse energy of 40 μJ to 300 μJ, with one to several shots per planned formation position (e.g., 100 μJ, one shot).

[0027] <S102> In step S102, the glass having the modified portion is etched to form the plurality of vias, thereby manufacturing a glass having a plurality of vias.

[0028] In step S102, the glass substrate 110 having the modified portion 120 is etched using an etching solution composition to form a plurality of through vias 140. At this time, the first initial opening 122 is expanded to form a first opening 142, and the second initial opening 124 is expanded to form a second opening 144. Note that during the etching process, the surface of the glass substrate 110 is also etched, and the thickness of the glass substrate 110 is reduced from the thickness t before etching. ０ From t １ Figure 3 shows a schematic cross-sectional view of the glass with through via 140 after etching.

[0029] Therefore, the first surface 112 and the second surface 114 of the glass substrate 110 are each transformed into a new surface after the etching process. However, in order to avoid complication of explanation in this application, the mutually opposing surfaces of the glass substrate 110 after the etching process will be referred to as the "first surface 112" and the "second surface 114."

[0030] In this manner, glass having through vias 140 can be manufactured as shown in FIG.

[0031] The method for etching glass is not particularly limited as long as an etching solution composition for glass etching is used, and any known method can be appropriately selected depending on the purpose, but it is preferable to immerse the glass in the etching solution composition. The etching temperature is preferably 20°C to 150°C, more preferably 50°C to 120°C, and the etching time is preferably 2 hours to 240 hours, more preferably 5 hours to 200 hours.

[0032] The variation in etching temperature can be evaluated by the coefficient of variation, i.e., standard deviation / average value. The standard deviation and average value may be calculated from the measured values ​​of the etching temperature. The coefficient of variation of the etching temperature after 60 minutes has elapsed since the start of etching is 0.001 or more and 0.025 or less. The lower limit is more preferably 0.0015 or more, even more preferably 0.002 or more, and particularly preferably 0.003 or more. The upper limit is more preferably 0.024 or less, even more preferably 0.023 or less, and particularly preferably 0.022 or less.

[0033] Here, the first 60 minutes from the start of etching to the end of etching are excluded from consideration due to the effects of temperature control overshoot and temperature equilibration. The time period for calculating the coefficient of variation of the etching temperature is preferably from 60 minutes after the start of etching to the end of etching, but the end of etching need not be taken into consideration. It may also be from 60 minutes after the start of etching to a predetermined time. The predetermined time may be any time sufficient for the etching reaction of each via to proceed without variation due to the effects of this embodiment, and may be any time between 5 hours and 200 hours. Furthermore, the time period is preferably 20% or more of the etching time, more preferably 30% or more, 40% or more, or 50% or more. The data measurement interval for calculating the coefficient of variation of the etching temperature is preferably 1 minute to prevent the influence of noise.

[0034] The etching temperature profile may be a constant temperature (single-stage) profile or a multi-stage profile. In the case of a multi-stage profile, the time period for calculating the variation coefficient of the etching temperature can be set to 60 minutes after the start of the temperature increase and temperature decrease etching, and up to a predetermined time period after the temperature profile reaches a plateau. For example, when the temperature T １ ± coefficient of variation, first stage, temperature T ２ ± the second stage with the coefficient of variation, ... temperature T ｎ In the case of a multi-stage profile in which the temperature is changed in the order of n stages with ±coefficient of variation, the calculation may be based on the predetermined time of only the plateau portion of the first stage without considering the initial 60 minutes from the start of etching until 60 minutes have elapsed and the temperature rising and falling processes, or may be based on the predetermined time of the plateau portions of the first stage, second stage, ..., nth stage.

[0035] To implement a multi-stage profile, a method may be used in which a plurality of tanks with different temperatures are prepared and the glass substrate is moved between them. The temperature control method for intentionally varying the temperature is not limited in any way, but for example, a temperature regulator (program controller) equipped with a thermocouple may be used, and any control method such as feedback control or feedforward control may be used to appropriately adjust parameters, thereby enabling etching to be performed under desired temperature variation conditions.

[0036] From the viewpoint of refreshing the etching solution composition inside the holes in the glass during etching, it is preferable to flow the etching solution composition. Suitable examples include a method of filling a closed space with the etching solution composition and etching while applying liquid pressure, as described in JP 2020-001959 A; a method of etching by applying ultrasonic waves (for example, 40 kHz to 192 kHz) to a glass substrate, as described in JP 2016-534017 A; a method of etching while stirring the etching solution composition with a vibrator immersed in the etching solution composition, as described in JP 2020-066551 A; and a method of etching under conditions in which the average relative speed of the etching solution composition to the glass is faster in the second etching step than in the first etching step, as described in JP 2023-082984 A.

[0037] - Etching Solution Composition - The etching solution composition for glass etching is not particularly limited and can be appropriately selected depending on the purpose. However, it is preferable that the etching solution composition contains at least one selected from hydrofluoric acid, a fluoride salt, or a metal hydroxide. Such an etching solution composition has low viscosity and is easy to control the liquid flow, thereby achieving relatively uniform etching. In particular, from the viewpoint of suppressing the formation of precipitates, the etching solution composition more preferably contains a metal hydroxide, and even more preferably contains both a metal hydroxide and a chelating agent. The chelating agent is not limited as long as it is a compound that can capture metal ions derived from the metal hydroxide, but from the viewpoint of efficiently capturing metal ions, it preferably contains a hydroxycarboxylic acid and / or a salt thereof. The etching solution composition may further contain other components as necessary.

[0038] <Metal Hydroxide> The metal hydroxide is a hydroxide of a metal element and can be appropriately selected depending on the purpose without any particular limitation as long as it is basic, and suitable examples thereof include sodium hydroxide (NaOH), potassium hydroxide (KOH), etc. These may be used alone or in combination of two or more.

[0039] The content of the metal hydroxide in the etching solution composition is preferably 2 mol / L or more and 8 mol / L or less, more preferably 2 mol / L or more and 7 mol / L or less, and even more preferably 3 mol / L or more and 7 mol / L or less.

[0040] <Hydroxycarboxylic Acid and / or Salt Thereof> The hydroxycarboxylic acid and / or salt thereof is not particularly limited and can be appropriately selected depending on the purpose, as long as it is a compound having a hydroxyl group and a carboxyl group and / or a salt thereof, and examples thereof include sugar acids such as aldonic acid, uronic acid, and aldaric acid; hydroxyethylethylenediaminetriacetic acid (HEDTA), hydroxyethyliminodiacetic acid (HIDA), dihydroxyethylglycine (DHEG), citric acid, lactic acid, glycolic acid, hydroxybutyric acid, malic acid, tartaric acid, salicylic acid, vanillic acid, protocatechuic acid, gallic acid, mandelic acid, benzilic acid, ferulic acid, sinapic acid, serine, threonine, tyrosine; and salts thereof. These may be used alone or in combination of two or more.

[0041] Examples of the aldonic acid include glyceric acid, xylonic acid, gluconic acid, heptogluconic acid, lactobionic acid, and ascorbic acid. Examples of the salt include sodium salts and potassium salts. Among these, gluconic acid and sodium gluconate are preferred.

[0042] The content of the hydroxycarboxylic acid and / or salt thereof in the etching solution composition is preferably 0.5 mol / L or more and 1.5 mol / L or less, and more preferably 0.6 mol / L or more and 1.5 mol / L or less.

[0043] <Other Components> The other components can be appropriately selected depending on the purpose as long as the effects of the present embodiment are not impaired. Examples of the other components include complexing agents other than hydroxycarboxylic acids and / or salts thereof, such as phosphorus ligands, Lewis bases, oxidizing agents, reducing agents, inorganic salts, amine compounds, carboxylic acid compounds, aminocarboxylic acid compounds, polymeric dispersants, surfactants, organic solvents, rheology control agents, and thickeners.

[0044] The diameter of the via hole is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 1 μm or more and 500 μm or less, and more preferably 50 μm or more and 100 μm or less. When the diameter of the via hole is 1 μm or more and 500 μm or less, glass having a high etching rate and a good hole shape can be produced.

[0045] Here, the via hole diameter is the top hole diameter φ on the first surface 112, which is the laser irradiation side when modifying. １ , the bottom hole diameter φ in the second surface 114 ２ , and / or top hole diameter φ １ and bottom hole diameter φ ２ The average diameter of the vias may be the average of the diameters of any 10 or more vias.

[0046] When the via is a through via, the goodness of the hole shape of each via can be evaluated by the "straightness" which is the ratio of the "neck diameter" to the "average hole diameter" which is the average value of the top hole diameter and the bottom hole diameter. The straightness is preferably 0.3 or more, and more preferably 0.35 or more.

[0047] Specifically, the top hole diameter φ of the opening of the through via is measured using a digital microscope (for example, VHX-8000, manufactured by Keyence Corporation) for the glass after etching. １ , and bottom hole diameter φ ２ The measurement is performed using a particle analysis function, and the circle equivalent diameter is taken as the hole diameter. Next, the glass is cut, and the cross section including the plurality of through vias is observed, and the constriction diameter φ at the constriction portion 190 is measured. ｗ The distance between the two narrowest points of each through via is measured. The "straightness" can be calculated using the following formula: (Formula) Straightness = Neck diameter / Average hole diameter

[0048] Furthermore, in order to compare the hole shapes between batches, the "corrected straightness" based on the target hole diameter (target hole diameter) can be used as an index. The "corrected straightness" can be calculated using the following formula: (Formula) Corrected neck diameter = target hole diameter - average hole diameter + neck diameter Corrected straightness = corrected neck diameter ÷ target hole diameter

[0049] In addition, as an index of the reduction in the variation in via diameter, the top diameter φ of any 10 or more (preferably 50 or more) vias is １ The top pore diameter φ can be evaluated by the coefficient of variation of the top pore diameter φ, i.e., standard deviation / average value. １ The upper limit of the coefficient of variation is preferably 0.030 or less, more preferably 0.025 or less, and even more preferably 0.020 or less, from the viewpoint of being able to keep the electrical resistance value after wiring formation within a practical level range. The lower limit is preferably 0.001 or more, more preferably 0.003 or more, and even more preferably 0.005 or more, from the viewpoint of facilitating product quality control. The lower limit of the number of vias formed on a single glass substrate is preferably 100 holes or more, more preferably 500 holes or more, even more preferably 1,000 holes or more, and particularly preferably 3,000 holes or more. The upper limit of the number of vias formed is preferably 100,000,000 holes or less, more preferably 10,000,000 holes or less, and even more preferably 1,000,000 holes or less. By setting the upper and lower limits within the above ranges, the top hole diameter φ １ The coefficient of variation can be controlled by varying the temperature during etching. The lower limit of the area of ​​the glass substrate is 0.01 cm ２ More than 1 cm is preferable. ２ More preferably, 3 cm or more ２ The upper limit of the area of ​​the glass substrate is 1,0000 cm. ２ Preferably, 5,000 cm or less ２ By setting the upper and lower limits within the above range, the top hole diameter φ １ The coefficient of variation of can be controlled by varying the temperature during etching.

[0050] The etching rate, which is an index of etching, can be evaluated by the "planarization rate" which is the rate at which the glass thickness is reduced per etching time [μm / hour]. The planarization rate is preferably 4.0 [μm / hour] or more, and more preferably 4.5 [μm / hour] or more.

[0051] Specifically, the average thickness t of the glass before etching ０[μm], and the average thickness t of the glass after etching １ The thickness [μm] is measured and calculated using a plate thickness measuring device (for example, a multicolor laser coaxial displacement meter with a CL-L015 (manufactured by Keyence Corporation) as the sensor head), and the "flat rate" can be calculated by dividing the thickness reduction by the etching time T [hours] using the following formula. (Formula) Flat rate [μm / hour] = (t ０ -t １ ) / T

[0052] Second Embodiment A method for manufacturing glass according to a second embodiment will be described below with reference to FIGS. 4 and 5. FIGS. 4 and 5 are schematic diagrams showing the flow of the method for manufacturing glass according to the second embodiment, illustrating aspects of the method for manufacturing glass having non-through vias. With the exception of forming non-through vias, the items described in the first embodiment can be selected as appropriate. The method for manufacturing glass according to the second embodiment includes, for example, steps S201 and S202. In step S201, a laser is irradiated onto a position on the glass substrate where a via is to be formed, to form a modified portion. In step S202, the glass having the modified portion is etched to form the plurality of vias.

[0053] In step S201, a laser is irradiated onto a position where a via is to be formed from the first surface 212 of the glass substrate 210 to form a modified portion 230. The glass substrate 210 has a first surface 212 and a second surface 214 opposite to the first surface 212. The glass substrate 210 can be appropriately selected from the glass substrate 110 and the glass described in the etching method of this embodiment.

[0054] 4 is a schematic cross-sectional view of the glass substrate 210 having the modified portion 230 after laser irradiation. When manufacturing glass having a non-penetrating via, a predetermined depth d １ A modified portion 230 of a non-penetrating via that communicates with the first surface 212 is formed. In the modified portion 230, an opening in the first surface 212 is referred to as a first initial opening 232.

[0055] Next, in step S202, the glass substrate 210 having the modified portion 230 is etched using the etching solution composition to a depth d ２At this time, the first initial opening 232 is expanded to form the first opening 252. Note that during the etching process, the surface of the glass substrate 210 is also etched, and the thickness of the glass substrate 210 is reduced to t ０ From t １ 5 shows a schematic cross-sectional view of glass with blind vias 250 after etching.

[0056] In this way, glass having non-penetrating vias 250 can be manufactured as shown in FIG.

[0057] Top diameter of via φ １ The via diameter is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 1 μm to 500 μm, and more preferably 50 μm to 100 μm. When the via hole diameter is 1 μm to 500 μm, glass can be produced that has a high etching rate and a good hole shape.

[0058] The depth of the non-penetrating via 250 is d ２ [μm], the aspect ratio d ２ / φ １ For example, it may be 1 or more.

[0059] The etching rate, which is an index of etching, can be evaluated by the planarization rate when the via is a non-through via, similarly to when the via is a through via. The planarization rate is preferably 4.0 [μm / hour] or more, and more preferably 4.5 [μm / hour] or more.

[0060] When the vias are non-penetrating vias, the top hole diameter φ is an index of whether the hole shape of each via is good. １ Via depth d ２ Half of (d ２ / 2) central hole diameter φ ｍ The ratio (φ ｍ / φ １ The ratio is preferably 0.3 or more, and more preferably 0.35 or more.

[0061] Furthermore, in order to compare the hole shapes between batches, the "corrected straightness" based on the target hole diameter (target hole diameter) can be used as an index. The "corrected straightness" can be calculated using the following formula: (Formula) Corrected median hole diameter = target hole diameter - average hole diameter + median hole diameter Corrected straightness = corrected median hole diameter ÷ target hole diameter

[0062] (Glass) The glass of the present embodiment is glass having a plurality of vias, wherein the number of vias per glass substrate is 100 to 100,000,000, the average hole diameter of the vias on one surface of the glass substrate is 1 μm to 500 μm, and the coefficient of variation of the hole diameters of the vias on one surface of the glass substrate is 0.001 to 0.03. The glass can be suitably produced by the glass production method of the present embodiment.

[0063] The via may be a through via that penetrates from one surface of the glass to the other surface, or a non-through via that has an opening on one surface of the glass and no opening on the other surface, and either can be selected appropriately depending on the purpose.

[0064] The number of vias per glass substrate is 100 or more and 100,000,000 or less, with the lower limit being more preferably 500 holes or more, still more preferably 1,000 holes or more, and particularly preferably 3,000 holes or more, and the upper limit being preferably 10,000,000 holes or less, more preferably 1,000,000 holes or less.

[0065] The average diameter of the vias on one surface of the glass substrate is 1 μm or more and 500 μm or less, and preferably 50 μm or more and 100 μm or less.

[0066] The coefficient of variation of the via hole diameter on one surface of the glass substrate is 0.001 or more and 0.030 or less. The lower limit of the coefficient of variation is preferably 0.003 or more, more preferably 0.005 or more, from the viewpoint of facilitating quality control of the product, and the upper limit is preferably 0.025 or less, more preferably 0.020 or less, from the viewpoint of being able to keep the electrical resistance value after wiring formation within a practical level range.

[0067] The average pore size and the coefficient of variation can be calculated by measuring the pore sizes at any 10 or more points (preferably 50 or more points) on one surface of the glass substrate and determining the average value and the coefficient of variation. The pore size is preferably the top pore size on the laser irradiation side during the glass manufacturing process.

[0068] When the vias are through vias, the straightness can be used to evaluate whether the hole shape of each via is good. The straightness is preferably 0.3 or more, more preferably 0.35 or more. When the vias are non-through vias, the top hole diameter φ １ Via depth d ２ Half of (d ２ / 2) central hole diameter φ ｍ The ratio (φ ｍ / φ １ The ratio is preferably 0.3 or more, and more preferably 0.35 or more.

[0069] The average diameter (φ) of the vias on one surface １ａｖｅ ) and the average diameter of the vias on the other surface (φ ２ａｖｅ ) to the average pore diameter ((φ １ａｖｅ -φ ２ａｖｅ ) ÷ ((φ １ａｖｅ +φ ２ａｖｅ ) / 2)) is preferably −0.3 or more and 0.3 or less, more preferably −0.2 or more and 0.2 or less, and even more preferably −0.1 or more and 0.1 or less, from the viewpoint of reducing the electrical resistance value after metallization.

[0070] The glass substrate may have holes of different diameters intentionally formed thereon depending on the purpose of wiring design, etc. For example, the glass substrate may have holes of any diameter and number, such as 1,000 holes with a target diameter of 100 μm, 500 holes with a target diameter of 80 μm, and 5 holes with a target diameter of 5,000 μm. In this case, the shapes of multiple holes having substantially the same diameter are compared and evaluated. This is because calculating the coefficient of variation of hole diameter for multiple holes with substantially different diameters results in a large value, resulting in inconsistent evaluation results.

[0071] The experimental data will be explained below. Examples 1 to 3 below are working examples, and Example 4 below is a comparative example.

[0072] (Example 1) <Formation of modified portions> An aluminosilicate-based alkali-free glass (EN-A1; manufactured by AGC Inc., size: 12 mm x 25 mm) with an average thickness of 1.1 mm was used as the glass substrate. A laser was irradiated at the planned via formation positions for forming through vias penetrating from one surface of the glass substrate to the other surface, to form modified portions. A green picosecond laser (wavelength 532 nm, pulse width 10 ps, ​​pulse energy 100 μJ) was used as the laser, and one shot was irradiated per planned formation position. The pitch between adjacent modified portions was 300 μm, and 3,200 modified portions were arranged in a 40 x 80 grid.

[0073] <Etching and Temperature Fluctuation> An etching solution composition was prepared by adding and mixing 3.00 mol / L NaOH and 0.15 mol / L sodium gluconate to water. 180 mL of the etching solution composition and a PTFE stirrer were placed in a 200 mL beaker, which was then set on a hot stirrer (RSH-6DN, manufactured by AS ONE Corporation) and heated to 90°C at a stirring speed of 300 rpm. A glass substrate on which a modified portion had been formed was immersed in the heated etching solution composition, and etching was carried out for 9 hours at a stirring speed of 300 rpm at 90°C ± 0.74°C, to produce the glass of Example 1 having a through via.

[0074] Two K-type thermocouples were used to measure the temperature of the etching solution composition. One of the thermocouples was connected to a hot stirrer and used for temperature control, and the other was connected to a data logger and the temperature was recorded at 1-minute intervals. The set temperature of the hot stirrer was manually changed to subject the etching solution composition to temperature fluctuations. As a result, the temperature fluctuation from 60 minutes after the start of etching to the end of etching was 90°C ± 0.74°C, and the coefficient of variation was 0.0083. Temperature control was performed using the values ​​displayed on the data logger, and the set temperature of the hot stirrer was adjusted based on the value of the data logger.

[0075] <Evaluation> The hole diameter was measured and the hole diameter variation (coefficient of variation of top hole diameter) and hole shape (corrected straightness) were evaluated according to the following procedure. The results are shown in Table 1.

[0076] <<Measurement of hole diameter and hole diameter variation>> For the glass after etching, a digital microscope (VHX-8000, manufactured by Keyence Corporation) was used to measure the top hole diameter φ of the opening of the through vias at 70 random points. １ and bottom hole diameter φ ２ , was measured. By measuring at least 50 points, it is possible to accurately evaluate the variation. The particle analysis function was used for the measurement, and the circle equivalent diameter was taken as the hole diameter. Top hole diameter φ １ and bottom hole diameter φ ２ The average value of the above was calculated as the "average pore diameter." The pore diameter variation was evaluated based on the coefficient of variation of the top pore diameter and the following evaluation criteria. A grade of B or higher is a practical level. -Evaluation criteria- A: The coefficient of variation of the top pore diameter is 0.020 or less. B: The coefficient of variation of the top pore diameter is more than 0.020 and 0.030 or less. C: The coefficient of variation of the top pore diameter is more than 0.030.

[0077] <<Hole Shape (Corrected Straightness)>> Next, the glass was cut, and a cross section including three arbitrary through vias was observed using a digital microscope. ｗ The distance between the two points at the narrowest part of each through via was measured. In order to compare the hole shapes between batches, the "corrected straightness" was calculated using the following formula. The target hole diameter in the formula was set to 50 μm. The hole shapes were evaluated based on the following evaluation criteria. A is the practical level. (Formula) Corrected neck diameter = target hole diameter - average hole diameter + neck diameter Corrected straightness = corrected neck diameter ÷ target hole diameter - Evaluation criteria - A: The corrected straightness is 0.24 or more B: The corrected straightness is less than 0.24

[0078] (Examples 2 to 4) Glasses of Examples 2 to 4 were produced in the same manner as in Example 1, except that the temperature fluctuation applied to the etching solution composition in Example 1 was changed as shown in the standard deviation [°C] of the etching conditions in Table 1. Then, evaluations were carried out in the same manner as in Example 1. The results are shown in Table 1.

[0079] 6 is a graph plotting the coefficient of variation of the top hole diameter against the coefficient of variation of the etching temperature in Examples 1 to 4. The approximate curves for these four points are shown by dashed lines. The coefficient of variation of the top hole diameter of 0.03 is shown by a dashed-dotted line. The coefficients of variation of the etching temperature of 0.001 and 0.025 are shown by dashed-dotted lines.

[0080]

[0081] The results in Table 1 and Figure 1 show that the variation in hole diameter increases when the temperature fluctuation during etching is too large or too small. Specifically, as in Example 4, when the etching temperature fluctuation is too large, the hole diameter varies and the hole shape is not good. On the other hand, as in Examples 1 to 3, when the coefficient of variation of the etching temperature profile is within a specific range, the coefficient of variation of the hole diameter improves. Furthermore, the approximation curve in Figure 1 shows that even when the etching temperature is constant (with small fluctuations), it leads to quality deterioration. From the above, it was found that when the coefficient of variation of the etching temperature is 0.001 or more and 0.025 or less after 60 minutes have passed since the start of etching, the hole shape is good and the variation in hole diameter can be reduced.

[0082] It can be seen that temperature fluctuations during etching have both positive and negative effects. The positive effect is the reduction of hole diameter variation. This is due to the fact that temperature fluctuations cause liquid flow and material diffusion inside and outside the via, which suppresses the generation of precipitates within the via and eliminates clogging with precipitates. The negative effect is the increase of hole diameter variation. This is due to the fact that when the temperature fluctuates above 100°C, the etching rate increases and dissolved material is rapidly generated, while when the temperature fluctuates below 100°C, nuclei are formed, promoting the generation of precipitates.

[0083] In other words, if the temperature fluctuation is too large, the negative effect becomes dominant, and conversely, if the temperature fluctuation is too small, the positive effect cannot be obtained. As a result, if the temperature fluctuation is too large or too small, the variation in pore size increases, and is approximated by a downward convex curve as shown in Figure 6. By controlling the temperature fluctuation within the range of the present invention, the positive and negative effects can be balanced and the variation in pore size can be reduced.

[0084] The glass manufacturing method according to the present disclosure has been described above, but the present disclosure is not limited to the above-described embodiments. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope of the claims. These changes also naturally fall within the technical scope of the present disclosure.

[0085] The following supplementary notes are disclosed regarding the above-described embodiments. [Supplementary Note 1] A method for manufacturing glass having a plurality of vias, comprising: etching glass having a modified portion to form the plurality of vias; and a coefficient of variation of the etching temperature after 60 minutes has elapsed since the start of etching is 0.001 or more and 0.025 or less. [Supplementary Note 2] In the glass, Li ２ O, Na ２ O and K ２ A method for producing glass according to Appendix 1, wherein the total content of O is 0 mol% to 10 mol%, and the total content of MgO, CaO, SrO, and BaO is 0 mol% to 30 mol%. [Appendix 3] A method for producing glass according to Appendix 1 or 2, wherein the average pore size of the vias is 1 μm or more and 500 μm or less. [Appendix 4] A method for producing glass according to any of Appendices 1 to 3, wherein the etching time is 2 hours or more and 240 hours or less. [Appendix 5] A glass having a plurality of vias, wherein the number of vias per glass is 100 or more and 100,000,000 or less, the average pore size of the vias on one surface of the glass is 1 μm or more and 500 μm or less, and a coefficient of variation of the pore sizes of the vias on one surface of the glass is 0.001 or more and 0.03 or less.

[0086] This application claims priority based on Japanese Patent Application No. 2024-110502, filed on July 9, 2024, the disclosure of which is incorporated herein in its entirety by reference.

[0087] 110 Glass substrate 112 First surface 114 Second surface 120 Modified portion 122 First initial opening 124 Second initial opening 140 Through via 142 First opening 144 Second opening 190 Narrowed portion 210 Glass substrate 212 First surface 214 Second surface 230 Modified portion 232 First initial opening 250 Non-through via 252 First opening

Claims

1. A method for manufacturing glass having a plurality of vias, comprising a step of etching glass having modified portions to form the plurality of vias, wherein the coefficient of variation of the etching temperature after 60 minutes has elapsed since the start of etching is 0.001 or more and 0.025 or less.

2. In the glass, Li ２ O, Na ２ O and K ２ 2. The method for producing glass according to claim 1, wherein the total content of O is 0 mol % to 10 mol %, and the total content of MgO, CaO, SrO, and BaO is 0 mol % to 30 mol %.

3. The method for manufacturing glass according to claim 1, wherein the average diameter of the vias is 1 μm or more and 500 μm or less.

4. The method for producing glass according to claim 1, wherein the etching time is from 2 hours to 240 hours.

5. Glass having a plurality of vias, wherein the number of vias per glass is 100 or more and 100,000,000 or less, the average pore size of the vias on one surface of the glass is 1 μm or more and 500 μm or less, and the coefficient of variation of the pore size of the vias on one surface of the glass is 0.001 or more and 0.03 or less.

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