Method for manufacturing a glass plate having a hole and a glass plate

Abstract

To provide a production method of a glass plate with a hole having a shape close to a desired one.SOLUTION: A production method has steps for: preparing a glass base material having first and second surfaces; forming an initial hole having a first initial opening on the first surface by irradiating the first surface of the glass base material with laser, the initial hole being an initial through hole or an initial non-through hole, the first initial opening having a maximum dimension φ1S (μm) of 5 μm or more, and in relation to each initial hole, when depth of the initial hole is set to be d1 (μm), an aspect ratio of the initial hole (d1 / φ1S) being 15 or more; and forming a treated hole from the initial hole by subjecting the glass base material to etching treatment with an alkali solution, wherein each treated hole has a first opening on the first surface, each first opening having a diameter φ1 (μm) and a circularity P1 (μm), and a ratio P1 / φ1 at each through hole being 10% or less.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a method for producing a glass sheet having a hole, and to a glass sheet. [Background technology]

[0002] Glass sheets having holes, such as through holes, are needed for many applications, such as glass interposers.

[0003] Such a glass plate is produced, for example, by irradiating one surface of a glass substrate with a laser to form holes, and then subjecting the glass substrate to a wet etching treatment to adjust the shape of the holes. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2006-176355 A [Patent Document 2] Special Publication No. 2018-531205 [Patent Document 3] International Publication No. 2020 / 149040 Summary of the Invention [Problem to be solved by the invention]

[0005] Generally, a hydrofluoric acid solution is used in the wet etching process of the glass substrate.

[0006] However, when a hole etching process is performed using a hydrofluoric acid solution, it is known that the shape of the hole often deviates from the desired shape, making it difficult to form holes of the desired shape with high precision.

[0007] Patent Documents 1 to 3 propose wet etching of a glass substrate using an alkaline solution.

[0008] In these documents, a modified portion is formed by first irradiating a glass substrate with a laser, and then an etching process is performed on the glass substrate with an alkaline solution to form holes in the modified portion.

[0009] However, the inventors of the present application have found through their experience that when holes are formed in this manner, the shape of the opening of the hole deviates from the desired shape, and an opening that is close to a perfect circle cannot be obtained.

[0010] Therefore, even if the methods described in Patent Documents 1 to 3 are adopted, it is difficult to form holes that are controlled with high precision.

[0011] The present invention has been made in view of the above background, and an object of the present invention is to provide a method for manufacturing a glass sheet having a hole with a shape closer to a desired shape. Another object of the present invention is to provide a glass sheet having a hole with a shape closer to a desired shape. [Means for solving the problem]

[0012] The present invention provides a method for producing a glass plate having a hole, comprising the steps of: (1) a step of irradiating a laser onto a first surface of a glass substrate having a first surface and a second surface opposed to each other, to form one or more initial holes having a first initial opening in the first surface, the initial pores are initial through pores or initial non-through pores, The first initial opening has a maximum dimension φ 1S (μm) is 5 μm or more, For each initial hole, the depth of the initial hole is d 1 (μm), the aspect ratio of the initial hole (d 1 / φ 1S ) is 15 or more; (2) etching the glass substrate with an alkaline solution to form treated holes from the initial holes; having Each treatment hole has a first opening in the first surface; Each first aperture has a diameter φ defined as the average of the diameter of the circumscribing circle and the diameter of the inscribing circle of the first aperture. 1 (μm) and roundness P 1 (μm), and the ratio P 1 / φ 1 is 10% or less.

[0013] In the present invention, A glass plate having a first surface and a second surface opposed to each other, and having a plurality of through holes extending from the first surface to the second surface, Each through hole has a first opening on the first surface and a second opening on the second surface, the larger of the first opening and the second opening being referred to as a specific opening; Each specific aperture has a diameter φ calculated as the average of the diameters of the circumscribing circle and the inscribing circle of the specific aperture. T (μm) and roundness P T (μm), and the ratio P T / φ T is 10% or less, The diameter φ of the specific opening in each through hole T The average value of φ Tave (μm), and the diameter φ T When the standard deviation is σ (μm), 3σ / φ Tave is less than or equal to 0.1, Five through holes randomly selected from the through holes are called selected through holes, and the minimum dimension of each narrowed portion in the cross section of the selected through holes is φ N (μm), for each selected through hole, φ N / φ T is greater than or equal to 0.5. Effect of the Invention

[0014] The present invention can provide a method for producing a glass plate having a hole with a shape closer to a desired shape. Also, the present invention can provide a glass plate having a hole with a shape closer to a desired shape. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a diagram showing a schematic cross-sectional shape of a through hole formed in a glass substrate by a conventional method. [Diagram 2] FIG. 1 is a diagram showing a schematic cross-sectional shape of a non-through hole formed in a glass substrate by a conventional method. [Diagram 3] FIG. 1 is a flow diagram illustrating an example of a method for producing a glass plate according to an embodiment of the present invention. [Figure 4] FIG. 2 is a diagram illustrating a schematic diagram of a step of a method for producing a glass plate according to an embodiment of the present invention. [Diagram 5] FIG. 2 is a diagram illustrating a schematic diagram of a step of a method for producing a glass plate according to an embodiment of the present invention. [Figure 6] FIG. 2 is a diagram illustrating a schematic diagram of a step of a method for producing a glass plate according to an embodiment of the present invention. [Figure 7] FIG. 4 is a flow chart illustrating an example of a method for producing a glass plate according to another embodiment of the present invention. [Figure 8] FIG. 4 is a diagram illustrating a schematic diagram of a step of a method for producing a glass plate according to another embodiment of the present invention. [Figure 9] FIG. 4 is a diagram illustrating a schematic diagram of a step of a method for producing a glass plate according to another embodiment of the present invention. [Figure 10] FIG. 1 is a diagram illustrating one embodiment of a cross section of a glass plate according to one embodiment of the present invention. [Figure 11] FIG. 2 is a diagram showing an example of a cross-sectional photograph of an initial through hole according to one embodiment of the present invention (Example 1). [Figure 12] FIG. 2 is a diagram showing an example of a microscope photograph of a through-hole after etching treatment according to one embodiment of the present invention (Example 1). [Figure 13] FIG. 13 is a diagram showing an example of a cross-sectional photograph of an initial through hole according to one embodiment of the present invention (Example 2). [Figure 14] FIG. 13 is a diagram showing an example of a microscope photograph of a through-hole after etching treatment according to one embodiment of the present invention (Example 2). [Figure 15]FIG. 13 is a diagram showing an example of a microscope photograph of a through-hole after etching treatment according to one embodiment of the present invention (Example 3). [Figure 16] FIG. 13 is a diagram showing an example of a microscope photograph of a through hole after etching treatment in Comparative Example (Example 21). [Figure 17] FIG. 13 is a diagram showing an example of a microscope photograph of a through hole after etching treatment in Comparative Example (Example 22). [Figure 18] FIG. 13 is a diagram showing an example of a microscope photograph of a through hole after etching treatment in a comparative example (Example 23). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0017] In this application, the glass to be processed before the etching process is referred to as a "glass substrate", and the glass to be processed after the etching process is referred to as a "glass plate", and the two are distinguished from each other. According to this definition, the "glass substrate" means the glass to be processed that has no holes before the laser irradiation, and the glass to be processed in which the initial holes are formed by the laser irradiation. On the other hand, the "glass plate" means a "glass substrate" having holes that have been shaped by the etching process. However, these distinctions are made for convenience, and the "glass plate" after the etching process may be referred to as a "glass substrate" from the viewpoint of ease of reading the specification.

[0018] As described above, in the method of manufacturing a glass plate having holes, when wet etching with hydrofluoric acid is performed, a problem often occurs in that holes of a desired shape cannot be obtained.

[0019] Fig. 1 shows a schematic cross-sectional shape of a through hole formed by a conventional method, in which the dashed line indicates an ideal through hole profile.

[0020] 1, a through hole 20A formed in a glass plate 10 by a conventional method has a substantially hourglass-shaped cross-sectional shape. That is, the through hole 20A has a "narrowed portion" 30A therein, which has a smaller diameter than the profile 2A of an ideal through hole.

[0021] Moreover, Fig. 2 shows a schematic cross-sectional shape of a non-through hole formed by a conventional method, in which the dashed line indicates the profile of an ideal through hole.

[0022] 2, non-through hole 20B formed in glass plate 10 by a conventional method has a cross section of a substantially inverted triangle shape. That is, non-through hole 20B has a diameter at its deepest portion that is not sufficiently expanded compared to profile 2B of an ideal non-through hole, and has a pointed "apex" 30B.

[0023] Thus, it is often found that the shapes of the through holes 20A and non-through holes 20B after etching process deviate from the desired shapes.

[0024] The inventors of the present application consider that the reason why the through holes 20A and the non-through holes 20B are not formed in the desired shapes is that a hydrofluoric acid solution is used in the wet etching process.

[0025] That is, the etching rate of the hydrofluoric acid solution is relatively high for the glass substrate. Therefore, if residues (insoluble etching products) are formed in the hole during etching with the hydrofluoric acid solution, other parts are etched before the residues are removed from the hole. As a result, the residues locally hinder the progress of subsequent etching of the hole, and as a result, the narrowed portion 30A is formed in the case of the through hole 20A, and the apex 30B is formed in the case of the non-through hole 20B.

[0026] In particular, when the aspect ratio of the through holes 20A and the non-through holes 20B is high, such an effect is expected to be more significant.

[0027] Thus, with the conventional methods, it is difficult to form holes in a glass substrate that are controlled with high precision.

[0028] One possible solution to this problem is to reduce the concentration of hydrofluoric acid used in the etching process.

[0029] However, a low-concentration hydrofluoric acid solution has a problem in that the hydrofluoric acid is consumed rapidly and the etching function deteriorates in a relatively short time, so that such a method is not suitable for industrial production of glass sheets with holes.

[0030] Moreover, Patent Documents 1 to 3 disclose a method of etching the laser modified portion using an alkaline solution.

[0031] However, the inventors of the present application have found that the methods described in Patent Documents 1-3 result in the shape of the opening of the hole that is finally formed deviating from the desired dimensions, and an opening that is close to a perfect circle cannot be obtained. Therefore, even when the methods described in Patent Documents 1-3 are adopted, it is difficult to form holes that are controlled with high precision.

[0032] In the methods described in Patent Documents 1 to 3, the reason why an opening of a desired shape cannot be obtained after etching is considered to be as follows.

[0033] In Patent Documents 1 to 3, first, a laser-modified portion extending in the depth direction is formed by irradiating a glass substrate with a laser. Next, the glass substrate having the modified portion is etched to selectively etch the laser-modified portion and form a hole.

[0034] Here, in order to form a hole of the desired diameter using the laser-modified area as a starting point, it is necessary to selectively remove the laser-modified area that has come into contact with the etching solution (initially, only the surface of the glass substrate) and "expand" the removed area in the stretching and radial directions.

[0035] However, such "expansion" does not necessarily result in isotropic removal of the glass substrate, particularly in the radial direction of the hole, and therefore such methods may result in the final hole having an opening that is not perfectly round.

[0036] In contrast, one embodiment of the present invention relates to a method for manufacturing a glass plate having a hole, comprising the steps of: (1) a step of irradiating a laser onto a first surface of a glass substrate having a first surface and a second surface opposed to each other, to form one or more initial holes having a first initial opening in the first surface, the initial pores are initial through pores or initial non-through pores, The first initial opening has a maximum dimension φ 1S (μm) is 5 μm or more, For each initial hole, the depth of the initial hole is d 1 (μm), the aspect ratio of the initial hole (d 1 / φ 1S ) is 15 or more; (2) etching the glass substrate with an alkaline solution to form treated holes from the initial holes; having Each treatment hole has a first opening in the first surface; Each first aperture has a diameter φ defined as the average of the diameter of the circumscribing circle and the diameter of the inscribing circle of the first aperture. 1 (μm) and roundness P 1 (μm), and the ratio P 1 / φ 1 is 10% or less.

[0037] In one embodiment of the present invention, an alkaline solution is used during the hole etching process.

[0038] The etching rate of the alkaline solution is lower than that of the hydrofluoric acid solution, but by performing the etching process of the holes at such a low etching rate, it is possible to reduce the amount of residue generated per unit time and provide sufficient time for the residue to dissipate from the holes to the outside.

[0039] Therefore, in one embodiment of the present invention, even when the aspect ratio of the hole is high, the problem of the etching process being hindered by the residue can be significantly suppressed, and as a result, a hole having a shape closer to the desired shape can be formed after the etching process.

[0040] In one embodiment of the present invention, a hole having an opening is formed in the glass substrate by laser irradiation, and the hole etching process is started using this hole as the starting shape.

[0041] In this case, unlike the case where the etching process is started with the modified portion as the starting shape, the etching can be performed by using a hole that already has an opening. Therefore, after the etching solution is filled in the hole, the hole can be etched more isotropically along the radial direction. As a result, a hole having an opening and a depth profile closer to the desired shape can be obtained.

[0042] Due to the above-mentioned effects, the method according to the embodiment of the present invention can provide a glass sheet having holes, including apertures, that are closer to the desired shape. In particular, the method according to the embodiment of the present invention can provide a profile that is closer to the desired shape even for holes with a high aspect ratio.

[0043] In the present application, the aspect ratio is usually defined as (depth of hole) / (diameter of opening on the surface on the laser irradiation side).

[0044] However, if the aperture is not a perfect circle, the maximum dimension of the aperture may be used instead of the aperture diameter.

[0045] (Method of manufacturing a glass sheet according to one embodiment of the present invention) Next, the method for producing a glass plate according to one embodiment of the present invention will be described more specifically with reference to FIGS.

[0046] FIG. 3 is a schematic diagram showing an example of a flow of a method for producing a glass plate according to an embodiment of the present invention.

[0047] As shown in FIG. 3, the method for producing a glass plate according to one embodiment of the present invention (hereinafter referred to as the "first method") includes the following steps: (1) preparing a glass substrate having a first surface and a second surface opposed to each other (S110); (2) A step (S120) of irradiating a first surface of the glass substrate with a laser to form one or more initial through holes penetrating from the first surface to the second surface; (3) wet etching the glass substrate with an alkaline solution (S130); has.

[0048] Each step will be described below.

[0049] (Step S110) First, a glass substrate is prepared.

[0050] 4 shows a schematic cross section of a glass substrate 110. The glass substrate 110 has a first surface 112 and a second surface 114 that face each other.

[0051] The composition of the glass substrate 110 is not particularly limited as long as it is glass. However, in the case of quartz glass, even if an etching process is performed using a hydrofluoric acid solution, little residue is left. Therefore, there is not much need to use the first method with quartz glass.

[0052] The glass substrate 110 may be, for example, soda-lime glass, calcium-free glass, or crystallized glass.

[0053] The dimensions of the glass substrate 110 are not particularly limited. However, the effect of the embodiment of the present invention can be more effectively achieved with a relatively thick glass substrate 110. 0 ) may be, for example, 0.1 mm or more.

[0054] (Process S120) Next, a laser is irradiated onto the first surface 112 of the glass substrate 110 to form an initial through hole.

[0055] The type of laser is not particularly limited as long as an initial through hole is formed in the glass substrate 110. The laser may be, for example, a UV laser.

[0056] Although there are no particular limitations on the laser irradiation conditions, the laser used is preferably a pulsed laser such as a femtosecond laser or a nanosecond laser, in which case a large number of initial through holes can be formed by a single scan.

[0057] FIG. 5 shows a schematic cross section of the glass substrate 110 after laser irradiation.

[0058] As shown in Fig. 5, a plurality of initial through holes 120 penetrating from the first surface 112 to the second surface 114 are formed in the glass substrate 110 by laser irradiation. In the example shown in Fig. 5, the first surface 112 is the laser incident surface.

[0059] In each initial through hole 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. In addition, the maximum value of the dimension of the first initial opening 122 is φ 1S The maximum dimension of the second initial opening 124 is set to φ 2S Let us assume that.

[0060] In a typical case, the first initial opening 122 and the second initial opening 124 are substantially elliptical (including circular; the same applies below). Therefore, the maximum dimension φ of the first initial opening 122 is 1S and the maximum dimension φ of the second initial opening 1242S are likely to correspond to the major axis of an ellipse (or the diameter of a circle), respectively.

[0061] In addition, in normal cases, the maximum dimension φ 1S ≧Maximum dimension φ 2S That is, the initial through hole 120 often has a generally tapered shape in which the cross-sectional dimensions gradually decrease from the first initial opening 122 to the second initial opening .

[0062] The maximum dimension φ of the first initial opening 122 1S is in the range of 5 μm to 30 μm, for example. 2S is, for example, in the range of 1 μm to 10 μm.

[0063] Moreover, the aspect ratio of the initial through hole 120 is 15 or more.

[0064] Here, the aspect ratio of the initial through hole 120 is, as described above, (depth of the initial through hole 120) / (maximum dimension φ of the first initial opening 122) 1S Here, (depth of the initial through hole 120)=(thickness t of the glass substrate 110) 0 ).

[0065] However, the maximum dimension φ 1S , maximum dimension φ 2S , and the aspect ratio may vary depending on the dimensions of the through-hole that is ultimately formed.

[0066] (Step S130) Next, the glass substrate 110 having the initial through-holes 120 is subjected to a wet etching process.

[0067] In the first method, the wet etching process is carried out using an etching solution that contains an alkaline component.

[0068] The etching solution may contain, for example, NaOH and / or KOH as an alkaline component, and may further contain a chelating agent such as ethylenediaminetetraacetic acid (EDTA).

[0069] The content of the alkaline component is not particularly limited, but is in the range of 1M to 10M, for example.

[0070] The temperature for the etching process is not particularly limited, but is in the range of 50°C to 95°C, for example.

[0071] The etching rate of the etching solution used is, for example, 0.4 μm / min or less, and preferably 0.1 μm / min or less.

[0072] In the present application, the etching rate is calculated as (amount of reduction in thickness of the glass substrate before and after treatment) / (treatment time).

[0073] FIG. 6 shows a schematic cross section of a glass substrate 110 (which may also be called a glass plate) after the wet etching process.

[0074] As shown in FIG. 6, the initial through-hole 120 is etched by a wet etching process to form a processed through-hole 140.

[0075] During the etching process, the surface of the glass substrate 110 is also etched, and the thickness of the glass substrate 110 becomes t 0 to t. Thus, the first surface 112 and the second surface 114 of the glass substrate 110 each change to a new surface after the treatment.

[0076] However, in this application, to avoid complication of explanation, the mutually opposing surfaces of the glass substrate 110 after the etching process will simply be referred to as the "first surface 112" and the "second surface 114".

[0077] Each process through hole 140 has a first opening 142 on the first surface 112 and a second opening 144 on the second surface 114. The first opening 142 and the second opening 144 may have a generally elliptical shape.

[0078] Diameter φ of the first opening 142 1 The diameter φ of the second opening 144 is in the range of 20 μm to 100 μm, for example. 2 is, for example, in the range of 20 μm to 100 μm.

[0079] The diameter φ of each of the first openings 142 1 is calculated as the average of the circumscribing circle diameter and the inscribing circle diameter of each of the first openings 142. Similarly, the diameter φ of each of the second openings 144 is calculated as the average of the circumscribing circle diameter and the inscribing circle diameter of each of the first openings 142. 2 is calculated as the average of the circumscribing circle diameter and the inscribing circle diameter of each of the second openings 144.

[0080] In addition, the aspect ratio (t / φ) of the processed through hole 140 1 ) may, for example, be 1 or greater.

[0081] Here, in each of the processed through holes 140, the circularity of the first opening 142 is P 1 (μm). Circularity P 1 is calculated using the following formula (1): P 1 = (diameter of the circumscribing circle of the first opening - diameter of the inscribing circle of the first opening) / 2 (1) In addition, this roundness P 1 Using the above, the ratio P 1 / φ 1 This value represents the "closeness" of the shape of the first opening 142 to a perfect circle. 1 / φ 1 It can be said that the smaller the radius of curvature of the first opening 142 is, the closer it is to a perfect circle.

[0082] In the first method, the processed through-hole 140 formed has a ratio P 1 / φ 1That is, in the first method, the first opening 142 having a shape close to a perfect circle is obtained in the processed through hole 140.

[0083] ratio P 1 / φ 1 is, for example, 5% or less, and preferably 2% or less.

[0084] Each processed through hole 140 preferably has a profile with equal cross-sectional dimensions along the stretching direction (thickness direction of the glass substrate 110) or a profile with a monotonically decreasing cross-sectional dimension from the first opening 142 to the second opening 144.

[0085] However, in reality, as shown in Fig. 6, the processing through hole 140 often has some narrowing portion 190 inside. However, even in such a case, the narrowing portion 190 in each processing through hole 140 is suppressed within an allowable range.

[0086] By the above steps, a glass plate having one or more treated through holes 140 can be manufactured.

[0087] In the first method, in the resulting glass sheet, each processed through hole 140 has a shape that is close to the desired shape.

[0088] For example, in a glass plate manufactured by the first method, five randomly selected processed through holes 140 are called “selected through holes”, and the minimum dimension of each narrowed portion 190 in the cross section of the “selected through holes” is φ N (μm), for each selected through hole, φ N / φ 1 may be 0.5 or more. In particular, φ N / φ 1 is preferably 0.6 or more, and more preferably 0.7 or more.

[0089] In this way, in the first method, the narrowed portion 190 that may be formed inside the processed through hole 140 is significantly suppressed. Therefore, in the glass plate manufactured by the first method, the processed through hole 140 can be appropriately filled with the conductive material.

[0090] In addition, the shape of the first opening 142 of the processing through-hole 140 is closer to a perfect circle. Therefore, when each processing through-hole 140 is filled with a conductive material, the positional accuracy of the conductive portion on the first surface 112 of the glass plate can be significantly improved.

[0091] (Method of manufacturing a glass sheet according to another embodiment of the present invention) Next, a method for producing a glass plate according to another embodiment of the present invention will be described with reference to FIGS.

[0092] FIG. 7 is a schematic diagram showing an example of a flow of a method for producing a glass plate according to another embodiment of the present invention.

[0093] As shown in FIG. 7, a method for producing a glass plate according to another embodiment of the present invention (hereinafter referred to as the "second method") includes the following steps: (1) preparing a glass substrate having a first surface and a second surface opposed to each other (S210); (2) a step (S220) of irradiating a first surface of the glass substrate with a laser to form one or more initial non-penetrating holes; (3) wet etching the glass substrate with an alkaline solution (S230); has.

[0094] The second method is different from the first method described above in that the holes formed in step S220 are initial non-through holes. In other words, in the second method, step S210 is the same as step S110 in the first method. Therefore, steps S220 and after will be described here.

[0095] (Process S220) In the second method, a laser is irradiated onto a first surface of a glass substrate to form initial non-through holes. As the laser, the one described in the first method can be used.

[0096] FIG. 8 shows a schematic cross section of the glass substrate 210 after laser irradiation.

[0097] As shown in Fig. 8, the glass substrate 210 has a first surface 212 and a second surface 214 facing each other. Furthermore, the glass substrate 210 has a plurality of initial non-through holes 230 formed therein, each having a first initial opening 232 on the first surface 212. Note that in Fig. 8, the first surface 212 of the glass substrate 210 is the laser incident surface.

[0098] In each initial non-through hole 230, the maximum value of the dimension of the first initial opening 232 is φ 1S Let us assume that.

[0099] Typically, the first initial opening 232 is generally elliptical, and therefore the maximum dimension φ of the first initial opening 232 1S is often thought to correspond to the dimension of the major axis of an ellipse (or the diameter of a circle).

[0100] In addition, in general, the initial non-through hole 230 often has a generally tapered shape in which the cross-sectional dimension gradually decreases from the first initial opening 232 toward the extension direction.

[0101] The maximum dimension φ of the first initial opening 232 1S is, for example, in the range of 5 μm to 30 μm.

[0102] Moreover, the aspect ratio of the initial non-through holes 230 is equal to or greater than 15. Here, the aspect ratio of the initial non-through holes 230 is, as described above, calculated by multiplying the depth d 1 ) / (maximum dimension φ of the first initial opening 232 1S )

[0103] However, these values ​​are determined depending on the dimensions of the non-through holes that are ultimately formed.

[0104] (Step S230) Next, the glass substrate 210 having the initial blind holes 230 is subjected to a wet etching process.

[0105] In the second method, the etching conditions are the same as those in the first method. For example, the processing solution contains an alkaline component such as NaOH and / or KOH. The etching temperature may be in the range of, for example, 50°C to 95°C.

[0106] FIG. 9 shows a schematic cross section of a glass substrate 210 (which may also be called a glass plate) after the wet etching process.

[0107] As shown in FIG. 9, the initial non-through holes 230 are etched by a wet etching process to form processed non-through holes 250.

[0108] Each processing blind hole 250 has a first opening 252 on the side of the first surface 212. The first opening 252 may have a generally elliptical shape.

[0109] Diameter φ of the first opening 252 1 As described above, the diameter φ of the first opening 252 is in the range of 20 μm to 100 μm, for example. 1 is calculated as the average of the diameter of the circumscribing circle and the diameter of the inscribing circle of the first opening 252.

[0110] The depth of the non-through hole 250 is d 2 (μm), the aspect ratio, i.e., the ratio d 2 / φ 1 may be, for example, 1 or more.

[0111] Here, in each of the non-through holes 250, the circularity of the first opening 252 is P 1 (μm), the ratio P 1 / φ 1is 10% or less. That is, in the second method, the first opening 252 having a shape close to a perfect circle is obtained in the processed non-through hole 250.

[0112] ratio P 1 / φ 1 is, for example, 5% or less, and preferably 2% or less.

[0113] Each processed non-through hole 250 preferably has a profile with equal cross-sectional dimensions along the stretching direction (thickness direction of the glass substrate 210) or a profile with a monotonically decreasing cross-sectional dimension in the depth direction from the first opening 252.

[0114] By the above steps, a glass plate having treated non-through holes 250 can be manufactured.

[0115] In the second method, as in the first method, a glass plate having non-through processed holes 250 with an approximately desired shape can be produced.

[0116] (Glass plate according to one embodiment of the present invention) Next, a glass plate according to one embodiment of the present invention and its features will be described with reference to FIG.

[0117] FIG. 10 is a schematic diagram showing one form of a cross section of a glass plate according to one embodiment of the present invention.

[0118] The glass plate 300 according to an embodiment of the present invention may be made of glass other than quartz glass, such as soda-lime glass, calcium-free glass, or crystallized glass.

[0119] There are no particular limitations on the dimensions of the glass plate 300. The thickness of the glass plate 300 may be, for example, 0.1 mm or more.

[0120] The glass plate 300 has a first surface 312 and a second surface 314 opposed to each other. The glass plate 300 also has a plurality of through holes 340 penetrating from the first surface 312 to the second surface 314. That is, each of the through holes 340 has a first opening 342 on the first surface 312 side and a second opening 344 on the second surface 314 side.

[0121] The first opening 342 has a diameter φ 1 (μm), and the second opening 344 has a diameter φ 2 (μm).

[0122] As described above, the "diameter" of the opening of each through hole 340 is calculated as the average of the diameter of the circumscribing circle and the diameter of the inscribing circle.

[0123] 10, in a glass plate 300 according to an embodiment of the present invention, each through hole 340 may have an internal narrowed portion 390. However, in the glass plate 300, this narrowed portion 390 is restricted within a predetermined range, as described below.

[0124] Such a glass plate 300 can be manufactured, for example, by the first method described above.

[0125] Here, in each through hole 340, the larger of the first opening 342 and the second opening 344 is referred to as a "specific opening." Furthermore, the diameter of the "specific opening" is referred to as "φ T " is expressed as

[0126] In each through hole 340, an opening (e.g., first opening 342) on one surface (e.g., first surface 312) of the glass plate 300 is not always the "specific opening." That is, in some through holes 340, the first opening 342 may be the "specific opening," and in other through holes 340, the second opening 344 may be the "specific opening."

[0127] This is because, in the actual manufacturing process of a glass plate, it is often the case that the opening on one side is preferentially etched during the etching process of the initial through hole.

[0128] Also, in some through holes 340, there may be no substantial difference in dimensions between the first opening 342 and the second opening 344. In such cases, either the first surface 312 or the second surface 314 is considered to be a "specific opening."

[0129] However, for simplicity, it is assumed here that the first opening 342 is the specific opening in each of the through holes 340. It is also assumed that the first surface 312 of the glass plate 300 is the laser irradiated surface.

[0130] In the glass plate 300 according to an embodiment of the present invention, the circularity of a specific opening of each through hole 340, i.e., the first opening 342, is defined as P T (μm), the ratio P T / φ T is less than 10%.

[0131] As shown in the above formula (1), the circularity of a specific opening P T is calculated using the following formula (2): P T = (diameter of circumscribing circle of specific opening - diameter of inscribing circle of specific opening) / 2 (2) As mentioned above, the ratio P T / φ T represents the "closeness" of the shape of a particular aperture to a perfect circle. That is, the ratio P T / φ T The smaller the ratio P, the closer the specific aperture is to a perfect circle. T / φ T The glass plate 300 having an average of 10% or less has a specific opening that is closer to a perfect circle.

[0132] ratio P T / φ T is, for example, 5% or less, and preferably 2% or less.

[0133] In addition, in the glass plate 300, the diameter φ of the specific opening in each through hole 340 T The average value of φ Tave (μm), and the diameter φ T When the standard deviation is σ (μm), 3σ / φ Tave is less than or equal to 0.1.

[0134] This is because, in the glass plate 300, the diameter φ of the specific opening T Therefore, it can be said that in the glass plate 300, each of the through holes 340 has a specific opening that is closer to a desired shape.

[0135] Furthermore, in the glass plate 300, five through holes randomly selected from the through holes 340 are called “selected through holes”, and the minimum dimension of each narrowed portion 390 in the cross section of the “selected through holes” is φ N (μm), for each selected through hole, φ N / φ T In particular, φ is 0.5 or more. N / φ T is preferably 0.6 or more, and more preferably 0.7 or more.

[0136] In this way, in the glass plate 300, the narrowed portion 390 is significantly suppressed.

[0137] In the glass plate 300 having the above-mentioned characteristics, the through-holes 340 can be appropriately filled with a conductive material.

[0138] In addition, the through-holes 340 have a specific opening shape that is close to a perfect circle, and when each through-hole 340 is filled with a conductive material, the positional accuracy of the conductive portion on the first surface of the glass plate 300 can be significantly improved. EXAMPLES

[0139] Examples of the present invention will now be described below, with reference to Examples 1 to 3 which are examples, and Examples 21 to 23 which are comparative examples.

[0140] (Example 1) A glass plate having a large number of through holes was formed by the above-mentioned first method.

[0141] The glass substrate used was alkali-free glass (AN100; manufactured by AGC Corporation) having a thickness of 0.5 mm.

[0142] With an absorbent material attached to the first surface of the glass substrate, the first surface of the glass substrate was irradiated with a laser to form an initial through hole. A nanosecond pulsed UV laser was used as the laser. The laser was irradiated with 50 shots with a pulse energy of 20 μJ, and then irradiated with 1200 shots with a pulse energy of 40 μJ. The repetition frequency was 10 kHz, and after the initial through hole was formed, the absorbent material was removed.

[0143] In each initial through hole, the maximum dimension φ of the first initial opening formed on the first surface side of the glass substrate 1S The aspect ratio of each initial through hole was approximately 33.3.

[0144] An example of a cross-sectional photograph of the formed initial through hole is shown in Fig. 11. From Fig. 11, it can be seen that the initial through hole having a high aspect ratio was formed.

[0145] Next, the glass substrate was immersed in an etching solution to carry out an etching treatment.

[0146] The etching solution used was an aqueous solution containing 3 M NaOH and 1.5 M EDTA. The temperature of the etching solution was 85° C., and the immersion time was 744 minutes.

[0147] After the treatment, the glass substrate was removed from the etching solution and the thickness was measured. It was found that the glass substrate was thinner by 46 μm. Therefore, the etching rate during the applied etching treatment was 0.062 μm / min.

[0148] After the etching process, a glass plate having a number of through holes formed therein was formed, each through hole having a first opening on a first surface side of the glass plate and a second opening on a second surface side of the glass plate.

[0149] (evaluation) (Measurements for the first opening) The diameter (φ) of the opening (i.e., the first opening) of each through hole on the laser irradiation side of the obtained glass plate was measured using a shape measuring instrument (VMR-Z6555; manufactured by Nikon Corporation). 1 ), and circularity (P 1 ) was measured. From the results, the average (φ 1ave ), and (3σ / φ 1ave ) etc. were obtained. Furthermore, the ratio P 1 / φ 1 was calculated, and the average, minimum, and maximum values ​​were calculated.

[0150] As described above, the diameter φ of the first opening 1 was calculated as the average of the diameter of the circumscribed circle and the diameter of the inscribed circle. 1 was calculated from the above formula (1). Also, σ is the standard deviation.

[0151] Furthermore, the cross-sections of five selected through-holes (selected through-holes) in the glass plate were observed under an optical microscope to determine the minimum dimension (φ N ) and the average (φ Nave ) was obtained. In addition, the ratio φ N / φ 1 asked for.

[0152] The measurement results are summarized in the column for Example 1 in Table 1 below.

[0153] [Table 1] (Measurements for the second opening) For each through hole, the second opening was measured by the same method as described above (measurement for the first opening).

[0154] From the obtained results, the specific opening of each through hole was determined. In addition, various values ​​related to the specific opening were obtained. Specifically, the average diameter of the specific opening (φ Tave ), 3σ, (3σ / φ Tave ) and the ratio P T / φ T The average, minimum, and maximum values ​​were calculated.

[0155] Furthermore, in the above-mentioned five selective through holes, the ratio φ N / φ T asked for.

[0156] The measurement results are summarized in the column for Example 1 in Table 2 below.

[0157] [Table 2] FIG. 12 shows an example of a micrograph of a selective through-hole.

[0158] In FIG. 12, the top shows the first surface of the glass plate, the middle shows a cross section of the selected through-hole, and the bottom shows the shape of the second surface of the glass plate.

[0159] From FIG. 12, it can be seen that both the first and second openings are nearly perfectly circular. In fact, in the results shown in Table 2, P T / φ T The average was 3.0%, and the maximum value was also low at 6.2%.

[0160] In addition, it was found from FIG. 12 that the narrowed portions of the selective through-holes were not very significant. In fact, as shown in Table 2, (φN / φ T ) was over 59%, showing a large value.

[0161] Furthermore, as shown in Table 2, 3σ / φ Tave The diameter of the specific opening between each through hole was φ T It was found that the variation was small.

[0162] (Example 2) In the same manner as in Example 1, a glass plate having a large number of through holes was formed.

[0163] However, in Example 2, the glass substrate used was an alkali-free glass having a dielectric tangent of 0.005 or less at 10 GHz, which was different from that in Example 1. The immersion time in the etching solution was 166 minutes. The etching rate during the applied etching process was 0.343 μm / min.

[0164] The columns for Example 2 in Table 1 and Example 2 in Table 2 above show the results of measuring the dimensions of each of the through holes formed.

[0165] An example of a cross-sectional photograph of an initial through hole before etching is shown in Fig. 13. From Fig. 13, it can be seen that a through hole with a high aspect ratio was formed.

[0166] FIG. 14 shows an example of a micrograph of a selective through-hole.

[0167] In FIG. 14, the top shows the first surface of the glass plate, the middle shows a cross section of the selected through-hole, and the bottom shows the shape of the second surface of the glass plate.

[0168] From FIG. 14, it can be seen that both the first and second openings are nearly perfectly circular. In fact, in the results shown in Table 2, P T / φ T The average was 2.7%, and the maximum value was also low at 3.2%.

[0169] In addition, it was found from FIG. 14 that the narrowed portions of the selective through-holes were not very significant. In fact, as shown in Table 2, (φ N / φ T ) was over 62%, showing a large value.

[0170] Furthermore, as shown in Table 2, 3σ / φ Tave The diameter of the specific opening between each through hole was φ T It was found that the variation was small.

[0171] (Example 3) In the same manner as in Example 2, a glass plate having a large number of through holes was formed.

[0172] However, in this Example 3, the temperature of the etching solution was set to 65° C. The immersion time of the glass substrate in the etching solution was set to 540 minutes. The etching rate during the applied etching process was 0.083 μm / min.

[0173] The columns for Example 3 in Table 1 and Example 3 in Table 2 above show the results of measuring the dimensions of each of the through holes formed.

[0174] FIG. 15 shows an example of a micrograph of a selective through-hole.

[0175] In FIG. 15, the top shows the first surface of the glass plate, the middle shows a cross section of the selected through-hole, and the bottom shows the shape of the second surface of the glass plate.

[0176] From FIG. 15, it can be seen that both the first and second openings are nearly perfectly circular. In fact, in the results shown in Table 2, P T / φ T The average was 3.2%, and the maximum value was also low at 5.7%.

[0177] In addition, it was found from FIG. 15 that the narrowed portions of the selective through-holes were not very significant. In fact, as shown in Table 2, (φ N / φ T) was over 74%, showing a large value.

[0178] Furthermore, as shown in Table 2, 3σ / φ Tave The diameter of the specific opening between each through hole was φ T It was found that the variation was small.

[0179] (Example 21) In the same manner as in Example 1, a glass plate having a large number of through holes was formed.

[0180] However, in this Example 21, an aqueous solution containing 2.3 wt % hydrofluoric acid and 6 wt % nitric acid was used as the etching solution, and the temperature of the etching solution was set to 25°C.

[0181] The immersion time of the glass substrate in the etching solution was 111 minutes. The average etching during the applied etching process was 0.901 μm / min.

[0182] The columns for Example 21 in Table 1 and Example 21 in Table 2 above show the results of measuring the dimensions of each of the through holes formed.

[0183] FIG. 16 shows an example of a micrograph of a portion of a selective through-hole.

[0184] In FIG. 16, the top shows the first surface of the glass plate, the middle shows a cross section of the selected through-hole, and the bottom shows the shape of the second surface of the glass plate.

[0185] From FIG. 16, it was found that a significant narrowing occurred inside the selective through-hole. In fact, as shown in Table 2, (φ N / φ T ) was less than 35%, showing a small value.

[0186] Furthermore, as shown in Table 2, 3σ / φ Tave The diameter of the specific opening φ TIt was found that there was a large variability.

[0187] (Example 22) In the same manner as in Example 21, a glass plate having a large number of through holes was formed.

[0188] However, in this Example 22, ultrasonic vibration was applied to the solution during the etching process. The glass substrate was immersed in the etching solution for 94 minutes. The etching rate during the applied etching process was 1.043 μm / min.

[0189] The columns for Example 22 in Table 1 and Example 22 in Table 2 above show the results of measuring the dimensions of each of the through holes formed.

[0190] FIG. 17 shows an example of a micrograph of a portion of a selective through-hole.

[0191] In FIG. 17, the top shows the first surface of the glass plate, the middle shows a cross section of the selected through-hole, and the bottom shows the shape of the second surface of the glass plate.

[0192] From FIG. 17, it was found that in Example 22, the narrowed portions of the selected through-holes were not very noticeable.

[0193] However, as shown in Table 2, 3σ / φ Tave From this, it can be seen that in Example 22, the diameter φ of the specific opening between the formed through holes was T It was found that there was a large variability.

[0194] (Example 23) A glass plate having a large number of through holes was formed by the following method.

[0195] The glass substrate used was alkali-free glass (AN100; manufactured by AGC Corporation) having a thickness of 0.3 mm.

[0196] Next, a laser was irradiated from the first surface side of the glass substrate to form a modified part extending from the first surface to the second surface along the thickness direction. A picosecond pulse green laser was used as the laser. The laser irradiation power was 100 μJ, the repetition frequency was 200 kHz, and the processing was performed in one shot.

[0197] Next, the glass substrate was immersed in an etching solution to carry out an etching treatment.

[0198] The etching solution used was an aqueous solution containing 3 M NaOH and 1.5 M EDTA. The temperature of the etching solution was 85° C., and the immersion time was 588 minutes.

[0199] After the treatment, the glass substrate was taken out of the etching solution and the thickness was measured. It was found that the glass substrate was thinner by 0.04 μm. Therefore, the etching rate during the applied etching treatment was 0.068 μm / min.

[0200] After the etching process, a glass plate having a number of through holes formed therein was formed, each through hole having a first opening on a first surface side of the glass plate and a second opening on a second surface side of the glass plate.

[0201] Thereafter, the shape of each through hole was measured in the same manner as in Example 1.

[0202] The columns for Example 23 in Table 1 and Example 23 in Table 2 above show the results of measuring the dimensions of each of the through holes formed.

[0203] FIG. 18 shows an example of a micrograph of a portion of a selective through-hole.

[0204] In FIG. 18, the top shows the first surface of the glass plate, the middle shows a cross section of the selected through-hole, and the bottom shows the shape of the second surface of the glass plate.

[0205] From FIG. 18, it was found that in Example 23, the narrowed portions of the selected through-holes were not very noticeable.

[0206] However, it was found that the first opening and the second opening of the selective through hole were both elliptical in shape, which was significantly different from a perfect circle. T / φ T The average was 7.5%, with individual measurements showing high values ​​ranging from 5.0% to 13.7%.

[0207] Thus, in Example 23, it was found that the shapes of the first opening and the second opening in the formed through-hole were far from a perfect circle.

[0208] From the above results, it was confirmed that in Examples 1 to 3, it was possible to form through holes having shapes closer to the desired shapes than in Examples 21 to 23. [Explanation of symbols]

[0209] 2A Ideal Through Hole Profile 2B Ideal blind hole profile 10 Glass Plate 20A through hole 20B Non-through hole 30A Stenosis 30B Vertex 110 Glass substrate 112 First Surface 114 Second Surface 120 Initial through hole 122 First initial opening 124 Second Initial Opening 140 Processing Through Hole 142 First Opening 144 Second Opening 190 Stenosis 210 Glass substrate 212 First Surface 214 Second Surface 230 Initial non-through hole 232 First initial opening 250 Processing non-through hole 252 First Opening 300 Glass Plate 312 First Surface 314 Second Surface 340 Through hole 342 First Opening 344 Second Opening 390 Stenosis

Claims

1. A method for producing a glass sheet having a hole, comprising the steps of: (1) A step of irradiating a first surface of a glass substrate having a first surface and a second surface opposed to each other with a laser to form one or more initial holes having a first initial opening in the first surface, the initial pores are initial through pores or initial non-through pores, The first initial opening has a maximum dimension φ １Ｓ (μm) is 5 μm or more, For each initial hole, the depth of the initial hole is d １ (μm), the aspect ratio of the initial hole (d １ / φ １Ｓ ) is 15 or more; (2) etching the glass substrate with an alkaline solution to form treated holes from the initial holes; having Each treatment hole has a first opening in the first surface; Each first opening has a diameter φ defined as the average of the diameter of the circumscribing circle and the diameter of the inscribing circle of the first opening. １ (μm) and roundness P １ (μm), and the ratio P １ / φ １ is 10% or less.

2. 2. The method according to claim 1, wherein the etching rate in the step (2) is 0.4 μm / min or less.

3. The method according to claim 1 or 2, wherein the temperature of the alkaline solution in the step (2) is in the range of 50° C. to 95° C.

4. The method according to claim 1 , wherein the laser is a UV laser.

5. The method according to claim 1 , wherein the alkaline solution comprises KOH and / or NaOH.

6. The method according to claim 1 , wherein the glass substrate has a thickness of 0.1 mm or more.

7. The treatment hole is a through hole, Five through holes randomly selected from the through holes are called selected through holes, and the minimum dimension of each narrowed portion in the cross section of the selected through holes is φ Ｎ (μm), in each selected through hole, φ Ｎ / φ １ The method according to claim 1 , wherein is 0.5 or more.

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