JP2017190285A - Manufacturing method of glass substrate having open hole and method for forming open hole on glass substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a glass substrate having open holes with a relatively arranged shape.SOLUTION: There is provided a manufacturing method of a glass substrate having a process for forming an initial pore in a glass substrate by irradiating a laser light to the glass substrate, a process for conducting a first etching treatment on the initial pore and thereby forming a first open hole existing from a first opening to second opening and a ratio d/Ris in a range of 10 to 20, where dis thickness of the glass substrate and Ris diameter of the first opening of the first open hole, a process for conducting a second etching treatment on the first open hole, thereby forming a second open hole having a third opening on the first surface and having a fourth opening on the second surface and a second solution has etching rate larger than the first solution to the glass substrate.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a method for producing a glass substrate having a through hole and a method for forming a through hole in the glass substrate.

  Conventionally, a technique for forming one or more through holes in a glass substrate by irradiating the glass substrate with laser light generated from a laser light source is known (for example, Patent Document 1).

  A glass substrate having such a through hole is used for, for example, a glass interposer in which the through hole is filled with a conductive filler.

JP 2003-226551 A

Usually, a glass substrate having a through-hole as described above is
(1) preparing a glass substrate having first and second surfaces;
(2) By irradiating laser light from the first surface side of the glass substrate, the glass substrate penetrates from the first opening on the first surface of the glass substrate to the second opening on the second surface of the glass substrate. Forming a through hole;
(3) a step of expanding the through hole to a desired size by wet-etching the glass substrate;
It is manufactured through.

  Here, when the step (3) is performed, there is often a problem that a narrowed portion is generated at a substantially central portion of the through hole along the full length direction of the through hole.

  This is because the diameter of the through-hole formed in the step (2) is relatively smaller than the thickness of the glass substrate. That is, when such a “fine” through-hole is subjected to the wet etching process in the step (3), the concentration diffusion of the etching solution does not sufficiently proceed inside the through-hole, and the etching reaction The product of stagnation in the through hole. As a result, it becomes difficult to sufficiently advance the etching reaction inside the through hole, and a narrowed portion is generated.

  In particular, in the field of glass interposers, extremely fine through holes are formed in the step (2). For this reason, in the manufacturing process of a glass interposer, there exists a problem that such a narrow part will become easy to generate | occur | produce in a through-hole.

  An object of the present invention is to provide a method for producing a glass substrate having a through hole having a relatively uniform shape. Another object of the present invention is to provide a method of forming a through hole having a relatively uniform shape in a glass substrate. Another object of the present invention is to provide a glass substrate manufacturing system in which a through hole having a relatively uniform shape is formed in the glass substrate.

In the present invention, a method for producing a glass substrate having a through-hole,
(1) forming first holes in the glass substrate by irradiating laser light from the first surface side of the glass substrate having first and second surfaces facing each other;
(2) A first etching process is performed on the glass substrate using a first etching solution, and the second opening is formed from the first opening formed in the first surface from the initial hole. forming a first through hole extending to a second opening formed on the surface, when the thickness of the glass substrate and d _1, the diameter of the first opening and the R _t1, the ratio d ₁ / R _t1 is in the range of 10-20,
(3) After the step (2), a second etching solution is used for the glass substrate by using a second etching solution having an etching rate larger than that of the first etching solution. Performing a process to enlarge the first through hole;
A manufacturing method comprising:
Is provided.

Further, in the present invention, a method for forming a through hole in a glass substrate,
(1) forming first holes in the glass substrate by irradiating laser light from the first surface side of the glass substrate having first and second surfaces facing each other;
(2) A first etching process is performed on the glass substrate using a first etching solution, and the second opening is formed from the first opening formed in the first surface from the initial hole. forming a first through hole extending to a second opening formed on the surface, when the thickness of the glass substrate and d _1, the diameter of the first opening and the R _t1, the ratio d ₁ / R _t1 is in the range of 10-20,
(3) After the step (2), a second etching solution is used for the glass substrate by using a second etching solution having an etching rate larger than that of the first etching solution. Performing a process to enlarge the first through hole;
Is provided.

  The present invention can provide a method for producing a glass substrate having a through hole having a relatively uniform shape. Moreover, in this invention, the method of forming the through-hole which prepared the shape comparatively in the glass substrate can be provided. Moreover, in this invention, the manufacturing system of the glass substrate which forms the through-hole which prepared the shape comparatively in the glass substrate can be provided.

It is the flowchart which showed schematically the manufacturing method of the glass substrate which has the conventional through-hole. It is the figure which showed typically 1 process in the manufacturing method of the glass substrate which has the conventional through-hole shown in FIG. It is the figure which showed roughly an example of the flow of the manufacturing method of the glass substrate which has a through-hole by one Embodiment of this invention. It is the figure which showed typically 1 process in the manufacturing method of the glass substrate which has a through-hole by one Embodiment of this invention shown in FIG. It is the figure which showed typically 1 process in the manufacturing method of the glass substrate which has a through-hole by one Embodiment of this invention shown in FIG. It is the figure which showed typically 1 process in the manufacturing method of the glass substrate which has a through-hole by one Embodiment of this invention shown in FIG. It is the figure which showed typically 1 process in the manufacturing method of the glass substrate which has a through-hole by one Embodiment of this invention shown in FIG.

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

(Conventional method for producing a glass substrate having a through hole)
First, in order to better understand the characteristics of the present invention, a conventional method for manufacturing a glass substrate having a through hole will be briefly described with reference to FIGS.

  FIG. 1 schematically shows a flow of a conventional method for producing a glass substrate having a through hole (hereinafter simply referred to as “conventional production method”). FIG. 2 schematically shows one step in the conventional manufacturing method shown in FIG.

As shown in FIG. 1, the conventional manufacturing method is as follows.
A step of preparing a glass substrate (step S10);
Irradiating a glass substrate with laser light to form a through hole (step S20);
A step of wet-etching the glass substrate having a through hole to widen the through hole to a desired dimension (step S30);
Have

  Among these, in process S10, as shown to Fig.2 (a), the glass substrate 10 which has the 1st surface 12 and the 2nd surface 14 is prepared.

  Next, in step S20, the through hole 20 is formed in the glass substrate 10 as shown in FIG. The through hole 20 is formed by irradiating a laser beam (not shown) from the first surface 12 side of the glass substrate 10.

The through-hole 20 has a first opening 22 on the first surface 12 of the glass substrate 10 and a second opening 24 on the second surface 14. The diameter of the first opening 22 is φ _t0 , and the diameter of the second opening 24 is φ _b0 .

  Next, in step S30, the glass substrate 10 is subjected to a wet etching process in order to expand the diameter of the through hole 20 to a desired dimension.

Here, when the diameter φ _t0 of the first opening 22 (or the diameter φ _b0 of the second opening 24) of the through hole 20 formed in step S20 is sufficiently large, the etching solution is used during the wet etching process. Along the entire length of the through-hole 20, it can be supplied uniformly and sufficiently. For this reason, the through-hole 20 is etched relatively uniformly.

However, when the diameter φ _t0 of the first opening 22 and the diameter φ _b0 of the second opening 24 are reduced, the etching reaction sufficiently proceeds in the fine through-hole 20 during the wet etching process. It becomes difficult to let them. This is because the concentration diffusion of the etching solution does not sufficiently proceed inside the through hole 20, and the product of the etching reaction tends to stay in the through hole 20. Further, in such a fine through hole 20, it may be difficult to sufficiently supply the etching solution to the inside of the through hole 20 itself.

  Therefore, the first and second openings 22 and 24 and the vicinity thereof are selectively etched in the through hole 20. In other words, it becomes difficult to sufficiently etch the through hole 20 inside the through hole 20.

  As a result, after step S30, as shown in FIG. 2 (c), an extended through hole 30 having a cross-sectional shape of “hourglass” is formed. That is, the expanded through hole 30 to be formed has a predetermined dimension on the side of the first opening 32 and the second opening 34, but the narrowed portion 36 that does not satisfy the predetermined dimension is formed inside the through hole 30. To have.

As described above, in the conventional manufacturing method, in particular, when the diameter (φ _t0 , φ _b0 ) of the through hole 20 becomes relatively small with respect to the thickness of the glass substrate 10, the extended through hole 30 has a remarkable narrowed portion 36. There is a problem of becoming.

(Method of manufacturing a glass substrate having a through hole according to an embodiment of the present invention)
Next, with reference to FIGS. 3-7, an example of the manufacturing method of the glass substrate which has a through-hole by one Embodiment of this invention is demonstrated.

  In FIG. 3, an example of the flow of the manufacturing method of the glass substrate which has a through-hole by one Embodiment of this invention is shown roughly. 4 to 7 schematically show aspects of each step in the method for manufacturing a glass substrate having a through hole according to an embodiment of the present invention.

As shown in FIG. 3, a method for manufacturing a glass substrate having a through hole according to an embodiment of the present invention (hereinafter referred to as “first manufacturing method”)
(0) preparing a glass substrate having first and second surfaces facing each other (step S110);
(1) A step of forming initial holes in the glass substrate by irradiating laser light from the first surface side of the glass substrate (step S120);
(2) performing a first etching process on the initial hole using a first etching solution,
Thereby, a first through hole extending from the first opening to the second opening is formed in the glass substrate,
When the thickness of the glass substrate after the step (2) is d ₁ and the diameter of the first opening of the first through hole is R _t1 , the ratio d ₁ / R _t1 is 10 to 20 A step (step S130) that is in the range of
(3) a step of performing a second etching process on the first through hole using a second etching solution (step S140);
Have

  Hereinafter, each step will be described in detail with reference to FIGS.

(Step S110)
First, a glass substrate 110 having a cross-sectional shape as shown in FIG. 4 is prepared. The glass substrate 110 has a first surface 112 and a second surface 114 that face each other. The glass substrate 110 has an initial thickness _{d 0.}

For example, the initial thickness d ₀ is preferably 0.1 mm to 0.7 mm, more preferably 0.2 mm to 0.5 mm, and particularly preferably 0.3 mm to 0.5 mm. When the initial thickness d ₀ is less than 0.3 mm, the above-described hourglass-shaped extended through-holes may be difficult to be formed even in the conventional manufacturing method.

  The composition of the glass substrate 110 is not particularly limited. The glass substrate 110 may be, for example, soda lime glass and non-alkali glass.

(Step S120)
Next, one or more initial holes are formed in the glass substrate 110 by irradiating laser light from the first surface 112 side of the glass substrate 110.

As long as an initial hole can be formed in the glass substrate 110, the kind and irradiation conditions of the laser light are not limited. The laser light may be, for example, a CO ₂ laser, a UV laser, or the like. The laser beam may be a laser beam oscillated from a short pulse laser (for example, a picosecond laser or a femtosecond laser).

  The form of the initial hole is not particularly limited, and the initial hole may be a through hole or a non-through hole. Further, the initial holes may be a void row composed of a plurality of voids arranged along the thickness direction of the glass substrate 110. When a short pulse laser is used, a void row is easily formed as an initial hole.

  FIG. 5 shows a state where the initial holes 120 are formed in the glass substrate 110. In the example shown in FIG. 5, the initial hole 120 is a through hole, and is referred to as an “initial through hole” 120 here.

As shown in FIG. 5, the initial through-hole 120 is formed from the first initial opening 122 formed in the first surface 112 of the glass substrate 110, and the second through-hole 120 formed in the second surface 114 of the glass substrate 110. Extend to initial opening 124. In the initial through hole 120, the diameter of the first initial opening 122 is referred to as _Rt0, and the diameter of the second initial opening 124 is referred to as _Rb0 .

Here, the ratio of the thickness d ₀ of the glass substrate 110 and the diameter R _t0 of the first initial opening 122 at this stage, that is, d ₀ / R _t0 is, for example, 25 or more. The ratio d ₀ / R _t0 is preferably 30 or more. When the ratio d ₀ / R _t0 is 25 or more, a large effect can be obtained by changing the conventional manufacturing method to the first manufacturing method. That is, when the ratio d ₀ / R _t0 is 25 or more, in the conventional manufacturing method, a large constricted portion is generated in the through hole by the etching process. However, in the first manufacturing method, this stenosis can be significantly suppressed.

The diameter R _t0 of the first initial opening 122 is, for example, 15 μm or less, and may be 13 μm or less.

In the example shown in FIG. 5, for simplification, the diameter R _t0 of the first initial opening 122 of the initial through hole 120 and the diameter R _b0 of the second initial opening 124 are substantially equal. It is shown. However, the initial through-hole 120 formed by laser light irradiation may actually have a tapered shape in which the diameter gradually decreases from the first initial opening 122 toward the second initial opening 124. It should be noted that there are many. Therefore, usually R _t0 > R _b0 .

  Although only a single initial through hole 120 is shown in FIG. 5, a plurality of initial through holes 120 may be formed in the glass substrate 110.

(Step S130)
Next, in order to increase the diameter of the initial through hole 120, the initial through hole 120 is etched using a first etching solution (hereinafter referred to as “first etching process” or “first etching step”). Called).

  The type of the first etching solution is not particularly limited as long as the initial through hole 120 can be appropriately etched. For example, the first etching solution may be an acid solution containing hydrofluoric acid. The first etching solution may be a mixed acid solution containing at least one other acid in addition to hydrofluoric acid. For example, the first etching solution may be a mixed acid solution of hydrofluoric acid and hydrochloric acid or a mixed acid solution of hydrofluoric acid and nitric acid.

The etching rate V ₁ of the first etching solution with respect to the glass substrate 110 in the first etching process is, for example, 0.5 μm / min or less, preferably 0.2 μm / min or less, and preferably 0.02 μm / min. The following is more preferable.

  The first etching step may be performed at any suitable temperature, and the processing temperature may be, for example, room temperature.

  The first etching step may be performed, for example, by selectively supplying the first etching solution into the initial through hole 120 (hereinafter, such a method is referred to as “local etching process (method)”). Called). In the local etching processing method, the diameter of the initial through hole 120 can be expanded without changing the thickness of the glass substrate 110. For example, an etching protective film may be attached and etched so as not to block the initial through hole 120.

Alternatively, the first etching step may be performed by exposing the entire glass substrate 110 to the first etching solution (hereinafter, such a method is referred to as “total etching process (method)”). For example, the first etching step may be performed by immersing the glass substrate 110 having the initial through-hole 120 in a bath containing the first etching solution (dip method). Alternatively, the first etching step may be a method (shower type) in which the first etching solution is directly applied to the glass substrate. If the overall etching method, the thickness itself of the glass substrate 110 is also changed from _{d 0} to _{d 1} (decreases).

  In the first etching step, an ultrasonic wave may be applied to the glass substrate 110, the glass substrate 110 may be vibrated, or an etching solution may be bubbled. Thereby, more uniform etching becomes possible.

  Hereinafter, as an example, a case where the first etching process is performed by the overall etching method will be described.

  In FIG. 6, the cross section of the glass substrate 110 after the 1st etching process by the whole etching processing method is shown typically.

As shown in FIG. 6, the glass substrate 110 changes to the thickness d ₁ by the first etching step. That is, the glass substrate 110 has a first new surface 113 and a second new surface 115.

  Further, the initial through hole 120 changes to the first through hole 130. The first through hole 130 extends from the first opening 132 formed in the first new surface 113 to the second opening 134 formed in the second new surface 115.

Here, the first manufacturing method is characterized in that the ratio d ₁ / R _t1 is in the range of 10 to 20 when the diameter of the first opening 132 is R _t1 . The ratio d ₁ / R _t1 is more preferably in the range of 10-15.

By setting the ratio d ₁ / R _t1 in such a range, it is possible to significantly suppress the narrowed portion that can be formed in the through hole in the subsequent step S140.

That is, in the first etching step, the initial through hole 120 is expanded so that the ratio d ₁ / R _t1 is 20 or less, so that the first through hole 130 is expanded in the second etching step. It is possible to suppress the occurrence of a marked stenosis.

Note that the ratio d ₁ / R _{t1 is set} to 10 or more even if the first etching process is performed until the ratio d ₁ / R _t1 is less than 10, the second etching process has almost no change. This is because it does not occur. That is, by setting the ratio d ₁ / R _t1 to 10 or more, the processing time of the first etching process can be shortened.

  The first new surface 113 of the glass substrate obtained by the entire etching method as described above may be particularly referred to as “a surface corresponding to the first surface of the glass substrate”. Similarly, the second nascent surface 115 may be specifically referred to as a “surface corresponding to the second surface of the glass substrate”.

(Step S140)
Next, in order to further increase the diameter of the first through hole 130, that is, to expand the through hole to a desired diameter, the first through hole 130 is etched using the second etching solution ( Hereinafter, referred to as “second etching process” or “second etching step”).

  The second etching step may be performed by a local etching method or an overall etching method as in the case of the first etching step described above. Further, the second etching step may be the same processing method (method) as the first etching step, or may be a different processing method (method). For example, the first etching step may be a dip method, and the second etching step may be a shower method. In the first etching step, since the processing time tends to be long, the dip method is preferable from the viewpoint of productivity (cost). The second etching step is preferably a shower method because it is easy to adjust the hole diameter while suppressing a decrease in the thickness of the glass substrate.

  Here, a case where the second etching process is performed by the whole etching method will be described as an example.

In the overall etching processing method, the second etching step may be performed, for example, by immersing the glass substrate 110 having the first through hole 130 in a bath containing the second etching solution. As a result, the thickness of the glass substrate 110 changes (decreases) from d ₁ to d ₂ .

  For example, the second etching solution may be an acid solution containing hydrofluoric acid. Further, the second etching solution may be a mixed acid solution containing at least one other acid in addition to hydrofluoric acid. The mixed acid solution may be the same as the first etching solution. The second etching step may be performed at any suitable temperature, and the processing temperature may be, for example, room temperature.

  Here, the second etching solution is selected from those that can increase the etching rate for the glass substrate 110 as compared with the first etching solution.

For example, the etching rate V ₂ to the glass substrate 110 of the second etching solution in the second etching treatment may be three times or more the etching rate V ₁ to the glass substrate 110 of the first etching solution described above, 10 times or more is preferable and 100 times or more is more preferable. For example, the etching rate V ₂ of the second etching solution with respect to the glass substrate 110 is 5.0 μm / min or less, preferably 2.0 μm / min or less, and more preferably 1.5 μm / min or less. preferable. Etching rate _{V 2,} for example, may range from 1.0 .mu.m / min ～1.5Myuemu / min.

  FIG. 7 schematically shows a cross section of the glass substrate 110 after the second etching step.

As shown in FIG. 7, the glass substrate 110 is changed to a thickness d ₂ by the second etching step. That is, the glass substrate 110 has a third new surface 117 and a fourth new surface 119.

  In addition, the first through hole 130 changes to the second through hole 140. The second through hole 140 extends from the third opening 142 formed in the third nascent surface 117 to the fourth opening 144 formed in the fourth nascent surface 119.

  Through the above steps, the glass substrate 110 in which the second through hole 140 having a desired dimension is formed can be manufactured.

  Here, in the first manufacturing method, the through-hole (second through-hole 140) is formed through at least two stages of etching processes of the first etching process and the second etching process.

Among them, in the first etching step, using the etching rate V ₁ is a relatively small first etching solution, the initial holes 120 are etched.

First etching solution, the etching rate V ₁ is relatively small, it is necessary to time corresponding to the etching process. Therefore, the concentration diffusion of the first etching solution in the initial through hole 120 occurs relatively quickly. That is, since the first etching solution has a relatively low etching rate V ₁ with respect to the glass substrate 110, the glass substrate 110 near the first initial opening 122 and the second initial opening 124 of the initial through hole 120 is etched. Compared to the first etching solution, the first etching solution diffuses relatively quickly into the initial through hole 120. Therefore, the difference between the degree to which the glass substrate 110 near the first initial opening 122 and the second initial opening 124 is etched and the degree to which the glass substrate 110 is etched at the center of the initial through hole 120 is reduced. Thereby, the product by the etching reaction is easily diffused from the inside of the initial through hole 120 to the outside, and the stagnation inside the initial through hole 120 is significantly suppressed.

  Therefore, the first through hole can be expanded to a sufficient diameter while suppressing the conspicuous occurrence of the narrowed portion in the initial through hole by the first etching step.

Then, in the second etching process, a relatively large second etching solution etching rate V ₂ is used.

  However, the initial through-hole 120 has already been sufficiently expanded by the first etching process. For this reason, in the second etching step, the second etching solution can be distributed relatively quickly and uniformly in the first through holes 130. In addition, the product due to the etching reaction quickly moves from the inside of the first through hole 130 and is significantly suppressed from staying in the first through hole 130.

  Therefore, the first through-hole 130 is etched relatively uniformly, and a conspicuous narrowed portion is hardly generated in the first through-hole 130 even in the second etching step.

  As a result of the above, in the first manufacturing method, the formation of the narrowed portion can be significantly suppressed compared to the case where the initial through hole is expanded only by a single etching step as in the prior art, and the shape is relatively It is possible to form a uniform through hole.

  The method according to an embodiment of the present invention is effective when an initial hole (void array) having a relatively high aspect ratio is formed, particularly when a UV laser or a short pulse laser is used. This is because if the aspect ratio of the initial holes is high, the concentration diffusion of the etching solution is less likely to proceed, and it is more difficult to supply the etching solution into the initial holes.

  In the above, with reference to FIGS. 3-7, an example of the manufacturing method of the glass substrate which has a through-hole by one Embodiment of this invention was demonstrated. However, the above description is merely an example, and it will be apparent to those skilled in the art that the present invention may be implemented in other modes.

  For example, in the above description, the initial hole formed in step S <b> 120 is the initial through hole 120. However, the initial hole may be a non-through hole and a void row composed of a plurality of voids arranged along the thickness direction of the glass substrate. In this case, a through hole is formed after the first etching step, and such a through hole is expanded by the second etching step.

  The first manufacturing method has a two-stage etching process. However, in the method for manufacturing a glass substrate having a through hole according to an embodiment of the present invention, the etching process may be performed in three or more stages. In this case, a first etching solution having a relatively low etching rate is used in the first etching step, and a second etching solution having an intermediate etching rate is used in the second etching step. In this etching step, a third etching solution having a relatively large etching rate may be used.

Furthermore, the manufacturing method of the glass substrate which has the said through-hole can be applied also to the method of forming a through-hole in a glass substrate.
(Method of manufacturing a glass substrate having a through hole according to another embodiment of the present invention)
A method of manufacturing a glass substrate having a through hole according to another embodiment of the present invention is a method of manufacturing a glass substrate having a through hole,
(1) having first and second surfaces facing each other, and irradiating laser light from the first surface side to form initial holes in the glass substrate;
(2) A step of performing a first wet etching process on the initial holes using the first etching solution,
As a result, a first through hole extending from the first surface of the glass substrate or the surface corresponding to the first surface to the second surface of the glass substrate or the surface corresponding to the second surface is formed. And the process
(3) A step of performing a second wet etching process on the first through hole using the second etching solution,
Thereby, the 2nd through-hole by which the 1st through-hole was etched is formed,
The second etching solution has a larger etching rate than the first etching solution with respect to the glass substrate;
It is a manufacturing method which has this.

  As described above, by making the second etching solution have a larger etching rate than the first etching solution with respect to the glass substrate, it is possible to form a through hole having a relatively uniform shape. . In particular, when a UV laser or a short pulse laser is used, an initial hole having a relatively high aspect ratio is formed. Therefore, the manufacturing method of this embodiment is effective.

  The manufacturing method of the glass substrate which has the said through-hole can be applied also to the method of forming a through-hole in a glass substrate.

In the present embodiment, the configuration of one embodiment with reference to FIGS. 3 to 7 described above can be combined as appropriate. Note that the description of the specific configuration is omitted because the description of the one embodiment described above can be applied mutatis mutandis.
(System for manufacturing a glass substrate having a through hole according to another embodiment of the present invention)
A system for manufacturing a glass substrate having a through hole according to another embodiment of the present invention includes:
A system for manufacturing a glass substrate having a through hole,
A laser processing system for forming an initial hole in the glass substrate by irradiating the glass substrate with laser light;
An etching system for forming a through hole by etching an initial hole with respect to the glass substrate,
The etching system includes:
A first etching system and a second etching system;
The first etching system is a system in which a first etching process using a first etching solution is performed,
The second etching system is a system in which a second etching process using a second etching solution having an etching rate larger than that of the first etching solution is performed on the glass substrate,
The etching system is a system configured to process the glass substrate with the second etching system after processing the glass substrate with the first etching system.

  The laser processing system preferably comprises a UV laser. The laser processing system may include a short pulse laser such as a picosecond laser or a femtosecond laser.

  As described above, by using an etching solution having a larger etching rate than the first etching solution for the glass substrate as the second etching solution, it is possible to form a through hole having a relatively uniform shape. it can. In particular, when a UV laser or a short pulse laser is used, an initial hole having a relatively high aspect ratio is formed. Therefore, it is effective to form a glass substrate having a through hole using the system of this embodiment.

  The etching system preferably further comprises a cleaning system. It is preferable to perform the cleaning process by the cleaning system between the first etching process by the first etching system and the second etching process by the second etching system. Since the concentration of the etching solution used is different between the first etching process and the second etching process, it is preferable to wash between the two processes. For example, pure water is used for the cleaning process.

  The above system can also be applied to a method of forming a through hole in a glass substrate.

  This embodiment can combine the structure of the above-mentioned embodiment suitably. In addition, since the description of the above-mentioned embodiment can be applied mutatis mutandis, description of a specific configuration is omitted.

  Examples of the present invention will be described below. In the following description, Examples 1 to 4 are examples, and Example 5 is a comparative example.

(Example 1)
A glass substrate having through holes of a predetermined size was manufactured by the following method.

(Laser irradiation)
First, a glass substrate (non-alkali glass substrate) having a length of 50 mm × width of 50 mm × thickness (d ₀ ) of 400 μm was prepared.

Next, UV laser light was irradiated from the first surface (one surface of 50 mm length × 50 mm width) side of the glass substrate to form initial through holes. The diameter R _t0 of the first initial opening (opening on the first surface side) of the initial through-hole is about 13 μm, and the diameter R _b0 of the second initial opening on the opposite second surface is about 3 μm. Met. Therefore, in this glass substrate, the ratio d ₀ / R _t0 is about 30.8.

(First etching process)
Next, a first etching process was performed on the obtained glass substrate.

  The first etching solution was a 0.4 wt% hydrofluoric acid solution. The first etching treatment was performed by immersing the glass substrate in this hydrofluoric acid solution for 80 minutes. The processing temperature is room temperature. Note that the glass substrate was etched in a stationary state (that is, a state in which no vibration was applied).

Thereby, the initial through hole was etched, and the first through hole was obtained. The glass substrate itself was also etched, resulting in a thickness d ₁ = 390 μm.

The diameter R _t1 of the first opening of the first through hole on the first surface side of the glass substrate is 25.1 μm, and the diameter R _b1 of the second opening on the second surface side is 10.4 μm. Met. Thus, the ratio d ₁ / R _t1 is about 15.6.

(Second etching process)
Next, a second etching process was performed on the glass substrate.

The second etching solution was a 2 wt% hydrofluoric acid solution. The second etching process was performed by immersing the glass substrate in this hydrofluoric acid solution for 25 minutes. The processing temperature is room temperature. Note that the glass substrate was etched in a stationary state (that is, a state in which no vibration was applied). The etching rate V2 of the _second etching solution is about 10 times the etching rate V1 of the _first etching solution.

Thereby, the 1st through-hole was etched and the 2nd through-hole was obtained. The glass substrate itself was also etched, resulting in a thickness d ₂ = 360 μm.

The diameter R _t2 of the third opening of the second through hole on the first surface side of the glass substrate is 46.3 μm, and the diameter R _b2 of the fourth opening on the second surface side is 33.8 μm. Met. Therefore, the ratio d ₂ / R _t2 is about 7.8.

(Example 2)
A glass substrate having through holes of a predetermined size was manufactured in the same manner as in Example 1.

  However, in Example 2, the etching time with the first etching solution was 120 minutes in the first etching step. In the second etching step, the etching time with the second etching solution was 21 minutes.

The thickness d ₁ of the glass substrate after the first etching step was 385 μm. Further, the diameter R _t1 of the first opening of the first through hole on the first surface side of the glass substrate is 28.7 μm, and the diameter R _b1 of the second opening on the second surface is 15. It was 6 μm. Therefore, the ratio d ₁ / R _t1 is about 13.4.

On the other hand, the thickness d ₂ of the glass substrate after the second etching step was 360 μm. The diameter R _t2 of the third opening of the second through hole on the first surface side of the glass substrate is 46.0 μm, and the diameter R _b2 of the fourth opening on the second surface side is 34.3 μm. Met. Therefore, the ratio d ₂ / R _t2 is about 7.8.

(Example 3)
A glass substrate having through holes of a predetermined size was manufactured in the same manner as in Example 1.

  However, in this example 3, the etching time with the first etching solution was 210 minutes in the first etching step. In the second etching step, the etching time with the second etching solution was 8 minutes.

The thickness d ₁ of the glass substrate after the first etching step was 370 μm. The diameter R _t1 of the first opening of the first through hole on the first surface side of the glass substrate is 36.8 μm, and the diameter R _b1 of the second opening on the second surface side is 23 .1 μm. Therefore, the ratio d ₁ / R _t1 is about 10.

On the other hand, the thickness d ₂ of the glass substrate after the second etching step was 360 μm. The diameter R _t2 of the third opening of the second through hole on the first surface side of the glass substrate is 46.4 μm, and the diameter R _b2 of the fourth opening on the second surface side is 33.3 μm. Met. Therefore, the ratio d ₂ / R _t2 is about 7.8.

(Example 4)
A glass substrate having through holes of a predetermined size was manufactured in the same manner as in Example 1.

  However, in Example 4, in the first etching step, the etching time with the first etching solution was 40 minutes. In the second etching step, the etching time with the second etching solution was 30 minutes.

The glass substrate thickness d ₁ after the first etching step was about 395 μm. The diameter R _t1 of the first opening of the first through hole on the first surface side of the glass substrate is 18.9 μm, and the diameter R _b1 of the second opening on the second surface side is 7 .6 μm. Thus, the ratio d ₁ / R _t1 is about 20.9.

On the other hand, the thickness d ₂ of the glass substrate after the second etching step was 360 μm. Further, the diameter R _t2 of the third opening of the second through hole on the first surface side of the glass substrate is 45.6 μm, and the diameter R _b2 of the fourth opening on the second surface side is 34. 0.0 μm. Accordingly, the ratio d ₂ / R _t2 is about 7.9.

(Example 5)
A glass substrate having through holes of a predetermined size was manufactured in the same manner as in Example 1.

  However, in Example 5, the first etching process was not performed. That is, after irradiating UV laser light to form an initial through hole in the glass substrate, only the second etching step was performed on the glass substrate. In the second etching step, the etching time with the second etching solution was 33 minutes.

The thickness d ₂ of the glass substrate after the second etching step was 360 μm. Further, the diameter R _t2 of the third opening of the second through hole on the first surface side of the glass substrate is 45.6 μm, and the diameter R _b2 of the fourth opening on the second surface side is 32. 0.7 μm. Accordingly, the ratio d ₂ / R _t2 is about 7.9.

  Table 1 below collectively shows the thickness of the glass substrate in each step, the diameter of the opening of the through hole, and the like when manufacturing the glass substrate in Examples 1 to 5.

（評価）
前述のようにして製造された各ガラス基板において、第２の貫通孔の形態を観察した。より具体的には、第２の貫通孔において、延伸方向に垂直な断面が最も小さい狭窄部の直径Ｒ_ｃを測定した。

(Evaluation)
In each glass substrate manufactured as described above, the form of the second through hole was observed. More specifically, in the second through-hole, the cross section perpendicular to the stretching direction was measured diameter R _c of the smallest constriction.

  The results are summarized in Table 2. Note that, in any of the glass substrates in Examples 1 to 5, the narrowed portion of the second through hole was present at the substantially central portion of the entire length of the through hole.

この結果から、例５では、第２の貫通孔の狭窄部の直径Ｒ_ｃは、極めて小さく、比Ｒ_ｃ／Ｒ_ｔ２は、０．４を下回ることがわかった。例４では、第２の貫通孔の狭窄部の直径Ｒ_ｃは、例５と比較して拡張されることがわかった。さらに、例１乃至例３では、第２の貫通孔の狭窄部の直径Ｒ_ｃは、有意に拡張されており、比Ｒ_ｃ／Ｒ_ｔ２は、少なくとも０．５を超えることがわかった。

From this result, it was found that in Example 5, the diameter R _c of the narrowed portion of the second through hole was extremely small, and the ratio R _c / R _t2 was less than 0.4. In Example 4, the diameter R _c of the constriction of the second through hole was found to be extended as compared with Example 5. Further, in Examples 1 to 3, it was found that the diameter R _c of the narrowed portion of the second through hole was significantly expanded, and the ratio R _c / R _t2 exceeded at least 0.5.

In this way, by performing the two-stage etching process, it is possible to suppress the remarkable occurrence of the narrowed portion of the through hole. Further, a two-stage etching process is performed, and a ratio d ₁ / R _t1 of the thickness d ₁ of the glass substrate after the first etching process and the diameter R _t1 of the first opening of the first through hole is set. It was confirmed that a through hole having a relatively uniform shape can be formed by setting the thickness within the range of 10 to 20.

DESCRIPTION OF SYMBOLS 10 Glass substrate 12 1st surface 14 2nd surface 20 Through-hole 22 1st opening 24 2nd opening 30 Expansion through-hole 32 1st opening 34 2nd opening 36 Constriction part 110 Glass substrate 112 1st Surface 113 first nascent surface 114 second surface 115 second nascent surface 117 third nascent surface 119 fourth nascent surface 120 initial through-hole 122 first initial opening 124 second initial opening 130 first Through hole 132 First opening 134 Second opening 140 Second through hole 142 Third opening 144 Fourth opening

Claims (15)

A method for producing a glass substrate having a through-hole,
(1) forming first holes in the glass substrate by irradiating laser light from the first surface side of the glass substrate having first and second surfaces facing each other;
(2) A first etching process is performed on the glass substrate using a first etching solution, and the second opening is formed from the first opening formed in the first surface from the initial hole. forming a first through hole extending to a second opening formed on the surface, when the thickness of the glass substrate and d _1, the diameter of the first opening and the R _t1, the ratio d ₁ / R _t1 is in the range of 10-20,
(3) After the step (2), a second etching solution is used for the glass substrate by using a second etching solution having an etching rate larger than that of the first etching solution. Performing a process to enlarge the first through hole;
A manufacturing method comprising: _2. The manufacturing method according to claim ₁ , wherein a ratio V ₂ / V ₁ of an etching rate V ₂ of the second etching solution to an etching rate V ₁ of the first etching solution is 3 or more. The manufacturing method according to claim 1, wherein an etching rate V ₁ of the first etching solution is 0.5 μm / min or less. The manufacturing method according to claim 1, wherein an etching rate V ₂ of the second etching solution is in a range of 1 μm / min to 5 μm / min. The manufacturing method according to claim 1, wherein the thickness d ₁ is smaller than the thickness d ₀ . The manufacturing method according to claim 1, wherein the thickness d ₀ is 0.3 mm or more. The manufacturing method according to claim 1, wherein the thickness d ₀ is 0.5 mm or less. When the said first diameter of the opening in the surface of the initial hole formed in the step (1) was R _t0, the ratio d _{0 /} R _t0 is 25 or more, one of the claims 1 to 7 The manufacturing method as described in any one.   The manufacturing method according to any one of claims 1 to 7, wherein the initial hole formed in the step (1) is a through hole or a void array. A method of forming a through hole in a glass substrate,
(1) forming first holes in the glass substrate by irradiating laser light from the first surface side of the glass substrate having first and second surfaces facing each other;
(2) A first etching process is performed on the glass substrate using a first etching solution, and the second opening is formed from the first opening formed in the first surface from the initial hole. forming a first through hole extending to a second opening formed on the surface, when the thickness of the glass substrate and d _1, the diameter of the first opening and the R _t1, the ratio d ₁ / R _t1 is in the range of 10-20,
(3) After the step (2), a second etching solution is used for the glass substrate by using a second etching solution having an etching rate larger than that of the first etching solution. Performing a process to enlarge the first through hole;
Having a method. 11. The method according to claim 10, wherein an etching rate V ₂ of the second etching solution is in a range of 1 μm / min to 5 μm / min. A system for manufacturing a glass substrate having a through hole,
A laser processing system for forming an initial hole in the glass substrate by irradiating the glass substrate with laser light;
An etching system for forming a through hole by etching an initial hole with respect to the glass substrate,
The etching system includes:
A first etching system and a second etching system;
The first etching system is a system in which a first etching process using a first etching solution is performed,
The second etching system is a system in which a second etching process using a second etching solution having an etching rate larger than that of the first etching solution is performed on the glass substrate,
The etching system is configured to process the glass substrate with the second etching system after processing the glass substrate with the first etching system. The etching system further includes a cleaning system,
The system of claim 12, wherein a cleaning process is performed by the cleaning system between the first etching process and the second etching process.   The system according to claim 12 or 13, wherein the laser processing system comprises one short pulse laser selected from a picosecond laser or a femtosecond laser.   14. A system according to claim 12 or claim 13, wherein the laser processing system comprises a UV laser.

Images