JP2013033889A - Through wiring board manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a through wiring board manufacturing method which can efficiently form a through wiring.SOLUTION: A manufacturing method of a through wiring board 10 comprises: a process of forming a first insulation layer 2 on a first surface 1a of a substrate 1; a process of forming a conductive film 3 on the first insulation layer 2; a process of forming a first mask part on another surface 1b of the substrate 1 so as to cause a partial region of the other surface to be exposed and surround the region, and forming a second mask part in the exposed region at a distance from the first mask; a process of forming a through hole 6 from the other surface 1b to the one surface 1a to cause the first insulation layer 2 to be exposed on a bottom 6b of the through hole 6 and forming, on the bottom 6b of the through hole 6, a salient 7 composed of the substrate 1 corresponding to the second mask part; a process of forming a second insulation layer 8 on inner walls of the through hole 6 and on the other surface 1b; a process of removing the first insulation layer 2 and the second insulation layer 8 on the bottom 6b of the through hole 6 to cause the conductive film 3 to be exposed in the through hole 6; and a process of forming a through wiring 9 in the through hole 6.

Description

 The present invention relates to a method for manufacturing a through wiring substrate.

  Conventionally, an electrode pad disposed on one surface of a semiconductor substrate, a through hole penetrating from the other surface of the semiconductor substrate to the entire surface, a through wiring electrically connected to the electrode pad at the bottom of the through hole, and a bottom portion of the through hole A through-wiring board provided with a concavo-convex portion provided on the substrate is known (for example, see Patent Document 1). In this through wiring board, an uneven portion is provided at the bottom of the through hole to improve electrical and mechanical connection between the through wiring and the electrode pad.

  In such a method of manufacturing a through wiring substrate, a mask pattern A for forming a concave hole is formed on the back surface of the semiconductor substrate, and the back surface side of the semiconductor substrate is etched to be shallower than the thickness of the semiconductor substrate. A step of forming a concave hole, a step of forming a mask pattern B for forming a small through-hole having an irregular shape at the bottom of the concave hole, and etching the back side of the semiconductor substrate again to form the bottom of the concave hole In this method, the steps of forming a small through hole having a concave and convex shape are sequentially performed.

JP 2009-64820 A

  However, the above method for manufacturing a through wiring substrate requires a step of forming a mask pattern A for forming a concave hole and a step of forming a mask pattern B for forming a small through hole. And an etching process for forming small through holes are required. That is, in order to provide a small through hole having irregularities at the bottom of the through hole, it is necessary to repeat the formation and etching of the mask pattern at least twice. As described above, the conventional method has a problem that the through wiring cannot be efficiently formed because of the large number of steps.

  This invention is made | formed in view of the said situation, Comprising: It aims at provision of the manufacturing method of the penetration wiring board which can form a penetration wiring efficiently.

The method for manufacturing a through wiring board according to claim 1 of the present invention includes a first insulating layer forming step of forming a first insulating layer on one surface of the substrate, and a conductive film forming a conductive film on the first insulating layer. And forming a first mask portion on the other surface of the substrate so that a part of the region is exposed and surrounds the region, and the first mask portion is formed in the exposed region. A mask pattern forming step for forming a second mask portion that is spaced apart and a first etching on the other surface side to dig down the exposed region and form a through hole from the other surface toward the one surface. A through hole forming step of exposing the first insulating layer to the bottom of the through hole and forming a convex portion made of the substrate corresponding to the second mask portion at the bottom of the through hole; A second insulating layer is formed on the inner wall of the hole and the other surface. A second insulating layer forming step and second etching on the other surface side, thereby removing the first insulating layer and the second insulating layer at the bottom of the through hole, and conducting the conductive in the through hole. A conductive film exposing step of exposing the film; and a through wiring forming step of forming a through wiring connected to the conductive film by disposing a conductive material in the through hole.
According to this manufacturing method, it is not necessary to separately form a mask pattern for forming a through hole in which a through wiring is provided and a mask pattern for forming a convex portion, and the through hole is formed in the substrate. Since the through-hole and the convex portion are formed simultaneously by one-time etching, the number of processes can be reduced as compared with the prior art.

According to a second aspect of the present invention, there is provided a through wiring substrate manufacturing method according to the first aspect, further comprising a seed layer forming step of forming a seed layer made of metal on a surface of the convex portion.
According to this manufacturing method, it is possible to manufacture a through wiring substrate in which the adhesion (adhesiveness) between the through wiring formed in the through hole and the convex portion is further improved. In the through wiring substrate, the convex portion further improves the adhesion between the through wiring and the conductive film at the bottom of the through hole in which the conductive film is disposed.

  According to the method for manufacturing a through wiring substrate according to the present invention, there is no need to separately form a mask pattern for forming a through hole in which a through wiring is provided and a mask pattern for forming a convex portion. Furthermore, since the through hole and the convex portion are simultaneously formed by one etching, the number of steps can be reduced as compared with the conventional method. Moreover, in the through-hole forming step, since the convex portion is formed while leaving a part of the substrate, it is not necessary to separately attach another member different from the substrate, the material cost can be reduced, and the manufacturing process can be simplified. .

It is typical sectional drawing which shows the 1st insulating layer formation process and conductive film formation process in 1st embodiment of this invention. The mask pattern formation process in 1st embodiment of this invention is shown, (a) is typical top view, (b) is typical sectional drawing which follows the AA line of (a). It is typical sectional drawing which shows the through-hole formation process in 1st embodiment of this invention. In 1st embodiment of this invention, it is typical sectional drawing which shows the state which removed the mask pattern. It is typical sectional drawing which shows the 2nd insulating layer formation process in 1st embodiment of this invention. It is typical sectional drawing which shows the electrically conductive film exposure process in 1st embodiment of this invention. It is typical sectional drawing which shows the penetration wiring formation process in 1st embodiment of this invention. It is typical sectional drawing which shows the penetration wiring board manufactured by 2nd embodiment of this invention.

   The present invention will be described below based on preferred embodiments with reference to the drawings.

<< Manufacturing method of through wiring board >>
The method for manufacturing a through wiring substrate according to the present invention includes a first insulating layer forming step of forming a first insulating layer on one surface of the substrate, a conductive film forming step of forming a conductive film on the first insulating layer, A first mask portion is formed on the other surface of the substrate so that a part of the region is exposed and surrounds the second region, and the second mask is spaced from the first mask portion in the exposed region. A mask pattern forming step for forming a portion and a first etching on the other surface side to dig down the exposed region and form a through hole from the other surface of the substrate to the one surface, A through hole forming step of exposing the first insulating layer at the bottom of the hole and forming a convex portion made of the substrate corresponding to the second mask portion at the bottom of the through hole; and an inner wall of the through hole; Second insulation forming a second insulation layer on the one surface And forming the conductive film in the through hole by removing the first insulating layer and the second insulating layer at the bottom of the through hole by performing a second etching on the other surface side in the forming step A conductive film exposing step of exposing, and a through wiring forming step of forming a through wiring connected to the conductive film by disposing a conductive material in the through hole.

In a group of the first insulating layer forming step, the conductive film forming step, the mask pattern forming step, and the through hole forming step, it is preferable to perform each step in this order.
In another group of the second insulating layer forming step, the conductive film exposing step, and the through wiring forming step, it is preferable to perform each step in this order. The second insulating layer forming step for insulating the inner wall of the through hole may be performed after the conductive film exposing step, but in this case, another step (another step of removing the second insulating layer formed on the conductive film again) A conductive film exposing step) is required. Therefore, it is better to perform each process in the said preferable order from a viewpoint of improving manufacturing efficiency.
Hereinafter, each process will be described.

<First embodiment>
[First insulating layer forming step]
The first insulating layer forming step is a step of forming the first insulating layer 2 on the one surface 1 a of the substrate 1.
In this step, a substrate 1 made of silicon (Si) is prepared, and a first insulating layer 2 made of an oxide film (SiO ₂ film) is formed on the surface 1a (see FIG. 1).
The method for forming the oxide film is not particularly limited, and for example, a known method such as PECVD (Plasma Enhanced Chemical Vapor Deposition) method can be applied.

[Conductive film forming step]
The conductive film forming step is a step of forming the conductive film 3 on the first insulating layer 2.
A conductive film 3 forming an electrode pad or surface wiring having a desired shape is formed on the first insulating layer 2 (see FIG. 1).
On the one surface 1a side of the substrate 1, the region where the conductive film 3 is formed includes a region directly above the bottom 6b of the through hole 6 formed in the subsequent through hole forming step.

  The material which comprises the electrically conductive film 3 is not specifically limited, For example, the thin film which consists of metals, and the thin film which consists of conductive resins are mentioned. Especially, the thin film which consists of metals is preferable from a viewpoint of the ease of formation and the intensity | strength of an electrically conductive film. The metal is preferably aluminum (Al), copper (Cu), an alloy containing aluminum as a main component, or the like. Al and Cu are highly conductive and easy to process. The method for forming the conductive film 3 is not particularly limited, and for example, a known film formation method such as a sputtering method, a CVD method, or a plating method can be applied. Further, the method for patterning the conductive film 3 into a desired shape is not particularly limited, and a known lithography method can be applied.

[Mask pattern forming process]
In the mask pattern forming step, the first mask portion 4 is formed on the other surface 1b of the substrate 1 so that a part of the region 1c is exposed and surrounds the region 1c, and in the exposed region 1c. This is a step of forming the second mask portion 5 spaced from the first mask portion 4 (see FIG. 2).
Each mask constituting the first mask portion 4 and the second mask portion 5 can be formed at a predetermined position by, for example, applying a photoresist to the other surface 1b with a spin coater or the like and photolithography using the photomask.

  In a partial region 1c of the other surface 1b of the substrate 1, the photomask is adjusted so that the photoresist is not cured except for a local region to be the second mask portion 5. At this time, it is preferable to use a photomask adjusted so that a transmission amount of light irradiated to the local region gradually changes. As a result, a dome-shaped second mask 5 as shown in FIG. 2 can be formed. By forming the dome-shaped second mask portion 5, it is easier to form the convex portion 7 so that the tip of the convex portion 7 has an acute angle in the formation of the convex portion 7 in the subsequent stage. In addition, since the degree of hardening of the photoresist can be adjusted by controlling the amount of transmission of light irradiated to the local region, the thickness of the second mask portion 5 after development is set to the first mask. It can be formed thinner than the portion 4.

After the light irradiation, the uncured photoresist is removed by using a developing solution, whereby a region 1c surrounded by the opening 4a of the first mask portion 4 and a first mask in the region 1c. The second mask part 5 at a position separated from the part 4 is obtained (see FIG. 2).
In the opening 4a of the first mask portion 4, the region 1c where the other surface 1b of the substrate 1 is exposed is a region in which a through hole is formed in a subsequent process (hereinafter also referred to as a “through hole forming region”). It is. Therefore, when a plurality of through holes are formed, a plurality of regions 1c are formed. At this time, the size and shape of the opening 4a corresponding to each through hole may be the same or different.
The shape and size of the opening 4a are not particularly limited, and are appropriately adjusted according to the size and shape of the target through wiring. For example, the shape of the opening 4a is circular in plan view as shown in FIG.

In the mask pattern forming step, the first mask portion 4 is formed, and at the same time, the second mask portion 5 is formed in the through hole forming region 1c.
The shape and size (dimension, thickness) of the second mask portion 5 are not particularly limited, and can be appropriately adjusted according to the size and shape of the convex portion 7 formed on the bottom portion of the through hole in the subsequent step. For example, the shape of the second mask portion 5 is preferably a dome shape (hemispherical shape) as shown in FIG. In photolithography for forming the second mask portion, the second mask portion 5 having an arbitrary shape and size can be formed by adjusting the photomask and adjusting the exposure area and the exposure amount. Further, it is preferable that the thickness of the second mask portion 5 is made thinner than the thickness of the first mask portion 4. By making the thickness of the second mask portion 5 thinner than the thickness of the first mask portion 4, the first mask portion 4 remains in the etching process of the substrate 1 in the through-hole forming step described later. 2 Mask portion 5 can be eliminated. As a result, the second mask portion 5 does not remain after the etching process is finished, and the second mask portion 5 itself can be prevented from becoming a dust.

  The number of the second mask portions 5 formed in the region 1c corresponds to the number of the convex portions 7 formed in the subsequent process by 1: 1. That is, when the plurality of second mask portions 5 are formed, the same plurality of convex portions 7 can be formed.

  When the number of the second mask portions 5 formed in the region 1c is one, the second mask portion 5 is preferably provided at the center in the region 1c or in the vicinity thereof. With this arrangement, the convex portion 7 formed in the subsequent process can be formed at a corresponding position of the bottom portion 6b of the through hole 6, that is, at the center of the bottom portion 6b or in the vicinity thereof. Since the convex part 7 functions to enhance the adhesion (adhesiveness) between the through wiring 9 and the conductive film 3, it is preferable to arrange the convex part 7 at the center or in the vicinity thereof because the adhesion can be improved without deviation at the bottom 6b. Further, in order to allow a current flowing between the through wiring 9 and the conductive film 3 to flow smoothly, the convex portion 7 is preferably arranged at the center or in the vicinity of the bottom portion 6 b of the through hole 6.

  When a plurality of second mask portions 5 are formed in the region 1c, it is preferable that the second mask portions 5 are arranged evenly distributed in the region 1c. With this arrangement, the plurality of convex portions 7 formed in the subsequent process can be formed in an evenly distributed arrangement at the bottom 6 b of the through hole 6. Since the convex portion 7 functions to enhance the adhesion (adhesiveness) between the through-wiring 9 and the conductive film 3, it is preferable to disperse the projections 7 evenly so that the adhesion can be improved without deviation at the bottom 6b. Further, in order to allow a current flowing between the through-wiring 9 and the conductive film 3 to flow smoothly, it is preferable that the convex portions 7 are arranged evenly distributed in the bottom portion 6 b of the through-hole 6.

The number of the second mask portions 5 provided in the region 1c is usually preferably 1 to 6, although it depends on the size of the region 1c and the relative size relationship of the second mask portion 5. When the number is within this range, it is easier to disperse and arrange evenly in the region 1c.
The size of the plurality of second mask portions 5 formed may be the same or different.

Of the area in the region 1c, the area (occupied area) occupied by one or more second mask portions 5 is preferably 5 to 25%, and more preferably 5 to 15%.
If it is equal to or more than the above lower limit value, the structural strength of the convex portion 7 can be further increased at the bottom portion 6b of the through hole 6 formed in the subsequent step, and the adhesion between the through wiring 9 and the conductive film 3 can be further increased. Can be improved.
If it is not more than the above upper limit value, it is possible to sufficiently secure an area where the through wiring 9 and the conductive film 3 are in contact with each other at the bottom 6b of the through hole 6 formed in the subsequent step, and reliability of electrical connection. Can be enhanced.

[Through hole forming step]
In the through hole forming step, the exposed region 1c is dug down by performing first etching on the other surface 1b side, and the through hole 6 is formed from the other surface 1b toward the one surface 1a. This is a step of exposing the first insulating layer 2 to 6b and forming the convex portion 7 made of the substrate 1 corresponding to the second mask portion 5 on the bottom 6b of the through hole 6 (see FIG. 3).

  As the first etching method, a dry etching method is preferable. In particular, by adopting the DRIE (Deep Reactive Ion Etching) method, it is possible to easily form fine holes with a high aspect ratio. As the DRIE method, a method in which by-products generated in the etching process are deposited alternately on the side walls of the through holes and etching are alternately repeated (Bosch process method), and the substrate is cooled to near the liquid nitrogen temperature and processed. There is a method of performing (cryo process method). If the latter method is adopted, the inner wall of the through hole is formed in a moderately inclined shape, and a second insulating layer and a through wiring to be described later can be easily formed in the through hole. As the etching gas, one that preferentially etches the substrate 1 over the first mask portion 4 and the second mask portion 5 is used. When the through hole 6 is formed by etching the other surface 1b side of the substrate 1 by the dry etching method, at the position corresponding to the second mask portion 5 formed in the through hole forming region 1c, At the bottom 6 b of the through hole 6, a part of the substrate 1 remains without being etched, and a convex portion 7 is formed.

As the first etching proceeds, the etching gradually proceeds in the depth direction of the exposed region 1 c of the substrate 1. In the middle stage, in the cross-sectional view of the substrate 1, side etching proceeds directly below the second mask portion 5, and the side etching proceeds for a longer time as the distance to the second mask portion 5 is closer. As a result, the substrate 1 has a conical shape immediately below the second mask portion 5. As the side etching further proceeds, the height of the substrate 1 having the conical shape decreases while maintaining its shape. The second mask portion 5 is gradually decomposed as the first etching proceeds, and disappears completely until the etching is completed.
As a result, as shown in FIG. 3, a cone-shaped convex portion 7 having a sharp tip is formed.

The shape of the through hole 6 is not particularly limited. For example, as shown in FIG. 3, the through hole 6 may have a tapered shape in which the inner diameter (opening diameter) gradually increases from one surface 1 a to the other surface 1 b.
The shape of the convex portion 7 is not particularly limited. For example, as shown in FIG. 3, the convex portion 7 has a cone shape such as a cone or a polygonal pyramid that protrudes toward the other surface 1 b side of the substrate 1 with the conductive film 3 side as a base. Can do.

  In the through-hole forming step, it is not necessary to provide a member different from the substrate 1 by forming the convex portion 7 while leaving a part of the substrate 1, so that the material cost can be reduced. Furthermore, since the through-hole 6 and the convex part 7 can be formed by one etching, a manufacturing process can be simplified.

  In the wiring board 10 manufactured according to the present invention, as can be clearly understood from FIG. 3, the first insulating layer 2 is formed between the convex portion 7 and the conductive film 3. The first insulating layer 2 contributes to improving the adhesion (adhesiveness) between the convex portion 7 and the conductive film 3.

  After the formation of the through hole 6 and the convex portion 7, the first mask portion 4 left on the other surface 1b of the substrate 1 is peeled off using an organic solvent or the like (see FIG. 4).

[Second insulating layer forming step]
The second insulating layer forming step is a step of forming the second insulating layer 8 on the inner wall 6c and the other surface 1b of the through hole 6 (see FIG. 5).
The second insulating layer 8 is formed in order to prevent an electrical short circuit between the through wiring 9 and the inner wall 6c of the through hole 6 that are formed in a subsequent process.
The method for forming the second insulating layer 8 is not particularly limited, and may be the same as the method for forming the first insulating layer 2 described above.

[Conductive film exposure process]
In the conductive film exposing step, second etching is performed on the other surface 1 b side to remove the first insulating layer 2 and the second insulating layer 8 at the bottom 6 b of the through hole 6, and the conductive film is conductive in the through hole 6. This is a step of exposing the film 3 (see FIG. 6).

As the second etching method, a dry etching method is preferable. As the etching gas, one that preferentially etches the first insulating layer 2 and the second insulating layer 8 over the substrate 1 (convex portion 7) is used. By etching the other surface 1b side of the substrate 1 by a dry etching method, the first insulating layer 2 and the second insulating layer 8 can be removed at the bottom 6b of the through hole 6 to expose the conductive film 3. . At this time, since the convex portion 7 is made of the same material as the substrate 1, it remains without being etched. Furthermore, since the convex part 7 functions as a mask, the first insulating layer 2 formed between the convex part 7 and the conductive film 3 immediately below the convex part 7 is left without being removed.
The second insulating layer 8 formed on the surface 7a of the convex portion 7 may be removed by the dry etching or may not be removed.

In the second dry etching, for example, the second insulating layer 8 formed on the inner wall 6c of the through hole 6 is performed by performing etching under conditions with high vertical anisotropy, for example, by applying a bias to draw ions to the substrate side. Can be left without removing. Thereby, the insulation of the inner wall 6c of the through-hole 6 is maintained.
At this time, the second insulating layer 8 disposed on the other surface 1b of the substrate 1 is also etched, but may not be completely removed. Usually, the insulating layer formed on the bottom 6b of the through hole 6 is thinner than the insulating layer formed on the other surface 1b, so that even after the insulating layer on the bottom 6b is removed, An insulating layer is left on the surface 1b.

[Through wiring formation process]
The through wiring forming step is a step of forming a through wiring 9 connected to the conductive film 3 by disposing a conductive substance in the through hole 6 (see FIG. 7).
A conductive material is disposed in the through hole 6 so as to connect to the conductive film 3 and cover the convex portion 7, thereby forming the through wiring 9. The through wiring 9 is a wiring that electrically connects the one surface 1 a and the other surface 1 b of the substrate 1.
The through wiring substrate 10 shown in FIG. 7 is obtained by the manufacturing method including the above steps.

A method for forming the through wiring 9 by disposing a conductive substance in the through hole 6 is not particularly limited, and a known method can be applied. For example, techniques such as plating, sputter deposition, CVD, and molten metal filling can be applied.
As the conductive material, those used in conventional through wiring can be applied. For example, a metal is mentioned. When the through wiring 9 is formed by the plating method, it is preferable to use copper (Cu) as the conductive material. This is because the formation is easy and the adhesion to the conductive film 3 is excellent.

[Seed layer formation process]
The production method of the present invention preferably includes a seed layer forming step of forming a seed layer made of metal on the surface 7 a of the convex portion 7 before forming the through wiring 9.
By covering the surface of the convex portion 7 with the seed layer, the adhesion between the convex portion 7 and the conductive material constituting the through wiring 9 can be enhanced. This effect is particularly remarkable when the conductive material is a metal. The metal constituting the seed layer and the metal used as the conductive material preferably include the same metal. This is because the adhesion can be further improved.
The method for forming the seed layer is not particularly limited, and for example, sputtering is suitable.
When the through wiring 9 is formed by the plating method, a seed layer made of metal is formed in the through hole 6 in advance by sputtering or the like. The seed layer covers the surface 7a of the convex portion 7, whereby the above-described effect is obtained.
The second insulating layer 8 described above may or may not remain on the surface of the convex portion 7a before the seed layer is formed. In any case, the effect of the seed layer can be obtained.

In the method of manufacturing the through wiring substrate according to the present embodiment, the first mask portion 4 for forming the through hole 6 and the second mask portion 5 for forming the convex portion 7 are simultaneously formed in the mask pattern forming step. To do. Further, in the through hole forming step, the through hole 6 and the convex portion 7 are simultaneously formed by one etching. According to this manufacturing method, the number of steps can be reduced as compared with the conventional method. Therefore, the manufacturing efficiency of the through wiring substrate 10 can be increased.
In addition, the through wiring board 10 manufactured according to the present embodiment is provided with a convex portion 7 protruding from the bottom surface 6 b of the through hole 6 to the other surface 1 b side (inside the through hole 6) of the substrate 1. The convex portion 7 is connected to the conductive film 3 exposed in the through hole 6 and the through wiring 9 is formed so as to cover the convex portion 7. Therefore, the adhesion (adhesion) of the conductive film 3 to the through wiring 9 is formed. Improved). Accordingly, the conductive film 3 is firmly fixed to the through wiring 9, and the through wiring 9 and the conductive film 3 are not easily separated. As a result, it is possible to prevent a problem that the electrical connection between the through wiring 9 and the conductive film 3 is broken.

<Second Embodiment>
With reference to FIG. 8, 2nd embodiment of the manufacturing method of the penetration wiring board concerning the present invention is described. 8, the same components as those shown in FIGS. 1 to 7 are denoted by the same reference numerals, and the description thereof is omitted.
The present embodiment is different from the first embodiment described above in that, in the mask pattern forming process, the first mask portion 4 is formed on the other surface 1b of the substrate 1 so that a part of the region 1c is exposed. In addition, three second mask portions 5 are formed in the exposed region 1c.

  In the mask pattern forming step, the three second mask portions 5 are formed so that the shape, size, distribution and density in the exposed region 1c are uniform. Thereby, three convex parts 7A, 7B, and 7C having the same shape corresponding to the second mask part 5 can be formed on the bottom part 6b of the through hole 6 by etching in the through hole forming process.

  The through wiring board 20 manufactured according to the present embodiment is provided with three protrusions 7A, 7B, and 7C protruding from the bottom surface 6b of the substrate 1 to the other surface 1b side of the through hole 6 and exposed in the through hole 6. Since the through wiring 9 is formed so as to cover the convex portions 7A, 7B, and 7C while being connected to the conductive film 3, the adhesion of the conductive film 3 to the through wiring 9 becomes higher than in the first embodiment. .

  In the first embodiment, a case where one convex portion 7 is formed on the bottom portion 6b of the through hole 6 is illustrated, and in the second embodiment, three convex portions 7A, 7B, 7C are formed on the bottom portion 6b of the through hole 6. However, the present invention is not limited to this. In the method for manufacturing a through wiring substrate according to the present invention, two or four or more convex portions may be formed at the bottom of the through hole as necessary.

  The method for manufacturing a through wiring board according to the present invention can be widely used for manufacturing electronic devices and the like.

DESCRIPTION OF SYMBOLS 1 ... Board | substrate, 1a ... One surface of a board | substrate, 1b ... The other surface of a board | substrate, 2 ... 1st insulating layer, 3 ... Conductive film, 4 ... 1st mask part, 5 ... 2nd mask part, 6 ... Through-hole, 7 ... Protrusions, 8 ... second insulating layer, 9 ... penetrating wiring, 10 ... penetrating wiring substrate, 20 ... penetrating wiring substrate.

Claims (2)

A first insulating layer forming step of forming a first insulating layer on one surface of the substrate;
A conductive film forming step of forming a conductive film on the first insulating layer;
A first mask portion is formed on the other surface of the substrate so that a part of the region is exposed and surrounds the second region, and a second space spaced from the first mask portion is formed in the exposed region. A mask pattern forming step for forming a mask portion;
By performing a first etching on the other surface side, the exposed region is dug down to form a through hole from the other surface toward the one surface, and the first insulating layer is exposed at the bottom of the through hole And a through hole forming step of forming a convex portion made of the substrate corresponding to the second mask portion at the bottom of the through hole,
A second insulating layer forming step of forming a second insulating layer on the inner wall and the other surface of the through hole;
Conductive film that exposes the conductive film in the through hole by removing the first insulating layer and the second insulating layer at the bottom of the through hole by performing second etching on the other surface side An exposure process;
A through-wiring forming step of disposing a conductive substance in the through-hole and forming a through-wiring connected to the conductive film;
A process for producing a through wiring board, comprising: The method for manufacturing a through wiring substrate according to claim 1, further comprising a seed layer forming step of forming a seed layer made of metal on a surface of the convex portion.

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