JP2021044374A - Through-hole electrode substrate, wiring substrate, and manufacturing method of wiring substrate - Google Patents

Abstract

To provide a through-hole electrode substrate that can suppress generation of voids in a resin part when the resin part is filled in a hollow part of the through-hole electrode.SOLUTION: The through-hole electrode substrate has a support substrate having a through-hole, a through-hole electrode disposed on a sidewall of the through-hole of the support substrate and provided with a hollow part in the through-hole, and a land part disposed continuously with the through-hole electrode around the hollow part on at least one side of the support substrate. The land part has a structure in which the thickness on the periphery side of the land part is smaller than the thickness on the hollow part side of the land part.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a through electrode substrate, a wiring board, and a method for manufacturing a wiring board.

In recent years, with the improvement of the performance of electronic devices, the development of three-dimensional mounting technology such as mounting a wiring board having an integrated circuit on another board has been promoted. In the three-dimensional mounting technology, a through electrode substrate having a through electrode is used. Such a through electrode substrate is used as an interposer, for example, and has a support substrate having a through hole, a through electrode arranged in the through hole, and a land portion continuously arranged with the through electrode. Can be mentioned. The land portion is a member used for connecting the wiring arranged on the through electrode substrate or the wiring arranged on another substrate to the through electrode.

In Patent Document 1, a first laminate including a substrate, a second wiring layer arranged on the first surface side of the substrate, and a first wiring layer and a second wiring layer arranged in a layer farther from the substrate than the first wiring layer. The body includes a third wiring layer arranged on the second surface side, which is a surface opposite to the first surface, and a fourth wiring layer arranged in a layer farther from the substrate than the third wiring layer. The second laminated body, the through hole penetrating the first laminated body, the substrate, and the second laminated body, and the second wiring layer and the fourth wiring layer arranged at least on the side wall of the through hole. An interposer including a conductive layer for connecting the above is disclosed.

JP-A-2017-73413

As one of the through electrode substrates having a through hole in the substrate as shown in Patent Document 1, a substrate having a through electrode arranged on the side wall portion of the through hole of the support substrate and having a hollow portion in the through hole can be mentioned. Can be done. When a through electrode substrate having the above-mentioned through electrode, which is also called a conformal via, has a space remaining in the through hole portion when used as a wiring substrate, for example, when a post-process such as further wiring formation is performed. There may be a problem that it is difficult to uniformly apply a material used in a post-process such as a resist, or a problem that the material leaks to the back surface side through a through hole.

To solve this problem, for example, it is common practice to close the through hole by filling the hollow portion of the through electrode with a resin portion.

As a method of filling the hollow portion of the through electrode with a resin portion, for example, a film containing a resin material containing the resin composition is arranged on at least one surface side of the through electrode substrate, and the resin composition is allowed to flow. Therefore, a method of filling the hollow portion of the through electrode with the resin composition and solidifying the resin composition can be mentioned. However, in the above method, a sufficient amount of the resin composition cannot be filled in the hollow portion of the through electrode, and voids (voids) remain in the resin portion filled in the hollow portion of the through electrode. There is. When the voids remain in this way, for example, the acid or alkali used in the subsequent process remains in the voids, resulting in deterioration such as electrode oxidation and deterioration of connection reliability, and through silicon via substrates. There is a concern that problems such as a decrease in the reliability of the front-back conduction via the above may occur.

The present disclosure has been made in view of the above circumstances, and an object of the present invention is to provide a through electrode substrate capable of suppressing the generation of voids in the resin portion when the hollow portion of the through electrode is filled with the resin portion. ..

In order to solve the above problems, the present disclosure comprises a support substrate having a through hole, a through electrode arranged on a side wall portion of the through hole of the support substrate and having a hollow portion in the through hole, and the support substrate. Around the hollow portion on at least one surface side of the above, a land portion is provided which is continuously arranged with the through electrode, and the land portion is larger than the thickness of the hollow portion side of the land portion. Provided is a through silicon via substrate having a structure in which the outer peripheral side of the land portion has a thin thickness.

According to the present disclosure, since the land portion has a structure in which the thickness on the outer peripheral side is thinner than the thickness on the central side, a film containing a resin material is used to heat and dissolve the resin composition in the resin layer of the film. In the step of filling the hollow portion of the through electrode with the resin composition, the molten resin composition can easily exceed the land portion, so that the through electrode substrate can suppress the generation of voids in the resin portion in the hollow portion. ..

In the above disclosure, the land portion has a step structure including a plurality of flat portions having different thicknesses, and the step structure is larger than the thickness of the flat portion located on the hollow portion side of the land portion. It is preferable that the flat portion located on the outer peripheral side of the land portion has a thin structure. For example, it is easy to form a land portion by using an etching method.

In the present disclosure, among others, the step structure includes two flat portions having different thicknesses, and the outer peripheral side of the land portion is larger than the thickness of the first flat portion located on the hollow portion side of the land portion. It is particularly preferable that the structure is such that the thickness of the second flat portion located in is thin. This is because it enables low-cost manufacturing.

Further, in the above disclosure, it is preferable that the difference in thickness between the thickness of the first flat portion and the thickness of the second flat portion is 0.5 μm or more and 1.5 μm or less. This is because when the difference in thickness is within a specific range, the resin composition can easily flow into the hollow portion of the through electrode, and the production becomes easy.

Further, in the above disclosure, the ratio of the width of the first flat portion to the width of the land portion is preferably 10% or more and 90% or less. This is because when the ratio of the widths is within a specific range, the resin composition can easily flow into the hollow portion of the through electrode.

The present disclosure provides a wiring board having the above-mentioned through electrode substrate and the resin portion filled in the hollow portion of the through electrode of the through electrode substrate.

The present disclosure is the method for manufacturing a wiring board described above, wherein the preparation step of preparing the penetrating electrode substrate and a resin containing a resin composition on at least one surface side of the penetrating electrode substrate on the land side. A wiring having a filling step of arranging a film containing a material and filling the hollow portion of the through electrode with the resin composition, and a solidification step of solidifying the filled resin composition to form a resin portion. A method for manufacturing a substrate is provided.

The through silicon via substrate of the present disclosure has an effect that the generation of voids in the resin portion can be suppressed when the hollow portion of the through electrode is filled with the resin portion.

It is the schematic cross-sectional view which illustrates the through silicon via substrate of this disclosure, and the schematic plan view of the land portion. It is a process drawing which illustrates the manufacturing method of the wiring board of this disclosure. It is the schematic cross-sectional view which illustrates the through silicon via substrate of this disclosure. It is a schematic plan view which illustrates the land part in this disclosure. It is the schematic plan view and schematic sectional view which illustrates the land part in this disclosure. It is schematic cross-sectional view which illustrates the wiring board of this disclosure. It is a process drawing which illustrates the manufacturing method of the wiring board of this disclosure. It is a process drawing which illustrates the manufacturing method of the conventional wiring board.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings and the like. However, the present disclosure can be implemented in many different embodiments and is not construed as limited to the description of the embodiments illustrated below. In addition, in order to clarify the explanation, the drawings may schematically represent the width, thickness, shape, etc. of each part as compared with the actual form, but this is just an example and the interpretation of the present disclosure is limited. It's not something to do. Further, in the present specification and each figure, the same elements as those described above with respect to the above-mentioned figures may be designated by the same reference numerals, and detailed description thereof may be omitted as appropriate.

In the present specification, when expressing the mode of arranging another member on a certain member, when simply expressing "above" or "below", unless otherwise specified, the member is in contact with the certain member. Including the case where another member is arranged directly above or directly below, and the case where another member is arranged above or below a certain member via another member.

Similarly, in the present specification, when the term "on the surface side of a certain member" is used, unless otherwise specified, another member may be placed directly in contact with the surface of a certain member, or a certain member may be placed. It shall include both the case where another member is arranged on the surface of the surface via another member.

The present disclosure is a technique relating to a through electrode substrate, a wiring board, and a method for manufacturing a wiring board. The details will be described below.

A. Through Silicon Via Substrate The through silicon via substrate of the present disclosure includes a support substrate having a through hole, a through electrode arranged on a side wall portion of the through hole of the support substrate and having a hollow portion in the through hole, and the support substrate. Around the hollow portion on at least one surface side, there is a land portion that is continuously arranged with the through electrode, and the land portion has a land portion that is larger than the thickness of the hollow portion side of the land portion. Has a structure in which the thickness on the outer peripheral side of the is thin.

The through silicon via substrate of the present disclosure will be described with reference to the drawings. FIG. 1A is a schematic cross-sectional view showing an example of the through silicon via substrate of the present disclosure, and FIG. 1B is a schematic plan view of a land portion shown in FIG. 1A. The through electrode substrates 10 shown in FIGS. 1 (a) and 1 (b) are arranged on a support substrate 1 having a through hole H and a side wall portion of the through hole H of the support substrate 1, and a hollow portion h is provided in the through hole H. It has a through electrode 2 provided and a land portion 3 arranged continuously with the through electrode 2 around a hollow portion h on at least one surface side of the support substrate 1. FIG. 1A shows an example in which the land portions 3 are arranged on both side surfaces of the support substrate 1.

As shown in FIGS. 1A and 1B, the land portion 3 is formed on the outer side of the through hole H, that is, the land portion 3 rather than the thickness of the central portion C side of the through hole H, that is, the hollow portion h side. It has a structure with a thin outer peripheral side. In FIGS. 1A and 1B, the land portion 3 has a stepped structure including two flat portions having different thicknesses, and the stepped structure is the first flat portion located on the central portion C side of the through hole H. An example is shown in which the thickness of the second flat portion 32 located on the outer peripheral side is thinner than the thickness of the portion 31.

According to the present disclosure, since the land portion has a structure in which the thickness on the outer peripheral side of the land portion is thinner than the thickness on the hollow portion side, when the hollow portion of the through electrode is filled with the resin portion, It can be a through electrode substrate capable of suppressing the generation of voids in the resin portion.

In the present specification, "filling the hollow portion of the through electrode with the resin portion" may be expressed as "filling the through hole with the resin portion".

Here, the effect of the through silicon via substrate of the present disclosure will be described with reference to the drawings. 2 (a) to 2 (c) are process diagrams showing an example of a method for manufacturing a wiring board using the through silicon via substrate of the present disclosure, and FIGS. 8 (a) to 8 (c) show conventional through silicon via substrates. It is a process drawing which shows an example of the manufacturing method of the wiring board used.

As shown in FIG. 8A, the conventional through electrode substrate 110 usually has a land portion 13 having a structure (flat structure) including one flat portion. Further, the land portion 13 needs to be formed to be relatively thick from the viewpoint of reinforcing the vicinity of the through hole H of the support substrate 11. As shown in FIG. 8B, a resin layer 51 is arranged on such a through electrode substrate 110, a pressure film 52 is airtightly arranged on the surface thereof, and a film 50 containing a resin material is arranged. Next, the film 50 containing the resin material is heated and the pressure inside the pressurizing film 52 is reduced. As a result, the resin layer 51 is pressurized at atmospheric pressure by the pressurizing film 52, and the heat-melted resin composition 5a in the resin layer 51 flows, so that the resin composition 5a flows into the hollow portion h. However, since the conventional through electrode substrate 110 has a land portion 13 having a relatively thick flat structure, the resin composition 5a flows into the hollow portion h due to the step between the land portion 13 and the support substrate 11. , And it may be difficult to fill the hollow portion h with a sufficient amount of the resin composition 5a. Therefore, as shown in FIG. 8C, void x may be generated in the resin portion 15 of the obtained wiring board 120.

On the other hand, as shown in FIG. 2A, the through silicon via substrate 10 of the present disclosure has a structure in which the land portion 3 has a thickness on the outer peripheral side of the land portion 3 that is thinner than the thickness on the hollow portion h side. Has. As shown in FIG. 2B, a dry film resist 51 is arranged on the surface of the through electrode substrate 10 on the land portion 3 side, and heating and pressurization are performed in the same manner as in the case of FIG. Since the land portion 3 in the present disclosure has a structure in which the thickness on the outer peripheral side is thinner than the thickness on the hollow portion h side, the molten resin composition 5a in the resin layer 51 crawls on the land portion 3. It can be easily lifted. As a result, the molten resin composition 5a in the resin layer 51 can be easily flowed into the hollow portion h, and a sufficient amount of the resin composition 5a can be filled into the hollow portion h. As a result, as shown in FIG. 2C, the wiring board 20 in which the generation of voids in the resin portion 5 is suppressed can be obtained.

Further, according to the present disclosure, since the generation of voids in the resin portion can be suppressed, even when a wiring board using a through electrode substrate is post-treated using an acid, an alkali or the like, the acid is also used. Since the residual amount in the voids of or alkali can be extremely reduced, deterioration of the electrode can be suppressed, and connection reliability and reliability of front-back conduction via the through silicon via substrate can be improved.

Hereinafter, each configuration of the through silicon via substrate of the present disclosure will be described.

1. 1. Land portion The land portion in the present disclosure is a member that is continuously arranged with a through electrode around a through hole on at least one surface side of a support substrate. Further, the land portion has a specific structure such that the thickness on the outer peripheral side is thinner than the thickness on the hollow portion side. The land portion having such a specific structure may be hereinafter referred to as a step land portion.

The step land portion in the present disclosure may be arranged on at least one surface side of the support substrate. For example, as shown in FIG. 1A, the step land portion 3 is located on both surface sides of the support substrate 1. It may be arranged, or as shown in FIG. 3, it may be arranged only on one surface side of the support substrate 1. When the step land portion 3 is arranged only on one surface side of the support substrate 1, a conventional land portion 4 having only one flat portion is usually arranged on the other surface side of the support substrate 1. ing. Whether the step land portion is arranged only on one surface side of the support substrate or on both surface sides is selected depending on the application of the support substrate and the like, but usually both of the support substrates are arranged. It is arranged on the surface side of.

The step land portion may be arranged around the hollow portion, for example, may be arranged in a part around the hollow portion, or may be arranged in the entire circumference of the hollow portion. The latter is more preferred. Since the strength of the portion near the through hole of the support substrate tends to be lower than that of other portions, by arranging the step land portion on the entire circumference of the through hole, the portion near the through hole of the support substrate is provided. This is because it can be satisfactorily reinforced. Further, since the step land portion is continuously arranged with the through electrode, the electrical connectivity between the step land portion and the through electrode should be improved by arranging the step land portion on the entire circumference of the through hole. Because it can be done.

The outer shape of the step land portion in a plan view can be appropriately selected depending on the application of the support substrate and the like, and is not particularly limited. The outer shape of the step land portion in a plan view may be, for example, the same shape as the shape of the through hole, or may be a different shape. Examples of the external shape of the step land portion in a plan view include a polygonal shape such as a circular shape, an elliptical shape, a rectangular shape, a pentagonal shape, and a hexagonal shape. Further, the outer shape of the step land portion in a plan view may have, for example, a shape obtained by cutting out a part of each of the above-mentioned shapes.

As described above, the step land portion has a specific structure in which the thickness on the outer peripheral side is thinner than the thickness on the hollow portion side of the step land portion. The step land portion is not particularly limited as long as it has the specific structure in at least a part thereof. For example, the step land portion may have the specific structure only in a part thereof. The above-mentioned specific structure may be provided in the entire step land portion. As an example in which the above-mentioned specific structure is provided only in a part of the step land portion, the structure of the step land portion 3 shown in FIGS. 4 (a) to 4 (c) described later can be mentioned. Further, as an example of having the above-mentioned specific structure in the entire step land portion, the structure of the step land portion 3 shown in FIG. 1 (b) can be mentioned.

In the present disclosure, it is particularly preferable that the entire step land portion has the above-mentioned specific structure. This is because the resin composition can be easily flowed into the hollow portion. In this case, it is particularly preferable that the step land portion is arranged on the entire circumference of the through hole. This is because the specific structure can be arranged on the entire circumference of the through hole, so that the strength can be improved and the resin composition can be more easily flowed into the through hole.

The structure of the step land portion is not particularly limited as long as it has a structure in which the thickness on the outer peripheral side is thinner than the thickness on the hollow portion side. It may be a tapered structure having a continuous inclination, but the former is preferable. For example, it is easy to form a desired step structure by an etching method.

The step structure in the step land portion has a structure in which the thickness of the flat portion located on the outer peripheral side of the step land portion is thinner than the thickness of the flat portion located on the hollow portion side of the step land portion. The number of flat portions constituting the stepped structure is not particularly limited as long as the thickness on the outer peripheral side can be made thinner than the thickness on the hollow portion side, and is usually two or more. Further, the number of flat portions may be, for example, 4 or less, or 3 or less. In the present disclosure, it is preferable that the number of flat portions is two. In other words, the step structure in the step land portion includes two flat portions having different thicknesses, and the second flat portion located on the outer side of the through hole is larger than the thickness of the first flat portion located on the central portion side of the through hole. It is preferable that the flat portion has a thin structure. This is because it is easy to form a desired stepped structure by an etching method at the time of manufacturing.

When the step land portion has a step structure including two flat portions, the arrangement of the first flat portion is not particularly limited as long as the step land portion having the above-mentioned specific structure can be arranged around the through hole. .. For example, as shown in FIGS. 1B and 4A, the first flat portion 31 may be arranged on the entire circumference of the through hole H. Further, as shown in FIGS. 4 (b) and 4 (c), the first flat portion 31 may be arranged in a part around the through hole H. Above all, it is more preferable that the first flat portion is arranged on the entire circumference of the through hole. This is because the portion near the through hole of the support substrate can be reinforced by the first flat portion. In addition, the electrical connectivity between the through electrode and the step land portion can be improved.

Further, the arrangement of the second flat portion is not particularly limited as long as the resin composition in a state where the resin layer of the film containing the resin material is melted can easily get over the step land portion. For example, as shown in FIG. 1B, the second flat portion 32 may be arranged on the entire circumference of the first flat portion 31. Further, as shown in FIGS. 4A to 4C, the second flat portion 32 may be arranged in a part around the first flat portion 31.
In the present disclosure, the second flat portion may be arranged on a part of the outer periphery of the first flat portion, but it is preferable that the second flat portion is arranged on the entire circumference of the first flat portion.

In the present disclosure, it is preferable that both the first flat portion and the second flat portion are arranged on the entire circumference of the through hole. Since the step land portion can have a step structure on the entire circumference of the through hole, for example, when the resin composition is filled in the through hole using a film containing a resin material, the step land portion covers the entire circumference of the through hole. This is because the resin composition can be easily flowed into the through hole.

4 (a) to 4 (c) are schematic plan views for explaining the step land portion. FIG. 4A shows an example in which the first flat portion 31 is arranged on the entire circumference of the through hole H, and the second flat portion 32 is arranged on a part around the through hole H. 4 (b) and 4 (c) show an example in which the first flat portion 31 and the second flat portion 32 are both arranged in a part around the through hole H. Further, FIG. 4 (c) shows an example of a structure in which a notch is provided in a part of the first flat portion 31 and the second flat portion 32 shown in FIG. 1 (b).

Further, for example, as shown in FIGS. 5A to 5D, the first flat portion 31 faces the surface opposite to the support substrate 1 side from the outer side of the through hole H toward the central portion C side. The groove portion g1 may be provided. This is because having the groove makes it easier for the resin composition to flow into the through hole. Further, in this case, as shown in FIG. 5A, the second flat portion does not have to have a groove portion, and as shown in FIG. 5B, the central portion C from the outer side of the through hole H. It may be provided with a groove g2 facing the side. In this case, for example, as shown in FIGS. 5 (c) and 5 (d), the groove g1 and the groove g2 may be continuously provided. Further, although not shown, a groove may be provided only in the second flat portion. 5 (a) and 5 (c) are schematic plan views illustrating a step land portion, and FIGS. 5 (b) and 5 (d) are sectional views taken along line AA of FIGS. 5 (a) and 5 (c). Is.

The external shapes of the first flat portion and the second flat portion in a plan view can be appropriately selected depending on the use of the through silicon via substrate, and are not particularly limited. The external shape of the first flat portion in plan view and the external shape of the second flat portion in plan view may have the same shape or different shapes, but the former is more preferable. This is because it is easy to adjust the dimensions of the first flat portion and the second flat portion in the step structure so that the resin layer of the film containing the resin material improves the fluidity of the melted resin composition.

Dimensions such as the width and thickness of the first flat portion and the second flat portion in the step land portion are appropriately adjusted according to the form of the support substrate such as the thickness of the support substrate and the size of the through hole, and in particular. The following dimensions can be given as an example, but not limited to.

In the present disclosure, the ratio of the width of the first flat portion to the width of the step land portion is, for example, preferably 10% or more, more preferably 30% or more, and more preferably 50% or more. More preferred. The ratio is, for example, preferably 90% or less, more preferably 80% or less, and even more preferably 70% or less. This is because when the above ratio is within the above-mentioned range, it is possible to facilitate the flow of the resin composition into the through hole while maintaining the strength of the step land portion.

The specific width of the step land portion is not particularly limited, but may be, for example, 5 μm or more, and may be 15 μm or more. Further, the width of the step land portion may be, for example, 80 μm or less, 60 μm or less, or 40 μm or less.

The width of the step land portion refers to the distance from the hollow portion side of the step land portion to the outer peripheral side, and the width of the first flat portion refers to the distance from the hollow portion side to the outer peripheral side of the first flat portion. The width of the second flat portion means the distance from the hollow portion side to the outer peripheral side of the second flat portion. As a specific example, in FIG. 1A, the width of the step land portion is the distance represented by w0, the width of the first flat portion is the distance represented by w1, and the width of the second flat portion is w2. It is the distance represented by.
In addition, w0, w1, and w2 when the outer shape of the step land portion in a plan view is not circular means the longest distance of each.

The thickness of the first flat portion and the thickness of the second flat portion are not particularly limited as long as the step land portion can have a desired step structure. The ratio of the thickness t2 of the second flat portion to the thickness t1 of the first flat portion is not particularly limited, but is, for example, 0.1 or more, 0.2 or more, and 0.3 or more. It may be. Further, the above ratio is, for example, 0.8 or less, may be 0.6 or less, or may be 0.5 or less.

The difference between the thickness of the first flat portion and the thickness of the second flat portion is not particularly limited, but is preferably 0.5 μm or more, for example. The difference in thickness may be, for example, 0.7 μm or more, or 0.9 μm or more. The difference in thickness is preferably 1.5 μm or less, for example. The difference in thickness may be, for example, 1.3 μm or less, or 1.1 μm or less. If the difference in thickness is too small, it becomes difficult to make it easy for the resin composition to sufficiently flow into the hollow portion when the resin composition is filled in the hollow portion using a film containing a resin material. Because there is a possibility. Further, if the difference in thickness is too large, it may be difficult to form a stepped structure.

The specific thickness of the first flat portion is not particularly limited, but may be, for example, 2 μm or more and 4 μm or more. The thickness of the first flat portion may be, for example, 10 μm or less, 8 μm or less, or 6 μm or less. The specific thickness of the second flat portion is not particularly limited, but may be, for example, 0.5 μm or more, 1 μm or more, or 2 μm or more. The thickness of the second flat portion is, for example, 5 μm or less, and may be 4 μm or less.
If the thickness of the first flat portion is too thin, there may be a problem in terms of the strength of the step land portion, and if it is too thick, the through silicon via substrate becomes thicker than necessary, and the elements to be used are made compact. This is because it hinders.

The thickness of the first flat portion refers to the distance from the surface of the support substrate on the step land side to the surface of the first flat portion opposite to the support substrate side, and is the thickness of the second flat portion. , The distance from the surface of the support substrate on the step land side to the surface of the second flat portion opposite to the support substrate side, which is the thickness of the first flat portion and the thickness of the second flat portion. The difference is the distance from the surface of the second flat portion opposite to the support substrate side to the surface of the first flat portion opposite to the support substrate side. As a specific example, in FIG. 1A, the thickness of the first flat portion is the distance represented by t1, the thickness of the second flat portion is the distance represented by t2, and the thickness of the first flat portion is The difference in thickness between the thickness and the thickness of the second flat portion is the distance represented by t3.

Here, the "thickness" of each member and each member portion means a thickness obtained by a general measuring method. As a method for measuring the thickness, a stylus-type method was used in which the thickness was calculated by tracing the surface with a stylus and detecting irregularities. Specifically, the thickness can be measured under the condition of a stylus pressure of 15 mg using a stylus type film thickness meter P-15 manufactured by KLA Tencor Co., Ltd. As the thickness, the average value of the thickness measurement results at a plurality of locations of the target member may be used.

The material used for the step land portion is not particularly limited as long as it is a conductive material, and a conductive material used for general wiring can be used, depending on the form and forming method of the wiring. It is selected as appropriate.

Specific examples of the material of the step land portion include metals such as copper, gold, silver, platinum, rhodium, tin, aluminum, nickel, and chromium, or alloys containing these metals.

In the above case, the step land portion may be a single layer or a multilayer in which a plurality of layers are laminated. The step land portion may have, for example, a seed layer arranged on the side wall portion of the through hole and a plating layer arranged on a surface of the seed layer opposite to the side wall side of the through hole. The material of the seed layer can be appropriately selected from the materials used for the seed layer in a general plating method. The material of the seed layer is preferably a conductive material having adhesion to the support substrate, and examples thereof include titanium, molybdenum, tungsten, tantalum, nickel, chromium, aluminum, compounds thereof, and alloys thereof. be able to. When the plating layer contains copper, the material of the seed layer is preferably a material capable of suppressing the diffusion of copper into the support substrate, and examples thereof include titanium nitride, molybdenum nitride, and tantalum nitride. be able to. The material of the plating layer is preferably a conductive material having adhesion to the seed layer, and examples thereof include the above-mentioned material of the step land portion.

The method for forming the step land portion is not particularly limited as long as it can be formed continuously with the through electrode and can form the step land portion having a specific structure. For example, a method of etching a conductive material layer may be used. Can be mentioned. As an example, when the step land portion has a step structure including two flat portions having different thicknesses, the following method can be mentioned. First, a conductive material layer is formed on at least one surface side of the support substrate and on the side wall portion of the through hole. Next, the photoresist is arranged on the conductive material layer so that the portion corresponding to the first flat portion of the through electrode and the step land portion is covered and the portion corresponding to the second flat portion is exposed. Next, the second flat portion is formed by etching the conductive material layer exposed from the photoresist to reduce the thickness. By the above steps, a step land portion can be formed. Examples of the method for forming the conductive material layer include a plating method.

2. Through Silicon Via The through electrode is a member that is arranged on the side wall of the through hole and has a hollow portion at the center of the through hole. Through silicon vias in the present disclosure are also referred to as conformal vias.

The through electrode is not particularly limited as long as it is arranged on the side wall of at least a part of the through hole and is continuously arranged with the land portion described above, but it is preferably arranged on the entire side wall portion of the through hole. This is because the electrical connectivity between the front and back surfaces of the through electrode substrate can be improved.

The thickness of the through electrode can be appropriately selected depending on the form of the support substrate, the material used for the through electrode, the method of forming the through electrode, and the like, and is not particularly limited. For example, the thickness may be the same as the thickness of the step land portion described in the section “1. Land portion” described above.

Since the material and the forming method used for the through electrode can be the same as those described in the above-mentioned section “1. Land portion”, the description thereof is omitted here.

3. 3. Support substrate The support substrate is a substrate having through holes, and is a substrate that supports the above-mentioned land portion and through electrode.

The support substrate has through holes. The plan-view shape of the through hole can be appropriately selected depending on the application of the through electrode substrate and the like, and is not particularly limited. Examples of the plan view shape of the through hole include a circular shape and an elliptical shape. The size of the through hole can be appropriately selected depending on the application of the through electrode substrate, and is not particularly limited, but may be, for example, 10 μm or more and 200 μm or less, or 20 μm or more and 100 μm or less.

Examples of the method for forming the through hole include etching such as plasma etching and wet etching, laser irradiation, and mechanical processing methods such as sandblasting and ultrasonic drilling. In the present disclosure, a support substrate having through holes formed by itself may be used, or a substrate having through holes may be purchased and used in advance.

The material used for the support substrate can be the same as the material of the substrate used for a general wiring board, and is not particularly limited. Examples of the support substrate include a resin substrate, a glass substrate, a silicon substrate, a quartz substrate, a sapphire substrate, and the like. When the support substrate is a glass substrate, examples of the glass used include soda lime glass, non-alkali glass, and quartz glass. When the support substrate is a resin substrate, the resin used may be, for example, polyimide. The support substrate preferably has heat resistance.

The thickness of the support substrate can be appropriately selected depending on the application of the through silicon via substrate and the like, and is not particularly limited. For example, it is preferably 10 μm or more, more preferably 100 μm or more, and 300 μm or more. It is more preferable to have. The thickness of the support substrate is, for example, preferably 2000 μm or less, more preferably 1000 μm or less, and further preferably 700 μm or less.

4. Other Structures The through electrode substrate of the present disclosure is not particularly limited as long as it has the above-mentioned support substrate, through electrode, and land portion, and other necessary configurations can be appropriately selected and added. Other configurations include, for example, wiring and the like.

5. Other methods for manufacturing the through electrode substrate of the present disclosure include, for example, a method of preparing a support substrate having a through hole and forming a through electrode and a land portion.

The through silicon via substrate of the present disclosure can be used in "B. Wiring substrate" described later.

B. Wiring board The wiring board of the present disclosure includes a through electrode substrate described in the section of "A. Through electrode substrate" described above, and a resin portion filled in the hollow portion of the through electrode.

The wiring board of the present disclosure will be described with reference to the drawings. FIG. 6 is a schematic cross-sectional view showing an example of the wiring board of the present disclosure. The wiring board 20 shown in FIG. 6 has a through electrode substrate 10 and a resin portion 5 filled in the hollow portion h of the through electrode 2. Since each configuration of the through silicon via 10 can be the same as that described with reference to FIGS. 1 (a) and 1 (b), the description thereof will be omitted here.

According to the present disclosure, by having the through silicon via substrate described above, it is possible to obtain a wiring substrate in which the generation of voids in the resin portion is suppressed. Hereinafter, each configuration of the wiring board of the present disclosure will be described.

1. 1. Through Silicon Via Substrate The through electrode substrate in the present disclosure can be the same as the content described in the above-mentioned "A. Through Silicon Via Substrate", and thus the description thereof is omitted here.

2. Resin part The resin part in the present disclosure is a member filled in the hollow part of the through electrode of the through electrode substrate.

The degree of filling of the resin portion can be appropriately selected depending on the intended use of the wiring board, and is not particularly limited, but it is preferable that the entire hollow portion is filled with the resin portion.

Examples of the material of the resin portion include epoxy resin, acrylic resin, polyimide, polyamide, polyester and the like.
In the present disclosure, the resin composition used for the dry film resist is particularly preferable.

The method for forming the resin portion is not particularly limited as long as the through holes in the through electrode substrate can be filled with the resin portion, but for example, a method using a film containing a resin material is preferable. Details of the method for forming the resin portion using the film containing the resin material will be described in the section “C. Method for manufacturing a wiring board” described later.

3. 3. Other Configurations The wiring substrate of the present disclosure is not particularly limited as long as it has a through electrode substrate and a resin portion, and other necessary configurations can be appropriately selected and added. Other configurations include, for example, a build-up layer. When the build-up layer has a land portion for interlayer connection, the land portion for interlayer connection may have a specific structure described in the above-mentioned section "A. Through Silicon Via 1. Land portion". It does not have to be.

The method for manufacturing the wiring board is not particularly limited as long as the wiring board having the through electrode board and the resin portion described above can be manufactured, but it is the method described in the section "C. Manufacturing method for wiring board" described later. Is preferable.

The wiring board of the present disclosure can be used, for example, in a semiconductor device. In addition, applications of semiconductor devices that use wiring boards include, for example, mobile terminals (mobile phones, smartphones, notebook personal computers, etc.), information processing devices (desktop personal computers, servers, car navigation systems, etc.), home appliances, and the like. Uses can be mentioned.

C. Method for Manufacturing Wiring Board The method for manufacturing the wiring board of the present disclosure is the method for manufacturing the above-mentioned "B. Wiring board", which is a preparatory step for preparing the penetrating electrode board and at least one of the penetrating electrode board. A filling step of filling the hollow portion of the through electrode with the resin composition by arranging a film containing a resin material on the surface side of the step land portion and allowing the resin composition to flow, and filling. It has a solidification step of solidifying the above resin composition to form a resin portion.

The manufacturing method of the wiring board of the present disclosure will be described with reference to the drawings. 2 (a) to 2 (c) are process diagrams showing an example of the method for manufacturing the wiring board of the present disclosure. In the method for manufacturing the wiring board of the present disclosure, first, as shown in FIG. 2A, the through silicon via board 10 is prepared (preparation step). Next, the resin layer 51 is arranged on the surface side of at least one step land portion 3 side of the through electrode substrate 10. Next, the film 50 containing the resin material is arranged by arranging the pressure film 52 for pressing the DFR 51 at atmospheric pressure so as to cover the entire resin layer 51. Then, the whole is heated to such an extent that the resin layer 51 can flow, the pressure inside the pressure film 52 is reduced, and the resin layer 51 is pressed by atmospheric pressure. As a result, the resin composition in which the resin layer is melted flows into the hollow portion h of the through electrode 2 and fills the resin composition 5a (filling step). Next, the filled resin composition 5a is solidified to form the resin portion 5 as shown in FIG. 2C (solidification step). The wiring board 20 can be manufactured by the above steps.

7 (a) to 7 (c) are process diagrams showing another example of the method for manufacturing the wiring board of the present disclosure. As shown in FIG. 7A, when the through electrode substrate 10 has the step land portion 3 on only one surface side, the DFR 51 is arranged on the step land portion 3 side and the resin composition 5a is allowed to flow. , The hollow portion h of the through electrode 2 can be filled with the resin composition 5a. The points not explained in FIGS. 7 (a) to 7 (c) can be the same as the contents of the drawings already described, and thus the description thereof will be omitted here.

According to the present disclosure, by using the through silicon via substrate described above, it is possible to manufacture a wiring substrate by suppressing the generation of voids in the resin portion.

Hereinafter, each step in the method for manufacturing the wiring board of the present disclosure will be described.

1. 1. Preparation Step The preparation step in the present disclosure is a step of preparing a through electrode substrate. The through silicon via substrate prepared in the preparation step can be the same as the content described in the above-mentioned section “A. Through silicon via substrate”, and thus the description thereof is omitted here.

2. Filling Step In the filling step in the present disclosure, a film containing a resin material containing a resin composition is placed on the surface side of at least one land portion of the through electrode substrate, and the resin composition is allowed to flow to flow the through electrode. This is a step of filling the hollow portion of the resin composition.

In the filling step, a film containing a resin material containing a resin composition is arranged on the surface side of the through silicon via substrate on the step land side. When the through silicon via substrate has step lands on both sides thereof, a film containing a resin material may be arranged on both side surfaces of the through silicon via substrate, or a film containing a resin material may be arranged on one surface side. It may be, but the former is more preferable. This is because it is easy to fill the hollow portion of the through electrode with the resin composition.

A film containing a resin material typically has a film layer and a resin layer arranged on one surface side of the film layer and containing a resin composition. In the present disclosure, since it is preferable to fill the resin composition by pressurization, the film layer is preferably, for example, a pressurizing film having durability against pressurization during filling. Further, the pressurizing film is more preferably a film having heat resistance to heat treatment described later. As the film layer, a general film can be appropriately selected and used. The resin layer (resist layer) is not particularly limited as long as it contains a resin composition that can be filled in the through holes. Examples of the resin composition used for the resin layer include a resin composition capable of obtaining the resin used for the resin portion described in the above-mentioned "B. Wiring substrate" section.

Further, as a method of arranging the film containing the resin material, for example, the film layer (pressurizing film) and the resin layer may be arranged separately on the through electrode substrate, or for example, the film layer and the resin layer may be arranged in advance. A film containing a resin material may be formed by laminating, and the film containing the resin material may be arranged on a through electrode substrate.

In the filling step, the resin composition is filled in the hollow portion of the through electrode by flowing the resin composition. The filling method of the resin composition is not particularly limited as long as the resin can be flowed through the hollow portion of the through electrode. For example, the DFR is heated so that the fluidity of the resin composition becomes high, and the resin composition is formed. It is preferably a method of filling an object. This is because the resin composition can easily flow into the hollow portion of the through electrode.

The heating temperature can be appropriately adjusted according to the type of the resin composition and the like, and is not particularly limited, but may be, for example, 50 ° C. or higher and 150 ° C. or lower.

Further, in the present disclosure, the film containing the resin material may be heat-treated before the film containing the resin material is arranged on the through electrode substrate, and the film containing the resin material arranged on the through electrode substrate may be subjected to heat treatment. Heat treatment may be performed. Since the heat treatment method can be the same as the heat treatment method for a general dry film resist, the description thereof is omitted here.

Further, as a method for filling the resin composition, for example, a method for filling the resin composition by pressure-treating a laminate in which a film containing a resin material and a through silicon via substrate are laminated is also preferable. By performing the pressure treatment, it is possible to facilitate the flow of the resin composition into the hollow portion of the through electrode. Examples of the pressurizing treatment include a vacuuming treatment. The evacuation process can be performed using, for example, a laminating apparatus. The conditions for the evacuation treatment are not particularly limited, and can be appropriately adjusted according to the type of the resin composition, the thickness of the support substrate, and the like.

As a method for filling the resin composition, it is particularly preferable that the resin composition is filled by performing both the heat treatment and the pressure treatment described above. This is because the hollow portion of the through electrode can be satisfactorily filled with the resin composition.

3. 3. Solidification Step The solidification step in the present disclosure is a step of solidifying the filled resin composition to form a resin portion.

The method for solidifying the resin composition is appropriately selected according to the type of the resin composition, and is not particularly limited. For example, when the resin composition is a thermosetting resin composition, a method of curing the resin composition by performing a heat treatment can be mentioned. The heat treatment temperature can be appropriately selected depending on the type of the resin composition. When the resin composition is an ionizing radiation curable resin composition, a method of curing the resin composition by performing an ionizing radiation irradiation treatment can be mentioned. Here, "ionizing radiation" means an electromagnetic wave or a charged particle beam having an energy quantum capable of polymerizing or cross-linking a molecule, and usually, ultraviolet rays or electron beams are used, but other X-rays, Electromagnetic waves such as γ-rays and charged particle beams such as α-rays and ion rays can also be used. The irradiation conditions of ionizing radiation can be appropriately selected according to the type of resin composition.

Since the resin portion formed in the solidification step can be the same as the content described in the above-mentioned section “B. Wiring board 2. Resin portion”, the description thereof is omitted here.

4. Others The method for manufacturing the wiring board of the present disclosure is not particularly limited as long as it has the above-mentioned filling step, and other necessary steps can be appropriately selected and added.

Since the wiring board manufactured by the manufacturing method of the present disclosure can be the same as the content described in the above-mentioned section “B. Wiring board”, the description thereof is omitted here.

The present disclosure is not limited to the above embodiment. The above embodiment is an example, and any object having substantially the same structure as the technical idea described in the claims of the present disclosure and exhibiting the same effect and effect is the present invention. Included in the technical scope of the disclosure.

(Examples 1 to 3)
(Manufacturing of through silicon via substrate)
The through silicon via substrates shown in FIGS. 1 (a) and 1 (b) were produced.
A glass substrate (thickness 400 μm) having a through hole (hole diameter: 130 μm) was prepared. Copper sputtering treatment was performed on the front and back surfaces of the glass substrate and the inner wall of the through hole, and a resist pattern was formed on the dry film resist (Sanfort AQ4038 manufactured by Asahi Kasei Electronic Co., Ltd.). The resist pattern covered the through holes and was arranged in the regions of the first flat portion and the second flat portion shown in FIGS. 1 (a) and 1 (b). The copper layer in the exposed portion was removed with an etching solution for copper (AD-331, manufactured by Meltec). The resist pattern was peeled off with an aqueous sodium hydroxide solution at 50 ° C. and removed.

Next, a dry film resist was used to cover the through holes and the region of the first flat portion, and a resist pattern was formed so that the second flat portion was exposed. Next, the copper layer in the exposed portion was thinned with an etching solution for copper (AD-331, manufactured by Meltec). Next, the resist pattern was peeled off with an aqueous sodium hydroxide solution at 50 ° C. and removed. Through the above steps, a through electrode substrate was obtained. The width w1 and thickness t1 of the first flat portion and the width w2 and thickness t2 of the second flat portion of the obtained through silicon via substrate were set to the values shown in Table 1.

(Manufacturing of wiring board)
On the front and back surfaces of the obtained through electrode substrate, a film in which 20 um of polyimide resin was formed on a 100 um-thick PET film was placed as a film containing a resin material.
Next, the through silicon via substrate on which the film containing the resin material is arranged is heated at 80 ° C. to impart fluidity to the resin composition of the film containing the resin material, and then evacuated (500 hPa). The resin composition was flowed and filled in the through holes. Then, the film containing the resin material was removed. The through silicon via substrate filled with the resin composition was heat-treated at 230 ° C. for 30 minutes in a nitrogen atmosphere to solidify the resin composition and form a resin portion. A wiring board was obtained by the above procedure.

[Comparison example]
A wiring board was obtained in the same manner as in Examples 1 to 3 except that a through electrode substrate having a flat land portion shown in FIG. 8A was produced. The plan view shape of the land portion is a shape that surrounds the entire circumference of the through hole as in FIG. 1 (b).

A glass substrate (thickness 400 μm) having a through hole (hole diameter: 130 μm) was prepared. Copper sputtering treatment was performed on the front and back surfaces of the glass substrate and the inner wall of the through hole, and a resist pattern was formed on the dry film resist (Sanfort AQ4038 manufactured by Asahi Kasei Electronic Co., Ltd.). The resist pattern covered the through hole and was arranged in the area of the land portion shown in FIGS. 1 (a) and 1 (b). The copper layer in the exposed portion was removed with an etching solution for copper (AD-331, manufactured by Meltec). Through the above procedure, a through electrode substrate was obtained. The width and thickness of the land portion were set to the values of w1 and t1 in Table 1.

[Evaluation]
Water was poured on one surface side (front side) of the obtained wiring board, and vacuum adsorption was performed. If water did not wrap around the other surface side (back side) of the wiring board, it was judged that there was no void, and if water wraps around, it was judged that there was a void. The results are shown in Table 1.

From the results of Examples 1 to 3 and Comparative Example, it was confirmed that the occurrence of voids can be suppressed by having the step land portion.

1 ... Support substrate 2 ... Through silicon via 3 ... Land part (step land part)
31 ... 1st flat part 32 ... 2nd flat part 5 ... Resin part 5a ... Resin composition C ... Central part H ... Through hole h ... Hollow part 10 ... Through electrode board 20 ... Wiring board 50 ... Film containing resin material

Claims (7)

A support substrate with through holes and
A through electrode arranged on the side wall of the through hole of the support substrate and having a hollow portion in the through hole,
A land portion that is continuously arranged with the through electrode is provided around the hollow portion on at least one surface side of the support substrate.
The land portion is a through electrode substrate having a structure in which the thickness of the outer peripheral side of the land portion is thinner than the thickness of the hollow portion side of the land portion. The land portion has a step structure including a plurality of flat portions having different thicknesses, and the step structure is the outer circumference of the land portion rather than the thickness of the flat portion located on the hollow portion side of the land portion. The through electrode substrate according to claim 1, which has a structure in which the flat portion located on the side has a thin thickness. The step structure includes two flat portions having different thicknesses, and a second flat portion located on the outer peripheral side of the land portion with respect to the thickness of the first flat portion located on the hollow portion side of the land portion. The through electrode substrate according to claim 2, which has a structure having a thin thickness. The through electrode substrate according to claim 3, wherein the difference between the thickness of the first flat portion and the thickness of the second flat portion is 0.5 μm or more and 1.5 μm or less. The through electrode substrate according to claim 3 or 4, wherein the ratio of the width of the first flat portion to the width of the land portion is 10% or more and 90% or less. The through silicon via substrate according to any one of claims 1 to 5.
A resin portion filled in the hollow portion of the through electrode and a resin portion
Has a wiring board. The method for manufacturing a wiring board according to claim 6.
The preparatory step for preparing the through silicon via substrate and
A film containing a resin material containing a resin composition is placed on at least one surface side of the through electrode substrate on the land side, and the resin composition is allowed to flow in the hollow portion of the through electrode. The filling step of filling the resin composition and
A method for manufacturing a wiring board, comprising a solidification step of solidifying the filled resin composition to form the resin portion.

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