Through-hole electrode substrate

Abstract

To provide a through-hole electrode substrate with high reliability, capable of suppressing an increase in transmission loss and meeting the demand for high density and miniaturization of the through-hole electrode.SOLUTION: A through-hole electrode substrate includes a substrate including a first surface and a second surface and provided with a through-hole, and a through electrode located in the through-hole. The through-hole has a narrow section having a minimum aperture. An aperture p in the narrow section is 10 μm or more and 50 μm or less; an aperture D1 in the first surface is 60 μm or less; and an aperture D2 in the second surface is 60 μm or less. The through-hole has an adhesion layer and a conductive layer. The thickness t of the conductive layer is 0.5 μm or more and 10 μm or less. The volume of the conductive layer inside the through-hole is 5% or more and 50% or less of the volume of the through-hole. The coefficient of thermal expansion of the substrate is 2 ppm / K or more and 8 ppm / K or less. The dielectric tangent of the substrate at a frequency of 20 GHz is 0.0003 or more and 0.005 or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a through electrode substrate having a through electrode. [Background technology]

[0002] A through electrode substrate includes a substrate including a first surface and a second surface, a plurality of through holes provided in the substrate, and through electrodes provided inside the through holes so as to extend from the first surface side to the second surface side of the substrate, as disclosed in Patent Document 1, for example. Such through electrode substrates have conventionally been used for a variety of purposes, and are mounted in electronic devices such as mobile phones. The through electrodes of such through electrode substrates are generally classified into a filled type (also called a filled via) in which a conductive material (typically copper) fills the entire through hole, and an unfilled type (also called a conformal via) in which a conductive material layer is provided on the side of the through hole, making it hollow.

[0003] As a method for forming a through electrode, for example, a method is known in which a seed layer is formed on the side surface of a through hole, and a plating layer is formed on the seed layer by electrolytic plating. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-163986 Summary of the Invention [Problem to be solved by the invention]

[0005] Through-hole electrode substrates are implemented in a variety of electronic devices, from smartphones to large-scale servers. However, as the clock speeds of electronic devices increase and communication frequencies become higher, the increase in transmission loss during high-speed, high-frequency operation has become a significant problem.

[0006] Furthermore, the integration of LSI devices mounted on through-hole electrode substrates is becoming increasingly high, and this trend is driving demands for higher density and finer through-hole electrodes in the through-hole electrode substrates. Furthermore, as through-hole electrode substrates become more complex due to higher density, they are also required to be highly reliable.

[0007] One test for this high reliability is a heat cycle test. In a heat cycle test, for example, a through hole electrode substrate is heated from -55°C to 125°C over one hour, held at 125°C for one hour, and then cooled from 125°C to -55°C over one hour. In some tests, this heat cycle is repeated 1,000 times on a through hole electrode substrate. However, there is a problem in that cracks and gaps occur in the through hole electrode substrate due to the thermal stress of the heat cycle test described above.

[0008] An object of the present disclosure is to provide a through electrode substrate that can effectively solve the above-mentioned problems. [Means for solving the problem]

[0009] A through electrode substrate according to an embodiment of the present disclosure includes a substrate including a first surface and a second surface opposite to the first surface and having a through hole provided therein, and a through electrode located in the through hole of the substrate, wherein the through hole has a narrowed portion between the first surface and the second surface, where the hole diameter is smallest, and the narrowed portion has a hole diameter p of 10 μm or more and 50 μm or less, a hole diameter D1 in the first surface is 60 μm or less, and a hole diameter D2 in the second surface is 60 μm or less, and the through electrode is provided on a side surface of the through hole. The through electrode has, in this order from the side of the through hole toward the center of the through hole, an adhesive layer and a conductive layer, the conductive layer has a thickness t in the range of 0.5 μm to 10 μm and is smaller than 1 / 2 of the hole diameter p, the volume of the conductive layer inside the through hole is 5% to 50% of the volume of the through hole, the thermal expansion coefficient of the substrate is 2 ppm / K to 8 ppm / K, and the dielectric loss tangent of the substrate at a frequency of 20 GHz is 0.0003 to 0.005.

[0010] In the through hole electrode substrate according to the embodiment of the present disclosure, the adhesion layer may contain any one of titanium (Ti), titanium nitride (TiN), and zinc oxide (ZnO).

[0011] In the through hole electrode substrate according to the embodiment of the present disclosure, the conductive layer may contain copper (Cu).

[0012] In one embodiment of the through-hole electrode substrate of the present disclosure, the narrowed portion of the through-hole is located at a distance d from either the first surface or the second surface of the substrate toward the other surface, and the distance d may be 20 μm or more and less than 1 / 2 of the thickness g of the substrate.

[0013] In the through hole electrode substrate according to an embodiment of the present disclosure, the thickness g of the substrate may be 200 μm or more and 500 μm or less.

[0014] In one embodiment of the through electrode substrate of the present disclosure, on one of a pair of side surfaces that constitute the through hole in a cross-sectional view, the angle θ1 formed by a line connecting the edge of the narrowing portion to the edge of the opening of the through hole on the first surface side of the substrate and the normal to the first surface of the substrate may be 1.25° or more and 6.25° or less, and the angle θ2 formed by a line connecting the edge of the narrowing portion to the edge of the opening of the through hole on the second surface side of the substrate and the normal to the second surface of the substrate may be 1.25° or more and 6.25° or less.

[0015] In one embodiment of the through electrode substrate of the present disclosure, a filling resin is located on the through electrode from the side of the through hole toward the center of the through hole, filling the through hole, and the dielectric loss tangent of the filling resin at a frequency of 20 GHz may be 0.003 or more and 0.02 or less.

[0016] In a through-hole electrode substrate according to one embodiment of the present disclosure, the filled resin may contain a filled resin filler, which has a thermogravimetric change of 3% by weight or less at 250°C and a thermal expansion coefficient of 0.5 ppm / K or more and 8 ppm / K or less, and the filled resin filler may be contained in an amount of 30% by volume or more and 80% by volume or less of the filled resin.

[0017] In one embodiment of the through electrode substrate of the present disclosure, an insulating resin layer may be provided on the first surface side of the substrate, and the dielectric loss tangent of the insulating resin constituting the insulating resin layer at a frequency of 20 GHz may be 0.001 or more and 0.01 or less.

[0018] In a through electrode substrate according to one embodiment of the present disclosure, the insulating resin may contain an insulating resin filler, which has a thermogravimetric change of 3% by weight or less at 250°C and a thermal expansion coefficient of 0.5 ppm / K or more and 8 ppm / K or less, and the insulating resin filler may be contained in an amount greater than 0% by volume and less than 30% by volume of the insulating resin.

[0019] In one embodiment of the through electrode substrate of the present disclosure, a via hole penetrating the insulating resin layer may be provided at a position that does not overlap with the through hole when viewed from the normal direction of the first surface of the substrate, and a conductive via filled with a conductive material may be provided inside the via hole.

[0020] In one embodiment of the through electrode substrate of the present disclosure, a via hole penetrating the insulating resin layer may be provided at a position overlapping the through hole when viewed from the normal direction of the first surface of the substrate, and a conductive via filled with a conductive material may be provided inside the via hole.

[0021] In one embodiment of the through electrode substrate of the present disclosure, the insulating resin layer may include a first insulating resin layer in contact with the substrate and a second insulating resin layer stacked on top of the first insulating resin layer, a first via hole penetrating the first insulating resin layer at a position overlapping the through hole when viewed from the normal direction of the first surface of the substrate, a conductive via filled with a conductive material inside the first via hole, a second via hole penetrating the second insulating resin layer at a position overlapping the conductive via when viewed from the normal direction of the first surface of the substrate, and a side conductive layer made of a conductive material on the inside side of the second via hole.

[0022] In one embodiment of the through electrode substrate of the present disclosure, the insulating resin layer may include a first insulating resin layer in contact with the substrate and a second insulating resin layer stacked on top of the first insulating resin layer, a first via hole penetrating the first insulating resin layer at a position overlapping the through hole when viewed from the normal direction of the first surface of the substrate, a first side conductive layer made of a conductive material on the inner side of the first via hole, a second via hole penetrating the second insulating resin layer at a position overlapping the first via hole when viewed from the normal direction of the first surface of the substrate, and a second side conductive layer made of a conductive material on the inner side of the second via hole. [Effects of the Invention]

[0023] According to the present disclosure, it is possible to provide a highly reliable through electrode substrate that can suppress an increase in transmission loss during high-speed, high-frequency driving, meet the demand for higher density and finer through electrodes, and provide a highly reliable through electrode substrate. [Brief explanation of the drawings]

[0024] [Figure 1] 1 is a cross-sectional view showing an example of a through-hole electrode substrate according to the present disclosure; [Figure 2] FIG. 2 is a cross-sectional view showing a through hole of the through electrode substrate shown in FIG. [Figure 3] FIG. 1 is a cross-sectional view showing another example of a through-hole electrode substrate according to the present disclosure. [Figure 4] FIG. 1 is a cross-sectional view showing another example of a through-hole electrode substrate according to the present disclosure. [Figure 5] FIG. 1 is a cross-sectional view showing another example of a through-hole electrode substrate according to the present disclosure. [Figure 6] FIG. 1 is a cross-sectional view showing another example of a through-hole electrode substrate according to the present disclosure. [Figure 7] FIG. 1 is a cross-sectional view showing another example of a through-hole electrode substrate according to the present disclosure. [Figure 8] 1 is a diagram showing an example of a manufacturing process for a through-hole electrode substrate; [Figure 9] FIG. 9 is a diagram showing an example of a manufacturing process of a through hole electrode substrate following FIG. 8. [Figure 10] FIG. 10 is a diagram showing an example of a manufacturing process of a through hole electrode substrate following FIG. 9. [Figure 11] 11 is a diagram showing an example of a manufacturing process of a through hole electrode substrate following FIG. 10. [Figure 12] 12 is a diagram showing an example of a manufacturing process of a through hole electrode substrate following FIG. 11. [Figure 13] 13 is a diagram showing an example of a manufacturing process of the through electrode substrate following FIG. 12. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, a through-hole electrode substrate and a manufacturing method thereof according to an embodiment of the present disclosure will be described in detail with reference to the drawings. Note that the embodiments described below are examples of embodiments of the present disclosure, and the present disclosure should not be interpreted as being limited to these embodiments. Furthermore, terms used in this specification that specify shapes, geometric conditions, and their degrees, such as "parallel" and "orthogonal," as well as values ​​of length and angle, are not limited to their strict meanings but are interpreted to include the range within which similar functions can be expected. In addition, in the drawings referred to in this embodiment, identical or similar symbols are used for identical parts or parts having similar functions, and repeated explanations may be omitted. Furthermore, the dimensional ratios in the drawings may differ from the actual ratios for convenience of explanation, and some components may be omitted from the drawings.

[0026] (First embodiment) <Through-electrode substrate> Hereinafter, embodiments of the present disclosure will be described. First, the configuration of a through hole electrode substrate 1 according to one embodiment of the present disclosure will be described with reference to Figures 1 and 2. Here, Figure 1 is a cross-sectional view showing an example of a first embodiment of a through hole electrode substrate of the present disclosure, and Figure 2 is a cross-sectional view showing a through hole of the through hole electrode substrate shown in Figure 1.

[0027] 1, the through electrode substrate 1 includes a substrate 10 having a first surface 11 and a second surface 12 located on the opposite side of the first surface 11 and having a through hole 13 formed therein, and a through electrode 20 located in the through hole 13 of the substrate 10. The through electrode 20 is provided on the side surface of the through hole 13 so that the through hole 13 is hollow. In other words, the through electrode substrate 1 has the form of a conformal via.

[0028] Here, in FIG. 1, as an example, an enlarged cross-sectional view of one through electrode (through electrode 20) that the through electrode substrate 1 has is shown, but typically, the through electrode substrate 1 is provided with a plurality of through electrodes. Each component of the through hole electrode substrate 1 will be described below.

[0029] (substrate) As shown in FIGS. 1 and 2, the substrate 10 includes a first surface 11 and a second surface 12 located opposite the first surface 11. The substrate 10 contains an inorganic material with a certain level of insulating properties. Since this allows for small expansion or contraction of the substrate 10 in response to temperature changes, it is preferable that the thermal expansion coefficient of the substrate 10 is small. For example, the thermal expansion coefficient of the substrate 10 is preferably 2 ppm / K or more and 8 ppm / K or less. Furthermore, in order to minimize transmission loss at high frequencies in the through-hole electrode substrate, it is preferable that the dielectric loss tangent of the substrate 10 is small. For example, the dielectric loss tangent of the substrate 10 at a frequency of 20 GHz is preferably 0.0003 or more and 0.005 or less.

[0030] For example, the substrate 10 is a glass substrate or a quartz substrate. Examples of glass used for the substrate 10 include alkali-free glass.

[0031] Alkali-free glass is glass that does not contain alkali components such as sodium or potassium. Alkali-free glass contains, for example, boric acid instead of alkali components. Alkali-free glass also contains alkaline earth metal oxides such as calcium oxide and barium oxide. Examples of alkali-free glass include EN-A1 manufactured by Asahi Glass Co., Ltd. and Eagle XG manufactured by Corning Incorporated.

[0032] The thickness g of the substrate 10 is preferably 200 μm or more and 500 μm or less. The manufacturing process of the through hole electrode substrate includes a polishing step, typically a CMP (Chemical Mechanical Polishing) step, but if the thickness g of the substrate 10 is less than 200 μm, the thin thickness results in insufficient strength and may result in breakage during the polishing step.

[0033] In addition, the manufacturing process for a through electrode substrate includes a step of forming a seed layer to form a thick through electrode by electroplating. However, if the thickness g of the substrate 10 is greater than 500 μm, the depth of the through hole will be greater than the opening, and if the seed layer is formed by sputtering, it may not be possible to form a seed layer of the required thickness deep inside the through hole, and the through electrode formed by subsequent electroplating may not be of the desired thickness.

[0034] On the other hand, when the thickness g of the substrate 10 is 200 μm or more and 500 μm or less, the above problems do not occur and the through hole electrode substrate 1 can be obtained satisfactorily.

[0035] (Through hole) 2, the substrate 10 is provided with a through hole 13 extending from the first surface 11 to the second surface 12. The through hole 13 formed in the substrate 10 has a narrowed portion 14 at a distance d from the first surface 11 toward the second surface 12 of the substrate 10, where the diameter of the through hole 13 is minimum.

[0036] In other words, when viewed in cross section, the side of the through hole 13 formed in the substrate 10 has a tapered first surface side portion 15 that tapers from the first surface 11 side of the substrate 10 toward the narrowed portion 14, and a tapered second surface side portion 16 that tapers from the second surface 12 side of the substrate 10 toward the narrowed portion 14.

[0037] Since the shape of the openings of through hole 13 on the first surface 11 side and second surface 12 side in a plan view is usually circular, through hole 13 can also be expressed as a shape in which two truncated cones with the same smaller-area bottom surface (upper base) are joined together at their upper bases. In this case, the joined upper base portion corresponds to narrowed portion 14.

[0038] The tapered shape mentioned above means a "taper" shape when viewed from a broad perspective, and does not necessarily mean that the side surfaces of each part in a cross-sectional view of through hole 13 as shown in FIG. 2 extend linearly. Even if the side surfaces extend in a curved shape, include a curved portion in part, or have both a linear portion and a curved portion, these shapes are included in the concept of a tapered shape as long as they are "tapered" when viewed from a broad perspective.

[0039] In the through hole electrode substrate of the present disclosure, the position of narrowed portion 14 of through hole 13 is preferably 20 μm or more from either first surface 11 or second surface 12 of substrate 10 toward the other surface, and is preferably ½ or less of the thickness g of substrate 10. For example, in the example shown in FIG. 2 , narrowed portion 14 of through hole 13 is located at a distance d from first surface 11 toward second surface 12 of substrate 10, and the magnitude of this distance d is preferably 20 μm or more and ½ or less of the thickness g of substrate 10.

[0040] As described above, the manufacturing process of the through-hole electrode substrate includes a polishing process, typically a CMP (Chemical Mechanical Polishing) process. However, if the distance d is smaller than 20 μm, the edge of the opening of the through-hole 13 on the first surface 11 side is likely to chip during this polishing process. On the other hand, if the distance d is 20 μm or more, the above problems can be prevented from occurring.

[0041] Regarding the maximum value of the distance d, the relationship between the first surface 11 and the second surface 12 of the substrate 10 is such that when either the front or back surface of the substrate 10 (for example, the front surface) is defined as the first surface 11, the opposite surface (the back surface) is defined as the second surface 12. Therefore, the maximum value of the distance d is sufficient to be half the distance from the first surface 11 to the second surface 12. In other words, the maximum value of the distance d is half the thickness g of the substrate 10.

[0042] For example, if the position of the narrowed portion 14 exceeds half of the thickness g of the substrate 10 from one of the surfaces (e.g., the front surface) of the substrate 10 toward the opposite surface (the back surface), the distance from the opposite surface (the back surface) to the position of the narrowed portion 14 will be less than half of the thickness g of the substrate 10.

[0043] Furthermore, in through-hole 13 shown in FIG. 2, the hole diameter p of through-hole 13 at narrowed portion 14 is preferably 10 μm or more and 50 μm or less.

[0044] The diameter D1 of the opening of through-hole 13 on the first surface 11 side of substrate 10 is larger than the diameter p of narrowed portion 14, and the diameter D2 of the opening of through-hole 13 on the second surface 12 side of substrate 10 is also larger than the diameter p of narrowed portion 14. In order to meet the demand for higher density and finer through electrodes, it is preferable that the diameter D1 is 60 μm or less, and the diameter D2 is also 60 μm or less.

[0045] The through hole 13 is formed by laser processing or the like, but if the hole diameter p of the through hole 13 at the narrowed portion 14 is smaller than 10 μm, the narrowed portion 14 becomes too narrow, making it difficult to form the through hole 13 in the desired shape.

[0046] Furthermore, if the hole diameter p of the through hole 13 in the narrowed portion 14 is larger than 50 μm, it becomes difficult to form the hole diameter D1 and hole diameter D2 of the opening of the through hole 13 to be 60 μm or less while maintaining the angle of the side surface of the through hole 13 (for example, the angle θ shown in Figure 2) at a predetermined size or greater.

[0047] On the other hand, when the hole diameter p of the through-hole 13 in the narrowed portion 14 is 10 μm or more and 50 μm or less, the above-mentioned problems do not occur, and the through-hole electrode substrate 1 can be obtained satisfactorily.

[0048] Furthermore, in the through hole 13 shown in Figure 2, when viewed in cross section, it is preferable that the angle θ1 formed by a line connecting the edge (Rp) of the narrowing portion 14 and the edge (R1) of the opening of the through hole 13 on one of the pair of side surfaces constituting the through hole 13, and the normal N1 to the first surface 11 of the substrate 10, is 1.25° or more and 6.25° or less, and it is preferable that the angle θ2 formed by a line connecting the edge (Rp) of the narrowing portion 14 and the edge (R2) of the opening of the through hole 13 on the second surface 12 of the substrate 10, and the normal N2 to the first surface 11 of the substrate 10, is 1.25° or more and 6.25° or less.

[0049] As described above, the manufacturing process for a through-hole electrode substrate includes a step of forming a seed layer to form a thick through-hole electrode by electroplating. However, if the above angles θ1 and θ2 are smaller than 1.25°, the slope of the side surface of the through-hole is close to vertical, and if the seed layer is formed by sputtering, it may not be possible to form a seed layer of the required thickness deep inside the through-hole, and the through-hole formed by subsequent electroplating may not be of the desired thickness.

[0050] Furthermore, if the angle θ1 is greater than 6.25°, the opening of the through hole 13 on the first surface 11 side becomes too large, which may make it unsuitable for high-density mounting. Similarly, if the angle θ2 is greater than 6.25°, the opening of the through hole 13 on the second surface 12 side becomes too large, which may make it unsuitable for high-density mounting.

[0051] On the other hand, when the angle θ1 and the angle θ2 are 1.25° or more and 6.25° or less, the above-mentioned problems do not occur, and a good through hole electrode substrate 1 can be obtained.

[0052] (Through electrode) The through electrode 20 is a conductive member and is located in the through hole 13 in the through electrode substrate 1, as shown in Fig. 1. More specifically, as shown in Fig. 1, the through electrode 20 is provided on the side surface of the through hole 13 so that the through hole 13 is hollow. In other words, the through electrode substrate 1 has the form of a conformal via. Here, the volume of the conductive layer 23 inside the through hole 13 is preferably 5% to 50% of the volume of the through hole 13.

[0053] If the volume of the conductive layer 23 inside the through hole 13 is smaller than 5% of the volume of the through hole 13, the electrical resistance of the through electrode 20 becomes too high, resulting in a large transmission loss.

[0054] Furthermore, if the volume of the conductive layer 23 inside the through hole 13 is larger than 50% of the volume of the through hole 13, stress may occur between the through electrode 20 and the material constituting the substrate 10 in an environment where low and high temperatures are repeated, such as in a heat cycle test, and cracks may occur in the substrate 10.

[0055] On the other hand, if the volume of the conductive layer 23 inside the through hole 13 is 5% or more and 50% or less of the volume of the through hole 13, the above-mentioned problems do not occur and a good through electrode substrate 1 can be obtained.

[0056] Furthermore, the through electrode 20 is usually composed of multiple layers. For example, in the example shown in Fig. 1, the through electrode 20 has an adhesion layer 21 on the side surface of the through hole 13, a seed layer 22 on the adhesion layer 21, and a conductive layer 23 on the seed layer 22. In other words, the through electrode 20 has, in order from the side surface of the through hole 13 toward the center of the through hole 13, the adhesion layer 21, the seed layer 22, and the conductive layer 23.

[0057] The adhesion layer 21 is provided between the substrate 10 and the seed layer 22, and has the effect of increasing the adhesion between the substrate 10 and the seed layer 22. The adhesion layer 21 contains one of titanium (Ti), titanium nitride (TiN), and zinc oxide (ZnO), and is formed by sputter ion deposition, PVD, or a sol-gel method. The thickness of the adhesion layer 21 is, for example, 20 nm or more and 200 nm or less.

[0058] The seed layer 22 is a conductive layer that serves as a base for growing the conductive layer 23 by depositing metal ions in a plating solution during an electrolytic plating process to form the conductive layer 23. The seed layer 22 can be made of a conductive material such as copper (Cu), titanium (Ti), or a combination thereof. The material of the seed layer 22 may be the same as or different from the material of the conductive layer 23. The thickness of the seed layer 22 is, for example, 50 nm or more and 1000 nm or less. The seed layer 22 can be formed by, for example, sputtering, vapor deposition, or a combination of sputtering and vapor deposition.

[0059] The conductive layer 23 is a conductive layer formed by electrolytic plating on the seed layer 22. Examples of materials that can be used to form the conductive layer 23 include metals such as copper (Cu), gold (Au), silver (Ag), platinum (Pt), rhodium (Rh), tin (Sn), aluminum (Al), nickel (Ni), and chromium (Cr), alloys using these metals, and laminates of these metals.

[0060] The thickness t of the conductive layer 23 is smaller than half the hole diameter p of the narrowed portion 14 of the through hole 13 shown in Fig. 2, and is preferably 0.5 µm or more and 10 µm or less. In the through electrode 20 shown in Fig. 1, the thickness of the adhesion layer 21 and the thickness of the seed layer 22 are usually smaller than the thickness of the conductive layer 23, and therefore, the thickness t may be considered to be approximately the combined thickness of the adhesion layer 21, the seed layer 22, and the conductive layer 23.

[0061] The through electrodes 20 are electrically connected to the elements mounted on the through electrode substrate, but if the thickness t is less than 0.5 μm, the electrical resistance increases, resulting in a problem of degraded electrical characteristics. Furthermore, if the thickness t is excessively small, it becomes difficult to form the through electrodes 20 with a uniform thickness. Furthermore, if the thickness t is greater than 10 μm, cracks are likely to occur in the through electrode substrate due to the thermal stress of the heat cycle test.

[0062] On the other hand, when the thickness t is 0.5 μm or more and 10 μm or less, the above problems do not occur and a good through hole electrode substrate 1 can be obtained.

[0063] (Second embodiment) 3 is a cross-sectional view showing an example of a second embodiment of the through hole electrode substrate of the present disclosure. Note that components similar to those of the above-described through hole electrode substrate 1 are given the same reference numerals and repeated description thereof will be omitted.

[0064] The through hole electrode substrate of the present disclosure may have a form including a filling resin 31, for example, like the through hole electrode substrate 2 illustrated in FIG.

[0065] 1, the through electrode substrate 2 shown in Fig. 3 has a filling resin 31 that is located on the through electrode 20 from the side surface of the through hole 13 toward the center of the through hole 13 and fills the through hole 13. Furthermore, the through electrode substrate 2 illustrated in Fig. 3 also has a filling resin 31 on the second surface 12 side of the substrate 10.

[0066] In the through electrode substrate 2 shown in FIG. 3, since the filled resin 31 is included, it is possible to achieve the effects of alleviating stress and preventing foreign matter from entering the inside of the through hole 13.

[0067] As a method for forming the filling resin 31, for example, a method can be mentioned in which a film made of a material that constitutes the filling resin 31 is attached to the second surface 12 side of the substrate 10 of the through electrode substrate 1 shown in Figure 1, and the filling resin 31 is embedded in the through hole 13 by a method such as vacuum lamination.

[0068] (filled resin) The filling resin 31 contains an organic material and has insulating properties. The filling resin 31 may also contain a photosensitive material. Examples of organic materials that can be used for the filling resin 31 include polyimide, epoxy, benzocyclobutene resin, polyamide, phenolic resin, silicone resin, fluororesin, liquid crystal polymer, polyamideimide, polybenzoxazole, cyanate resin, aramid, polyolefin, polyester, BT resin, FR-4, FR-5, polyacetal, polybutylene terephthalate, syndiotactic polystyrene, polyphenylene sulfide, polyether ether ketone, polyether nitrile, polycarbonate, polyphenylene ether polysulfone, polyethersulfone, polyarylate, and polyetherimide. The above resins may be used alone or in combination of two or more.

[0069] Filled resin 31 may contain a filler (filled resin filler) such as glass, talc, mica, silica, or alumina. To prevent cracks from occurring in filled resin 31 even after a heat cycle test, the filled resin filler preferably has a thermogravimetric change of 3% by weight or less at 250°C and a thermal expansion coefficient of 0.5 ppm / K or more and 8 ppm / K or less. Furthermore, the filled resin filler is preferably contained in an amount of 30% by volume or more and 80% by volume or less of filled resin 31.

[0070] 3, the dielectric loss tangent of the filling resin 31 at a frequency of 20 GHz is preferably 0.003 or more and 0.02 or less. This is because by setting the dielectric loss tangent at high frequencies of the filling resin 31 provided in the through holes 13 to a value within the above-mentioned predetermined range, the transmission loss of the through electrode substrate 2 at high frequencies can be reduced.

[0071] (Third embodiment) 4 is a cross-sectional view showing an example of a third embodiment of the through electrode substrate of the present disclosure. Note that components similar to those of the above-described through electrode substrate 1 and through electrode substrate 2 are given the same reference numerals, and repeated description thereof will be omitted.

[0072] 4 has an insulating resin layer 50 in addition to the configuration of the through hole electrode substrate 2 shown in FIG. More specifically, the through electrode substrate 3 shown in Fig. 4 has an insulating resin layer 50 on the first surface 11 side of the substrate 10 in addition to the configuration of the through electrode substrate 2 shown in Fig. 3. Furthermore, the through electrode substrate 3 illustrated in Fig. 4 has a via hole penetrating the insulating resin layer 50, and a conductive via 61 filled with a conductive material inside the via hole. Here, the through electrode substrate 3 has the conductive via 61 at a position that does not overlap with the through hole 13 when viewed from the normal direction of the first surface 11 of the substrate 10. The conductive via 61 is electrically connected to the through electrode 20.

[0073] 4, a wiring layer can be further laminated on the insulating resin layer 50. Furthermore, the resin constituting the insulating resin layer 50 can be a resin having a smaller dielectric tangent than the resin constituting the filling resin 31, i.e., a resin with better transmission characteristics.

[0074] Furthermore, in the through electrode substrate 3 shown in FIG. 4, the diameter of the conductive vias 61 can be made smaller than the opening diameter of the through holes 13 (more specifically, the hole diameter D1 of the opening of the through holes 13 on the first surface 11 side of the substrate 10 shown in FIG. 2), which is advantageous for achieving high density. For example, if a photosensitive resin is used as the resin constituting the insulating resin layer 50, via holes with a diameter of 2 μm to 30 μm can be formed by photolithography, and conductive vias 61 of the same size (2 μm to 30 μm diameter) can be formed. Furthermore, if a UV laser is used, via holes with a diameter of 5 μm to 30 μm can be formed, and conductive vias 61 of the same size (5 μm to 30 μm diameter) can be formed.

[0075] (insulating resin layer) The insulating resin layer 50 contains an organic material and has insulating properties. The insulating resin layer 50 may also contain a photosensitive material. Examples of organic materials that can be used for the insulating resin layer 50 include polyimide, epoxy, benzocyclobutene resin, polyamide, phenolic resin, silicone resin, fluororesin, liquid crystal polymer, polyamideimide, polybenzoxazole, cyanate resin, aramid, polyolefin, polyester, BT resin, FR-4, FR-5, polyacetal, polybutylene terephthalate, syndiotactic polystyrene, polyphenylene sulfide, polyether ether ketone, polyether nitrile, polycarbonate, polyphenylene ether polysulfone, polyethersulfone, polyarylate, and polyetherimide. The above resins may be used alone or in combination of two or more.

[0076] The insulating resin layer 50 may contain a filler (insulating resin filler) such as glass, talc, mica, silica, or alumina. To prevent cracks from occurring in the insulating resin layer 50 even after a heat cycle test, the insulating resin filler preferably has a thermogravimetric change of 3% by weight or less at 250°C and a thermal expansion coefficient of 0.5 ppm / K or more and 8 ppm / K or less. The insulating resin filler is preferably contained in the insulating resin layer 50 in an amount of more than 0% by volume and 30% by volume or less.

[0077] 4, the dielectric loss tangent of the insulating resin constituting the insulating resin layer 50 at a frequency of 20 GHz is preferably 0.001 or more and 0.01 or less. This is because by setting the dielectric loss tangent of the insulating resin layer 50 at high frequencies within the above-mentioned predetermined range, the transmission loss of the through hole electrode substrate 3 at high frequencies can be reduced.

[0078] (Conductive vias) The conductive via 61 is made of a conductive material and is provided inside a via hole that penetrates the insulating resin layer 50. Here, in the through electrode substrate 3 shown in FIG. 4, the conductive via 61 is provided at a position that does not overlap with the through hole 13 when viewed from the normal direction of the first surface 11 of the substrate 10. The conductive via 61 is electrically connected to the through electrode 20.

[0079] The conductive vias 61 can be formed by electrolytic plating, similar to the conductive layer 23 that constitutes the through electrode 20. The conductive material that constitutes the conductive vias 61 can be metals such as copper (Cu), gold (Au), silver (Ag), platinum (Pt), rhodium (Rh), tin (Sn), aluminum (Al), nickel (Ni), chromium (Cr), or alloys using these metals, or laminates of these metals.

[0080] (Fourth embodiment) 5 is a cross-sectional view showing an example of a fourth embodiment of the through hole electrode substrate of the present disclosure. Note that the same components as those in the above-described through hole electrode substrates 1 to 3 are given the same reference numerals, and repeated description thereof will be omitted.

[0081] The through electrode substrate 4 shown in Figure 5 has an insulating resin layer 50, similar to the form of the through electrode substrate 3 shown in Figure 4, but the conductive via 62 of the through electrode substrate 4 is located at a position that overlaps with the through hole 13 when viewed from the normal direction of the first surface 11 of the substrate 10. It should be noted that "overlapping" with the through-hole 13 includes a form in which the through-hole 13 is encompassed, and a form in which the through-hole 13 is partially overlapped.

[0082] 4, the conductive via 62 of the through electrode substrate 4 shown in Fig. 5 is also made of a conductive material, and is provided inside a via hole that penetrates the insulating resin layer 50. Examples of the conductive material that constitutes the conductive via 62 include the same conductive materials as those that constitute the conductive via 61 described above. The conductive via 62 is also electrically connected to the through electrode 20.

[0083] 5, the through electrode substrate 4 can electrically connect the wiring and electrodes provided on the upper and lower sides of the insulating resin layer 50 at the positions of the through holes 13 when viewed from the normal direction of the first surface 11 of the substrate 10. This facilitates the design of stacked wiring. Furthermore, by connecting the conductive vias 62 to the through electrodes 20 at the edges of the openings of the through holes 13 (more specifically, the openings of the through holes 13 on the first surface 11 side of the substrate 10 shown in FIG. 2), the diameter of the conductive vias 62 can be kept approximately the same as the opening diameter of the through holes 13, allowing for higher density.

[0084] In the through electrode substrate 4 shown in Figure 5, as in the through electrode substrate 3 shown in Figure 4, a photosensitive resin is used as the resin that constitutes the insulating resin layer 50, and via holes can be formed using photolithography or a UV laser. 5, the opening of the through hole 13 on the first surface 11 side of the substrate 10 is sealed with the conductive material that constitutes the conductive via 62, but the opening of the through hole 13 on the second surface 12 side of the substrate 10 is not sealed and the resin that constitutes the filling resin 31 is exposed. Therefore, in the through electrode substrate 4, gas in the resin that constitutes the filling resin 31 can be released from the opening of the through hole 13 on the second surface 12 side of the substrate 10.

[0085] (Fifth embodiment) 6 is a cross-sectional view showing an example of a through hole electrode substrate according to a fifth embodiment of the present disclosure. Note that the same components as those in the through hole electrode substrates 1 to 4 described above are denoted by the same reference numerals, and repeated description thereof will be omitted.

[0086] 3, the through hole electrode substrate 5 shown in FIG. 6 has, on the first surface 11 side of the substrate 10, a first insulating resin layer 51, and a conductive via 63 filled with a conductive material inside a via hole (first via hole) penetrating the first insulating resin layer 51. Furthermore, a second insulating resin layer 52 is provided on the upper side of the first insulating resin layer 51, and a side conductive layer 70 made of a conductive material is provided on the side surface of a via hole (second via hole) penetrating the second insulating resin layer 52. A filler 80 is provided on the upper side of the side conductive layer 70 (more specifically, on the upper side of the side conductive layer 70 in the direction from the side surface of the second via hole toward the center of the second via hole).

[0087] The conductive vias 63 of the through electrode substrate 5 are provided at positions overlapping the through holes 13 when viewed from the normal direction of the first surface 11 of the substrate 10. The via holes (second via holes) that penetrate the second insulating resin layer 52 on which the side conductive layer 70 is provided are provided at positions overlapping the conductive vias 63 when viewed from the normal direction of the first surface 11 of the substrate 10. The side conductive layer 70 is electrically connected to the conductive via 63 , and the conductive via 63 is electrically connected to the through electrode 20 .

[0088] Because of this configuration, in the through electrode substrate 5 shown in Figure 6, even if the number of stacked insulating resin layers increases, the wiring and electrodes provided on the upper and lower sides of each insulating resin layer can be electrically connected at the position where the through hole 13 is provided, when viewed from the normal direction of the first surface 11 of the substrate 10, making it easier to design the stacked wiring. Furthermore, by connecting the conductive via 63 to the through electrode 20 at the edge of the opening of the through hole 13 (more specifically, the opening of the through hole 13 on the first surface 11 side of the substrate 10 shown in FIG. 2), the diameter of the conductive via 63 can be kept approximately the same as the opening diameter of the through hole 13, making it possible to achieve higher density. The outer diameter of the side conductive layer 70 can be made approximately the same as the diameter of the conductive via 63, or can be made smaller than the opening diameter of the through hole 13.

[0089] The conductive via 63 and side conductive layer 70 of the through electrode substrate 5 shown in Figure 6 are also made of a conductive material, similar to the conductive via 62 of the through electrode substrate 4 shown in Figure 5, and examples of the conductive material include the same conductive material as that of the conductive via 61 described above. The thickness of the side conductive layer 70 can be set to, for example, 1 μm or more and 10 μm or less.

[0090] 6 includes a filler 80 containing an organic material and having insulating properties. The filler 80 may contain a photosensitive material. The material constituting the filler 80 may be the same as the material constituting the insulating resin layer 50 described above.

[0091] Filler 80 may contain a filler such as glass, talc, mica, silica, or alumina. To prevent cracks from occurring in filler 80 even after a heat cycle test, the filler preferably has a thermogravimetric change of 3% or less by weight at 250°C and a thermal expansion coefficient of 0.5 ppm / K or more and 8 ppm / K or less. Furthermore, the filler is preferably contained in filler 80 in an amount of more than 0% by volume and 30% by volume or less.

[0092] 6, the dielectric loss tangent of filler 80 at a frequency of 20 GHz is preferably 0.001 or more and 0.01 or less. This is because by setting the dielectric loss tangent of filler 80 at high frequencies to a small value within a predetermined range, the transmission loss of through hole electrode substrate 5 at high frequencies can be reduced.

[0093] The first insulating resin layer 51 and the conductive vias 63 can be formed by the same method as that for the through electrode substrate 4 shown in FIG. Via holes can be formed in the second insulating resin layer 52 by photolithography or UV laser using a photosensitive resin, in the same manner as in the first insulating resin layer 51. In this case, by forming the via holes in the second insulating resin layer 52 in a ring shape, a cylindrical portion of the second insulating resin layer 52 can be left as the filler 80 shown in FIG. As a method for forming the side conductive layer 70, for example, a seed layer is formed by sputtering in the via hole of the second insulating resin layer 52 provided as described above, and then the side conductive layer 70 is formed by electrolytic plating. Since the via hole of the first insulating resin layer 51 is filled with the conductive via 63, the occurrence of disconnection due to a step can be suppressed in the formation of the seed layer. 5, in the through electrode substrate 5 shown in Fig. 6, the openings of the through holes 13 on the first surface 11 of the substrate 10 are sealed with the conductive material that constitutes the conductive vias 63, but the openings of the through holes 13 on the second surface 12 of the substrate 10 are configured so that the resin that constitutes the filling resin 31 is exposed without being sealed with the conductive material. Therefore, in the through electrode substrate 5 as well, gas in the resin that constitutes the filling resin 31 can be released from the openings of the through holes 13 on the second surface 12 of the substrate 10.

[0094] (Sixth embodiment) 7 is a cross-sectional view showing an example of a through hole electrode substrate according to a sixth embodiment of the present disclosure. Note that the same components as those in the through hole electrode substrates 1 to 5 described above are denoted by the same reference numerals, and repeated description thereof will be omitted.

[0095] 3, the through hole electrode substrate 6 shown in Fig. 7 has a first insulating resin layer 51 on the first surface 11 of the substrate 10, and a first side surface conductive layer 71 made of a conductive material on the side surface of a via hole (first via hole) that penetrates the first insulating resin layer 51. A first filler 81 is provided on the upper side of the first side surface conductive layer 71 (more specifically, on the upper side of the first side surface conductive layer 71 in the direction from the side surface of the first via hole toward the center of the first via hole). Furthermore, a second insulating resin layer 52 is provided on the upper side of the first insulating resin layer 51, and a second side surface conductive layer 72 made of a conductive material is provided on the side surface of a via hole (second via hole) penetrating the second insulating resin layer 52. A second filler 82 is provided on the upper side of the second side surface conductive layer 72 (more specifically, on the upper side of the second side surface conductive layer 72 in the direction from the side surface of the second via hole toward the center of the second via hole).

[0096] The first via hole (i.e., the via hole penetrating the first insulating resin layer 51) in which the first side surface conductive layer 71 of the through electrode substrate 6 is provided is located at a position overlapping the through hole 13 when viewed from the normal direction of the first surface 11 of the substrate 10. The second via hole (i.e., the via hole penetrating the second insulating resin layer 52) in which the second side surface conductive layer 72 is provided is located at a position overlapping the first via hole when viewed from the normal direction of the first surface 11 of the substrate 10. The second side surface conductive layer 72 is electrically connected to the first side surface conductive layer 71 , and the first side surface conductive layer 71 is electrically connected to the through electrode 20 .

[0097] Because of this configuration, even in the through electrode substrate 6 shown in Figure 7, even if the number of stacked insulating resin layers increases, the wiring and electrodes provided on the upper and lower sides of each insulating resin layer can be electrically connected at the position where the through hole 13 is provided, when viewed from the normal direction of the first surface 11 of the substrate 10, making it easier to design the stacked wiring. Furthermore, by connecting the first side surface conductive layer 71 to the through electrode 20 at the edge of the opening of the through hole 13 (more specifically, the opening of the through hole 13 on the first surface 11 side of the substrate 10 shown in FIG. 2 ), the outer diameter of the first side surface conductive layer 71 can be reduced to approximately the same size as the opening diameter of the through hole 13. Similarly, by connecting the second side surface conductive layer 72 to the first side surface conductive layer 71, the outer diameter of the second side surface conductive layer 72 can be reduced to approximately the same size as the outer diameter of the first side surface conductive layer 71. In other words, the outer diameter of the second side surface conductive layer 72 can be reduced to approximately the same size as the opening diameter of the through hole 13. Therefore, even if the number of laminated insulating resin layers increases, higher density can be achieved. Here, also in the through electrode substrate 6 shown in FIG. 7, the opening of the through hole 13 on the second surface 12 side of the substrate 10 is configured so that the resin constituting the filling resin 31 is exposed without being sealed with a conductive material. Furthermore, in the through electrode substrate 6, the opening of the through hole 13 on the first surface 11 side of the substrate 10 is also configured so that the resin (the resin constituting the filling resin 31, the resin constituting the first filling material 81, and the resin constituting the second filling material 82) is exposed without being sealed with a conductive material. Therefore, in the through electrode substrate 6, the gas in the resin constituting the filling resin 31 can be The gas can be released from both the opening of the through-hole 13 on the first surface 11 side of the substrate 10 and the opening of the through-hole 13 on the second surface 12 side of the substrate 10, allowing the gas to be released more effectively.

[0098] The first side conductive layer 71 of the through hole electrode substrate 6 shown in Fig. 7 is also made of a conductive material, similar to the side conductive layer 70 of the through hole electrode substrate 5 shown in Fig. 6, and examples of the conductive material include the same conductive materials as those constituting the conductive via 61 described above. Similarly, the second side conductive layer 72 is also made of a conductive material, and examples of the conductive material include the same conductive materials as those constituting the conductive via 61 described above. The thickness of the first side surface conductive layer 71 and the second side surface conductive layer 72 can be set to, for example, 1 μm or more and 10 μm or less.

[0099] 7 includes a first filler 81 and a second filler 82 containing an organic material and having insulating properties. The first filler 81 and the second filler 82 may contain a photosensitive material. The material constituting the first filler 81 and the second filler 82 may be the same as the material constituting the insulating resin layer 50 described above.

[0100] The first filler 81 and the second filler 82 may contain a filler such as glass, talc, mica, silica, or alumina. To prevent cracks from occurring in the first filler 81 and the second filler 82 even after a heat cycle test, the filler preferably has a thermogravimetric change of 3% or less by weight at 250°C and a thermal expansion coefficient of 0.5 ppm / K or more and 8 ppm / K or less. The filler is preferably contained in the first filler 81 and the second filler 82 in an amount of more than 0% by volume and not more than 30% by volume.

[0101] 7, the dielectric loss tangents of the first filler 81 and the second filler 82 at a frequency of 20 GHz are preferably 0.001 or more and 0.01 or less. This is because by setting the dielectric loss tangents of the first filler 81 and the second filler 82 at high frequencies to small values ​​within a predetermined range, the transmission loss of the through hole electrode substrate 6 at high frequencies can be reduced.

[0102] The first insulating resin layer 51 and the first side conductive layer 71 of the through hole electrode substrate 6 shown in Fig. 7 can be formed by the same method as the method for forming the second insulating resin layer 52 and the side conductive layer 70 of the through hole electrode substrate 5 shown in Fig. 6. By forming the via hole in the first insulating resin layer 51 in a ring shape, it is also possible to leave the cylindrical first insulating resin layer 51 as the first filler 81 shown in Fig. 7. The second insulating resin layer 52 and the second side surface conductive layer 72 of the through electrode substrate 6 can also be formed in the same manner as the first insulating resin layer 51 and the first side surface conductive layer 71. By forming the via hole provided in the second insulating resin layer 52 in a ring shape, it is possible to leave a cylindrical second insulating resin layer 52 as the second filler 82 shown in FIG.

[0103] <Method of manufacturing a through electrode substrate> Next, an example of a method for manufacturing the through hole electrode substrate of the present disclosure will be described. Here, a method for manufacturing the through hole electrode substrate 1 shown in FIG. 1 will be described with reference to FIGS.

[0104] (Manufacturing of substrates with through holes) First, a substrate including a first surface 11 and a second surface 12 located on the opposite side of the first surface 11 is prepared, and a laser is irradiated from each side of the first surface 11 and the second surface 12 to produce a substrate 10 having a through hole 13 of the desired shape, as shown in Figure 8. For example, by irradiating a laser from the side of the first surface 11, a portion of the through hole 13 extending from the first surface 11 of the substrate 10 to the narrowed portion 14 can be formed, and by irradiating a laser from the side of the second surface 12, a portion of the through hole 13 extending from the second surface 12 of the substrate 10 to the narrowed portion 14 can be formed.

[0105] Lasers that can be used for laser processing include excimer lasers, Nd:YAG lasers, femtosecond lasers, etc. When using an Nd:YAG laser, it is possible to use a fundamental wave with a wavelength of 1064 nm, a second harmonic with a wavelength of 532 nm, or a third harmonic with a wavelength of 355 nm.

[0106] In addition, as another manufacturing method, first, a resist layer having an opening at a position corresponding to the through hole 13 is provided on the first surface 11 and the second surface 12 of the substrate, and then the through hole 13 is formed by etching from the opening in the resist layer.

[0107] The above processing may be performed in the same process from the first surface 11 side and the second surface 12 side of the substrate, or one side may be processed first and then the other side. For example, first, a resist layer having an opening at a position corresponding to the through hole 13 is provided on the first surface 11 of the substrate, and etching is performed from the opening in the resist layer to form the portion of the through hole 13 extending from the first surface 11 of the substrate 10 to the narrowed portion 14; next, a resist layer having an opening at a position corresponding to the through hole 13 is provided on the second surface 12 of the substrate, and etching is performed from the opening in the resist layer to form the portion of the through hole 13 extending from the second surface 12 of the substrate 10 to the narrowed portion 14.

[0108] As the etching method, dry etching methods such as reactive ion etching and deep reactive ion etching, wet etching, etc. can be used.

[0109] The above-described laser irradiation and wet etching can also be combined as appropriate. For example, first, an altered layer is formed in the region of the substrate where the through-hole 13 is to be formed by laser irradiation, and then the substrate is immersed in hydrogen fluoride or the like to etch the altered layer. The through-hole 13 may be formed by such a method.

[0110] Alternatively, the through holes 13 may be formed by blasting the substrate with an abrasive material.

[0111] (Formation of through electrodes) Next, the through electrode 20 is formed. To form the through electrode 20, first, an adhesion layer 21 is formed on the first surface 11, the second surface 12, and the side surfaces of the through hole 13 of the substrate 10 by sputtering ion deposition, PVD, a sol-gel method, or a combination thereof, and then a seed layer 22 is formed on the adhesion layer 21 by sputtering, vapor deposition, or a combination thereof (see FIG. 9). For ease of understanding, in Figures 9 to 13, the adhesion layer 21 and seed layer 22 are shown as an underlayer 24 (a black thick film). However, since the adhesion layer 21 and seed layer 22 are usually thinner than the conductive layer 23, the underlayer 24 is not shown in Figure 1 mentioned above.

[0112] Next, as shown in FIG. 10, a resist layer 41 is partially formed on the base layer 24 formed on the first surface 11 of the substrate 10, and a resist layer 42 is partially formed on the base layer 24 formed on the second surface 12.

[0113] Subsequently, as shown in FIG. 11, the conductive layer 23 is formed by electrolytic plating on the underlayer 24 that is not covered with the resist layers 41 and 42.

[0114] Next, as shown in FIG. 12, the resist layers 41 and 42 are removed, and further, as shown in FIG. 13, the portions of the underlayer 24 that were covered with the resist layers 41 and 42 are removed by, for example, wet etching.

[0115] In this way, the through hole electrode substrate 1 shown in Fig. 1 can be obtained. Note that in the through hole electrode substrate 1 shown in Fig. 1, the illustration of the base layer 24 is omitted to avoid complication. [Example]

[0116] Hereinafter, embodiments of the present disclosure will be described in detail with reference to examples and comparative examples, but the embodiments of the present disclosure are not limited to the examples.

[0117] Examples 1 to 13 A 200 mm diameter alkali-free glass substrate (EN-Al manufactured by Asahi Glass Co., Ltd.) was subjected to laser processing and wet etching using hydrogen fluoride to produce a substrate having through-holes with the various values ​​shown in Table 1, as shown in Figure 2. Here, the hole diameter D1 and hole diameter D2 shown in Figure 2 were both 60 μm. The thermal expansion coefficient of the substrate was 3 ppm / K, and the dielectric loss tangent at a frequency of 20 GHz was 0.005. In addition, an adhesion layer having a thickness of 50 nm and made of zinc oxide (ZnO) was formed by a sol-gel method at predetermined locations, such as the side surfaces of the through holes, and then a seed layer having a thickness of 500 nm and made of copper (Cu) was formed by a sputtering method. Thereafter, a conductive layer made of copper (Cu) was formed by electrolytic plating to produce a through electrode substrate having the configuration shown in Fig. 1 and having through electrodes with the various values ​​shown in Table 1. In this way, through electrode substrates of Examples 1 to 13 having the various values ​​shown in Table 1 were prepared.

[0118] (Measurement and calculation of each value) An ion milling machine (Hitachi High-Tech, IM-4000) was used to obtain a cross section of each through-hole substrate, as shown in Figure 1. The diameter of the through-hole was measured using a length-measuring optical microscope (Olympus, STM-6-LM) and compared to the diameter of the through-hole in a plan view before the cross section was obtained, confirming that the cross section passed within ±5% of the center of the through-hole opening. The thickness t shown in Fig. 1, the hole diameter p, the distance d, and the thickness g shown in Fig. 2 were obtained by measuring the cross section with a length measuring optical microscope (Olympus Corporation, STM-6-LM). The units of the thickness t, distance d, and thickness g shown in Table 1 are all μm.

[0119] Here, the hole diameter p (μm) shown in Table 1 is the value measured by the distance between the two closest points on the left and right side surfaces of the through-hole in the cross section. The distance d shown in Table 1 is the average value of the values ​​on the left and right side surfaces of the obtained through-hole cross section.

[0120] In addition, the angle θ (°) shown in Table 1 was determined by drawing a line from the cross-sectional photograph connecting the edge of the narrowed portion on the right side of the cross-section of the through hole (the part where the left and right sides of the through hole are closest in the cross-section) to the edge of the opening of the through hole on the second surface side of the substrate (the line connecting Rp and R2 shown in Figure 2), and defining the angle between this line and the normal to the second surface of the substrate (N2 shown in Figure 2).

[0121] In addition, the value V shown in Table 1 (a value representing the ratio of the volume of the conductive layer inside the through hole to the volume of the through hole, expressed as a percentage; unit: %) was calculated by determining the volume of the through hole and the volume of the conductive layer inside the through hole from the cross-sectional photograph, and setting the obtained volume of the through hole to 100 to calculate the volume of the conductive layer inside the obtained through hole as a percentage.

[0122] (evaluation) In the heat cycle test, each of the through hole electrode substrates of Examples 1 to 13 was heated in a vacuum from -55°C to 125°C over 1 hour, held at 125°C for 1 hour, and then cooled from 125°C to -55°C over 1 hour. This was repeated 1000 times, and then the front and back of each through hole electrode substrate were observed using an optical microscope (Olympus STM-6-LM) to evaluate the occurrence of cracks and gaps. The results are shown in Table 1. As shown in Table 1, no cracks or gaps were found in any of Examples 1 to 13, and all of the results were good.

[0123] [Table 1]

[0124] (Comparative Examples 1 to 4) In the same manner as in Examples 1 to 13, attempts were made to fabricate through hole electrode substrates of Comparative Examples 1 to 4 having the various values ​​shown in Table 2. Note that the units of p, V, t, d, g, and θ in Table 2 are the same as those in Table 1 above. Here, in Comparative Example 1, the value of pore diameter p is smaller than the values ​​in Examples 1 to 13, and in Comparative Example 2, the value of pore diameter p is larger than the values ​​in Examples 1 to 13. In addition, in Comparative Example 3, the value of numerical value V is smaller than the values ​​in Examples 1 to 13, and in Comparative Example 4, the value of numerical value V is larger than the values ​​in Examples 1 to 13.

[0125] However, in Comparative Examples 1 and 2, it was difficult to stably form through holes and through electrodes of the desired shapes, and in Comparative Example 3, the electrical resistance of the through electrodes 20 became too high, resulting in high transmission loss. Furthermore, in Comparative Example 4, when a heat cycle test similar to that of Examples 1 to 13 was carried out, cracks or gaps were found. Therefore, as shown in Table 2, all of Comparative Examples 1 to 4 were found to have poor results.

[0126] [Table 2]

[0127] (Examples 14 to 31) Various filling resins and insulating resin layers shown in Table 3 were formed on the through hole electrode substrates of Examples 1 to 13 above, to prepare through hole electrode substrates of Examples 14 to 31 having the configuration shown in Fig. 5. The thickness of filling resin 31 on second surface 12 of substrate 10 in the configuration shown in Fig. 5 (more specifically, the thickness from second surface 12 of substrate 10 to the outermost surface of filling resin 31 in Fig. 5) was set to 25 µm. The thickness of insulating resin layer 50 on first surface 11 of substrate 10 in the configuration shown in Fig. 5 (more specifically, the thickness from first surface 11 of substrate 10 to the outermost surface of insulating resin layer 50 in Fig. 5) was also set to 25 µm.

[0128] (evaluation) In the heat cycle test, the through hole electrode substrates of Examples 14 to 31 were heated in a vacuum from -55°C to 125°C over 1 hour, held at 125°C for 1 hour, and then cooled from 125°C to -55°C over 1 hour. This was repeated 1000 times, and then the front and back of each through hole electrode substrate were observed using an optical microscope (Olympus STM-6-LM) to evaluate the occurrence of cracks and gaps. The results are shown in Table 3.

[0129] In Table 3, "tan δ" refers to the dielectric loss tangent of the filling resin and the insulating resin layer at a frequency of 20 GHz. In addition, "thermogravimetric change" refers to the thermogravimetric change (unit: weight %) of the filled resin filler contained in the filled resin at 250°C in the case of a filled resin, and to the thermogravimetric change (unit: weight %) of the insulating resin filler contained in the insulating resin layer at 250°C in the case of an insulating resin layer. In addition, "CTE" refers to the thermal expansion coefficient (unit: ppm / K) of the filled resin filler contained in the filled resin, in the case of a filled resin, and to the thermal expansion coefficient (unit: ppm / K) of the insulating resin filler contained in the insulating resin layer, in the case of an insulating resin layer. In addition, "volume fraction" refers to the volume fraction (unit: %) of the filled resin filler contained in the filled resin at 25°C for the filled resin, and refers to the volume fraction (unit: %) of the insulating resin filler contained in the insulating resin layer at 25°C for the insulating resin layer.

[0130] [Table 3]

[0131] As shown in Table 3, no cracks or gaps were found in any of Examples 14 to 31, and the results were good. [Explanation of symbols]

[0132] 1, 2, 3, 4, 5, 6 Through-hole electrode substrate 10 Substrate 11 Page 1 12 Side 2 13 Through hole 14 Stenosis 15 First side part 16 Second side part 20 Through electrode 21 Adhesion layer 22 Seed Layer 23 Conductive layer 24 Base layer 31 Filled Resin 41, 42 Resist layer 50 insulating resin layer 51 First insulating resin layer 52 Second insulating resin layer 61, 62, 63 Conductive vias 70 Side conductive layer 71 First side conductive layer 72 Second side conductive layer 80 Filling material 81 First Filler 82 Second Filler

Claims

1. a substrate including a first surface and a second surface located opposite to the first surface and having a through hole; a through electrode located in the through hole of the substrate, the through hole has a narrowed portion between the first surface and the second surface, where the hole diameter is smallest, the hole diameter p at the narrowed portion is 10 μm or more and 50 μm or less, the hole diameter D1 at the first surface is 60 μm or less, and the hole diameter D2 at the second surface is 60 μm or less, the through electrode is provided on a side surface of the through hole, the through electrode has an adhesive layer and a conductive layer in this order from a side surface of the through hole toward a center of the through hole, a thickness t of the conductive layer is in the range of 0.5 μm or more and 10 μm or less and is smaller than ½ of the hole diameter p; a volume of the conductive layer inside the through hole is 5% to 50% of a volume of the through hole, The thermal expansion coefficient of the substrate is 2 ppm / K or more and 8 ppm / K or less, The dielectric loss tangent of the substrate at a frequency of 20 GHz is 0.0003 or more and 0.005 or less, a filling resin positioned on the through electrode from a side surface of the through hole toward a center of the through hole and filling the through hole; the filled resin contains a filled resin filler; The filling resin filler is A through-hole electrode substrate having a thermogravimetric change of 3% by weight or less at 250°C.

2. The filling resin filler is A thermal expansion coefficient of 0.5 ppm / K or more and 8 ppm / K or less, The through hole electrode substrate according to claim 1 , wherein the filled resin contains the filled resin filler in an amount of 30% by volume or more and 80% by volume or less.

3. A through-electrode substrate as described in claim 1 or claim 2, wherein the dielectric tangent of the filled resin at a frequency of 20 GHz is 0.003 or more and 0.02 or less.

4. an insulating resin layer on the first surface side of the substrate; The through hole electrode substrate according to claim 1 , wherein the insulating resin constituting the insulating resin layer has a dielectric loss tangent of 0.001 or more and 0.01 or less at a frequency of 20 GHz.

5. the insulating resin contains an insulating resin filler, The insulating resin filler is The thermogravimetric change is within 3% by weight at 250°C, A thermal expansion coefficient of 0.5 ppm / K or more and 8 ppm / K or less, The through hole electrode substrate according to claim 4 , wherein the insulating resin filler is contained in an amount of more than 0% by volume and not more than 30% by volume of the insulating resin.

6. a substrate including a first surface and a second surface located opposite to the first surface and having a through hole; a through electrode located in the through hole of the substrate, the through hole has a narrowed portion between the first surface and the second surface, where the hole diameter is smallest, the hole diameter p at the narrowed portion is 10 μm or more and 50 μm or less, the hole diameter D1 at the first surface is 60 μm or less, and the hole diameter D2 at the second surface is 60 μm or less, the through electrode is provided on a side surface of the through hole, the through electrode has an adhesive layer and a conductive layer in this order from a side surface of the through hole toward a center of the through hole, a thickness t of the conductive layer is in the range of 0.5 μm or more and 10 μm or less and is smaller than ½ of the hole diameter p; a volume of the conductive layer inside the through hole is 5% to 50% of a volume of the through hole, The thermal expansion coefficient of the substrate is 2 ppm / K or more and 8 ppm / K or less, The dielectric loss tangent of the substrate at a frequency of 20 GHz is 0.0003 or more and 0.005 or less, an insulating resin layer on the first surface side of the substrate; the insulating resin constituting the insulating resin layer contains an insulating resin filler; The insulating resin filler is A through-hole electrode substrate having a thermogravimetric change of 3% by weight or less at 250°C.

7. The insulating resin filler is A thermal expansion coefficient of 0.5 ppm / K or more and 8 ppm / K or less, The through hole electrode substrate according to claim 6 , wherein the insulating resin filler is contained in an amount of more than 0% by volume and not more than 30% by volume of the insulating resin.

8. A through-electrode substrate as described in claim 6 or claim 7, wherein the dielectric tangent of the insulating resin at a frequency of 20 GHz is 0.001 or more and 0.01 or less.

9. 9. The through electrode substrate according to claim 6, wherein the through electrode substrate has a via hole penetrating the insulating resin layer at a position that does not overlap with the through hole when viewed from the normal direction of the first surface of the substrate, and has a conductive via filled with a conductive material inside the via hole.

10. 9. The through electrode substrate according to claim 6, wherein a via hole penetrating the insulating resin layer is located at a position overlapping the through hole when viewed from the normal direction of the first surface of the substrate, and a conductive via filled with a conductive material is located inside the via hole.

11. the insulating resin layer includes a first insulating resin layer in contact with the substrate and a second insulating resin layer laminated on the first insulating resin layer, a first via hole penetrating the first insulating resin layer at a position overlapping the through hole when viewed from a normal direction of the first surface of the substrate, and a conductive via filled with a conductive material inside the first via hole; 9. The through electrode substrate according to claim 6, wherein the through electrode substrate has a second via hole penetrating the second insulating resin layer at a position overlapping the conductive via when viewed from the normal direction of the first surface of the substrate, and has a side conductive layer made of a conductive material on the inner side surface of the second via hole.

12. the insulating resin layer includes a first insulating resin layer in contact with the substrate and a second insulating resin layer laminated on the first insulating resin layer, a first via hole penetrating the first insulating resin layer at a position overlapping the through hole when viewed from a normal direction of the first surface of the substrate, and a first side surface conductive layer made of a conductive material on an inner side surface of the first via hole; 9. The through electrode substrate according to claim 6, wherein a second via hole penetrating the second insulating resin layer is located at a position overlapping the first via hole when viewed from the normal direction of the first surface of the substrate, and a second side conductive layer made of a conductive material is located on the inner side of the second via hole.

13. a filling resin positioned on the through electrode from a side surface of the through hole toward a center of the through hole and filling the through hole; The through hole electrode substrate according to claim 6 , wherein the filled resin has a dielectric loss tangent of 0.003 or more and 0.02 or less at a frequency of 20 GHz.

14. the filled resin contains a filled resin filler; The filling resin filler is The thermogravimetric change is within 3% by weight at 250°C, A thermal expansion coefficient of 0.5 ppm / K or more and 8 ppm / K or less, The through hole electrode substrate according to claim 13 , wherein the filled resin filler is contained in an amount of 30% by volume or more and 80% by volume or less of the filled resin.

15. The through hole electrode substrate according to claim 1 , wherein the adhesion layer contains any one of titanium (Ti), titanium nitride (TiN), and zinc oxide (ZnO).

16. The through hole electrode substrate according to claim 1 , wherein the conductive layer contains copper (Cu).

17. the narrowed portion of the through hole is located at a position a distance d from either the first surface or the second surface of the substrate toward the other surface, The through hole electrode substrate according to claim 1 , wherein the distance d is equal to or greater than 20 μm and equal to or less than half the thickness g of the substrate.

18. The through hole electrode substrate according to claim 1 , wherein the thickness g of the substrate is 200 μm or more and 500 μm or less.

19. 19. The through-hole electrode substrate according to claim 1, wherein, on one of a pair of side surfaces constituting the through hole in a cross-sectional view, an angle θ1 formed by a line connecting the edge of the narrowing portion to the edge of the opening of the through hole on the first surface side of the substrate and a normal to the first surface of the substrate is 1.25° or more and 6.25° or less, and an angle θ2 formed by a line connecting the edge of the narrowing portion to the edge of the opening of the through hole on the second surface side of the substrate and a normal to the second surface of the substrate is 1.25° or more and 6.25° or less.

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