Through-hole electrode substrate

Abstract

To provide a through-hole electrode substrate that can suppress the occurrence of cracks in a filling material filled in a through-hole, and the occurrence of gaps between the filling material and the through-hole electrode formed along the side of the through-hole, due to thermal stress.SOLUTION: A through-hole electrode substrate according to the present disclosure includes a substrate having a through hole, a through electrode located on a side surface of the through hole, and a filling material located on the through electrode and filling the through hole, wherein the filling material includes a resin and a filler dispersed within the resin, the product of the elastic modulus and thermal expansion coefficient of the filling material is 20 Pa / K or more and 50 Pa / K or less, and the filler has a thermal expansion coefficient of -3×10-6 / K or more and 9×10-6 / K or less.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a through electrode substrate comprising 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 in 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 been used for various 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 the entire through hole is filled, and an unfilled type (also called a conformal via) that is provided on the side of the through hole and is hollow. 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]

[0003] [Patent Document 1] JP 2018-163986 A Summary of the Invention [Problem to be solved by the invention]

[0004] The through hole electrode substrate is subjected to a heat cycle test as a test for reliability of bonding with elements. For example, this heat cycle test involves heating the through hole electrode substrate from -55°C to 125°C over one hour, keeping it at 125°C for one hour, and then cooling it from 125°C to -55°C over one hour. In some tests, this heat cycle is performed 1,000 times on the through hole electrode substrate. Due to the thermal stress of this heat cycle test, for example, in the case where the through electrode is the above-mentioned filled via, there is a problem that cracks will occur in the conductive material such as copper (Cu) filled inside the through hole, or that gaps will occur between the through electrode and the side of the through hole. Furthermore, when the through electrode is the above-mentioned conformal via, there is a problem that cracks may occur in the filling material (e.g., resin) filled in the through hole, and that gaps may occur between the filling material and the through electrode formed along the side of the through hole.

[0005] 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]

[0006] One embodiment of the present disclosure includes a substrate including a first surface and a second surface located opposite to the first surface and having a through hole provided therein, a through electrode located on a side surface of the through hole, and a filler located on the through electrode and filling the through hole, the filler having a resin and a filler dispersed in the resin, the product of the elastic modulus and thermal expansion coefficient of the filler being 20 Pa / K or more and 50 Pa / K or less, and the filler having a thermal expansion coefficient of -3×10 -6 / K or more 9×10 -6 / K or less.

[0007] In the through electrode substrate according to an embodiment of the present disclosure, the resin may include a block polyimide copolymer having a fluorine group and a silicone group.

[0008] Furthermore, in a through electrode substrate according to one embodiment of the present disclosure, the resin includes a polymer A represented by the following general formula (1), a polymer B represented by the following general formula (2), and a polymer C represented by the following general formula (3), and the combined content of the polymer A, the polymer B, and the polymer C may be in the range of 100 mass% or less, the content of the polymer A may be greater than 15 mass% and not more than 40 mass%, the content of the polymer B may be 15 mass% or more and 30 mass% or less, and the content of the polymer C may be 30 mass% or more and 70 mass% or less.

[0009] [ka]

[0010] [ka]

[0011] [ka]

[0012] Furthermore, in a through electrode substrate according to one embodiment of the present disclosure, the filler has a first connection portion on the side of the first surface of the substrate, and the filler has a second connection portion on the side of the second surface of the substrate, the first connection portion and the second connection portion being electrically connected to the through electrode, and an opening through which the filler is partially exposed may be formed in both the first connection portion and the second connection portion, or in either the first connection portion or the second connection portion.

[0013] Furthermore, in a through electrode substrate according to one embodiment of the present disclosure, the through hole may have a narrowed portion therein having a smaller hole diameter than the hole diameter of the opening on the first surface side of the substrate and the hole diameter of the opening on the second surface side of the substrate. Effect of the Invention

[0014] According to an embodiment of the present disclosure, it is possible to prevent thermal stress from causing cracks in the filling material filled in the through hole and from causing gaps between the filling material and the through electrode formed along the side of the through hole. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a cross-sectional view showing a main part of a through electrode substrate according to an embodiment; [Diagram 2] A diagram showing the manufacturing process of a through electrode substrate [Diagram 3] A diagram showing the manufacturing process of the through electrode substrate following FIG. [Figure 4] A diagram showing the manufacturing process of the through electrode substrate following FIG. [Diagram 5] A diagram showing the manufacturing process of the through electrode substrate following FIG. [Figure 6] A diagram showing the manufacturing process of the through electrode substrate following FIG. 5. [Figure 7] FIG. 7 shows the manufacturing process of the through hole electrode substrate following FIG. [Figure 8] FIG. 8 shows the manufacturing process of the through hole electrode substrate following FIG. 7. [Figure 9] FIG. 11 is a cross-sectional view showing a through electrode substrate according to another embodiment; [Figure 10] FIG. 11 is a cross-sectional view showing a through electrode substrate according to another embodiment; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, the through-hole electrode substrate and the manufacturing method thereof according to the embodiment of the present disclosure will be described in detail with reference to the drawings. Note that the embodiment shown below is an example of the embodiment of the present disclosure, and the present disclosure is not limited to these embodiments. In addition, in this specification, terms such as "substrate", "substrate", "sheet" and "film" are not distinguished from each other based only on the difference in name. For example, "substrate" and "substrate" are concepts that include members that can be called sheets and films. Furthermore, terms such as "parallel" and "orthogonal" and values ​​of length and angle, which specify the shape and geometric conditions and their degree, used in this specification, are interpreted to include the range in which similar functions can be expected without being bound by strict meaning. In addition, in the drawings referred to in this embodiment, the same parts or parts having similar functions are given the same or similar symbols, and repeated explanations thereof may be omitted. In addition, the dimensional ratios of the drawings may differ from the actual ratios for convenience of explanation, and some of the configurations may be omitted from the drawings.

[0017] <Through electrode substrate> Hereinafter, an embodiment of the present disclosure will be described. First, the configuration of a through electrode substrate 1 according to an embodiment of the present disclosure will be described with reference to Fig. 1. Here, Fig. 1 is a cross-sectional view showing a main part of the through electrode substrate 1.

[0018] As shown in Figure 1, the through electrode substrate 1 comprises a substrate 10 including a first surface 11 and a second surface 12 located opposite the first surface 11 and having a through hole (through hole 13 in Figure 2 described later), a through electrode 20 located on the side of the through hole in the substrate 10, and a filler 30 located on the through electrode 20 and filling the through hole. That is, the through electrodes 20 of the through electrode substrate 1 correspond to one form of the above-mentioned conformal vias.

[0019] In the through electrode substrate 1, the through hole provided in the substrate 10 is filled with the through electrode 20 and the filler 30. For this reason, the through hole (through hole 13 in FIG. 2) provided in the substrate 10 is not indicated in FIG. 1. The shape of the through hole 13 is shown in FIG. 2, which will be described later. In addition, in FIG. 1, an enlarged cross-sectional view of one through electrode (through electrode 20) of the through electrode substrate 1 is shown as an example, but typically, the through electrode substrate 1 is provided with a plurality of through electrodes. Hereinafter, each component of the through electrode substrate 1 will be described.

[0020] (substrate) 1, the substrate 10 includes a first surface 11 and a second surface 12 located on the opposite side to the first surface 11. The substrate 10 also has a through hole 13 (see FIG. 2) extending from the first surface 11 to the second surface 12.

[0021] The substrate 10 includes an inorganic material having a certain insulating property. In the embodiment of the present disclosure, the substrate 10 may be any substrate that can be used as a substrate for a through-hole electrode substrate. For example, the substrate 10 is a glass substrate or a quartz substrate. An example of the glass used in the substrate 10 is non-alkali glass.

[0022] The alkali-free glass is glass that does not contain an alkali component such as sodium or potassium. The alkali-free glass contains, for example, boric acid instead of an alkali component. The alkali-free glass also contains an alkaline earth metal oxide such as calcium oxide or barium oxide. Examples of the alkali-free glass include EN-A1 manufactured by Asahi Glass Co., Ltd. and Eagle XG manufactured by Corning Co., Ltd.

[0023] The thickness (G) of substrate 10 is not particularly limited as long as it can be used as a substrate for a through electrode substrate. For example, the manufacturing process for a through electrode substrate may include a polishing process, typically a CMP (Chemical Mechanical Polishing) process, and if substrate 10 is too thin, it may lack strength and be damaged during this polishing process.

[0024] In addition, the manufacturing process for the through electrode substrate includes a step of forming a seed layer to form a thick through electrode by electrolytic plating. However, if the thickness of the substrate 10 is too large, the depth of the through hole will be large relative to the opening, and if the seed layer is formed by a sputtering method, 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 the subsequent electrolytic plating may not be as desired.

[0025] Taking the above into consideration, the thickness (G) of the substrate 10 can be set to, for example, not less than 300 μm and not more than 500 μm.

[0026] (Through hole) The substrate 10 is provided with a through hole 13 (see FIG. 2) extending from the first surface 11 to the second surface 12. 1, the through hole 13 has a larger hole diameter (HF) of the opening on the first surface 11 side than a hole diameter (HB) of the opening on the second surface 12 side. In other words, in a cross-sectional view, the side surface of the through hole 13 formed in the substrate 10 has a tapered shape that tapers from the first surface 11 side toward the second surface 12 side of the substrate 10. The reason why through hole 13 has a tapered shape is that it is difficult to process the side surfaces to be vertical, and if the side surfaces are vertical, it becomes difficult to form a seed layer for forming through electrode 20 inside through hole 13.

[0027] Here, the tapered shape mentioned above means that the shape is "tapered" from a broad perspective, and does not necessarily mean that the side surfaces of each portion of the through hole 13 extend linearly in a cross-sectional view. Even if the side surfaces extend in a curved shape, include a curved portion in part, or have both a straight portion and a curved portion, these shapes are included in the concept of a tapered shape as long as they are "tapered" from a broad perspective.

[0028] If the diameter of the opening of the through hole 13 is too large, it is not suitable for high density mounting. On the other hand, if the diameter is too small, it is difficult to form the desired through electrode. Taking these into consideration, the diameter of the opening of the through hole 13 can be set to, for example, 30 μm or more and 150 μm or less.

[0029] In the embodiment of the present disclosure, the cross-sectional shape of the through hole is not particularly limited as long as it can be used as a through hole of a through electrode substrate. For example, the through hole may have a narrowed portion therein whose hole diameter is smaller than the hole diameter of the opening on the first surface 11 side or the hole diameter of the opening on the second surface 12 side (see FIG. 10 described later).

[0030] (Through electrode) 1, the through electrode 20 is located on the side surface of the through hole 13 (see FIG. 2) in the through electrode substrate 1. As described above, the through electrode 20 of the through electrode substrate 1 corresponds to one form of a conformal via.

[0031] Here, the through electrode 20 is usually composed of multiple layers. For example, in the example shown in FIG. 1, the through electrode 20 has a seed layer 21 on the side of the through hole 13, and a plating layer 22 on the seed layer 21.

[0032] The seed layer 21 is a conductive layer that serves as a base for growing the plating layer 22 by precipitating metal ions in a plating solution during an electrolytic plating process in which the plating layer 22 is formed by electrolytic plating. The seed layer 21 may be made of a conductive material such as copper (Cu), titanium (Ti), or a combination of these. The material of the seed layer 21 may be the same as or different from the material of the plating layer 22. The thickness of the seed layer 21 is, for example, 50 nm or more and 1000 nm or less. To form the seed layer 21, for example, a sputtering method, a vapor deposition method, or a combination of a sputtering method and a vapor deposition method may be used.

[0033] The plating layer 22 is a conductive layer formed by electrolytic plating on the seed layer 21. Examples of materials that can be used to form the plating layer 22 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.

[0034] The thickness (T) of the through electrode 20 depends on the thickness (G) of the substrate 10 and the hole diameter (HF, HB) of the through hole opening, but can be any thickness that can be used as a through electrode for a conformal via. Here, the through electrode 20 is electrically connected to the terminal of the element, but if the thickness (T) is too small, there is a problem that the electrical resistance becomes large, whereas if the thickness (T) is too large, there is a problem that the filler is easily cracked due to thermal stress, or a gap is easily generated between the filler and the through electrode.

[0035] Taking these into consideration, the thickness (T) of the through electrode 20 can be set to, for example, not less than 5 μm and not more than 15 μm.

[0036] (filling) In the through electrode substrate 1 shown in Figure 1, the filler 30 is located on top of the through electrode 20 (i.e., closer to the center of the through hole 13 than the through electrode 20 located on the side of the through hole 13) and is formed so as to fill the through hole 13. The through electrode substrate according to the embodiment of the present disclosure is characterized by this filler 30, and by having the filler 30, it is possible to suppress the occurrence of cracks in the filler 30 due to thermal stress and the occurrence of gaps between the filler 30 and the through electrode 20.

[0037] Filler 30 has a resin composed of a specific composition described below and a specific filler dispersed within this resin, and the product of the elastic modulus and thermal expansion coefficient of filler 30 is 20 Pa / K or more and 50 Pa / K or less. The above-mentioned product of the elastic modulus and the thermal expansion coefficient was obtained by measuring the elastic modulus and the thermal expansion coefficient of the filler in a state where the filler is filled in the through hole electrode substrate. The filler and resin constituting the filling material 30 will be described below.

[0038] (Filler) The filler contained in the filling material 30 has a thermal expansion coefficient of −3×10 -6 / K or more 9×10 -6 / K or less, and is dispersed in a resin, which will be described later. As a filler having the above-mentioned thermal expansion coefficient, fused silica can be preferably mentioned. For example, Denka fused silica has a thermal expansion coefficient of 0.5×10 at 0℃ to 1000℃. -6 There is something called / K. The content of the filler in the filler 30 is preferably 70% by volume or more and 80% by volume or less of the filler 30. If the content of the filler is within this range, as in the examples described later, it is possible to suppress the occurrence of cracks in the filler filled in the through-hole of the through-hole electrode substrate due to thermal stress, and the occurrence of gaps between the filler and the through-hole electrode formed along the side surface of the through-hole.

[0039] (resin) The resin constituting the filler 30 contains a block polyimide copolymer having a fluorine group and a silicone group. Preferably, the resin constituting the filler 30 includes a polymer A represented by the following general formula (1), a polymer B represented by the following general formula (2), and a polymer C represented by the following general formula (3), wherein the combined content of polymer A, polymer B, and polymer C is in the range of 100 mass% or less, the content of polymer A is greater than 15 mass% and 40 mass% or less, the content of polymer B is 15 mass% or more and 30 mass% or less, and the content of polymer C is 30 mass% or more and 70 mass% or less.

[0040] [ka]

[0041] [ka]

[0042] [ka]

[0043] The resin constituting the filler 30 may contain a photosensitive material and may also contain various other additives. For example, if the resin contains a photosensitive material, a resin film containing the photosensitive material can be attached to the first surface 11 and the second surface 12 of the substrate 10 by a technique such as vacuum lamination, and then exposure and development processes can be performed to form a filler 30 in the through hole 13.

[0044] <Method of manufacturing through electrode substrate> Next, an example of a method for manufacturing the through hole electrode substrate 1 shown in FIG. 1 will be described with reference to FIGS.

[0045] (Manufacture of substrates having through holes) First, a substrate is prepared that includes a first surface 11 and a second surface 12 located opposite the first surface 11. A laser is then irradiated from the side where the opening of the through hole has a larger hole diameter (the first surface 11 side in the case of the through electrode substrate 1 shown in FIG. 1), thereby producing a substrate 10 having a through hole 13 of the desired shape, as shown in FIG. 2.

[0046] As a laser for laser processing, an excimer laser, a Nd:YAG laser, a femtosecond laser, etc., can be used. When using a Nd:YAG laser, a fundamental wave with a wavelength of 1064 nm, a second harmonic with a wavelength of 532 nm, a third harmonic with a wavelength of 355 nm, etc. can be used.

[0047] As another manufacturing method, the through-holes 13 may be formed by providing a resist layer having openings at positions corresponding to the through-holes 13 and performing etching through the openings in the resist layer. As the etching method, a dry etching method such as a reactive ion etching method or a deep reactive ion etching method, or a wet etching method can be used.

[0048] The above-mentioned laser irradiation and wet etching can also be appropriately combined. 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.

[0049] Alternatively, the through holes 13 may be formed by blasting the substrate with an abrasive material.

[0050] (Formation of through electrodes) Next, the through electrodes 20 are formed. First, a seed layer 21A is formed on the first surface 11, the second surface 12, and the side surfaces of the through-holes 13 of the substrate as shown in FIG. 3 by sputtering, vapor deposition, or a combination of these. Next, as shown in FIG. 4, a resist layer 41 is partially formed on the seed layer 21A formed on the first surface 11, and a resist layer 42 is partially formed on the seed layer 21A formed on the second surface 12. Subsequently, as shown in FIG. 5, a plating layer 22 is formed by electrolytic plating on the seed layer 21A that is not covered by the resist layers 41 and . Next, as shown in FIG. 6, the resist layers 41 and 42 are removed, and further, as shown in FIG. 7, the portions of the seed layer 21A that were covered with the resist layers 41 and 42 are removed by, for example, wet etching. In this manner, the through electrode 20 can be formed.

[0051] (Formation of filling) Thereafter, as shown in FIG. 8, a filler 30 is formed on the through electrode 20 (on the center side of the through hole 13) of the through electrode substrate 1 manufactured as described above.

[0052] To form the filler 30, for example, first, a film composed of the above-mentioned resin containing the above-mentioned filler is attached to each opening of the through hole 13 on both the first surface 11 side and the second surface 12 side of the substrate 10 by a technique such as vacuum lamination, thereby filling the through hole. The excess film on the first surface 11 and the second surface 12 of the substrate can be removed by, for example, scraping it off with a squeegee. It can also be removed by carrying out a descum treatment using oxygen gas. In this manner, the through electrode substrate 1 shown in FIG. 1 can be obtained.

[0053] (Another embodiment 1) Next, another embodiment will be described. First, the through electrode substrate 2 will be described with reference to Fig. 9. Here, Fig. 9 is a cross-sectional view showing a main part of the through electrode substrate 2. Note that components similar to those of the above-mentioned through electrode substrate 1 are given the same reference numerals and will be described below.

[0054] As shown in Figure 9, in the through electrode substrate 2, similar to the through electrode substrate 1 shown in Figure 1, a through hole is provided in the substrate 10 from the first surface 11 to the second surface 12, a through electrode 20 is provided on the side surface of the through hole, and a filler 30 is formed on the through electrode 20 (towards the center of the through hole) so as to fill the through hole. Although not shown, in the through electrode substrate 2 as well, the through electrode 20 may have a seed layer on the side of the through hole, and a plating layer on the seed layer.

[0055] 1 has a portion that spreads outward from the center of the through hole 13 on the first surface 11 and the second surface 12 of the substrate 10. In the through electrode substrate 1, the through electrode 20 is connected to a terminal of an element or the like at this spreading portion.

[0056] 9, a first connection portion 51 is formed on the first surface 11 side of the filler 30 formed in the through hole, and a second connection portion 52 is formed on the second surface 12 side, and the first connection portion 51 and the second connection portion 52 are electrically connected to the through electrode 20. In the through electrode substrate 2, the first connection portion 51 and the second connection portion 52 connect the through electrode 20 to a terminal of an element or the like. That is, the form of the through electrode substrate 2 shown in FIG. 9 corresponds to a so-called metal cap structure. The advantage of this configuration is that the connection to the terminals of the elements, etc. can be made at the opening position (or within the opening) of the through hole in a plan view, which allows for higher density mounting, similar to the case of filled vias.

[0057] In this embodiment, it is preferable that an opening that partially exposes the filler 30 is formed in both the first connection part 51 and the second connection part 52, or in either the first connection part 51 or the second connection part 52. This is because the presence of such an opening allows gas generated from the filler 30 to be released. For example, in the through electrode substrate 2 shown in FIG.

[0058] (Another embodiment 2) Next, the through electrode substrate 3 will be described with reference to Fig. 10. Here, Fig. 10 is a cross-sectional view showing a main part of the through electrode substrate 3. Note that components similar to those of the through electrode substrate 1 described above are given the same reference numerals and will be described below.

[0059] As shown in Figure 10, in the through electrode substrate 3, similar to the through electrode substrate 1 shown in Figure 1, a through hole is provided in the substrate 10 from the first surface 11 to the second surface 12, a through electrode 20 is provided on the side surface of the through hole, and a filler 30 is formed on the through electrode 20 (towards the center of the through hole) so as to fill the through hole. Although not shown, in the through electrode substrate 3 as well, the through electrode 20 may have a seed layer on the side of the through hole, and a plating layer may be provided on the seed layer.

[0060] Here, the through hole 13 of the through electrode substrate 1 shown in FIG. 1 has a larger hole diameter (HF) of the opening on the first surface 11 side than a hole diameter (HB) of the opening on the second surface 12 side, and in cross-sectional view, the side of the through hole 13 formed in the substrate 10 has a tapered shape that tapers from the first surface 11 side toward the second surface 12 side of the substrate 10.

[0061] On the other hand, the through hole of the through electrode substrate 3 shown in FIG. 10 has therein a narrowed portion 70 whose hole diameter is smaller than the hole diameter of the opening on the first surface 11 side and the hole diameter of the opening on the second surface 12 side. More specifically, in the through hole of the through electrode substrate 3 shown in FIG. 10, the hole diameter of the opening on the first surface 11 side and the hole diameter of the opening on the second surface 12 side are the same size (HF3), and the hole diameter (P) of the narrowed portion 70 is smaller than the hole diameter (HF3) of each of the above-mentioned openings. An advantage of such a configuration is that it is possible to prevent the opening of the through hole in the through electrode substrate from becoming larger in size in accordance with the thickness of the substrate, thereby enabling higher density mounting.

[0062] 1, for example, the hole diameter (HB) of the opening on the second surface 12 side is the smallest of the hole diameters of the through-hole 13, and this smallest hole diameter cannot be made small when considering connection with elements, etc. Therefore, as long as the side surface of the through-hole is not vertical but has an inclination, when the thickness (G) of the substrate 10 increases, the hole diameter (HF) of the opening on the first surface 11 side becomes larger than the hole diameter (HB) of the opening on the second surface 12 side.

[0063] On the other hand, in the through electrode substrate 3 shown in FIG. 10, the minimum hole diameter of the through hole of the through electrode substrate 3 is the hole diameter (P) of the narrowed portion 70, and even if this hole diameter (P) is the same as the hole diameter (HB) of the opening on the second surface 12 side of the through hole 13 of the through electrode substrate 1 shown in FIG. 1, for example, when the angle of inclination of the side of the through hole is the same as the angle of inclination of the side of the through hole 13 of the through electrode substrate 1 shown in FIG. 1, the hole diameter (HF3) of the opening on the first surface 11 side and the hole diameter (HF3) of the opening on the second surface 12 side can be made smaller than the hole diameter (HF) of the opening on the first surface 11 side of the through electrode substrate 1 shown in FIG. 1 until the thickness of the substrate 10 becomes twice that of the through electrode substrate 1 shown in FIG. 1.

[0064] Note that the through electrode 20 of the through electrode substrate 3 shown in FIG. 10 has a portion that extends outward from the center of the through hole on the first surface 11 and the second surface 12 of the substrate 10, similar to the through electrode substrate 1 shown in FIG. 1, but this embodiment is not limited to this and may have, for example, a so-called metal cap structure, such as the through electrode substrate 2 shown in FIG. 9. That is, the through electrode substrate 3 shown in Figure 10 may have a first connection portion on the first surface 11 side of the filler 30 formed in the through hole, and a second connection portion on the second surface 12 side, and the first connection portion and the second connection portion may be electrically connected to the through electrode 20. In this case as well, the connection with the terminals of the elements etc. can be made at the opening position (or within the opening) of the through hole in a plan view, so that higher density mounting is possible, similar to the case of filled vias. EXAMPLES

[0065] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to examples and comparative examples. However, the embodiments of the present disclosure are not limited to the examples.

[0066] (Examples 1 to 7) As the through electrode substrates of Examples 1 to 7, through electrode substrates having through electrodes with the structure shown in FIG. 1 were manufactured.

[0067] First, a through hole was formed in a non-alkali glass substrate (EN-Al manufactured by Asahi Glass Co., Ltd.) with a diameter of 200 mm and a thickness of 400 μm by performing laser processing and wet etching processing using hydrogen fluoride. Here, the hole diameter (HF) of the opening on the first surface side (front surface side) of the through hole was 85 μm, and the hole diameter (HB) of the opening on the second surface side (back surface side) was 50 μm.

[0068] Next, a seed layer having a thickness of 1 μm of copper (Cu) on a thickness of 50 nm of titanium (Ti) was formed by sputtering, and a plating layer having a thickness of 6 μm of copper (Cu) was formed on top of that by electrolytic plating to form a through electrode.

[0069] Next, a film having the filler content and resin composition shown in Table 1 was attached to both the first and second surfaces of the substrate by vacuum lamination to form a filler for filling the through-holes. The excess film on the first and second surfaces of the substrate was first scraped off with a squeegee, and then removed by descum treatment using oxygen gas. The filler has a thermal expansion coefficient of 0.5×10 -6 The resin used was polymer A represented by general formula (1), polymer B represented by general formula (2), and polymer C represented by general formula (3) in the amounts shown in Table 1.

[0070] (Measurement of filler content) A cross section of the through hole of each through electrode substrate was obtained using a focused ion beam (FIB), and the cross section was further etched by 50 nm using oxygen plasma. The obtained sample was observed with an SEM, the image was captured, the filler portion was identified from the image, and the area ratio of the filler was obtained, which was taken as the content ratio.

[0071] (Measurement of Resin Composition Content) An IRT-1000 microscopic measurement unit was attached to the sample chamber of a JASCO FTIR4600, and IR (infrared spectroscopy) measurement was performed through an ATR (attenuated total reflection) measurement prism. The mass percentages of polymers A, B, and C were calculated from the peak intensities derived from the functional groups possessed by polymers A, B, and C.

[0072] (Measurement of elastic modulus) A cross section of the through hole of each through electrode substrate was obtained using an ion milling device (IM-4000, manufactured by Hitachi High-Technologies Corporation). The elastic modulus (E) of this cross section was measured using a KLA Corporation iNanoInForce50 type device with a Berkovich indenter at an approach speed of 100 nm / s and 50 mN / s in accordance with ISO14577.

[0073] (Measurement of thermal expansion coefficient) The first surface (front surface) and second surface (back surface) of each through electrode substrate were polished until the filler formed in the through hole was exposed, and then etched 5 μm with hydrofluoric acid to create a sample in which the filler protruded 5 μm convexly from the substrate surface. The temperature of this sample was changed from 0℃ to 300℃, and measurements were performed using a dual-path Michaelson type laser beam interference method using an Advance Riko Co., Ltd. laser thermal dilatometer (LIX-2) in accordance with JIS R3251-1995, and the thermal expansion coefficient (α) was calculated from the amount of deformation.

[0074] (Comparative Examples 1 to 6) In the same manner as in Examples 1 to 7, through electrode substrates of Comparative Examples 1 to 6 having the filler contents and resin compositions shown in Table 2 were produced. Here, the filler content in Comparative Example 1 is less than that in Examples 1 to 7, and the filler content in Comparative Example 2 is greater than that in Examples 1 to 7. Furthermore, Comparative Examples 3 to 6 differ from Examples 1 to 7 in terms of resin composition.

[0075] (Rating 1) To evaluate the filling property of the filler, the cross section of the through hole of each of the through hole electrode substrates of Examples 1 to 7 and Comparative Examples 1 to 6 was observed by SEM to evaluate whether the filler was well filled in the through hole. Those in which voids or the like were generated were regarded as failing. (Rating 2) As a heat cycle test for evaluating reliability, each through electrode substrate was subjected to heating from -55°C to 125°C and cooling from 125°C to -55°C 1000 times. Thereafter, the first and second surfaces of each through-hole electrode substrate were observed with an optical microscope to evaluate whether or not cracks had occurred in the through-hole filling material. Furthermore, the cross section of the through-hole was observed with an SEM to evaluate whether or not cracks had occurred in the through-hole filling material and whether or not gaps had occurred between the filling material and the through-hole electrode. Those with cracks or gaps were judged to have failed. (judgement) A sample that passed both the above evaluations 1 and 2 was judged as "passed." On the other hand, a sample that failed either the above evaluations 1 or 2 was judged as "failed." The results are shown in Tables 1 and 2.

[0076] [Table 1]

[0077] [Table 2]

[0078] As shown in Table 1, in all of Examples 1 to 7, the product (E×α) of the elastic modulus (E) and the thermal expansion coefficient (α) of the filler was 20 Pa / K or more and 50 Pa / K or less, and the above evaluations were all judged to be pass.

[0079] On the other hand, as shown in Table 2, all of Comparative Examples 1 to 6 were judged to be unacceptable. Note that Comparative Examples 2, 5, and 6 had already failed in Evaluation 1. [Explanation of symbols]

[0080] 1, 2, 3 Through-hole electrode substrate 10 Substrate 11 Page 1 12 Side 2 13 Through hole 20 Through electrode 21, 21A seed layer 22 Plating layer 30 fillings 41, 42 Resist layer 51 First connection part 52 Second connection part 60 Opening 70 Stenosis

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 on a side surface of the through hole; a filler located on the through electrode and filling the through hole; The filling material includes a resin and a filler dispersed in the resin, The filler has a product of elastic modulus and thermal expansion coefficient of 20 Pa / K or more and 50 Pa / K or less, The filler has a thermal expansion coefficient of −3×10 －６ / K or more 9×10 －６ / K or less.

2. The through hole electrode substrate according to claim 1 , wherein the resin contains a block polyimide copolymer having a fluorine group and a silicone group.

3. The resin is The polymer A includes a polymer A represented by the following general formula (1), a polymer B represented by the following general formula (2), and a polymer C represented by the following general formula (3), The total content of the polymer A, the polymer B, and the polymer C is in the range of 100 mass% or less, The content of the polymer A is more than 15% by mass and not more than 40% by mass, The content of the polymer B is 15% by mass or more and 30% by mass or less, The through hole electrode substrate according to claim 2 , wherein the content of the polymer C is 30% by mass or more and 70% by mass or less. 【Chemistry 1】 【Chemistry 2】 【Chemistry 3】

4. The filler has a first connection portion on a side of the first surface of the substrate, A second connection portion is provided on the filler on the second surface side of the substrate, the first connection portion and the second connection portion are electrically connected to the through electrode, The through electrode substrate according to claim 1 , wherein an opening is formed in both the first connection portion and the second connection portion, or in either the first connection portion or the second connection portion, to partially expose the filling material.

5. The through hole is 5. The through electrode substrate according to claim 1, further comprising a narrowed portion having a smaller hole diameter than the hole diameter of the opening on the first surface side of the substrate and the hole diameter of the opening on the second surface side of the substrate.

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