Through-hole electrode substrate

Abstract

To provide a through-hole electrode substrate.SOLUTION: A through-hole electrode substrate 10 of an embodiment of the present invention comprises: a substrate 11 having a first face 110 and a second face 120 and including a through hole 15 penetrating the first face 110 and the second face 120; a through-hole electrode 100 arranged inside of the through hole 15; and a wiring laminate 70 located on the first face 110. The through-hole electrode 100 includes: a first portion 105 closing the through hole 15 on the first face 110 side; and a second portion 103 arranged along an inner face of the through hole 15. The wiring laminate 70 includes: an interlayer insulation layer 710 having an opening 180 formed thereon; and a wiring layer 720 including a portion located on the opening 180 and connected to the first portion 105 of the through-hole electrode 100.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] In recent years, three-dimensional packaging technology has been used, in which semiconductor circuit substrates on which integrated circuits are formed are stacked. In this packaging technology, a substrate with through electrodes formed thereon is used. Such a substrate is also called an interposer. The through electrodes are formed by placing a conductor in a through hole formed in the substrate. As the integration of the circuits to be mounted increases, high integration is also required in through electrode substrates. For example, a technology has been developed that efficiently connects the wiring portion and the through electrode by placing the wiring portion so that it overlaps the portion where the through hole is provided.

[0003] Through electrodes include conformal electrodes (conformal vias) formed with a conductor that does not fill the inside of the through hole, and filled electrodes (filled vias) that fill the inside of the through hole. In the case of conformal electrodes, there is no electrode that fills the inside of the through electrode, which can reduce manufacturing costs and stress caused by the through electrode. On the other hand, since wiring cannot be arranged to overlap the part where the through hole is provided, design difficulties arise in achieving high integration. Patent Document 1 discloses a technology in which a conductor is arranged to block the surface side of the substrate of the through hole even in conformal through electrodes. This technology discloses a technology that facilitates high integration by efficiently arranging wiring on at least one side of the substrate. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2017 / 209296 [Patent Document 2] Japanese Patent Application Laid-Open No. 2008-227433 [Patent Document 3] International Publication No. 2011 / 127041 Summary of the Invention

[0005] According to one embodiment of the present disclosure, there is provided a through electrode substrate comprising: a substrate having a first surface and a second surface, the substrate including a through hole penetrating the first surface and the second surface; a through electrode disposed inside the through hole; and a wiring stack located on the first surface, the through electrode including a first portion that blocks the through hole on the first surface side and a second portion that is disposed along the inner side of the through hole; and the wiring stack including an interlayer insulating layer having an opening formed therein; and a wiring layer including a portion located at the opening and connected to the first portion of the through electrode.

[0006] The opening in the interlayer insulating layer may extend in a direction perpendicular to the first surface.

[0007] A contact region, which is a region where the portion of the wiring layer located in the opening of the interlayer insulating layer contacts the first portion of the through electrode, may be surrounded by the outer edge of the through hole on the first surface when viewed along a direction perpendicular to the first surface.

[0008] A contact region, which is a region where the portion of the wiring layer located in the opening of the interlayer insulating layer contacts the first portion of the through electrode, may overlap with the through hole when viewed along a direction perpendicular to the first surface, but may not be surrounded by the outer edge of the through hole on the first surface.

[0009] The wiring layer may include a wiring extending in an in-plane direction of the first surface, and a connection layer located in the opening of the interlayer insulating layer and connecting the wiring to the first portion of the through electrode.

[0010] A plurality of the openings may be formed in the interlayer insulating layer, and the wiring layer may include a plurality of the connection layers located in each of the openings and connecting the wiring to the first portion of the through electrode.

[0011] The interlayer insulating layer may include an organic material.

[0012] The interlayer insulating layer may contain an inorganic material.

[0013] The second portion may extend along the inner surface of the through hole to the second surface side of the through hole, and the second portion may be positioned so as not to block any area inside the through hole other than the first portion.

[0014] A space within the through hole surrounded by the through electrode may be filled with an insulator. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 2 is a diagram illustrating a cross-sectional structure of an electronic unit according to the first embodiment of the present disclosure. [Figure 2] 2A and 2B are diagrams illustrating a cross-sectional structure of a through electrode substrate according to a first embodiment of the present disclosure. [Figure 3] 3A and 3B are diagrams illustrating the structure (blocking portion) of the first surface side of the through electrode in the first embodiment of the present disclosure. [Figure 4] 3A to 3C are diagrams illustrating a method for manufacturing a through hole electrode substrate according to the first embodiment of the present disclosure. [Figure 5] 3A to 3C are diagrams illustrating a method for manufacturing a through hole electrode substrate according to the first embodiment of the present disclosure. [Figure 6] 3A to 3C are diagrams illustrating a method for manufacturing a through hole electrode substrate according to the first embodiment of the present disclosure. [Figure 7] 3A to 3C are diagrams illustrating a method for manufacturing a through hole electrode substrate according to the first embodiment of the present disclosure. [Figure 8] 3A to 3C are diagrams illustrating a method for manufacturing a through hole electrode substrate according to the first embodiment of the present disclosure. [Figure 9] 3A to 3C are diagrams illustrating a method for manufacturing a through hole electrode substrate according to the first embodiment of the present disclosure. [Figure 10] 3A to 3C are diagrams illustrating a method for manufacturing a through hole electrode substrate according to the first embodiment of the present disclosure. [Figure 11] 3A to 3C are diagrams illustrating a method for manufacturing a through hole electrode substrate according to the first embodiment of the present disclosure. [Figure 12] 1 is an electron microscope photograph of a cross section of a through electrode. [Figure 13] 10A to 10C are diagrams illustrating a method for manufacturing a through hole electrode substrate according to a second embodiment of the present disclosure. [Figure 14] 10A to 10C are diagrams illustrating a method for manufacturing a through hole electrode substrate according to a second embodiment of the present disclosure. [Figure 15] 10A to 10C are diagrams illustrating a method for manufacturing a through hole electrode substrate according to a second embodiment of the present disclosure. [Figure 16] 10A to 10C are diagrams illustrating a method for manufacturing a through hole electrode substrate according to a third embodiment of the present disclosure. [Figure 17] 10A to 10C are diagrams illustrating a method for manufacturing a through hole electrode substrate according to a third embodiment of the present disclosure. [Figure 18] 10A to 10C are diagrams illustrating a method for manufacturing a through hole electrode substrate according to a third embodiment of the present disclosure. [Figure 19] 10A and 10B are diagrams illustrating a cross-sectional structure of a through electrode according to a fourth embodiment of the present disclosure. [Figure 20] 10A and 10B are diagrams illustrating the structure (blocking portion) of the first surface side of the through electrode in the fourth embodiment of the present disclosure. [Figure 21] FIG. 10 is a diagram illustrating a cross-sectional structure of a through electrode according to a fifth embodiment of the present disclosure. [Figure 22] FIG. 13 is a diagram illustrating a cross-sectional structure of a through electrode according to a sixth embodiment of the present disclosure. [Figure 23] FIG. 13 is a diagram illustrating a cross-sectional structure of a wiring board according to a sixth embodiment of the present disclosure. [Figure 24] FIG. 13 is a diagram illustrating a cross-sectional structure of a through electrode according to a seventh embodiment of the present disclosure. [Figure 25] 13A to 13C are views illustrating a method for manufacturing a through hole electrode substrate according to an eighth embodiment of the present disclosure. [Figure 26] 13A to 13C are views illustrating a method for manufacturing a through hole electrode substrate according to an eighth embodiment of the present disclosure. [Figure 27]13A to 13C are views illustrating a method for manufacturing a through hole electrode substrate according to an eighth embodiment of the present disclosure. [Figure 28] 13A to 13C are views illustrating a method for manufacturing a through hole electrode substrate according to an eighth embodiment of the present disclosure. [Figure 29] FIG. 1 is a diagram illustrating an electronic device including an electronic unit according to a first embodiment of the present disclosure. [Figure 30A] FIG. 4 is a diagram illustrating an example of a first electrolytic plating step. [Figure 30B] FIG. 10 is a diagram illustrating an example of a second electrolytic plating step. [Figure 30C] FIG. 10 is a diagram illustrating an example of a second electrolytic plating step. [Figure 30D] FIG. 10 is a diagram illustrating an example of a second electrolytic plating step. [Figure 31] FIG. 3 is a diagram illustrating an example of a cross-sectional structure of a second metal layer. [Figure 32] 10A and 10B are diagrams illustrating an example of a cross-sectional structure of a blocking portion of a through electrode. [Figure 33] 10A to 10C are diagrams illustrating an example of a method for manufacturing an electronic unit. [Figure 34] 10A to 10C are diagrams illustrating an example of a method for manufacturing an electronic unit. [Figure 35] 10A to 10C are diagrams illustrating an example of a method for manufacturing an electronic unit. [Figure 36] 10A and 10B are diagrams illustrating an example of a structure for connecting a blocking portion of a through hole electrode substrate and an electrode of an electronic device. [Figure 37] 10A and 10B are diagrams illustrating an example of a structure for connecting a blocking portion of a through hole electrode substrate and an electrode of an electronic device. [Figure 38] 10A and 10B are diagrams illustrating an example of a structure for connecting a blocking portion of a through hole electrode substrate and an electrode of an electronic device. [Figure 39] 10A and 10B are diagrams illustrating an example of a structure for connecting a blocking portion of a through hole electrode substrate and an electrode of an electronic device. [Figure 40A] 10A and 10B are diagrams illustrating an example of a cross-sectional structure of a wiring layer connected to a blocking portion of a through electrode substrate. [Figure 40B] FIG. 40B is a plan view showing the wiring layer of FIG. 40A. [Figure 41A] 10A and 10B are diagrams illustrating an example of a cross-sectional structure of a wiring layer connected to a blocking portion of a through electrode substrate. [Figure 41B] FIG. 41B is a plan view showing the wiring layer of FIG. 41A. [Figure 42A] 10A and 10B are diagrams illustrating an example of a cross-sectional structure of a wiring layer connected to a blocking portion of a through electrode substrate. [Figure 42B] FIG. 42B is a plan view showing the wiring layer of FIG. 42A. [Figure 43A] 10A and 10B are diagrams illustrating an example of a cross-sectional structure of a wiring layer connected to a blocking portion of a through electrode substrate. [Figure 43B] FIG. 43B is a plan view showing the wiring layer of FIG. 43A. [Figure 44A] FIG. 1 is a plan view showing an example of a sample of a through electrode substrate. [Figure 44B] 44B is a cross-sectional view of the through hole electrode substrate of FIG. 44A taken along line E1-E1. [Figure 45A] FIG. 10 is a plan view showing another example of a sample of a through electrode substrate. [Figure 45B] 45B is a cross-sectional view of the through hole electrode substrate of FIG. 45A taken along line E2-E2. DETAILED DESCRIPTION OF THE INVENTION

[0016] An electronic unit including a through-hole electrode substrate according to an embodiment of the present disclosure will be described in detail below with reference to the drawings. Note that the following embodiments are merely examples of the present invention, and the present invention should not be construed as being limited to these embodiments. In the drawings referred to in this embodiment, identical or similar symbols (symbols consisting of a number followed by A, B, etc.) are used to designate identical or similar functions, and repeated explanations may be omitted. For convenience of explanation, the dimensional ratios in the drawings may differ from the actual ratios, and some components may be omitted from the drawings. Furthermore, terms specifying shapes, geometric conditions, and their degrees, such as "circular" and "vertical," as well as values of lengths and angles, are not limited to their strict meanings but should be interpreted to encompass a range within which similar functions can be expected.

[0017] First Embodiment [1. Structure of semiconductor substrate] FIG. 1 is a diagram illustrating a cross-sectional structure of an electronic unit according to a first embodiment of the present disclosure. The electronic unit 1000 includes a wiring substrate 80, a printed wiring board 91, and electronic devices 92 and 93. The wiring substrate 80 includes a through electrode substrate 10 and a wiring structure 50. The electronic devices 92 and 93 are connected to the printed wiring board 91 via the wiring substrate 80. The wiring substrate 80 is an example of an interposer. The wiring substrate 80 includes a through electrode substrate 10 and a wiring laminate 70. The through electrode substrate 10 has through electrodes 100 that penetrate the substrate. A detailed configuration will be described later. The wiring laminate 70 has stacked copper wiring formed therein. An electrode 811 arranged on a first surface 810 of the wiring substrate 80 and the through electrodes 100 exposed on a second surface 820 of the wiring substrate 80 are connected to each other by wiring arranged in the wiring laminate 70.

[0018] In this example, printed wiring board 91 is a substrate containing a resin such as glass epoxy. Printed wiring board 91 is a substrate on which copper wiring is formed using a copper-clad laminate. In this example, electrode 911 arranged on a first surface 910 of printed wiring board 91 and electrode 921 arranged on a second surface 920 of printed wiring board 91 are connected to each other by internal copper wiring. Electrode 911 and through electrode 100 are connected by bump 891, thereby electrically connecting printed wiring board 91 and wiring substrate 80.

[0019] The electronic devices 92 and 93 include elements formed of semiconductors such as silicon. For example, the electronic devices 92 and 93 are CPUs, memories, FPGAs, sensors, etc. The electronic devices may be configured as a stack of multiple semiconductor substrates. For example, a memory may have a structure that combines a memory controller and a stack of memories such as HBM (High Bandwidth Memory).

[0020] In this example, an electrode 922 of the electronic device 92 is connected to an electrode 811 of the wiring substrate 80 via a bump 892, thereby electrically connecting the electronic device 92 and the wiring substrate 80. An electrode 923 of the electronic device 93 is connected to an electrode 811 of the wiring substrate 80 via a bump 893, thereby electrically connecting the electronic device 93 and the wiring substrate 80. The electronic devices 92 and 93 are also electrically connected via the wiring substrate 80.

[0021] [2. Structure of the through-hole electrode substrate] Next, the through electrode substrate 10 and the through electrodes 100 disposed thereon will be described.

[0022] FIG. 2 is a diagram illustrating the cross-sectional structure of the through electrode substrate in the first embodiment of the present disclosure. FIG. 2 is an enlarged view of region A1 in FIG. 1. The through electrode substrate 10 includes a glass substrate 11 and through electrodes 100. The glass substrate 11 has a first surface 110 and a second surface 120. A wiring stack 70 connected to the through electrodes 100 is disposed on the first surface 110 side of the glass substrate 11. The wiring stack 70 includes an interlayer insulating layer 710 and a wiring layer 720. The interlayer insulating layer 710 may be formed of an organic material such as polyimide or acrylic, or may be formed of an inorganic material such as silicon oxide. The wiring layer 720 is formed by a semi-additive method, a dual damascene method, or the like.

[0023] The glass substrate 11 is provided with through holes 15 that penetrate the first surface 110 and the second surface 120. The diameter of the through holes 15 has a minimum value dcm at a minimum portion 15m. In this example, the minimum portion 15m is located between the first surface 110 and the second surface 120. In this example, the outline of the through holes 15 when viewed along a direction perpendicular to the first surface 110 is a circle. The diameter of the through holes 15 corresponds to the diameter of this circle. Note that the outline of the through holes 15 may have a shape other than a circle. In this case, the diameter of the through holes 15 is the dimension of the through holes 15 in the direction in which the multiple through holes 15 are arranged.

[0024] The through electrode 100 is disposed inside the through hole 15 so as to electrically connect the first surface 110 side and the second surface 120 side via the through hole 15. The through electrode 100 includes a pad portion 102, a penetrating portion 103, and a blocking portion 105. The blocking portion 105 is a conductor that blocks the through hole 15 on the first surface 110 side. The blocking portion 105 is also referred to as a first portion. A surface (Bs in FIG. 3) of the blocking portion 105 located inside the through hole 15 is located closer to the first surface 110 than the minimum portion 15m. In other words, the minimum portion 15m is not blocked by the blocking portion 105.

[0025] The through portion 103 is a conductor arranged along the inner surface of the through hole 15. The through portion 103 extends continuously from the blocking portion 105 to the second surface 120 side of the through hole 15. The through portion 103 is also referred to as a second portion. The through portion 103 is arranged so as not to block any area (including the minimum portion 15m) inside the through hole 15 other than the blocking portion 105. Therefore, the space 18 surrounded by the through electrode 100 inside the through hole 15 is connected to the space on the second surface 120 side of the glass substrate 11 via the opening 180. Note that, as will be described in other embodiments below, the inside of the space 18 may be filled with another conductor or insulator.

[0026] The pad portion 102 extends continuously from the through portion 103 onto the second surface 120 of the glass substrate 11. A bump 891 is disposed on the pad portion 102.

[0027] [3. Structure of the occlusion section] Next, the detailed structure of the blocking portion 105 will be described with reference to FIG.

[0028] FIG. 3 is a diagram for explaining the structure (blocking portion) on the first surface side of the through electrode in the first embodiment of the present disclosure. FIG. 3 is an enlarged view showing the vicinity of the blocking portion 105 in FIG. 2. First, each part will be defined using FIG. 3. Ts is the surface of the blocking portion 105 on the first surface 110 side. The surface Ts is, in this example, located substantially on the same surface as the first surface 110 of the glass substrate 11. The wiring layer 720 in FIG. 2 contacts the surface Ts. In this example, this contact region is surrounded by the outer edge on the first surface 110 of the through hole 15 as shown in FIG. 2 when viewed along the direction perpendicular to the first surface 110. Although not shown, the contact region may overlap the through hole 15 but not be surrounded by the outer edge of the through hole 15. This contact region is defined by the opening to the blocking portion 105 formed in the interlayer insulating layer 710. Note that the surface Ts may be located inside the through hole 15 rather than the first surface 110 of the glass substrate 11, or may be located outside the through hole 15.

[0029] Bs is the surface of the blocking portion 105 on the second surface 120 side (inside the through hole 15). Vs virtually indicates the position of the conductor before the blocking portion 105 is formed (at the manufacturing stage of FIG. 7). The central axis ac corresponds to the center of the circle when the through hole 15 is viewed perpendicular to the first surface 110. dc corresponds to the diameter of the through hole 15 on the first surface 110. dc1 and dc2 indicate the distances from the central axis ac to positions P1 and P2, and are defined such that dc1 < dc2.

[0030] da is the thickness of the thinnest part among the thicknesses of the closing portion 105 along the direction perpendicular to the first surface 110 (hereinafter simply referred to as "the thickness of the closing portion 105"). In this example, the thinnest part of the thickness of the closing portion 105 is located at the position corresponding to the central axis ac. Therefore, da can also be said to be the thickness of the closing portion 105 at the central axis ac. da1 is the thickness of the closing portion 105 at a position separated from the central axis ac by the distance dc1 in the in-plane direction of the first surface 110. da2 is the thickness of the closing portion 105 at a position separated from the central axis ac by the distance dc2 in the in-plane direction of the first surface 110. db corresponds to the thickness of the thinnest part of the through electrode 100 inside the through hole 15. That is, db corresponds to the thickness of the thinnest part in the through portion 103.

[0031] The position of the thinnest part of the through portion 103 in the direction perpendicular to the first surface 110 is not limited. For example, the thinnest part of the through portion 103 may be located at the minimum portion 15m, may be located closer to the first surface 110 than the minimum portion 15m, or may be located closer to the second surface 120 than the minimum portion 15m.

[0032] The structure of the closing portion 105 is determined to have the following relationships R1 to R3. R1: da < dc < da + db × 2 R2: The closing portion 105 includes a portion where the thickness of the closing portion 105 gradually increases as it moves away from the central axis ac (In this example, da < da1 < da2, and the change in thickness is continuous) R3: When viewed in a cross-section including the central axis ac, the portion of the surface Bs where the closing portion 105 is thinnest has a greater curvature than other portions

[0033] In the example of FIG. 3, since da < da1 < da2, the change in thickness defined by the relationship R2 occurs continuously. The relationship R3 can be rephrased as "when viewed in a cross-section including the central axis ac, the surface Bs has the maximum curvature at the thinnest part of the closing portion 105".

[0034] Here, by making the through electrode 100 a conformal electrode, that is, by forming the through electrode 100 such that a space 18 is disposed inside the through hole 15, the manufacturing cost can be reduced or the stress can be reduced. Further, since the through electrode 100 has a blocking portion 105, it is possible to electrically connect the surface Ts of the through electrode 100 to the wiring layer 720 at a position overlapping the through hole 15.

[0035] In the example shown in FIG. 3, the structure of the blocking portion 105 satisfies all the conditions of the relationships R1 to R3, but it may also be a structure that satisfies only any one of the conditions, or a structure that satisfies a combination of two conditions (not satisfying any one of the three conditions). Further, in the relationship R2, the change in thickness in the order of the central axis ac, the position P1, and the position P2 is not limited to being continuous throughout the entire region, and it may be continuous in a part thereof. By satisfying at least one of the conditions of the relationships R1 to R3, the blocking portion 105 can have a strong holding force against the force directed from the surface Ts side toward the inside of the through hole 15. In this example, since the through hole 15 includes a minimum portion 15m, the blocking portion 105 has an even stronger holding force against the force directed from the surface Ts side toward the inside of the through hole 15. Therefore, high stability can be obtained in the connection between the surface Ts and the wiring layer 720. In particular, since the surface Bs of the blocking portion 105 has a substantially arch-shaped structure, it can have an even stronger holding force.

[0036] The relationships R1 to R3 will be described in detail.

[0037] The "da < dc" in the relationship R1 will be described. In the process of connecting a wiring laminate 70, a printed wiring board 91, an electronic device 92, etc. to the through electrodes 100 of the through electrode substrate 10, the through electrode substrate 10 is heated. When the through electrode substrate 10 is heated, the through electrodes 100 thermally expand. If the coefficient of thermal expansion of the through electrodes 100 is different from that of the substrate 11, internal stress due to thermal expansion occurs in the through electrodes 100. The greater the internal stress, the more likely defects such as cracks and peeling will occur. Cracks occur, for example, in the substrate 11. Peeling occurs, for example, between the blocking portion 105 and the substrate 11. When "da < dc" is satisfied, it becomes easier to relieve the internal stress generated in the blocking portion 105 of the through electrode 100 at the surface Ts. Thereby, defects such as cracks and peeling can be suppressed. For this reason, the blocking portion 105 can withstand the force directed from the surface Ts side toward the inside of the through hole 15.

[0038] The "dc < da + db × 2" in the relationship R1 will be described. When the coefficient of thermal expansion of the through portion 103 of the through electrode 100 is different from that of the substrate 11, internal stress due to thermal expansion occurs in the through portion 103. The thinner the thickness of the through portion 103, the more likely the through portion 103 is to peel off from the inner surface of the through hole 15 due to the internal stress. By setting the thickness of the thinnest part of the through portion 103 so that "dc < da + db × 2" is satisfied, it is possible to suppress the through portion 103 from peeling off from the inner surface of the through hole 15.

[0039] As the values of dc, da, and db in the relationship R1, the average values of the measured values of dc, da, and db in a plurality of through holes 15 and through electrodes 100 are used. For example, the average values of the measured values of dc, da, and db in 50 or more through holes 15 and through electrodes 100 are used.

[0040] The measurement method for measuring dc, da, and db will be described. First, as shown in FIG. 44A, a preparation process of preparing a sample of the through electrode substrate 10 having a width W is performed. The width W of the sample is, for example, 500 μm or more and 1 mm or less. The sample includes a plurality of, for example, 5 or more through holes 15 arranged in the width direction.

[0041] Next, a cutting step is performed in which the sample is cut by ion polishing along the cutting line E1-E1 shown in Figure 44A. In the cutting step, the sample is cut so that the cutting line E1-E1 passes through all of the through holes 15 lined up in the width direction. Preferably, the cutting line E1-E1 passes through the center of the through hole 15 located at the center in the width direction. Figure 44B is a cross-sectional view of the through electrode substrate of Figure 44A cut along the line E1-E1.

[0042] Next, a selection step is performed to select the through hole 15 having the largest diameter dc. In the example shown in FIG. 44B, the through hole 15 located at the center in the width direction has the largest diameter dc. Next, a measurement step is performed to measure da and db of the through electrode 100 provided in the through hole 15 having the largest diameter dc. In this manner, the measured values of dc, da, and db for one through hole 15 and through electrode 100 can be obtained. By performing the preparation step, cutting step, selection step, and measurement step 50 times, the measured values of dc, da, and db for 50 or more through holes 15 and through electrodes 100 can be obtained. A scanning electron microscope (SEM) manufactured by JEOL can be used as a measuring instrument to measure dimensions such as dc, da, and db.

[0043] Fig. 45A is a plan view showing another example of a sample of a through hole electrode substrate. As shown in Fig. 45A, in the cutting process, the cutting line E2-E2 may not pass through the center of through hole 15 located in the center in the width direction. In this case, as shown in Fig. 45B, the diameters dc of the multiple through holes 15 that appear in the cross-sectional view are different from one another. Fig. 45B is a cross-sectional view of the through hole electrode substrate of Fig. 45A cut along line E2-E2.

[0044] 44B, a selection step is also carried out to select the through hole 15 having the largest diameter dc. In the example shown in Fig. 45B, the second through hole 15 from the right in the figure has the largest diameter dc. Subsequently, a measurement step is carried out to measure da and db of the through electrode 100 provided in the through hole 15 having the largest diameter dc.

[0045] According to the above-described measurement method, even if the cutting line of the sample deviates from the ideal in the cutting process, the through hole 15 to be measured can be appropriately selected. Therefore, the variations in the measured values of dc, da, and db can be suppressed.

[0046] The relationship R2 will be explained. In the blocking portion 105 that satisfies the relationship R2, the surface Bs on the inner side of the through hole 15 includes a portion that approaches the second surface 120 as it moves away from the central axis ac. This allows the surface Bs of the blocking portion 105 to have an arched structure. In this case, when the blocking portion 105 receives a force directed from the surface Ts side toward the inside of the through hole 15, a compressive force is generated on the surface Bs. This allows the blocking portion 105 to withstand the force directed from the surface Ts side toward the inside of the through hole 15.

[0047] The relationship R3 will now be explained. When the surface Bs of the blocking portion 105 has an arched structure, the greater the curvature of the surface Bs, the more the force generated inside the blocking portion 105 can be dispersed. The force generated inside the blocking portion 105 tends to become larger the closer it is to the central axis ac. In the blocking portion 105 that satisfies the relationship R3, the surface Bs has the greatest curvature at the thinnest portion of the blocking portion 105. The thinnest portion of the blocking portion 105 overlaps with the central axis ac or is close to the central axis ac. By satisfying the relationship R3, the force generated at the thinnest portion of the blocking portion 105 is easily dispersed to the surrounding area. This makes it possible to prevent defects such as cracks from occurring in the thinnest portion of the blocking portion 105.

[0048] 3, the thickness db of the thinnest portion of the penetrating portion 103 is smaller than the thickness da of the thinnest portion of the blocking portion 105. db / da is, for example, 1 / 4 or less, and may be 1 / 5 or less. db / da is, for example, 1 / 10 or more, and may be 1 / 9 or more.

[0049] [4. Manufacturing method of through-hole electrode substrate] Next, a method for manufacturing the above-mentioned through hole electrode substrate 10 will be described with reference to FIGS.

[0050] 4 to 11 are diagrams illustrating a method for manufacturing a through hole electrode substrate according to the first embodiment of the present disclosure. First, as shown in FIG. 4, a glass substrate 11 is prepared, and through holes 15 are formed in the glass substrate 11. The thickness of a substrate such as the glass substrate 11 is, for example, 100 μm or more, and may be 200 μm or more. The thickness of the substrate is, for example, 1 mm or less, and may be 500 μm or less. In this example, the thickness of the glass substrate 11 is 400 μm. Instead of the glass substrate 11, a substrate formed of another inorganic material such as a quartz substrate, silicon wafer, or ceramic may be used, or a substrate formed of an organic material such as a resin substrate may be used. When a conductive substrate such as a silicon wafer is used, the surface of the substrate, including the inner surfaces of the through holes 15, is covered with an insulator after the through holes 15 are formed.

[0051] The through holes 15 are formed so as to penetrate between the first surface 110 and the second surface 120 by irradiating the glass substrate 11 with a laser under predetermined conditions and then performing an etching process with a predetermined etching solution. The maximum diameter of the through holes 15 is, for example, 25 μm or more and 50 μm or less. Meanwhile, in this example, the diameter of the through holes 15 has a minimum value at approximately the center of the glass substrate 11. The minimum value is, for example, 10 μm or more and 30 μm or less. The minimum value of the diameter of the through holes 15 may be 40% or more and 60% or less of the maximum diameter of the through holes 15.

[0052] Next, as shown in FIG. 5 , a first metal layer 100a is formed on the first surface 110, the second surface 120, and the inner surfaces of the through holes 15 of the glass substrate 11. The first metal layer 100a functions as a seed layer in the process of forming the second metal layer 100b by electrolytic plating, which will be described later. In this example, the first metal layer 100a is Cu formed by electroless plating. The first metal layer 100a is preferably deposited to a thickness of 0.1 μm to 3 μm, and in this example, it is deposited to a thickness of 0.3 μm. Note that the first metal layer 100a may be any metal that functions as a seed layer for electrolytic plating. For example, the first metal layer 100a may be a metal containing Ti, Ni, Cr, Ti, W, or the like, or may be a laminate of different metals. The seed layer may be formed not only by electroless plating but also by sputtering. Although not shown, before the formation of the first metal layer 100a, an adhesion layer may be formed on the first surface 110, the second surface 120, and the inner surfaces of the through holes 15 of the glass substrate 11. The adhesion of the adhesion layer to the glass substrate 11 is higher than the adhesion of the first metal layer 100a to the glass substrate 11. An example of a material constituting the adhesion layer is a metal oxide such as zinc oxide.

[0053] 6, a resist mask RM is formed on a predetermined region of the first metal layer 100a on the second surface 120 side of the glass substrate 11. Next, an electrolytic plating process is performed to grow a second metal layer 100b by electroplating in the region other than the region where the resist mask RM is formed, i.e., the region where the first metal layer 100a is exposed. The electrolytic plating process includes a first electrolytic plating process in which the second metal layer 100b is formed under first conditions, and a second electrolytic plating process in which the second metal layer 100b is formed under second conditions that are changed from the first conditions.

[0054] 7 is a diagram showing the first electrolytic plating step. The first condition is set so that the growth rate of second metal layer 100b on the first surface 110 side and the growth rate of second metal layer 100b on the second surface 120 side are substantially the same. 8 is a diagram showing the second electrolytic plating step. The second conditions are set so that the growth rate of second metal layer 100b on the first surface 110 side is greater than the growth rate of second metal layer 100b on the second surface 120 side. For example, the electrolytic plating process may be performed in an environment where the plating solution is more concentrated on the first surface 110 side than on the second surface 120 side. The electrolytic plating process may also be performed in an environment where the current supplied to through hole 15 is greater on the first surface 110 side than on the second surface 120 side.

[0055] By this process, the area CA of the through hole 15 on the first surface 110 side is blocked by the second metal layer 100b. Meanwhile, a space 18 surrounded by the second metal layer 100b is formed in the area of the through hole 15 other than the area CA. In the portion of the through hole 15 that becomes the minimum portion 15m, the diameter of the space 18 is preferably 10% to 50% of the diameter dcm of the minimum portion 15m. That is, the combined thickness de of the first metal layer 100a and the second metal layer 100b in the minimum portion 15m is preferably 25% to 45% of the diameter dcm. In this example, the first metal layer 100a and the second metal layer 100b are formed so that the thickness de is approximately 30% of the minimum diameter dcm of the through hole 15. The space 18 and the space on the second surface 120 side of the glass substrate 11 are connected via an opening 180. The second metal layer 100b is, for example, Cu. The second metal layer 100b may be a metal containing Au, Ag, Pt, Al, Ni, Cr, Sn, or the like.

[0056] Because the through holes 15 remain open until they are blocked by the blocking portions 105, it is also possible to pass a plating solution through the through holes 15. According to this manufacturing method, the blocking portions 105 are formed last, and therefore the second metal layer 100b can also be formed stably.

[0057] An example of the first electrolytic plating step and the second electrolytic plating step will be described in detail with reference to FIGS. 30A to 30D.

[0058] The plating solution used in the first electrolytic plating step contains, for example, copper sulfate pentahydrate and sulfuric acid. Copper sulfate pentahydrate has the molecular formula CuSO4·5H2O. Sulfuric acid has the molecular formula H2SO4. The weight percentage of copper sulfate pentahydrate in the plating solution is also referred to as the first ratio L1. The weight percentage of sulfuric acid in the plating solution is also referred to as the second ratio L2. In the plating solution for the first electrolytic plating step, the second ratio L2 is preferably greater than the first ratio L1. This reduces the difference between the Cu concentration of the plating solution on the first surface 110 or the second surface 120 of the glass substrate 11 and the Cu concentration of the plating solution inside the through hole 15.

[0059] FIG. 30A is a diagram illustrating an example of a first electrolytic plating process. As shown in FIG. 30A, current may be supplied to through-hole 15 from the first surface 110 side and the second surface 120 side of glass substrate 11. The current supplied to through-hole 15 from the first surface 110 side is also referred to as first current i1. The current supplied to through-hole 15 from the second surface 120 side is also referred to as second current i2. In the first electrolytic plating process, it is preferable that the difference between first current i1 and second current i2 is small. For example, first current i1 is 0.8 to 1.2 times the second current i2. This can prevent differences in the growth rate of second metal layer 100b from occurring on first surface 110, second surface 120, and inside through-hole 15.

[0060] The plating solution used in the second electrolytic plating step may contain copper sulfate pentahydrate and sulfuric acid, as in the first electrolytic plating step. In the plating solution used in the second electrolytic plating step, the first ratio L1 is preferably greater than the second ratio L2. This allows the Cu concentration in the plating solution on the first surface 110 or the second surface 120 of the glass substrate 11 to be higher than the Cu concentration in the plating solution inside the through holes 15.

[0061] 30B to 30D are diagrams illustrating an example of the second electrolytic plating step. As shown in FIG. 30B, in the second electrolytic plating step, the first current i1 is preferably greater than the second current i2. For example, the first current i1 is greater than 1.5 times the second current i2. This allows the growth rate of the second metal layer 100b on the first surface 110 to be greater than the growth rate of the second metal layer 100b on the second surface 120. The first current i1 may be 2.0 times or more, 3.0 times or more, or 5.0 times or more the second current i2. The first current i1 may be 5.0 times or less the second current i2.

[0062] The end of through hole 15 on the first surface 110 side is also referred to as first end 16, and the end of through hole 15 on the second surface 120 side is also referred to as second end 17. When the first ratio L1 in the plating solution is greater than the second ratio L2, or when the first current i1 is greater than the second current i2, the growth rate of second metal layer 100b at first end 16 can be made greater than the growth rate of second metal layer 100b at second end 17, as shown in FIG. 30C. For example, the cross section of second metal layer 100b can partially have a circular shape centered on first end 16, as shown in FIG. 30C.

[0063] When the first current i1 is greater than the second current i2, the growth rate of the second metal layer 100b located on the inner surface of the through hole 15 increases the closer it is to the first surface 110. For this reason, as shown in Fig. 30C, the thickness of the second metal layer 100b located on the inner surface of the through hole 15 decreases toward the second surface 120. As a result, the surface Bs of the second metal layer 100b formed around the first end 16 on the inner side of the through hole 15 approaches the second surface 120 the further it is from the central axis ac.

[0064] 30D, second metal layer 100b grown around each position of first end 16 of through hole 15 joins together, so that second metal layer 100b can close through hole 15 on the first surface 110 side. In this way, closing portion 105 including second metal layer 100b is obtained.

[0065] The growth rate of second metal layer 100b located on the inner surface of through hole 15 decreases with increasing distance from the inner surface. Therefore, the curvature of surface Bs of portion of blocked portion 105 overlapping central axis ac tends to be maximized.

[0066] The position and shape of the surface Bs of the blocking portion 105 can be changed by adjusting the first current i1 and the second current i2. Alternatively, the position and shape of the surface Bs of the blocking portion 105 can be changed by adjusting the first ratio L1 and the second ratio L2. FIG. 31 is a cross-sectional view showing the blocking portion 105 obtained when the ratio of the first current i1 to the second current i2 is increased compared to the examples shown in FIGS. 30B to 30D. As shown in FIG. 31, by increasing the difference between the first current i1 and the second current i2, the position of the surface Bs of the blocking portion 105 can be shifted toward the second surface 120. Furthermore, by increasing the difference between the first current i1 and the second current i2, the radius of curvature of the surface Bs at the thinnest portion of the blocking portion 105 can be reduced.

[0067] Next, as shown in Fig. 9, the resist mask RM is removed. Next, as shown in Fig. 10, the first metal layer 100a and the second metal layer 100b on the first surface 110 side of the glass substrate 11 are removed by, for example, CMP (Chemical Mechanical Polishing) processing to expose the first surface 110. Note that the first metal layer 100a and the second metal layer 100b may be removed by other processing such as wet etching, grinding using a fly cutter, or physical mechanical polishing. The processing of Fig. 10 may be performed before the processing of Fig. 9.

[0068] 11, the first metal layer 100a is removed from the second surface 120 of the glass substrate 11 using the second metal layer 100b as a mask. In this manner, the through electrode substrate 10 having the through electrodes 100 arranged therein is manufactured from the glass substrate 11. The process of FIG. 11 may be performed before the process of FIG. 10. Note that in FIG. 2, the through electrode 100 is shown as a conductor combining the first metal layer 100a and the second metal layer 100b.

[0069] [Example] Fig. 12 is an electron microscope photograph of a cross section of a through electrode. The electron microscope photograph shown in Fig. 12 is a cross section of a through electrode 100 manufactured by the above-described manufacturing method of a through electrode substrate 10. This cross section is a plane cut so as to include the central axis of the through hole 15. As shown in Fig. 12, a structure having a blocked portion 105 in the through electrode 100 can be realized.

[0070] Second Embodiment The through electrodes in the second embodiment are manufactured by a method different from that in the first embodiment described above.

[0071] 13 to 15 are diagrams illustrating a method for manufacturing a through hole electrode substrate according to a second embodiment of the present disclosure. In the second embodiment, as shown in Fig. 13, after forming a first metal layer 100a as in Fig. 5 of the first embodiment, a second metal layer 100b shown in Figs. 7 and 8 is formed without forming a resist mask RM shown in Fig. 6. In this state, as shown in Fig. 14, the first metal layer 100a and the second metal layer 100b are removed by CMP processing on both the first surface 110 side and the second surface 120 side of the glass substrate 11, thereby exposing both surfaces of the glass substrate 11.

[0072] Next, as shown in FIG. 15, a third metal layer 100c serving as a seed layer is formed on the second surface 120 side by sputtering. A resist mask RM is then formed on a portion of the third metal layer 100c. In FIG. 15, the third metal layer 100c is formed only on the second surface 120. Although not shown, a portion of the third metal layer 100c may also be formed on the second metal layer 100b inside the through hole 15. A metal layer is then grown on the third metal layer 100c by electrolytic plating. The resist mask RM is then removed, and any unnecessary metal layer is removed. This results in a through electrode 100 having a structure similar to that shown in FIG. 2. By performing electrolytic plating under conditions that facilitate growth of a metal layer on the second surface 120 side, i.e., on the third metal layer 100c (conditions different from those used to grow the second metal layer 100b), the thickness of the pad portion 102 made of a metal layer on the second surface 120 can be made thicker than the thickness of the through portion 103. The unnecessary metal layer refers to the third metal layer 100c in the portion that was covered with the resist mask RM. Depending on the conditions of the electrolytic plating process, a metal layer may also be formed on the first surface 110 side from the region of the through hole 15. In this case, the metal layer on the first surface 110 side may also be removed.

[0073] <Third embodiment> The through electrodes in the third embodiment are manufactured by a method different from that in the first embodiment described above.

[0074] 16 to 18 are diagrams illustrating a method for manufacturing a through hole electrode substrate according to a third embodiment of the present disclosure. In the third embodiment, when a resist mask RM is formed as in FIG. 7 of the first embodiment, a resist mask RM is also formed on the first surface 110 side to cover the first metal layer 100a in a portion away from the through hole 15. Thereafter, as shown in FIG. 16, a second metal layer 100b is grown by an electrolytic plating process under first conditions. Then, as shown in FIG. 17, a second metal layer 100b is further grown by an electrolytic plating process under second conditions. As a result, the region CA of the through hole 15 is blocked by the second metal layer 100b. By forming the resist mask RM on the first surface 110 side, the region on the first surface 110 where the second metal layer 100b grows can be limited. Therefore, the second metal layer 100b grows in a shorter time. Therefore, an efficient electrolytic plating process is achieved. Then, as shown in FIG. 18, the resist mask RM is removed. Thereafter, the first metal layer 100a and the second metal layer 100b protruding from the through hole 15 toward the first surface 110 are removed by CMP or the like, thereby obtaining the through electrode 100 having the same structure as that shown in FIG.

[0075] <Fourth embodiment> The through hole 15 in the first embodiment described above is located between the first surface 110 and the second surface 120 and has a minimum portion 15m where the diameter of the through hole 15 is minimum. In the fourth embodiment, a through hole 15A having a shape different from that of the through hole 15 in the first embodiment is formed in the glass substrate 11. Specifically, the through hole 15A in the fourth embodiment does not have this minimum portion 15m.

[0076] FIG. 19 is a diagram illustrating a cross-sectional structure of a through electrode according to the fourth embodiment of the present disclosure. A through hole 15A is formed in the glass substrate 11. The through hole 15A has a shape in which the diameter increases from the first surface 110 side toward the second surface 120 side. The through hole 15A is formed, for example, by sandblasting the glass substrate 11 from the second surface 120 side. The through hole 15A may be formed by irradiating the glass substrate 11 with a laser under predetermined conditions, followed by etching with a predetermined etching solution. The through electrode 100A includes a pad portion 102A, a penetrating portion 103A, and a blocking portion 105A. The blocking portion 105A is arranged to block the first surface 110 side of the through hole 15A, i.e., the side of the through hole 15A with a smaller diameter. A space 18A surrounded by the through electrode 100A inside the through hole 15A is arranged to be connected to the space on the second surface 120 side of the glass substrate 11 via an opening 180A. 19 and 20, similarly to FIG. 2, the through electrode 100 is shown as a conductor that combines the first metal layer 100a and the second metal layer 100b.

[0077] 20 is a diagram illustrating the structure (blocking portion) of the first surface side of the through electrode in the fourth embodiment of the present disclosure. The structure of the blocking portion 105A is also similar to the structure of the blocking portion 105 in the first embodiment. When each part is defined as shown in FIG. 20, the structure of the blocking portion 105A also satisfies at least one of the conditions of the relationships R1 to R3. In the example shown in FIG. 20, the structure of the blocking portion 105A satisfies all of the conditions of the relationships R1 to R3. Due to the difference in the shape of the through hole, the rate of increase from da to da1 to da2 is smaller in the blocking portion 105A than in the blocking portion 105. However, even in the blocking portion 105A, a strong holding force can be exerted against a force from the surface Ts side toward the inside of the through hole 15.

[0078] Fifth Embodiment In the fifth embodiment, a through electrode 100B in which a filler is placed in the space 18 formed in the through hole 15 in the first embodiment will be described.

[0079] FIG. 21 is a diagram illustrating a cross-sectional structure of a through electrode according to a fifth embodiment of the present disclosure. First, the glass substrate 11 and through electrode 100 in the state shown in FIG. 11 according to the first embodiment are prepared. Next, as shown in FIG. 21, a filler 109 is placed in the space 18 through the opening 180. The filler 109 is formed by flowing as a fluid from the opening 180 into the space 18 and then solidifying. In this example, the filler 109 may be formed of an insulating material or a conductive material such as a metal paste. Examples of insulating materials include organic resins and inorganic compounds. Examples of organic resins include polyimide and acrylic. Examples of inorganic compounds include silicon oxide. The filler 109 may contain both an organic resin and an inorganic compound. An example of a metal paste is a paste containing Cu, Ni, Ag, Au, or the like. The material flowed into the space 18 through the opening 180 to form the filler 109 may or may not be photosensitive. By forming the filler 109 from the above material, it is possible to reduce manufacturing costs and stress caused by the through electrode compared to when the space 18 is filled with the second metal layer 100b by electrolytic plating. Although not shown, a space such as a void may exist inside the filler 109 or between the filler 109 and the substrate 11 as long as the reliability of the through electrode substrate 10 is maintained.

[0080] 21, the surface Fs of the filler 109 is located so as to be flush with the second metal layer 100b on the second surface 120 side. Although not shown, the surface Fs may be located so as not to be flush with the second metal layer 100b. That is, the surface Fs may be located so as to form the same plane as the second surface 120, may be located inside the through hole 15, or may be located so as to protrude beyond the second metal layer 100b.

[0081] Sixth Embodiment In the case where the filler 109 in the fifth embodiment is a conductor, the through electrode 100B can also be connected to the wiring layer on the second surface 120 at a position overlapping the through hole 15. In the sixth embodiment, an example of the through electrode 100C in the case where the filler 109 is made of a conductive material will be described.

[0082] 22 is a diagram illustrating a cross-sectional structure of a through electrode according to a sixth embodiment of the present disclosure. The through electrode 100C shown in FIG. 22 further includes a filler 109 disposed inside the through electrode in the state shown in FIG. 14 according to the second embodiment. The filler 109 is a conductor. The through electrode 100C includes a blocking portion 105 including a second metal layer 100b exposed from the through hole 15 on the first surface 110 side, and a filler 109C exposed from the through hole 15 on the second surface 120 side. Meanwhile, the first surface 110 and the second surface 120 of the glass substrate 11 are exposed in areas other than the through hole 15.

[0083] FIG. 23 is a diagram illustrating a cross-sectional structure of a wiring substrate according to a sixth embodiment of the present disclosure. A wiring substrate 80C shown in FIG. 23 includes, in addition to the wiring substrate 80 according to the first embodiment, a wiring stack 70C disposed on the second surface 120 side of the glass substrate 11. A wiring layer 720C in the wiring stack 70C is connected to a filler 109C in the through electrode 100C. The wiring layer 720C in FIG. 23 contacts a surface Fs of the filler 109. In this example, the contact region where the surface Fs of the filler 109 and the wiring layer 720C contact each other is surrounded by the outer edge of the through hole 15 on the second surface 120 when viewed along a direction perpendicular to the second surface 120, as shown in FIG. 23. Although not shown, the contact region may overlap with the through hole 15 but not be surrounded by the outer edge of the through hole 15. This contact region is defined by an opening formed in an interlayer insulating layer 710C. In the opening, a wiring layer 720C connected to the filler 109C is disposed. Although not shown in the figure, a pad to be connected to a bump may be formed on the surface of the wiring stack 70C opposite to the glass substrate 11.

[0084] Seventh Embodiment In the seventh embodiment, an example of applying the structure of the through electrode 100C in the sixth embodiment to the through electrode 100A in the fourth embodiment shown in FIG. 19 will be described.

[0085] FIG. 24 is a diagram for explaining the cross-sectional structure of the through electrode in the seventh embodiment of the present disclosure. The through electrode 100D shown in FIG. 24 is the same as the through electrode 100A shown in FIG. 19 in the fourth embodiment, except for the following points. · The pad portion 102A is not provided. · The filler 109 is disposed inside the through electrode. The through electrode 100D shown in FIG. 24 includes a closing portion 105A including a second metal layer 100b exposed from the through hole 15A on the first surface 110 side, and a filler 109D exposed from the through hole 15A on the second surface 120 side. On the other hand, on portions other than the through hole 15A, the first surface 110 and the second surface 120 of the glass substrate 11 are exposed. With such a structure, similar to the case of the sixth embodiment, the wiring layer can be connected to the filler 109D without using the pad portion 102A.

[0086] <Eighth Embodiment> In the eighth embodiment, another method for manufacturing a through electrode that realizes the relationship R1 (da < dc < da + db × 2) will be described.

[0087] 25 to 28 are diagrams illustrating a manufacturing method of a through hole electrode substrate according to an eighth embodiment of the present disclosure. First, holes are formed in the glass substrate 11 from the second surface 120 side by sandblasting or the like. Alternatively, holes may be formed by irradiating the glass substrate 11 with a laser under predetermined conditions and then etching with a predetermined etching solution. As shown in FIG. 25, holes 150E are formed that do not penetrate all the way to the first surface 110 side. The holes 150E have bottoms located on the first surface 110 side. Such holes are also referred to as bottomed holes. Next, as shown in FIG. 26, a first metal layer 100a serving as a seed layer is formed from the second surface 120 side by sputtering, a resist mask RM is formed, and a second metal layer 100b is formed by electroplating. The electroplating here uses conditions that result in a relatively slow growth rate on the front surface side of the glass substrate 11. For example, a plating solution containing an additive is used. As a result, a portion BP of second metal layer 100b on the bottom side of bottomed hole 150E is thicker than other portions of second metal layer 100b. Inside bottomed hole 150E, space 18E surrounded by second metal layer 100b is arranged so as to be connected to a space on second surface 120 side of glass substrate 11 via opening 180E.

[0088] Next, the resist mask RM is removed. Next, as shown in FIG. 27, the first metal layer 100a is removed from the portion where the resist mask RM was disposed. Thereafter, as shown in FIG. 28, the first surface 110 side of the glass substrate 11 is etched by CMP processing or the like to expose the second metal layer 100b on the first surface 110 side. This removes the bottom of the bottomed hole 150E, thereby forming the through hole 15E. Note that the first metal layer 100a may be exposed on the first surface 110 side by etching so as to leave it.

[0089] This results in the formation of a through electrode 100E having a structure similar to that of the through electrode 100A of the fourth embodiment shown in Fig. 19. Fig. 28 shows the parameters that define the relationship R1. Here, da is shown as the thickness on the central axis ac. The through electrode 100A has a structure that satisfies all of the relationships R1, R2, and R3, but the through electrode 100E has a structure that satisfies only the relationship R1.

[0090] Ninth Embodiment The above-described electronic unit 1000 is mounted on various electrical devices such as mobile terminals (mobile phones, smartphones, notebook personal computers, etc.), information processing devices (desktop personal computers, servers, car navigation systems, etc.), and home appliances.

[0091] FIG. 29 is a diagram illustrating an electronic device including an electronic unit according to the first embodiment of the present disclosure. The electronic unit 1000 is mounted in various electrical devices, such as mobile terminals (such as mobile phones, smartphones, and laptop computers), information processing devices (such as desktop personal computers, servers, and car navigation systems), and home appliances. A smartphone 500 and a laptop personal computer 600 are shown as examples of electrical devices equipped with the electronic unit 1000. These electrical devices have a control unit 1100 configured with a CPU or the like that executes application programs to realize various functions. The various functions include a function that uses an output signal from the electronic unit 1000. The electronic unit 1000 may also have the functions of the control unit 1100.

[0092] Tenth Embodiment 32, the radius of curvature ra of the surface Bs of the thinnest part of the blocked portion 105 of the through electrode 100 will be described. The radius of curvature ra is the reciprocal of the curvature of the surface Bs of the thinnest part of the blocked portion 105.

[0093] The radius of curvature ra may be defined as the ratio of the radius rb of the through-hole 15 on the first surface 110. ra / rb is preferably 0.2 or greater. This prevents excessive compressive force from being generated on the surface Bs of the thinnest part of the blocking portion 105 when the blocking portion 105 is pressed. This prevents defects such as cracks from occurring in the thinnest part of the blocking portion 105. ra / rb may be 0.4 or greater, or may be 0.6 or greater.

[0094] On the other hand, if ra / rb is too large, the compressive force generated in the blocking portion 105 when the blocking portion 105 is pressed cannot be dispersed appropriately to the surroundings, which may result in destruction of the blocking portion 105. In consideration of this point, ra / rb is preferably 1.5 or less. ra / rb may be 1.3 or less, or may be 1.1 or less.

[0095] Appropriately setting the thickness da of the thinnest portion of the blocking portion 105 is also effective as a means of suppressing defects such as cracks. The thickness da is preferably 10 μm or more. This ensures the mechanical strength of the thinnest portion of the blocking portion 105. The thickness da may be 20 μm or more, or may be 30 μm or more. On the other hand, if the thickness da is excessively large, the internal stress generated in the blocking portion 105 is difficult to relieve at the surface Ts. In this case, destruction of the blocking portion 105, cracks in the substrate 11, etc. may occur. In consideration of this, the thickness da is preferably 100 μm or less. The thickness da may be 80 μm or less, or may be 60 μm or less.

[0096] Eleventh Embodiment In the eleventh embodiment, an example of electrically connecting the through electrodes 100 of the through electrode substrate 10 and the electronic device 92 will be described with reference to Figs. 33 to 35. Specifically, a method of electrically connecting the through electrodes 100 and the electrodes of the electronic device 92 by heating the electronic device 92 while applying pressure toward the through electrode substrate 10 to the electronic device 92 will be described. This method is also called TCB (Thermal Compression Bonding).

[0097] 33 , the electronic device 92 includes a first surface 925, a second surface 926, and an electrode 922 located on the first surface 925. The electrode 922 may include a pad. The electrode 922 may include a pad and a pillar located on the pad. A structure of the electrode 922 including a pillar is particularly employed when the pitch P of the electrodes 922 is small. The pitch P is, for example, 100 μm or less. Bumps 892 may be provided on the electrode 922.

[0098] First, as shown in FIG. 33, a bonding head 200 is attached to the second surface 926 of the electronic device 92. Next, as shown in FIG. 34, the bonding head 200 is moved toward the through-hole electrode substrate 10, thereby bringing the bumps 892 into contact with the blocking portions 105 of the through-hole electrodes 100. The bonding head 200 is then used to heat the electronic device 92. This allows a heating and pressing step to be performed in which the electronic device 92 is heated while pressure toward the through-hole electrode substrate 10 is applied to the electronic device 92. Thereafter, the temperature of the bonding head 200 is maintained constant with the pressure toward the through-hole electrode substrate 10 set to zero or approximately zero. This allows the electrodes 922 to be connected to the blocking portions 105 via the bumps 892, as shown in FIG. 35.

[0099] In order to connect the electrodes 922 to the blocking portion 105 by the heating and pressing process, it is preferable that the force applied to one electrode 922 is equal to or greater than a threshold. The threshold is, for example, 0.001 kgf, but may also be 0.006 kgf or 0.1 kgf. In this case, the blocking portion 105 is required to withstand a force equal to or greater than the threshold.

[0100] In the through hole electrode substrate 10 of the present application, at least one of the above-described relationships R1 to R3 is satisfied, thereby allowing the blocking portion 105 to withstand a force equal to or greater than a threshold value.

[0101] <Twelfth embodiment> In the twelfth embodiment, an example of a structure for electrically connecting the blocking portion 105 of the through hole electrode substrate 10 and the electrode 922 of the electronic device 92 will be described.

[0102] 36, a diffusion prevention film 94 may be provided on an electrode 922 of an electronic device 92. The diffusion prevention film 94 may include, for example, a nickel layer located on the electrode 922 and a gold layer located on the nickel layer. The diffusion prevention film 94 may be formed by electroless plating or electrolytic plating.

[0103] 36, a diffusion prevention film 106 may be provided on the blocking portion 105 of the through-hole electrode substrate 10. Similar to the diffusion prevention film 94, the diffusion prevention film 106 may include a nickel layer located on the blocking portion 105 and a gold layer located on the nickel layer.

[0104] <Thirteenth embodiment> In the thirteenth embodiment, an example of a structure for electrically connecting the blocking portion 105 of the through hole electrode substrate 10 and the electrode 922 of the electronic device 92 will be described.

[0105] 37, an electrode 107 may be provided on the blocking portion 105 of the through hole electrode substrate 10. The electrode 107 may include a pad. The electrode 107 may include a pad and a pillar located on the pad.

[0106] 36, a diffusion prevention film 106 may be provided on the electrode 107. Although not shown, the diffusion prevention film 106 does not have to be provided. Furthermore, like the example of FIG. 36, a diffusion prevention film 94 may be provided on the electrode 922. Although not shown, the diffusion prevention film 94 does not have to be provided.

[0107] <Fourteenth embodiment> In the fourteenth embodiment, an example of a structure for electrically connecting the blocking portion 105 of the through hole electrode substrate 10 and the electrode 922 of the electronic device 92 will be described. As shown in Fig. 38, the electrode 922 of the electronic device 92 may be connected to the blocking portion 105 of the through hole electrode substrate 10 without using a bump. Both the electrode 922 and the blocking portion 105 may contain copper. In this case, the electrode 922 can be connected to the blocking portion 105 using Cu-Cu bonding.

[0108] <Fifteenth embodiment> In the fifteenth embodiment, an example of a structure for electrically connecting the blocking portion 105 of the through hole electrode substrate 10 and the electrode 922 of the electronic device 92 will be described. As shown in Fig. 39, the electrode 922 of the electronic device 92 may be connected to the electrode 107 on the blocking portion 105 of the through hole electrode substrate 10 without using a bump. Both the electrode 922 and the electrode 107 may contain copper. In this case, the electrode 922 can be connected to the electrode 107 by using Cu-Cu bonding.

[0109] <Sixteenth embodiment> In the sixteenth embodiment, an example of the cross-sectional structure of a wiring layer 720 connected to a blocking portion 105 of a through electrode substrate 10 will be described with reference to Fig. 40A and Fig. 40B. Fig. 40A is a cross-sectional view showing the wiring layer. Fig. 40B is a plan view showing the wiring layer. Fig. 40A is a cross-sectional view of the wiring layer taken along line AA in Fig. 40B.

[0110] 40A and 40B, the contact region where the wiring layer 720 and the blocking portion 105 are in contact may include multiple regions. For example, the wiring layer 720 may include wiring 722 extending in the in-plane direction of the first surface 110 of the through hole electrode substrate 10, and multiple connection layers 721 connecting the wiring 722 to the blocking portion 105. As shown in FIG. 40B, when viewed along the direction perpendicular to the first surface 110, the multiple connection layers 721 may be surrounded by the outer edge of the through hole 15 on the first surface 110.

[0111] Seventeenth Embodiment In the seventeenth embodiment, an example of the cross-sectional structure of a wiring layer 720 connected to a blocking portion 105 of a through electrode substrate 10 will be described with reference to Figs. 41A and 41B. Fig. 41A is a cross-sectional view showing the wiring layer. Fig. 41B is a plan view showing the wiring layer. Fig. 41A is a cross-sectional view taken along line BB of the wiring layer in Fig. 41B.

[0112] 40A and 40B, the contact region where the wiring layer 720 and the blocking portion 105 contact each other may include multiple regions. For example, the wiring layer 720 may include wiring 722 extending in the in-plane direction of the first surface 110 of the through electrode substrate 10, and multiple connection layers 721 connecting the wiring 722 to the blocking portion 105. As shown in FIG. 41B, when viewed along a direction perpendicular to the first surface 110, the multiple connection layers 721 may overlap the outer edge of the through hole 15 on the first surface 110.

[0113] <Eighteenth embodiment> In the eighteenth embodiment, an example of the cross-sectional structure of a wiring layer 720 connected to a blocking portion 105 of a through electrode substrate 10 will be described with reference to Fig. 42A and Fig. 42B. Fig. 42A is a cross-sectional view showing the wiring layer. Fig. 42B is a plan view showing the wiring layer. Fig. 42A is a cross-sectional view taken along line CC of the wiring layer in Fig. 42B.

[0114] 42A and 42B , when viewed along a direction perpendicular to the first surface 110, a contact region where the wiring layer 720 and the blocking portion 105 are in contact may surround the outer edge of the through-hole 15 on the first surface 110. For example, the wiring layer 720 may include a wiring 722 that extends in the in-plane direction of the first surface 110 of the through-hole electrode substrate 10. The wiring 722 may have a width w1 that is larger than a diameter dc of the through-hole 15 on the first surface 110.

[0115] <Nineteenth embodiment> In the nineteenth embodiment, an example of the cross-sectional structure of a wiring layer 720 connected to a blocking portion 105 of a through electrode substrate 10 will be described with reference to Fig. 43A and Fig. 43B. Fig. 43A is a cross-sectional view showing the wiring layer. Fig. 43B is a plan view showing the wiring layer. Fig. 43A is a cross-sectional view taken along line DD of the wiring layer in Fig. 43B.

[0116] 43A and 43B, the wiring layer 720 may include wiring 722 that is connected to the blocking portion 105 and extends in the in-plane direction of the first surface 110. For example, the wiring layer 720 may include a plurality of wirings 722 that are connected to the blocking portion 105 and extend in different directions from each other.

[0117] Although one embodiment of the present invention has been described above, the above-described embodiments can be applied by combining or replacing each other. Furthermore, the above-described embodiments can also be modified as follows. For example, even when a through electrode 100A in the fourth embodiment (FIG. 19) is formed in a through hole 15A that does not have a minimum portion 15m, it can be manufactured by the method described in the first, second, or third embodiment.

[0118] <Other aspects> According to the above-mentioned Patent Document 1, high integration of the through electrode substrate is realized, but there are cases where the through electrode is required to have a higher strength in the portion connecting the wiring portion and the through electrode.

[0119] Another aspect of the present disclosure is to increase the strength of the through electrodes in the through electrode substrate.

[0120] According to another aspect of the present disclosure, there is provided a through-hole electrode substrate including a substrate having a first surface and a second surface and including a through-hole penetrating the first surface and the second surface, and a through-hole electrode disposed inside the through-hole. The through-hole electrode includes a first portion closing the through-hole on the first surface side and a second portion disposed along an inner surface of the through-hole. A thinnest portion along a direction perpendicular to the first surface in the first portion has a thickness A, a thinnest portion in the second portion has a thickness B, a diameter of the through-hole on the first surface has a length C, and a relationship of A < C < A + B×2 is satisfied.

[0121] The first portion may include a portion where the thickness of the first portion becomes thicker as it moves away from the central axis of the through-hole.

[0122] According to another aspect of the present disclosure, there is provided a through-hole electrode substrate including a substrate having a first surface and a second surface and including a through-hole penetrating the first surface and the second surface, and a through-hole electrode disposed inside the through-hole. The through-hole electrode includes a first portion closing the through-hole on the first surface side and a second portion disposed along an inner surface of the through-hole. There is provided a through-hole electrode substrate, wherein the first portion includes a portion where the thickness of the first portion along a direction perpendicular to the first surface becomes thicker as it moves away from the central axis of the through-hole.

[0123] When viewed in a cross-section including the central axis of the through-hole, a surface of the first portion located inside the through-hole may have a maximum curvature at the thinnest portion of the first portion.

[0124] The thinnest portion in the first portion may be located at a position corresponding to the central axis of the through-hole.

[0125] The through hole has a minimum portion where the diameter of the through hole is at a minimum value, the minimum portion being located between the first surface and the second surface, and the through electrode may not block the through hole at the minimum portion.

[0126] The substrate may further include a wiring layer arranged on the first surface side and in contact with the through electrode, and when viewed along a direction perpendicular to the first surface, the contact area where the wiring layer and the through electrode are in contact may overlap with the through hole.

[0127] When viewed along a direction perpendicular to the first surface, the contact region may be surrounded by an outer edge of the through hole in the first surface.

[0128] When viewed along a direction perpendicular to the first surface, the contact region may overlap an outer edge of the through hole in the first surface.

[0129] The contact area may include multiple areas.

[0130] The surface of the first portion on the first surface side may be located inside the through hole.

[0131] The through hole may further include a filler located in a portion other than the metal layer of the through electrode.

[0132] The filler may include a material having electrical conductivity.

[0133] The substrate may further include a second wiring layer arranged on the second surface side and in contact with the filler, and when viewed along a direction perpendicular to the second surface, the contact area where the second wiring layer and the filler are in contact may be surrounded by the outer edge of the through hole on the second surface.

[0134] The filler may include an insulating material.

[0135] When viewed in a cross section including the central axis of the through hole, the surface of the first portion located inside the through hole may have a radius of curvature ra at the thinnest part of the first portion, and the radius of the through hole at the first surface may have a length rb, and the relationship ra / rb≧0.2 may be satisfied.

[0136] According to another aspect of the present disclosure, there is provided an electronic unit including the through electrode substrate described above and an electronic device electrically connected to the through electrode of the through electrode substrate.

[0137] The electronic device may include an electrode electrically connected to the through electrode, and the electrode of the electronic device may overlap the through electrode when viewed along a direction perpendicular to the first surface of the through electrode substrate.

[0138] According to another aspect of the present disclosure, there is provided a method for manufacturing a through electrode substrate, the method including: forming a seed layer along the inner surface of the through hole on a substrate having a first surface and a second surface and including a through hole penetrating the first surface and the second surface; forming an electrolytic plating layer on the seed layer under first electrolytic plating conditions to a thickness that does not block the through hole; and further forming the electrolytic plating layer under second electrolytic plating conditions in which the formation rate is faster on the first surface side than on the second surface side to block the first surface side of the through hole.

[0139] A fluid may be introduced into the through hole from the second surface side and solidified to form a filler that fills the inside of the through hole in the area other than the electroplated layer.

[0140] According to another aspect of the present disclosure, there is provided a method for manufacturing the electronic unit described above, which may include a step of electrically connecting the through electrode and the electrode by heating the electronic device while applying pressure toward the through electrode substrate to the electronic device.

[0141] According to another aspect of the present disclosure, the strength of the through electrodes in the through electrode substrate can be increased. [Explanation of symbols]

[0142] 10...through electrode substrate, 11...glass substrate, 15, 15A, 15E...through hole, 15m...minimum portion, 16...first end, 17...second end, 18, 18A, 18E...space, 50...wiring structure portion, 70, 70C...wiring laminate, 80, 80C...wiring substrate, 91...printed wiring board, 92, 93...electronic device, 100, 100A, 100C, 100D, 100E...through electrode, 100a...first metal layer, 100b...second metal layer, 100c...third metal layer, 102, 102A...pad portion, 103, 10 3A...through portion, 105, 105A...blocking portion, 109, 109C, 109D...filler, 110, 810, 910...first surface, 120, 820, 920...second surface, 150E...bottomed hole, 180, 180A, 180E...opening, 500...smartphone, 600...notebook personal computer, 710...interlayer insulating layer, 720, 720C...wiring layer, 811, 911, 921, 922, 923...electrodes, 891, 892, 893...bump, 1000...electronic unit, 1100...control unit

Claims

1. a substrate having a first surface and a second surface and including a through hole penetrating the first surface and the second surface; a through electrode disposed inside the through hole, a wiring stack located on the first surface, the through electrode includes a first portion that closes the through hole on the first surface side, and a second portion that is disposed along an inner side surface of the through hole, the wiring stack includes an interlayer insulating layer having an opening formed therein and a portion located in the opening; a wiring layer connected to the first portion of the through electrode, The first portion includes a surface (Bs) located on an inner side of the through hole, The surface (Bs) of the first portion has an arched structure including a portion that moves toward the second surface as it moves away from the center of the through hole when the through hole is viewed perpendicular to the first surface, the first portion includes a surface (Ts) located on the same surface as the first surface on the first surface side, The interlayer insulating layer includes a portion that overlaps both the surface (Ts) of the first portion and the first surface of the substrate when viewed perpendicularly to the first surface.

2. The through hole electrode substrate according to claim 1 , wherein the opening in the interlayer insulating layer extends in a direction perpendicular to the first surface.

3. 3. The through electrode substrate according to claim 1, wherein a contact region, which is a region where the portion of the wiring layer located in the opening of the interlayer insulating layer contacts the first portion of the through electrode, is surrounded by an outer edge of the through hole on the first surface when viewed along a direction perpendicular to the first surface.

4. 3. The through electrode substrate according to claim 1, wherein a contact region, which is a region where the portion of the wiring layer located in the opening of the interlayer insulating layer contacts the first portion of the through electrode, overlaps with the through hole when viewed along a direction perpendicular to the first surface, but is not surrounded by an outer edge of the through hole on the first surface.

5. The through electrode substrate according to any one of claims 1 to 4, wherein the wiring layer includes wiring extending in an in-plane direction of the first surface, and a connection layer located in the opening of the interlayer insulating layer and connecting the wiring to the first portion of the through electrode.

6. a plurality of the openings are formed in the interlayer insulating layer; The through electrode substrate according to claim 5 , wherein the wiring layer includes a plurality of connection layers located in the plurality of openings, respectively, and connecting the wiring to the first portion of the through electrode.

7. The through-hole electrode substrate according to claim 1 , wherein the interlayer insulating layer contains an organic material.

8. The through hole electrode substrate according to claim 1 , wherein the interlayer insulating layer contains an inorganic material.

9. the second portion extends along the inner side surface of the through hole to the second surface side of the through hole, The through hole electrode substrate according to claim 1 , wherein the second portion is arranged so as not to block an area inside the through hole other than the first portion.

10. The through electrode substrate according to claim 9 , wherein an insulator is filled in a space surrounded by the through electrode inside the through hole.

11. The through hole has a minimum portion where the diameter of the through hole is a minimum value, The through hole electrode substrate according to claim 1 , wherein the minimum portion is located between the first surface and the second surface.

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