Capacitor

Abstract

This capacitor comprises: a substrate 2 which has a first main surface on one side and a second main surface on the other side; a plurality of through holes 3 for first inner electrode formation, said through holes penetrating the substrate in the thickness direction; a plurality of through holes 4 for second inner electrode formation, said through holes penetrating the substrate in the thickness direction; a first inner electrode 5 which is formed of a conductor that is embedded in a through hole for first inner electrode formation; and a second inner electrode 6 which is formed of a conductor that is embedded in a through hole for second inner electrode formation. A plurality of through holes 3, 4 for inner electrode formation including a plurality of through holes 3 for first inner electrode formation and a plurality of through holes 4 for second inner electrode formation are arranged in a grid pattern when viewed in plan from the normal direction that is perpendicular to the first main surface.

Description

Technical Field

[0001] This invention relates to a capacitor To .

Background Art

[0002] Figures 1 and 2 of Patent Document 1 disclose a capacitor element having a first embedded electrode embedded in a first opening formed in one surface (upper surface) of a substrate and a second embedded electrode embedded in a second opening formed in the other surface (lower surface) of the substrate. The substrate is composed of a silicon substrate and a silicon oxide layer (BOX layer) laminated on the silicon substrate. The first opening is a recess of an upward opening that does not penetrate the substrate. Further, the second opening is a recess of a downward opening that does not penetrate the substrate.

[0003] As shown in Figure 2 of Patent Document 1, the first embedded electrode and the second embedded electrode are arranged in a comb shape in which the two enter each other in a plan view. In addition, Patent Document 1 discloses that, as shown in Figure 3 of Patent Document 1, the first embedded electrode and the second embedded electrode may be composed of a circular first embedded electrode arranged in the central portion and an annular second embedded electrode and an annular first electrode alternately arranged concentrically with the circular first embedded electrode in a plan view.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] An object of this invention is to provide a capacitor having a novel configuration.

Means for Solving the Problems

[0007] One embodiment of the present invention provides a capacitor including a substrate having a first main surface on one side and a second main surface on the other side, a plurality of through-holes for forming first internal electrodes penetrating the substrate in the thickness direction, a plurality of through-holes for forming second internal electrodes penetrating the substrate in the thickness direction, a first internal electrode made of a conductor embedded in the through-holes for forming first internal electrodes, and a second internal electrode made of a conductor embedded in the through-holes for forming second internal electrodes. The plurality of through-holes for forming internal electrodes including the plurality of through-holes for forming first internal electrodes and the plurality of through-holes for forming second internal electrodes are arranged in a lattice pattern in a plan view seen from a normal direction orthogonal to the first main surface. According to this embodiment, a capacitor with a novel configuration can be obtained.

[0008] In one embodiment of the present invention, the plurality of through-holes for forming internal electrodes are arranged in a matrix pattern in the plan view.

[0009] In one embodiment of the present invention, the plurality of through-holes for forming internal electrodes are arranged in a staggered pattern in the plan view.

[0010] In one embodiment of the present invention, it includes a first external electrode disposed on the first main surface and electrically connected to the plurality of first internal electrodes, and a second external electrode disposed on the second main surface and electrically connected to the plurality of second internal electrodes.

[0011] In one embodiment of the present invention, a first insulating film is formed on the first main surface so as to cover the end portion of the second internal electrode on the first main surface side, and has a first contact hole for exposing the end portion of the first internal electrode on the first main surface side; and a second insulating film is formed on the second main surface so as to cover the end portion of the first internal electrode on the second main surface side, and has a second contact hole for exposing the end portion of the second internal electrode on the second main surface side. The first external electrode is formed on the first main surface so as to cover at least a part of the exposed surface of the first insulating film and the end portion of the plurality of first internal electrodes on the first main surface side. The second external electrode is formed on the second main surface so as to cover at least a part of the exposed surface of the second insulating film and the end portion of the plurality of second internal electrodes on the second main surface side. The first external electrode enters the first contact hole and is connected to the first internal electrode within the first contact hole. The second external electrode enters the second contact hole and is connected to the second internal electrode within the second contact hole.

[0012] In one embodiment of the present invention, the aspect ratios of the through-holes for forming the first internal electrode and the through-holes for forming the second internal electrode are 50 or more.

[0013] In one embodiment of the present invention, the depths of the through-holes for forming the first internal electrode and the through-holes for forming the second internal electrode are 100 μm or more.

[0014] In one embodiment of the present invention, the maximum width or maximum diameter of the cross-section of the through-holes for forming the first internal electrode and the through-holes for forming the second internal electrode is 0.3 μm or more and 10 μm or less.

[0015] In one embodiment of the present invention, the inter-electrode distance of the plurality of internal electrodes including the first internal electrode and the second internal electrode is 0.3 μm or more and 10 μm or less.

[0016] In one embodiment of the present invention, the conductor is composed of one arbitrarily selected from Cu, Al, Pt, Au, Ag, Ni, and polysilicon.

[0017] One embodiment of the present invention provides a capacitor including: a substrate having a first main surface on one side and a second main surface on the other side; a plurality of through-holes for forming first internal electrodes penetrating the substrate in the thickness direction; a plurality of through-holes for forming second internal electrodes penetrating the substrate in the thickness direction; a first internal electrode made of a conductor embedded in the through-holes for forming first internal electrodes; a second internal electrode made of a conductor embedded in the through-holes for forming second internal electrodes; a first insulating film formed on the first main surface so as to cover the end portion of the second internal electrode on the first main surface side and having a first contact hole for exposing the end portion of the first internal electrode on the first main surface side; a second insulating film formed on the second main surface so as to cover the end portion of the first internal electrode on the second main surface side and having a second contact hole for exposing the end portion of the second internal electrode on the second main surface side; a first external electrode formed on the first main surface so as to cover at least a part of the exposed surface of the first insulating film and the end portions of the plurality of first internal electrodes on the first main surface side, and the plurality of first internal electrodes being electrically connected; and a second external electrode formed on the second main surface so as to cover at least a part of the exposed surface of the second insulating film and the end portions of the plurality of second internal electrodes on the second main surface side, and the plurality of second internal electrodes being electrically connected. According to this embodiment, a capacitor with a novel structure can be obtained.

[0018] In one embodiment of the present invention, the first external electrode enters the first contact hole and is connected to the first internal electrode within the first contact hole, and the second external electrode enters the second contact hole and is connected to the second internal electrode within the second contact hole.

[0019] One embodiment of the present invention provides a method for manufacturing a capacitor, which includes: a first step of forming, on a substrate having a first main surface on one side and a second main surface on the other side, a plurality of through-holes for forming first internal electrodes that penetrate the substrate in the thickness direction and a plurality of through-holes for forming second internal electrodes that penetrate the substrate in the thickness direction; and a second step of forming a first internal electrode in the through-holes for forming first internal electrodes and a second internal electrode in the through-holes for forming second internal electrodes by embedding a conductor in the through-holes for forming first internal electrodes and the through-holes for forming second internal electrodes. According to this embodiment, a novel method for manufacturing a capacitor can be provided.

[0020] In one embodiment of the present invention, the method further includes: a third step of forming a first insulating layer on the first main surface so as to cover the first main surface side ends of the first internal electrode and the second internal electrode; a fourth step of forming a first contact hole for exposing the first main surface side end of the first internal electrode in the first insulating layer; a fifth step of forming a second insulating layer on the second main surface so as to cover the second main surface side ends of the first internal electrode and the second internal electrode; a sixth step of forming a second contact hole for exposing the second main surface side end of the second internal electrode in the second insulating layer; and a seventh step of forming a first external electrode connected to the first internal electrode through the first contact hole on the first insulating film and forming a second external electrode connected to the second internal electrode through the second contact hole on the second insulating film.

[0021] In one embodiment of the present invention, in the first step, the plurality of through-holes for forming internal electrodes, which include the plurality of through-holes for forming first internal electrodes and the plurality of through-holes for forming second internal electrodes, are formed in the substrate so as to be arranged in a grid pattern in a plan view seen from a normal direction perpendicular to the first main surface.

[0022] In one embodiment of the present invention, the plurality of through-holes for forming internal electrodes are formed in the substrate so as to be arranged in a matrix pattern in the plan view.

[0023] In one embodiment of the present invention, the plurality of through-holes for forming internal electrodes are formed in the substrate so as to be arranged in a staggered pattern in the plan view.

[0024] The above-mentioned, or further other objects, features, and effects of the present invention will be clarified by the description of the embodiments described below with reference to the accompanying drawings.

Brief Description of the Drawings

[0025]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5A

Figure 5B

Figure 5C

Figure 5D

Figure 5E

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

DETAILED DESCRIPTION OF THE INVENTION

[0026] FIG. 1 is a schematic plan view of a capacitor according to the first embodiment of the present invention. FIG. 2 is a schematic cross-sectional view taken along line II-II of FIG. 1. FIG. 3 is a schematic cross-sectional view taken along line III-III of FIG. 2. FIG. 4 is a schematic cross-sectional view taken along line IV-IV of FIG. 2.

[0027] However, in FIG. 1, the first insulating film 7 and the first external electrode 8 in FIG. 2 are omitted. Further, in FIG. 1, in order to easily distinguish the first internal electrode 5 from the second internal electrode 6, the first internal electrode 5 is shown by dot hatching, and the second internal electrode 6 is shown by cross hatching.

[0028] Hereinafter, the vertical direction in FIG. 1 is referred to as the longitudinal direction, and the horizontal direction in FIG. 1 is referred to as the lateral direction.

[0029] Referring to FIGS. 1 and 2, the capacitor 1 has a rectangular parallelepiped shape. The capacitor 1 includes a substrate 2.

[0030] The substrate 2 has a rectangular parallelepiped shape and includes a pair of main surfaces 2a and 2b and four side surfaces 2c. Of the pair of main surfaces 2a and 2b, the main surface 2a on the upper surface side in FIG. 2 is referred to as the "first main surface 2a", and the main surface 2b on the side opposite to the first main surface 2a is referred to as the "second main surface 2b". In a plan view seen from the normal direction orthogonal to the first main surface 2a, the substrate 2 has a square shape, and the length of one side thereof is, for example, about 5 mm. The plan view shape of the substrate 2 may be a shape other than a square shape, such as a rectangular shape or a circular shape. Further, the thickness of the substrate 2 is, for example, 100 μm or more, and in this embodiment, it is about 400 μm, for example. In this embodiment, the substrate 2 is made of silicon oxide (SiO2) formed by thermal oxidation of a silicon substrate. Note that the substrate 2 may be a silicon substrate.

[0031] A plurality of through-holes 3 for forming the first internal electrodes penetrating the substrate 2 in the thickness direction and a plurality of through-holes 4 for forming the second internal electrodes penetrating the substrate 2 in the thickness direction are formed in the substrate 2. The plurality of through-holes 3, 4 for forming the internal electrodes including the plurality of through-holes 3 for forming the first internal electrodes and the plurality of through-holes 4 for forming the second internal electrodes are arranged in a lattice shape in a plan view. In this embodiment, the plurality of through-holes 3, 4 for forming the internal electrodes are arranged in a matrix shape in a plan view. In this embodiment, the plurality of through-holes 3, 4 for forming the internal electrodes are arranged side by side at equal intervals in the longitudinal direction and the lateral direction in a plan view.

[0032] In this embodiment, the cross-sectional shape of each through-hole 3, 4 for forming an internal electrode is square, and the length of one side thereof is, for example, about 0.3 μm or more and 10 μm or less. In this embodiment, the length of one side is, for example, about 5 μm. The depth of each through-hole 3, 4 for forming an internal electrode is the same as the thickness of the substrate 2. The first through-hole 3 for forming an internal electrode and the second through-hole 4 for forming an internal electrode are arranged alternately in the vertical and horizontal directions respectively.

[0033] In each first through-hole 3 for forming an internal electrode, a first internal electrode 5 made of a conductor is embedded. In each second through-hole 4 for forming an internal electrode, a second internal electrode 6 made of a conductor is embedded. The electrode distance between a plurality of internal electrodes 5, 6 including the first internal electrode 5 and the second internal electrode 6 is about 0.3 μm or more and 10 μm or less.

[0034] The first internal electrode 5 is composed of a seed layer 5A formed on the inner surface of the first through-hole 3 for forming an internal electrode and an internal electrode layer 5B embedded in the first through-hole 3 for forming an internal electrode while being surrounded by the seed layer 5A. In this embodiment, the seed layer 5A and the internal electrode layer 5B are made of copper (Cu). The seed layer 5A and the internal electrode layer 5B may be composed of a metal such as Al, Pt, Au, Ag, Ni or polysilicon.

[0035] The second internal electrode 6 is composed of a seed layer 6A formed on the inner surface of the second through-hole 4 for forming an internal electrode and an internal electrode layer 6B embedded in the second through-hole 4 for forming an internal electrode while being surrounded by the seed layer 6A. In this embodiment, the seed layer 6A and the internal electrode layer 6B are made of copper (Cu). The seed layer 6A and the internal electrode layer 6B may be composed of a metal such as Al, Pt, Au, Ag, Ni or polysilicon.

[0036] Referring to FIGS. 2 and 3, on the first main surface 2a of the substrate 2, a first insulating film 7 is formed so as to cover the first main surface 2a and the second internal electrode 6. In the first insulating film 7, a first contact hole 7a is formed to expose the end portion of the first internal electrode 5 on the first main surface side. The first insulating film 7 is made of, for example, a SiO2 film. The first insulating film 7 may be composed of a SiN film, a SiON film, or the like. In this embodiment, the planar shape of the first contact hole 7a is a square shape having a size substantially equal to the size of the cross section of the first internal electrode 5. The planar shape of the first contact hole 7a may be a shape other than a square shape, such as a rectangular shape or a circular shape.

[0037] On the first main surface 2a of the substrate 2, a first external electrode 8 is formed so as to cover at least a part of the exposed surface of the first insulating film 7 and the end portions of all the first internal electrodes 5 on the first main surface side. The first external electrode 8 enters the first contact hole 7a of the first insulating film 7 and is connected to the end portion of the first internal electrode 5 on the first main surface side within the first contact hole 7a. Thereby, the first external electrode 8 is electrically connected to the first internal electrode 5. In this embodiment, among the exposed surfaces of the first insulating film 7, the exposed surfaces other than the outer surface of the first insulating film 7 are covered by the first external electrode 8.

[0038] The first external electrode 8 includes a seed layer 8A formed so as to cover the exposed surface (excluding the outer surface) of the first insulating film 7 and the exposed surfaces of the end portions of all the first internal electrodes 5 on the first main surface side, and an external electrode layer 8B laminated on the seed layer 8A. In this embodiment, the seed layer 8A and the external electrode layer 8B are made of copper (Cu). The seed layer 8A may be composed of, in addition to Cu, Al, Pt, Au, Ag, Ni, or the like. The external electrode layer 8B may be composed of, in addition to Cu, Al, Pt, Au, Ag, Ni, or the like.

[0039] Referring to FIGS. 2 and 4, a second insulating film 9 is formed on the second main surface 2b of the substrate 2 so as to cover the second main surface 2B and the first internal electrode 5. A second contact hole 9a for exposing the end portion on the second main surface side of the second internal electrode 6 is formed in the second insulating film 9. The second insulating film 9 is made of, for example, a SiO2 film. The second insulating film 9 may be composed of a SiN film, a SiON film, or the like. In this embodiment, the planar shape of the second contact hole 9a is a square shape having a size substantially equal to the size of the cross section of the second internal electrode 6. The planar shape of the second contact hole 9a may be a shape other than a square shape, such as a rectangular shape or a circular shape.

[0040] A second external electrode 10 is formed on the second main surface 2b of the substrate 2 so as to cover at least a part of the exposed surface of the second insulating film 9 and the end portions on the second main surface side of all the second internal electrodes 6. The second external electrode 10 enters the second contact hole 9a of the second insulating film 9 and is connected to the end portion on the second main surface side of the second internal electrode 6 within the second contact hole 9a. Thereby, the second external electrode 10 is electrically connected to the second internal electrode 6. In this embodiment, among the exposed surfaces of the second insulating film 9, the exposed surfaces other than the outer surface of the second insulating film 9 are covered by the second external electrode 10.

[0041] The second external electrode 10 includes a seed layer 10A formed so as to cover the exposed surface (excluding the outer surface) of the second insulating film 9 and the exposed surfaces of the end portions on the second main surface side of all the second internal electrodes 6, and an external electrode layer 10B laminated on the seed layer 10A. In this embodiment, the seed layer 10A and the external electrode layer 10B are made of copper (Cu). The seed layer 10A may be composed of, in addition to Cu, Al, Pt, Au, Ag, Ni, or the like. The external electrode layer 10B may be composed of, in addition to Cu, Al, Pt, Au, Ag, Ni, or the like.

[0042] In the configuration as described above, the first internal electrode 5 and the second internal electrode 6 adjacent to each other in the vertical direction have opposing surfaces that face each other in the vertical direction. And the wall of the substrate 2 sandwiched between the opposing surfaces of the first internal electrode 5 and the second internal electrode 6 adjacent to each other in the vertical direction constitutes a capacitance film (dielectric film). One capacitor element is constituted by a set of the first internal electrode 5 and the second internal electrode 6 adjacent to each other in the vertical direction and the capacitance film therebetween.

[0043] Similarly, the first internal electrode 5 and the second internal electrode 6 adjacent to each other in the horizontal direction have opposing surfaces that face each other in the horizontal direction. And the wall of the substrate 2 sandwiched between the opposing surfaces of the first internal electrode 5 and the second internal electrode 6 adjacent to each other in the horizontal direction constitutes a capacitance film (dielectric film). One capacitor element is constituted by a set of the first internal electrode 5 and the second internal electrode 6 adjacent to each other in the horizontal direction and the capacitance film therebetween.

[0044] And since the plurality of first internal electrodes 5 are electrically connected to the first external electrode 8 and the plurality of second internal electrodes 6 are electrically connected to the second external electrode 10, a configuration in which all the capacitor elements are connected in parallel can be obtained. Thereby, a capacitor that can be miniaturized and increased in capacitance can be provided.

[0045] Also, since the through holes 3 for forming the first internal electrode and the through holes 4 for forming the second internal electrode are formed in the substrate 2, and the first internal electrode 5 and the second internal electrode 6 can be formed by embedding a conductor in these through holes 3 and 4 for forming internal electrodes, the manufacturing of the first internal electrode 5 and the second internal electrode 6 is easy. Thereby, a capacitor that is easy to manufacture can be provided.

[0046] Figs. 5A to 5E are cross-sectional views for explaining an example of the manufacturing process of the capacitor, and show a cross-section corresponding to Fig. 2.

[0047] First, as shown in FIG. 5A, a base substrate 40 that serves as the base of the substrate 2 is prepared. The base substrate 40 has a first main surface 40a, a second main surface 40b on the side opposite to the first main surface 40a, and four side surfaces 40c that connect the first main surface 40a and the second main surface 40b. The base substrate 40 is a silicon substrate. Through holes 3 for forming the first internal electrode and 4 for forming the second internal electrode are formed in the base substrate 40, for example, by an electrochemical etching method. These through holes 3 and 4 for forming the internal electrodes may be formed by laser processing.

[0048] Next, as shown in FIG. 5B, the entire base substrate 40 is oxidized by thermal oxidation. As a result, the base substrate 40 becomes a substrate 2 made of SiO2. The first main surface 40a of the base substrate 40 becomes the first main surface 2a of the substrate 2, the second main surface 40b of the base substrate 40 becomes the second main surface 2b of the substrate 2, and the side surface 40c of the base substrate 40 becomes the side surface 2c of the substrate 2.

[0049] Next, as shown in FIG. 5C, a seed layer 5A is formed on the inner surface of the through hole 3 for forming the first internal electrode, and at the same time, a seed layer 6A is formed on the inner surface of the through hole 4 for forming the second internal electrode. The seed layers 5A and 6A are, for example, Cu seed layers. The seed layers 5A and 6A are formed, for example, by an atomic layer deposition (ALD) method.

[0050] Next, as shown in FIG. 5D, for example, by an electroplating method, an internal electrode layer 5B is formed on the seed layer 5A in the through hole 3 for forming the first internal electrode, and at the same time, an internal electrode layer 6B is formed on the seed layer 6A in the through hole 4 for forming the second internal electrode. The internal electrode layer 5B and the internal electrode layer 6B are made of, for example, Cu. As a result, a state is achieved in which a first internal electrode 5 composed of the seed layer 5A and the internal electrode layer 5B is embedded in the through hole 3 for forming the first internal electrode. Also, a state is achieved in which a second internal electrode 6 composed of the seed layer 6A and the internal electrode layer 6B is embedded in the through hole 4 for forming the second internal electrode.

[0051] Next, as shown in FIG. 5E, on the first main surface 2a of the substrate 2, for example, by sputtering, a first insulating film 7 is formed so as to cover the first main surface 2a, the first main surface side end portions of the first internal electrodes 5, and the first main surface side end portions of the second internal electrodes 6. The first insulating film 7 may be formed by chemical vapor deposition (CVD). The first insulating film 7 is made of, for example, a SiO2 film. Then, by photolithography and etching, a first contact hole 7a for exposing the first main surface side end portion of the first internal electrode 5 is formed in the first insulating film 7.

[0052] Thereafter, on the second main surface 2b of the substrate 2, for example, by sputtering, a second insulating film 9 is formed so as to cover the second main surface 2b, the second main surface side end portions of the first internal electrodes 5, and the second main surface side end portions of the second internal electrodes 6. The second insulating film 9 may be formed by CVD. The second insulating film 9 is made of, for example, a SiO2 film. Then, by photolithography and etching, a second contact hole 9a for exposing the second main surface side end portion of the second internal electrode 6 is formed in the second insulating film 9.

[0053] Finally, a first external electrode 8 is formed on the first main surface 2a of the substrate 2, and a second external electrode 10 is formed on the second main surface 2b of the substrate 2, whereby the capacitor 1 shown in FIGS. 1 and 2 is obtained.

[0054] The first external electrode 8 is formed, for example, as follows. First, for example, by sputtering, a seed layer 8A is formed so as to cover the exposed surface (excluding the outer surface) of the first insulating film 7 and the exposed surfaces of the first main surface side end portions of all the first internal electrodes 5. Then, for example, by plating, an external electrode layer 8B is formed on the seed layer 8A. Thereby, the first external electrode 8, which is composed of the seed layer 8A and the external electrode layer 8B and is electrically connected to all the first internal electrodes 5, is formed on the first main surface 2a.

[0055] The second external electrode 10 is formed, for example, as follows. First, a seed layer 10A is formed, for example, by sputtering, so as to cover the exposed surface (excluding the outer surface) of the second insulating film 9 and the exposed surfaces of the second main surface side ends of all the second internal electrodes 6. Then, an external electrode layer 10B is formed on the seed layer 10A, for example, by plating. Thereby, the second external electrode 10, which is composed of the seed layer 10A and the external electrode layer 10B and is electrically connected to all the second internal electrodes 6, is formed on the second main surface 2b.

[0056] Figs. 6 to 13 are plan views showing modified examples in which one or both of the cross-sectional shapes and arrangements of the first internal electrode forming through-holes 3 and the second internal electrode forming through-holes 4 are different, and are plan views corresponding to Fig. 1. In Figs. 6 to 13, the same reference numerals as those in Fig. 1 are given to the corresponding parts in Fig. 1.

[0057] As shown in Fig. 6, the cross-sectional shapes of the first internal electrode forming through-hole 3 and the second internal electrode forming through-hole 4 may be circular. In this case, the cross-sectional shapes of the first internal electrode 5 embedded in the first internal electrode forming through-hole 3 and the second internal electrode 6 embedded in the second internal electrode forming through-hole 4 also become circular.

[0058] Also, as shown in Fig. 7, the cross-sectional shapes of the first internal electrode forming through-hole 3 and the second internal electrode forming through-hole 4 may be regular hexagonal. In this case, the cross-sectional shapes of the first internal electrode 5 embedded in the first internal electrode forming through-hole 3 and the second internal electrode 6 embedded in the second internal electrode forming through-hole 4 also become regular hexagonal.

[0059] Also, as shown in Figs. 8 to 12, the plurality of internal electrode forming through-holes 3, 4 including the plurality of first internal electrode forming through-holes 3 and the plurality of second internal electrode forming through-holes 4 may be arranged in a staggered pattern in a plan view.

[0060] In the example of FIG. 8, the cross-sectional shape of each through-hole 3, 4 for forming an internal electrode is a square shape, similar to FIG. 1. In the example of FIG. 8, the first through-hole 3 for forming an internal electrode and the second through-hole 4 for forming an internal electrode are arranged alternately only in the horizontal direction. In the example of FIG. 9, the cross-sectional shape of each through-hole 3, 4 for forming an internal electrode is a circular shape.

[0061] In the examples of FIGS. 10 to 12, the cross-sectional shape of each through-hole 3, 4 for forming an internal electrode is a regular hexagonal shape. In FIGS. 10 to 12, the horizontal arrangement of the through-holes 3, 4 for forming an internal electrode is referred to as a row, and the vertical arrangement of the through-holes 3, 4 for forming an internal electrode is referred to as a column. Each row is referred to as the first row, the second row, the third row,..., the Nth row from the lower side to the upper side of the figure.

[0062] In the examples of FIGS. 10 and 11, the left end of the even rows is shifted to the left with respect to the left end of the odd rows. In FIGS. 10 and 11, in each row, the first through-hole 3 for forming an internal electrode and the second through-hole 4 for forming an internal electrode are alternately arranged in the horizontal direction. However, in FIG. 10, in each row, the first through-hole 3 for forming an internal electrode is arranged at the left end.

[0063] On the other hand, in FIG. 11, at the left end of the odd rows, the first through-hole 3 for forming an internal electrode and the second through-hole 4 for forming an internal electrode are alternately arranged in the vertical direction, and at the left end of the even rows, the first through-hole 3 for forming an internal electrode and the second through-hole 4 for forming an internal electrode are alternately arranged in the vertical direction.

[0064] In the example of FIG. 12, the third through-hole for forming an internal electrode from the left in the sixth row is the second through-hole 4 for forming an internal electrode. Taking this second through-hole 4 for forming an internal electrode as the basic through-hole 4 (shown as 4(P) in FIG. 12), the first through-hole 3 for forming an internal electrode and the second through-hole 4 for forming an internal electrode are alternately arranged in a substantially annular or substantially arc shape centered on the basic through-hole 4.

[0065] FIG. 13 shows that although the cross-sectional shapes of the through-holes 3 and 4 for forming the internal electrodes are circular, the overall arrangement of them in a plan view is the same matrix pattern as that in FIG. 1. However, the arrangement of the first through-hole 3 for forming the internal electrode and the second through-hole 4 for forming the internal electrode is different from that in FIG. 1. In FIG. 13, the horizontal arrangement of the through-holes 3 and 4 for forming the internal electrodes is referred to as a row, the vertical arrangement of the through-holes 3 and 4 for forming the internal electrodes is referred to as a column, each column is referred to as the first column, the second column, the third column, …, the sixth column from left to right, and each row is referred to as the first row, the second row, the third row, …, the sixth row from bottom to top.

[0066] The first column and the fourth column are entirely composed of the first through-hole 3 for forming the internal electrode. The third column and the sixth column are entirely composed of the second through-hole 4 for forming the internal electrode. In the second column, the third and fifth rows are composed of the first through-hole 3 for forming the internal electrode, and the first, second, fourth, and sixth rows are composed of the second through-hole 4 for forming the internal electrode. In the fifth column, the second and fourth rows are composed of the first through-hole 3 for forming the internal electrode, and the first, third, fifth, and sixth rows are composed of the second through-hole 4 for forming the internal electrode.

[0067] FIG. 14 is a schematic plan view of a capacitor according to the second embodiment of the present invention. FIG. 15 is a schematic cross-sectional view taken along line XV-XV in FIG. 14. However, in FIG. 14, the first insulating film 7 and the main first external electrode 81 in FIG. 15 are omitted. Further, in FIG. 14, in order to easily distinguish the first internal electrode 5 and the second internal electrode 6, the first internal electrode 5 is shown by dot hatching, and the second internal electrode 6 is shown by cross hatching.

[0068] In FIG. 14, parts corresponding to those in FIG. 1 are denoted by the same reference numerals as in FIG. 1. In FIG. 15, parts corresponding to those in FIG. 2 are denoted by the same reference numerals as in FIG. 2.

[0069] Hereinafter, the vertical direction in FIG. 14 is referred to as the longitudinal direction, and the horizontal direction in FIG. 14 is referred to as the lateral direction.

[0070] The capacitor 1A has a rectangular parallelepiped shape. The capacitor 1A includes a substrate 2.

[0071] The substrate 2 is in the shape of a rectangular parallelepiped and includes a pair of main surfaces 2a and 2b and four side surfaces 2c. Of the pair of main surfaces 2a and 2b, the main surface 2a on the upper surface side in FIG. 15 is referred to as the "first main surface 2a", and the main surface 2b on the side opposite to the first main surface 2a is referred to as the "second main surface 2b". In a plan view seen from the normal direction orthogonal to the first main surface 2a, the substrate 2 is rectangular, the length of its long side is, for example, about 10 mm, and the length of its short side is, for example, about 5 mm. Also, the thickness of the substrate 2 is, for example, 100 μm or more, and in this embodiment, it is about 400 μm, for example. In this embodiment, the substrate 2 is made of silicon oxide (SiO2) formed by thermally oxidizing a silicon substrate. Note that the substrate 2 may be a silicon substrate.

[0072] A plurality of through-holes 3 for forming first internal electrodes, a plurality of through-holes 4 for forming second internal electrodes, and a plurality of through-holes 21 for connecting external electrodes, which penetrate the substrate 2 in the thickness direction, are formed in the substrate 2. The plurality of through-holes 3 and 4 for forming internal electrodes, including the plurality of through-holes 3 for forming first internal electrodes and the plurality of through-holes 4 for forming second internal electrodes, are arranged in a matrix in a plan view. In this embodiment, the plurality of through-holes 3 and 4 for forming internal electrodes are arranged at equal intervals in the vertical and horizontal directions in a plan view.

[0073] The plurality of through-holes 21 for connecting external electrodes are arranged side by side in the vertical direction on one side (the left side in FIG. 14 in this example) of the plurality of through-holes 3 and 4 for forming internal electrodes arranged in a matrix in a plan view. In this embodiment, the plurality of through-holes 3, 4, and 21, including the plurality of through-holes 3 for forming first internal electrodes, the plurality of through-holes 4 for forming second internal electrodes, and the plurality of through-holes 21 for connecting external electrodes, are also arranged in a matrix. In this embodiment, the plurality of through-holes 3, 4, and 21 are arranged at equal intervals in the vertical and horizontal directions in a plan view.

[0074] In this embodiment, the cross-sectional shape of each of the through-holes 3, 4, and 21 is square, and the length of one side thereof is, for example, about 0.3 μm or more and 10 μm or less. In this embodiment, the length of the one side is, for example, about 5 μm.

[0075] The through-hole 3 for forming the first internal electrode and the through-hole 4 for forming the second internal electrode are alternately arranged side by side in the vertical and horizontal directions, respectively.

[0076] On the second main surface 2b of the substrate 2, in a plan view, a region on the right side of the virtual straight line L1 in the vertical direction passing through the left ends of the through-holes 3 and 4 for forming the internal electrodes is defined as the first region S1. Also, on the second main surface 2b of the substrate 2, in a plan view, a region on the left side of the virtual straight line L2 in the vertical direction passing through the right end of the through-hole 21 for connecting the external electrode is defined as the second region S2.

[0077] In each through-hole 3 for forming the first internal electrode, a first internal electrode 5 made of a conductor is embedded. In each through-hole 4 for forming the second internal electrode, a second internal electrode 6 made of a conductor is embedded. In the through-hole 21 for connecting the external electrode, an external electrode connection member 22 made of a conductor is embedded. The electrode pitch between the plurality of internal electrodes 5 and 6 including the first internal electrode 5 and the second internal electrode 6 is about 0.3 μm or more and 10 μm or less.

[0078] The first internal electrode 5 is composed of a seed layer 5A formed on the inner surface of the through-hole 3 for forming the first internal electrode and an internal electrode layer 5B embedded in the through-hole 3 for forming the first internal electrode while being surrounded by the seed layer 5A. In this embodiment, the seed layer 5A and the internal electrode layer 5B are made of copper (Cu). The seed layer 5A and the internal electrode layer 5B may be composed of a metal such as Al, Pt, Au, Ag, Ni or polysilicon.

[0079] The second internal electrode 6 is composed of a seed layer 6A formed on the inner surface of the through-hole 4 for forming the second internal electrode and an internal electrode layer 6B embedded in the through-hole 4 for forming the second internal electrode while being surrounded by the seed layer 6A. In this embodiment, the seed layer 6A and the internal electrode layer 6B are made of copper (Cu). The seed layer 6A and the internal electrode layer 6B may be composed of a metal such as Al, Pt, Au, Ag, Ni or polysilicon.

[0080] The external electrode connection member 22 includes a seed layer 22A formed on the inner surface of the through-hole 21 for external electrode connection, and an external electrode connection layer 22B embedded in the through-hole 21 for external electrode connection while being surrounded by the seed layer 22A. In this embodiment, the seed layer 22A and the external electrode connection layer 22B are made of copper (Cu). The seed layer 22A and the external electrode connection layer 22B may be composed of a metal such as Al, Pt, Au, Ag, Ni, or polysilicon.

[0081] On the first main surface 2a of the substrate 2, a first insulating film 7 is formed so as to cover the first main surface 2a and the second internal electrode 6. In the first insulating film 7, a first contact hole 7a for exposing the end portion of the first internal electrode 5 on the first main surface side and a third contact hole 7b for exposing the end portion of the external electrode connection member 22 on the first main surface side are formed. The first insulating film 7 is made of, for example, a SiO2 film. The first insulating film 7 may be composed of a SiN film, a SiON film, or the like. In this embodiment, the planar shapes of the first contact hole 7a and the third contact hole 7b are each a square shape having a size substantially equal to the size of the cross-section of the first internal electrode 5 and the external electrode connection member 22.

[0082] On the first main surface 2a of the substrate 2, a main first external electrode 81 is formed so as to cover at least a part of the exposed surface of the first insulating film 7 and the end portions of all the first internal electrodes 5 on the first main surface side. The main first external electrode 81 enters the first contact hole 7a of the first insulating film 7 and is connected to the end portion of the first internal electrode 5 on the first main surface side within the first contact hole 7a. Thereby, the main first external electrode 81 is electrically connected to the first internal electrode 5. In this embodiment, among the exposed surfaces of the first insulating film 7, the exposed surfaces other than the outer surface of the first insulating film 7 are covered by the main first external electrode 81.

[0083] Further, the main first external electrode 81 enters the third contact hole 7b and is connected to the end portion of the external electrode connection member 22 on the first main surface side within the third contact hole 7b. Thereby, the main first external electrode 81 is electrically connected to the external electrode connection member 22.

[0084] The main first external electrode 81 is composed of a seed layer 81A formed to cover the exposed surface (excluding the outer surface) of the first insulating film 7, the exposed surfaces of the first main surface side ends of all the first internal electrodes 5, and the first main surface side ends of all the external electrode connection members 22, and an external electrode layer 81B laminated on the seed layer 81A. In this embodiment, the seed layer 81A and the external electrode layer 81B are made of copper (Cu). The seed layer 81A may be composed of, in addition to Cu, Al, Pt, Au, Ag, Ni, etc. The external electrode layer 81B may be composed of, in addition to Cu, Al, Pt, Au, Ag, Ni, etc.

[0085] On the second main surface 2b of the substrate 2, a second insulating film 9 is formed so as to cover the second main surface 2B and the first internal electrode 5. In the second insulating film 9, a second contact hole 9a for exposing the second main surface side end of the second internal electrode 6 and a fourth contact hole 9b for exposing the second main surface side end of the external electrode connection member 22 are formed. The second insulating film 9 is made of, for example, a SiO2 film. The second insulating film 9 may be composed of a SiN film, a SiON film, etc. In this embodiment, the planar view shapes of the second contact hole 9a and the fourth contact hole 9b are each a square shape having a size substantially equal to the size of the cross section of the second internal electrode 6 and the external electrode connection member 22.

[0086] On the second main surface 2b of the substrate 2, in the first region S1, a second external electrode 10 is formed so as to cover at least a part of the exposed surface of the second insulating film 9 and the second main surface side end of the second internal electrode 6. The second external electrode 10 enters the second contact hole 9a of the second insulating film 9 and is connected to the second main surface side end of the second internal electrode 6 within the second contact hole 9a. Thereby, the second external electrode 10 is electrically connected to the second internal electrode 6. In this embodiment, in the first region S1, among the exposed surfaces of the second insulating film 9, the exposed surfaces other than the outer surface of the second insulating film 9 are covered by the second external electrode 10.

[0087] The second external electrode 10 includes a seed layer 10A formed to cover the exposed surface (excluding the outer surface) of the second insulating film 9 and the exposed surfaces of the second main surface side ends of all the second internal electrodes 6 in the first region S1, and an external electrode layer 10B laminated on the seed layer 10A. In this embodiment, the seed layer 10A and the external electrode layer 10B are made of copper (Cu). The seed layer 10A may be composed of, in addition to Cu, Al, Pt, Au, Ag, Ni, etc. The external electrode layer 10B may be composed of, in addition to Cu, Al, Pt, Au, Ag, Ni, etc.

[0088] Also, on the second main surface 2b of the substrate 2, a sub first external electrode 82 is formed in the second region S2 so as to cover at least a part of the second insulating film 9 and the second main surface side ends of all the external electrode connection members 22. The sub first external electrode 82 enters the fourth contact hole 9b of the second insulating film 9 and is connected to the second main surface side end of the external electrode connection member 22 within the fourth contact hole 9b. Thereby, the sub first external electrode 82 is electrically connected to the external electrode connection member 22. In this embodiment, in the second region S2, among the exposed surfaces of the second insulating film 9, the exposed surfaces other than the outer surface of the second insulating film 9 are covered by the sub first external electrode 82.

[0089] Thereby, the sub first external electrode 82 is electrically connected to the main first external electrode 81 via the external electrode connection member 22. That is, in this embodiment, the first external electrode 80 is constituted by the main first external electrode 81 and the sub first external electrode 82. In other words, the first external electrode 80 includes the main first external electrode 81 formed on the first main surface 2a side of the substrate 2 and the sub first external electrode 82 formed on the second main surface 2b side of the substrate 2.

[0090] The sub first external electrode 82 is composed of a seed layer 82A formed to cover the exposed surface (excluding the outer surface) of the second insulating film 9 and the exposed surface of the end portion on the second main surface side of all the external electrode connection members 22 in the second region S2, and an external electrode layer 82B laminated on the seed layer 82A. In this embodiment, the seed layer 8A and the external electrode layer 82B are made of copper (Cu). The seed layer 82A may be composed of, in addition to Cu, Al, Pt, Au, Ag, Ni, etc. The external electrode layer 82B may be composed of, in addition to Cu, Al, Pt, Au, Ag, Ni, etc.

[0091] In this embodiment, the first external electrode 80 includes a main first external electrode 81 formed on the first main surface 2a side of the substrate 2 and a sub first external electrode 82 formed on the second main surface 2b side of the substrate 2. Therefore, it is possible to connect the wiring for connecting to the first external electrode 80 to the main first external electrode 81 on the first main surface 2a side of the substrate 2, and it is also possible to connect it to the sub first external electrode 82 on the second main surface 2b side of the substrate 2. In addition, it is also possible to directly bond the second external electrode 10 and the sub first external electrode 82 to the wiring pattern on the printed circuit board.

[0092] FIG. 16 is a schematic configuration diagram of a semiconductor package in which the capacitor 1 shown in FIGS. 1 and 2 is packaged.

[0093] The semiconductor package 101 includes a flat rectangular parallelepiped resin package 102 and a first terminal 103 and a second terminal 104 sealed in the resin package 102.

[0094] The two terminals 103, 104 are made of a metal plate formed in a predetermined shape. In this embodiment, the second terminal 104 is formed in a shape including a square island 105 and an elongated rectangular terminal portion 106 extending linearly from one side of the island 105. The first terminal 103 is formed in substantially the same shape as the terminal portion 106 of the second terminal 104 and is arranged in a state parallel to the terminal portion 106 of the second terminal 104.

[0095] A capacitor 1 is die-bonded onto the second terminal 104 (the center of the island 105). The island 105 is joined from below to the second external electrode 10 of the capacitor 1.

[0096] The first terminal 103 is connected to the first external electrode 8 of the capacitor 1 using a bonding wire 107.

[0097] As described above, the first and second embodiments of the present invention have been explained. However, the present invention can be implemented in other forms. For example, the cross-sectional shapes of the first internal electrode forming through-hole 3 and the second internal electrode forming through-hole 4 are not limited to the above-described shapes and may be any shape. The cross-sectional shapes of the first internal electrode forming through-hole 3 and the second internal electrode forming through-hole 4 may be, for example, a rectangular shape that is long in one direction. In this case, the first internal electrode 5 and the second internal electrode 6 are in a flat plate shape.

[0098] In the above-described embodiment, the plurality of internal electrode forming through-holes 3, 4 including the plurality of first internal electrode forming through-holes 3 and the plurality of second internal electrode forming through-holes 4 are arranged in a lattice shape (matrix shape, staggered shape), but they do not have to be arranged in a lattice shape. For example, they may be arranged in a single row.

[0099] The embodiments of the present invention have been described in detail, but these are merely specific examples used to clarify the technical content of the present invention. The present invention should not be construed as being limited to these specific examples, and the scope of the present invention is limited only by the appended claims.

[0100] This application corresponds to Japanese Patent Application No. 2020-043084 filed with the Japan Patent Office on March 12, 2020, and the entire disclosure of that application is incorporated herein by reference.

Explanation of Reference Numerals

[0101] 1, 1A Capacitor 2 Substrate 2a First main surface 2b Second main surface 3 Through-hole for forming the first internal electrode 4 Through-hole for forming the second internal electrode 5 First internal electrode 5A Seed layer 5B Internal electrode layer 6 Second internal electrode 6A Seed layer 6B Internal electrode layer 7 First insulating film 7a First contact hole 7b Third contact hole 8 First external electrode 8A Seed layer 8B External electrode layer 9 Second insulating film 9a Second contact hole 9b Fourth contact hole 10 Second external electrode 10A Seed layer 10B External electrode layer 21 Through-hole for connecting external electrodes 22 External electrode connection member 22A Seed layer 22B External electrode connection layer 40 Original substrate 81 Main first external electrode 81A Seed layer 81B External electrode layer 82 Sub first external electrode 82A Seed layer 82B External electrode layer

Claims

【Claim 1】 a substrate having a first main surface on one side and a second main surface on the other side; a plurality of first internal electrode forming through-holes formed in a first region of the substrate, penetrating the substrate in the thickness direction, and having equal cross-sectional areas for each; a plurality of second internal electrode forming through-holes formed in the first region, penetrating the substrate in the thickness direction, and having equal cross-sectional areas for each; a plurality of external electrode connection through-holes formed in a second region different from the first region of the substrate, penetrating the substrate in the thickness direction, and having equal cross-sectional areas for each; a first internal electrode made of a conductor embedded in the first internal electrode forming through-hole; a second internal electrode made of a conductor embedded in the second internal electrode forming through-hole; an external electrode connection member made of a conductor embedded in the external electrode connection through-hole; a first insulating film formed on the first main surface so as to cover the end portion of the second internal electrode on the first main surface side, having a first contact hole for exposing the end portion of the first internal electrode on the first main surface side and a third contact hole for exposing the end portion of the external electrode connection member on the first main surface side; a second insulating film formed on the second main surface so as to cover the end portion of the first internal electrode on the second main surface side, having a second contact hole for exposing the end portion of the second internal electrode on the second main surface side and a fourth contact hole for exposing the end portion of the external electrode connection member on the second main surface side; a main first external electrode formed on the first main surface so as to cover the end portions of the plurality of first internal electrodes on the first main surface side and the end portion of the external electrode connection member on the first main surface side, and the plurality of first internal electrodes and the plurality of external electrode connection members being electrically connected; a second external electrode formed on the second main surface so as to cover the end portions of the plurality of second internal electrodes on the second main surface side, and the plurality of second internal electrodes being electrically connected; including a sub first external electrode formed on the second main surface so as to cover the end portions of the plurality of external electrode connection members on the second main surface side, and the plurality of external electrode connection members being electrically connected, wherein the plurality of first internal electrode forming through-holes, the plurality of second internal electrode forming through-holes, and the plurality of external electrode connection through-holes satisfy a first condition that the cross-sectional area of the first internal electrode forming through-hole, the cross-sectional area of the second internal electrode forming through-hole, and the cross-sectional area of the external electrode connection through-hole are equal; A second condition that the plurality of through-holes composed of all of the plurality of through-holes for forming the first internal electrodes, the plurality of through-holes for forming the second internal electrodes, and the plurality of through-holes for connecting external electrodes are arranged in a matrix so as to be aligned in a predetermined first direction parallel to the first main surface and a second direction parallel to the first main surface and orthogonal to the first direction in a plan view, and a third condition that the through-holes for forming the first internal electrodes and the through-holes for forming the second internal electrodes are alternately arranged in the first direction and also alternately arranged in the second direction, are satisfied. A capacitor. **Claim 2** The main first external electrode enters the first contact hole and is connected to the first internal electrode within the first contact hole, and also enters the third contact hole and is connected to the external electrode connection member within the third contact hole. The second external electrode enters the second contact hole and is connected to the second internal electrode within the second contact hole. The sub-first external electrode enters the fourth contact hole and is connected to the external electrode connection member within the fourth contact hole. The capacitor according to claim 1. **Claim 3** The aspect ratio of the through-holes for forming the first internal electrodes and the through-holes for forming the second internal electrodes is 50 or more. The capacitor according to claim 1. **Claim 4** The depths of the through-holes for forming the first internal electrodes, the through-holes for forming the second internal electrodes, and the external electrode connection member are 100 μm or more. The capacitor according to claim 1. **Claim 5** The maximum width or maximum diameter of the cross-section of the through-holes for forming the first internal electrodes, the through-holes for forming the second internal electrodes, and the external electrode connection member is 0.3 μm or more and 10 μm or less. The capacitor according to claim 4. **Claim 6** The electrode distance between the first internal electrode and the plurality of internal electrodes including the second internal electrode is 0.3 μm or more and 10 μm or less. The capacitor according to claim 4. **Claim 7** The conductor is composed of one arbitrarily selected from Cu, Al, Pt, Au, Ag, Ni, and polysilicon. The capacitor according to claim 1.

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