Metal particle film, method for producing metal particle film, and method for producing substrate having through electrode

Abstract

To provide a metal particle film, a method for manufacturing a metal particle film, and a method for manufacturing a substrate having a through electrode, which can efficiently form a conductor having sufficient conductivity.SOLUTION: A metal particle film 70 includes: a support film 71; and a metal particle-containing layer 72 provided on the support film 71, and containing metal particles and a volatile dispersion medium. The metal particle-containing layer 72 has a thickness of 100 μm or less and a metal particle concentration of 94 mass% or more.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a metal particle film, a method for producing a metal particle film, and a method for producing a substrate having a through electrode. [Background technology]

[0002] In recent years, in order to miniaturize, enhance the functionality, and integrate electronic devices and components, attention has been focused on three-dimensional packaging technology in which silicon substrates arranged above and below are electrically connected via electrodes called through-silicon vias (TSVs) on the silicon substrate, and semiconductor chips are densely stacked in the vertical direction (height direction).

[0003] As a method for forming a through-silicon electrode, for example, Patent Document 1 discloses a method for manufacturing a semiconductor device having a through-silicon electrode, which includes a step of electroplating a non-through via formed in a silicon substrate with copper using a specific copper plating solution. However, this method requires plating while suppressing the deposition rate of the copper film, which lengthens the working time and poses a problem in terms of productivity.

[0004] Another known method is to apply a metal paste, in which particles such as copper powder, fine copper powder, glass frit, etc. are dispersed in a dispersion medium, to a silicon substrate in which through-holes are formed, and fill the through-holes with the metal paste (for example, Patent Document 2 below). In this method, a conductor that serves as a through electrode is formed by firing the filled metal paste. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2019-16712 A [Patent Document 2] Patent No. 5376255 Summary of the Invention [Problem to be solved by the invention]

[0006] However, if the concentration of metal particles in the metal paste is increased in order to form a conductor with excellent conductivity, uncoated areas are likely to occur, and if a thick film is applied to prevent this, the loss of material tends to increase. On the other hand, if the concentration of metal particles in the metal paste is reduced, although the coatability improves, it tends to require a long drying time and to make it difficult to form a conductor with excellent conductivity. Therefore, it is difficult to achieve both conductor performance and production efficiency by simply adjusting the concentration of metal particles.

[0007] Therefore, one aspect of the present invention aims to provide a metal particle film that can efficiently form a conductor with sufficient conductivity, a method for manufacturing a metal particle film, and a method for manufacturing a substrate having a through electrode. [Means for solving the problem]

[0008] As a result of extensive research into achieving the above-mentioned object, the inventors discovered that by using a metal particle film having a metal particle-containing layer having a predetermined thickness and metal particle concentration provided on a support film, it is possible to efficiently form a conductor having sufficient conductivity in through holes or non-through holes, and thus completed the present invention.

[0009] That is, one aspect of the present disclosure provides the following invention. [1] A metal particle film comprising: a support film; and a metal particle-containing layer provided on the support film, the metal particle-containing layer containing metal particles and a volatile dispersion medium, wherein the metal particle-containing layer has a thickness of 100 μm or less and a metal particle concentration of 94 mass% or more. [2] The metal particle film according to [1], wherein the metal particles include copper particles. [3] The metal particle film according to [2], wherein the copper particles include first copper particles having a particle size of 0.8 μm or more and second copper particles having a particle size of 0.5 μm or less. [4] The metal particle film according to [3], wherein the first copper particles are flat. [5] The metal particle film according to any one of [2] to [4], wherein the metal particles further comprise solder particles. [6] The metal particle film according to [5], wherein the solder particles contain tin or a tin alloy. [7] The metal particle film according to [5], wherein the solder particles are In--Sn, In--Sn--Ag, Sn--Bi, Sn--Bi--Ag, Sn--Ag--Cu, or a Sn--Cu based alloy.

[0010] Further, other aspects of the present disclosure provide the following inventions. [8] A method for producing a metal particle film according to any one of [1] to [7], comprising the steps of: A step of applying a metal paste containing metal particles and a volatile dispersion medium, the metal particles having a concentration of less than 92 mass %, onto a support film to provide a metal paste layer; drying the metal paste layer to form a metal particle-containing layer having a thickness of 100 μm or less and a metal particle concentration of 94 mass % or more; A method for producing a metal particle film comprising: [9] The method for producing a metal particle film according to [8], wherein the metal paste is applied onto the support film by screen printing.

[0011] Further, other aspects of the present disclosure provide the following inventions.

[10] A method for producing a substrate having through electrodes, comprising: a preparation step of preparing an insulating substrate having through holes, the through holes communicating with both main surfaces; and a conductor formation step of forming a conductor in the through holes, the conductor formation step including a metal body formation step of forming a metal body having voids so as to fill at least the through holes, the metal body formation step including a filling step of pressing the metal particle film according to any one of [1] to [7] onto the substrate so that the metal particle-containing layer of the metal particle film is in contact with the substrate, to fill the through holes of the substrate with a metal particle composition; and a firing step of firing the metal particle composition to form a metal body.

[11] The method for manufacturing a substrate having a through electrode according to

[10] , wherein the conductor forming step further includes a resin impregnation step of impregnating the metal body with a curable resin composition, and a resin curing step of curing the curable resin composition impregnated into the metal body.

[12] A method for producing a substrate having a through electrode, comprising: a preparation step of preparing an insulating substrate having non-through holes, the substrate having one main surface on which the non-through holes are open; a conductor formation step of forming a conductor in the non-through holes; and a grinding step of providing a through electrode by grinding the side of the substrate having the conductor formed therein opposite to the surface on which the non-through holes are open, wherein the conductor formation step comprises a metal body formation step of forming a metal body having voids so as to fill at least the non-through holes, and the metal body formation step comprises a filling step of pressing the metal particle film according to any one of [1] to [7] against the substrate so that the metal particle-containing layer of the metal particle film is in contact with the substrate, thereby filling the non-through holes of the substrate with a metal particle composition; and a firing step of firing the metal particle composition to form a metal body.

[13] The method for manufacturing a substrate having a through electrode according to

[12] , wherein the conductor forming step further includes a resin impregnation step of impregnating the metal body with a curable resin composition, and a resin curing step of curing the curable resin composition impregnated into the metal body.

[14] A method for producing a substrate having a through electrode according to any one of

[10] to

[13] , further comprising a conductor removing step of removing at least a portion of the conductor formed on the main surface of the substrate.

[15] The method for producing a substrate having a through electrode according to any one of

[10] to

[14] , wherein the insulating substrate is a silicon wafer and the through electrode is a silicon through electrode. Effect of the Invention

[0012] According to one aspect of the present invention, it is possible to provide a metal particle film that can efficiently form a conductor with sufficient conductivity, a method for manufacturing a metal particle film, and a method for manufacturing a substrate having a through electrode. [Brief description of the drawings]

[0013] [Figure 1] FIG. 2 is a schematic diagram illustrating one embodiment of a metal particle film. [Diagram 2] 1A to 1C are schematic diagrams illustrating a method for producing a metal particle film. [Diagram 3] 2A to 2C are schematic diagrams illustrating a method for manufacturing a base body having a through electrode according to the first embodiment. [Figure 4] 2A to 2C are schematic diagrams illustrating a method for manufacturing a base body having a through electrode according to the first embodiment. [Diagram 5] 2A to 2C are schematic diagrams illustrating a method for manufacturing a base body having a through electrode according to the first embodiment. [Figure 6] 2A to 2C are schematic diagrams illustrating a method for manufacturing a base body having a through electrode according to the first embodiment. [Figure 7] 1A to 1C are schematic diagrams showing a method for manufacturing a substrate having a through electrode according to a first embodiment, and a substrate having a through electrode according to the first embodiment. [Figure 8] 1 is a schematic diagram showing a semiconductor device according to a first embodiment. [Figure 9] 5A to 5C are schematic diagrams illustrating a method for manufacturing a base body having a through electrode according to a second embodiment. [Figure 10] 5A to 5C are schematic diagrams showing a method for manufacturing a substrate having a through electrode according to a second embodiment, and a substrate having a through electrode according to the second embodiment. [Figure 11] FIG. 4 is a schematic diagram showing a semiconductor device according to a second embodiment. [Figure 12] FIG. 2 is a schematic diagram showing a test piece. [Figure 13] 13 is a cross-sectional photograph of a portion in which there is a void inside the solder (SnBi58) in the sample produced in Example 6. [Figure 14] 13 is a cross-sectional photograph of a portion of the sample produced in Example 6 in which there is a void on the outer periphery of the solder (SnBi58). [Figure 15] 1 is a cross-sectional photograph of a portion in which a crack exists inside a copper layer in a sample produced in Comparative Example 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following embodiments. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and duplicated explanations will be omitted.

[0015] (Metal Particle Film) The metal particle film of this embodiment includes a support film and a metal particle-containing layer that contains metal particles and a volatile dispersion medium and is provided on the support film. Fig. 1 is a schematic diagram showing one embodiment of a metal particle film. A metal particle film 70 shown in Fig. 1 includes a support film 71 and a metal particle-containing layer 72 that is provided on the support film 71. The metal particle film of this embodiment can be used for forming a conductor, and may also be used for forming a through electrode.

[0016] Examples of the support film 71 include a polyimide film, a polyethylene naphthalate film, and a polyethylene terephthalate film.

[0017] From the viewpoint of workability in forming a metal particle-containing layer by coating, the thickness of the support film 71 may be 20 to 200 μm, 25 to 175 μm, or 30 to 150 μm.

[0018] Examples of the metal particles include nickel, silver, copper, gold, palladium, platinum, solder, and the like. In this embodiment, the metal particle-containing layer may contain copper particles, or copper particles and solder particles, as the metal particles. When the metal particle-containing layer contains copper particles and solder particles, it is easy to obtain a conductor having sufficient conductivity and a resistance value that is unlikely to increase even when subjected to temperature changes, and a substrate having a through electrode having sufficient conductivity and excellent connection reliability.

[0019] The metal particle-containing layer may contain, as the copper particles, first copper particles having a particle size (maximum diameter) of 0.8 μm or more. The particle size (maximum diameter) of the first copper particles may be 1.0 μm or more, or 1.2 μm or more. The particle size (maximum diameter) of the first copper particles may be 10 μm or less, 9.0 μm or less, or 8.0 μm or less.

[0020] The average particle size (average maximum diameter) of the first copper particles may be 0.8 μm or more or 1.2 μm or more, and may be 10 μm or less or 8 μm or less, from the viewpoint of improving the sintering density in the through holes or non-through holes and suppressing the generation of voids in the through holes or non-through holes.

[0021] The particle size (maximum diameter) and average particle size (average maximum diameter) of the first copper particles can be obtained, for example, from an SEM image of the particles. A method for calculating the particle size (maximum diameter) of the first copper particles from an SEM image is exemplified. A powder of the first copper particles is placed on a carbon tape for SEM with a spatula to prepare a sample for SEM. This sample for SEM is observed at 5000 times magnification with an SEM device. A rectangle circumscribing the first copper particle in the SEM image is drawn with image processing software, and the long side of the rectangle is taken as the particle size (maximum diameter) of the particle. This measurement is performed on 50 or more first copper particles using multiple SEM images, and the average particle size (average maximum diameter) is calculated.

[0022] The shape of the first copper particles may be, for example, spherical, lump-like, needle-like, flat (flake-like), approximately spherical, etc. The first copper particles may be an aggregate of copper particles having these shapes.

[0023] The first copper particles are preferably flat (flake-shaped). In this case, it is preferable that the first copper particles are oriented approximately parallel to the interface between the metal particle-containing layer and the support film. This suppresses volumetric shrinkage when the copper particles filled in the through holes or non-through holes are sintered, making it easier to suppress voids occurring in the through holes or non-through holes. In addition, by suppressing volumetric shrinkage when the copper particles filled in the through holes or non-through holes are sintered, it is possible to suppress cracks in the metal body formed on at least one main surface of the base (e.g., silicon substrate).

[0024] The aspect ratio of the first copper particles may be 4 or more, 5 or more, or 6 or more. If the aspect ratio is within the above range, the first copper particles in the metal particle-containing layer are easily oriented parallel to the interface between the metal particle-containing layer and the support film, and the volume shrinkage can be suppressed when the metal particle composition filled in the through holes or non-through holes is sintered. This makes it possible to further suppress disconnection of the wiring due to thermal stress when wiring is formed from a conductor provided on the main surface of a substrate (e.g., a silicon substrate). In addition, the adhesion between the metal body and the metal coating formed on the substrate (e.g., a silicon substrate) can be improved. The aspect ratio (major axis / thickness) of the copper particles in the metal particle-containing layer can be determined, for example, by observing an SEM image of the particles and measuring the major axis and thickness.

[0025] The metal particle-containing layer preferably contains first copper particles having a particle size (maximum diameter) of 0.8 μm or more and 10 μm or less and an aspect ratio of 4 or more. By containing such first copper particles in the metal particle-containing layer, the volume shrinkage when the metal particle composition filled in the through holes or non-through holes is sintered can be sufficiently reduced, and it becomes easy to form a metal body having a porous structure and a sufficiently formed conductive network in the through holes or non-through holes. As a result, it is possible to suppress the generation of voids in the through holes or non-through holes, and to form a metal body that is less likely to crack on the main surface of the base (e.g., a silicon substrate), and when wiring is formed from a conductor containing this metal body, breakage of the wiring due to thermal stress can be further suppressed.

[0026] The metal particle-containing layer may contain copper particles having a particle size (maximum diameter) of 0.8 μm or more and 10 μm or less and an aspect ratio of less than 2, but the content of the copper particles having a particle size (maximum diameter) of 0.8 μm or more and 10 μm or less and an aspect ratio of less than 2 is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, and even more preferably 30 parts by mass or less, relative to 100 parts by mass of the first copper particles having a particle size (maximum diameter) of 0.8 μm or more and 10 μm or less and an aspect ratio of 4 or more. By limiting the content of the copper particles having a particle size (maximum diameter) of 0.8 μm or more and 10 μm or less and an aspect ratio of less than 2, it is possible to form a metal body having a porous structure and a sufficiently formed conductive network in the through holes or non-through holes while suppressing the generation of voids in the through holes by the first copper particles in the metal particle composition filled in the through holes or non-through holes. Furthermore, on the main surface of the base (e.g., a silicon substrate), the first copper particles tend to be oriented approximately parallel to the main surface of the base, and volumetric shrinkage can be more effectively suppressed to form a metal body that is less susceptible to cracking.When wiring is formed from a conductor including this metal body, breakage of the wiring due to thermal stress can be further suppressed.

[0027] In order to make such effects more easily obtainable, the content of copper particles having a particle size (maximum diameter) of 0.8 μm or more and 10 μm or less and an aspect ratio of less than 2 may be 20 parts by mass or less, 10 parts by mass or less, or even 0 parts by mass per 100 parts by mass of first copper particles having a particle size (maximum diameter) of 0.8 μm or more and 10 μm or less and an aspect ratio of 4 or more.

[0028] The content of the first copper particles in the metal particle-containing layer may be 15 mass% or more, 20 mass% or more, or 50 mass% or more, and may be 85 mass% or less, 70 mass% or less, or 50 mass% or less, based on the total mass of the metal particles contained in the metal particle-containing layer. When the content of the first copper particles is within the above range, the above-mentioned effects are more easily obtained.

[0029] The first copper particles may be treated with a surface treatment agent from the viewpoint of dispersion stability and oxidation resistance. The surface treatment agent may be one that is removed during wiring formation (when sintering the copper particles). Examples of such surface treatment agents include aliphatic carboxylic acids such as palmitic acid, stearic acid, arachidic acid, and oleic acid; aromatic carboxylic acids such as terephthalic acid, pyromellitic acid, and o-phenoxybenzoic acid; aliphatic alcohols such as cetyl alcohol, stearyl alcohol, isobornylcyclohexanol, and tetraethylene glycol; aromatic alcohols such as p-phenylphenol; alkylamines such as octylamine, dodecylamine, and stearylamine; aliphatic nitriles such as stearonitrile and decanenitrile; silane coupling agents such as alkylalkoxysilanes; and polymer treatment agents such as polyethylene glycol, polyvinyl alcohol, polyvinylpyrrolidone, and silicone oligomers. The surface treatment agents may be used alone or in combination of two or more.

[0030] The amount of the surface treatment agent may be an amount of one molecular layer or more on the particle surface. The amount of the surface treatment agent varies depending on the specific surface area of ​​the first copper particles, the molecular weight of the surface treatment agent, and the minimum coverage area of ​​the surface treatment agent. The amount of the surface treatment agent is usually 0.001 mass% or more.

[0031] The amount of the surface treatment agent is determined by the number of molecular layers (n) attached to the surface of the first copper particles and the specific surface area (A p ) (unit: m 2 / g) and the molecular weight of the surface treatment agent (M s ) (unit: g / mol) and the minimum coverage area of ​​the surface treatment agent (S S ) (unit: m 2 / piece) and Avogadro's number (N A )(6.02×10 23 Specifically, the amount of surface treatment agent can be calculated by the amount of surface treatment agent (mass%) = {(n·A p M s ) / (S S N A +n·A p M s )}×100%.

[0032] The specific surface area of ​​the first copper particles can be calculated by measuring the dried copper particles using a BET specific surface area measurement method. The minimum coverage area of ​​the surface treatment agent is 2.05 × 10 -19 m 2 The carbon content of the surface treatment agent is 1 / molecule. In the case of other surface treatment agents, it can be measured, for example, by calculation from a molecular model or by the method described in "Chemistry and Education" (Katsuhiro Ueda, Sumio Inafuku, Iwao Mori, 40(2), 1992, p114-117). An example of a method for quantifying the surface treatment agent is shown below. The surface treatment agent can be identified by a thermal desorption gas-gas chromatograph mass spectrometer of the dried powder obtained by removing the dispersing medium from the metal paste, and the carbon number and molecular weight of the surface treatment agent can be determined. The carbon content of the surface treatment agent can be analyzed by carbon content analysis. Examples of carbon content analysis methods include high-frequency induction heating furnace combustion / infrared absorption method. The amount of the surface treatment agent can be calculated from the carbon number, molecular weight and carbon content of the identified surface treatment agent using the above formula.

[0033] The first copper particles can be commercially available. Examples of commercially available first copper particles include MA-C025 (manufactured by Mitsui Mining & Smelting Co., Ltd., average particle size 4.1 μm), 3L3 (manufactured by Fukuda Metal Foil & Powder Co., Ltd., average particle size 7.3 μm), 1110F (manufactured by Mitsui Mining & Smelting Co., Ltd., average particle size 5.8 μm), and 2L3 (manufactured by Fukuda Metal Foil & Powder Co., Ltd., average particle size 9 μm).

[0034] When forming the metal particle-containing layer, the copper particles may include first copper particles having a particle size (maximum diameter) of 0.8 μm or more and 10 μm or less and an aspect ratio of 4 or more, and the content of the copper particles having a particle size (maximum diameter) of 0.8 μm or more and 10 μm or less and an aspect ratio of less than 2 is 50 parts by mass or less, preferably 40 parts by mass or less, more preferably 30 parts by mass or less per 100 parts by mass of the first copper particles having a particle size (maximum diameter) of 0.8 μm or more and 10 μm or less and an aspect ratio of 4 or more. A commercially available product made of such copper particles may be selected and used.

[0035] When the metal particle film is used to form a through electrode, the ratio (maximum diameter) of the pore size of the through hole to the particle size (maximum diameter) of the first copper particle (pore size (μm) / particle size (μm)) may be 4 or more, 8 or more, or 10 or more, and may be 150 or less, 100 or less, or 50 or less, from the viewpoint of suppressing volumetric shrinkage and forming a metal body that is less susceptible to cracking. When the metal particle film is applied to a base having non-through holes, the ratio (maximum diameter) of the pore size of the non-through hole to the particle size (maximum diameter) of the first copper particle (pore size (μm) / particle size (μm)) can be set so that the ratio (maximum diameter) of the pore size of the silicon through electrode to be formed to the particle size (maximum diameter) of the first copper particle is within the above range.

[0036] In one embodiment, the metal particle-containing layer can include the above-mentioned first copper particles and second copper particles having a particle size (maximum diameter) of 0.5 μm or less. In this case, when the copper particles are sintered, the second copper particles are interposed between the first copper particles, which tends to improve the conductivity of the resulting wiring. That is, it is preferable to use the first copper particles and the second copper particles in combination. When forming a metal particle-containing layer containing only the second copper particles as copper particles, the volume shrinkage and sintering shrinkage accompanying drying of the dispersion medium are large, so that when the copper particles are sintered, the sintered body is easily peeled off from the metal coating provided on the insulating base (e.g., silicon wafer), and sufficient airtightness and connection reliability are difficult to obtain. However, by using the first copper particles and the second copper particles in combination, the volume shrinkage when the metal particle composition filled in the through holes or non-through holes is sintered is suppressed, and the adhesion between the metal body formed in the through holes or non-through holes and the metal coating formed on the wall surface of the through holes or non-through holes can be improved. This makes it more difficult for the copper sintered body in the through hole to break due to thermal stress, and further improves the airtightness and connection reliability against thermal stress.

[0037] The second copper particles can act as copper particles that suitably bond the first copper particles together. In addition, the second copper particles have better sinterability than the first copper particles, and can have the function of promoting the sintering of the copper particles. For example, compared to the case where the first copper particles are used alone as the copper particles, it is possible to sinter the copper particles at a lower temperature. In addition, when forming a metal particle-containing layer containing only the second copper particles as the copper particles, the volume shrinkage and sintering shrinkage accompanying drying of the dispersion medium are large, so that the metal body formed inside the through holes or non-through holes is likely to cause voids inside the through holes or non-through holes due to the volume shrinkage. In particular, by using the flat first copper particles and the second copper particles in combination, the flat first copper particles act as copper particles that are suitably bonded by the second copper particles, and it is therefore easy to form a metal body having voids (porous structure) while suppressing the generation of voids inside the through holes.

[0038] The average particle size (average maximum diameter) of the second copper particles contained in the metal particle-containing layer may be 0.01 μm or more, 0.03 μm or more, 0.05 μm or more, or 0.08 μm or more, and may be 0.5 μm or less, 0.4 μm or less, 0.3 μm or less, or 0.2 μm or less.

[0039] If the average particle size (average maximum diameter) of the second copper particles is 0.01 μm or more, the effects of suppressing the synthesis cost of the second copper particles, good dispersibility, and suppressing the amount of surface treatment agent used are easily obtained. If the average particle size (average maximum diameter) of the second copper particles is 0.5 μm or less, the effect of excellent sinterability of the second copper particles is easily obtained. From the viewpoint of further achieving the above effect, the average particle size (average maximum diameter) of the second copper particles may be 0.05 μm or more, 0.1 μm or more, or 0.2 μm or more, and may be 0.5 μm or less, 0.4 μm or less, or 0.3 μm or less.

[0040] The second copper particles may contain 20% by mass or more of copper particles having a particle size (maximum diameter) of 0.01 μm or more and 0.5 μm or less. From the viewpoint of sinterability of the metal particle composition filled in the through holes or non-through holes, the second copper particles may contain 30% by mass or more, 50% by mass or more, or 85% by mass or less of copper particles having a particle size of 0.01 μm or more and 0.5 μm or less. When the content ratio of copper particles having a particle size (maximum diameter) of 0.01 μm or more and 0.5 μm or less in the second copper particles is 20% by mass or more, the dispersibility of the copper particles is further improved, and the increase in the viscosity of the metal paste used in forming the metal particle-containing layer and the decrease in the paste concentration can be further suppressed.

[0041] The content of the second copper particles in the metal particle-containing layer may be 20% by mass or more, 30% by mass or more, 35% by mass or more, or 40% by mass or more, and 85% by mass or less, 80% by mass or less, or 75% by mass or less, based on the total mass of the metal particles contained in the metal particle-containing layer. If the content of the second copper particles is within the above range, it is easy to form a metal body having excellent adhesion to a metal coating provided on a base (e.g., a silicon substrate) while suppressing the generation of voids in the through holes or non-through holes, and a copper sintered body that is less likely to crack on the main surface of the base (e.g., a silicon substrate) can be formed, and when wiring is formed from a conductor containing this copper sintered body, breakage of the wiring due to thermal stress can be further suppressed.

[0042] The content of the second copper particles in the metal particle-containing layer may be 20% by mass or more and 85% by mass or less based on the total mass of the first copper particles and the second copper particles. If the content of the second copper particles is 20% by mass or more, the spaces between the first copper particles can be sufficiently filled, a metal body that is less likely to crack can be formed, and the wiring formed from the conductor containing this metal body is less likely to break due to thermal stress. If the content of the second copper particles is 85% by mass or less, the volumetric shrinkage when the copper particles are sintered can be sufficiently suppressed, so that the generation of voids in the through holes or non-through holes can be suppressed, and a metal body that is less likely to crack can be formed, and the wiring formed from the conductor containing this metal body is less likely to break due to thermal stress.

[0043] From the viewpoint of making the above-mentioned effect more easily obtainable, the content of the second copper particles may be 30 mass% or more, 35 mass% or more, or 40 mass% or more, and may be 85 mass% or less, or 80 mass% or less, based on the sum of the mass of the first copper particles and the mass of the second copper particles.

[0044] The shape of the second copper particles may be, for example, spherical, blocky, needle-like, flat (flake-like), approximately spherical, etc. The second copper particles may be an aggregate of copper particles having these shapes. From the viewpoint of dispersibility and packing property, the shape of the second copper particles may be spherical, approximately spherical, or flat (flake-like), and from the viewpoint of combustibility and mixability with the first copper particles, etc., the shape of the second copper particles may be spherical or approximately spherical.

[0045] The aspect ratio of the second copper particles may be 5 or less, 4 or less, or 3 or less, from the viewpoints of dispersibility, packing property, and mixability with the first copper particles.

[0046] The second copper particles may be treated with a specific surface treatment agent. Examples of the specific surface treatment agent include organic acids having 8 to 16 carbon atoms. Examples of the organic acids having 8 to 16 carbon atoms include caprylic acid, methylheptanoic acid, ethylhexanoic acid, propylpentanoic acid, pelargonic acid, methyloctanoic acid, ethylheptanoic acid, propylhexanoic acid, capric acid, methylnonanoic acid, ethyloctanoic acid, propylheptanoic acid, butylhexanoic acid, undecanoic acid, methyldecanoic acid, ethylnonanoic acid, propyloctanoic acid, butylheptanoic acid, lauric acid, methylundecanoic acid, ethyldecanoic acid, propylnonanoic acid, butyloctanoic acid, Saturated fatty acids such as pentylheptanoic acid, tridecanoic acid, methyldodecanoic acid, ethylundecanoic acid, propyldecanoic acid, butylnonanoic acid, pentyloctanoic acid, myristic acid, methyltridecanoic acid, ethyldodecanoic acid, propylundecanoic acid, butyldecanoic acid, pentylnonanoic acid, hexyloctanoic acid, pentadecanoic acid, methyltetradecanoic acid, ethyltridecanoic acid, propyldodecanoic acid, butylundecanoic acid, pentyldecanoic acid, hexylnonanoic acid, palmitic acid, methylpentadecanoic acid, ethyltetradecanoic acid, propyltridecanoic acid, butyldodecanoic acid, pentylundecanoic acid, hexyldecanoic acid, heptylnonanoic acid, methylcyclohexanecarboxylic acid, ethylcyclohexanecarboxylic acid, propylcyclohexanecarboxylic acid, butylcyclohexanecarboxylic acid, pentylcyclohexanecarboxylic acid, hexylcyclohexanecarboxylic acid, heptylcyclohexanecarboxylic acid, octylcyclohexanecarboxylic acid, and nonylcyclohexanecarboxylic acid; octene Examples of the organic acid include unsaturated fatty acids such as benzoic acid, nonenoic acid, methylnonenoic acid, decenoic acid, undecenoic acid, dodecenoic acid, tridecenoic acid, tetradecenoic acid, myristoleic acid, pentadecenoic acid, hexadecenoic acid, palmitoleic acid, and sabienoic acid; and aromatic carboxylic acids such as terephthalic acid, pyromellitic acid, o-phenoxybenzoic acid, methylbenzoic acid, ethylbenzoic acid, propylbenzoic acid, butylbenzoic acid, pentylbenzoic acid, hexylbenzoic acid, heptylbenzoic acid, octylbenzoic acid, and nonylbenzoic acid. The organic acid may be used alone or in combination of two or more.By combining such an organic acid with the second copper particles, it tends to be possible to achieve both the dispersibility of the second copper particles and the desorption property of the organic acid during sintering.

[0047] The amount of the surface treatment agent may be an amount that adheres to the surface of the second copper particles in a monolayer to trilayer form. The amount of the surface treatment agent may be 0.07% by mass or more, 0.10% by mass or more, or 0.2% by mass or more, and may be 2.1% by mass or less, 1.6% by mass or less, or 1.1% by mass or less. The amount of the surface treatment agent of the second copper particles can be calculated by the method described above for the first copper particles. The same applies to the specific surface area, the molecular weight of the surface treatment agent, and the minimum coverage area of ​​the surface treatment agent.

[0048] As the second copper particles, either synthetic or commercially available particles can be used.

[0049] The sum of the content of the first copper particles and the content of the second copper particles in the metal particle-containing layer may be 70 mass% or more, 80 mass% or more, 90 mass% or more, 93 mass% or more, or 95 mass% or more based on the total mass of the metal particles contained in the metal particle-containing layer. When the sum of the content of the first copper particles and the content of the second copper particles is within the above range, it is easy to suppress the generation of voids in the through holes or non-through holes.

[0050] The solder particles may contain tin or a tin alloy, such as In-Sn, In-Sn-Ag, Sn-Bi, Sn-Bi-Ag, Sn-Ag-Cu, or Sn-Cu alloys, including the following examples: In-Sn (In 52% by mass, Bi 48% by mass, melting point: 118°C) ·In-Sn-Ag (In20% by mass, Sn77.2% by mass, Ag2.8% by mass, melting point: 175℃) Sn-Bi (Sn 43% by mass, Bi 57% by mass, melting point: 138°C) Sn-Bi-Ag (Sn 42% by mass, Bi 57% by mass, Ag 1% by mass, melting point: 139°C) ·Sn-Ag-Cu (96.5% by mass of Sn, 3% by mass of Ag, 0.5% by mass of Cu, melting point: 217℃) Sn-Cu (Sn 99.3% by mass, Cu 0.7% by mass, melting point: 227°C)

[0051] The metal particle-containing layer may contain, as the solder particles, solder particles having a particle size (maximum diameter) of 1.0 μm or more, for example.

[0052] The particle size (maximum diameter) of the solder particles may be 1.5 μm or more, 2 μm or more, or 15 μm or less, 10 μm or less, or 8.0 μm or less.

[0053] The average particle size (average maximum diameter) of the solder particles contained in the metal particle-containing layer may be 1.0 μm or more, 1.5 μm or more, 2.0 μm or more, 15 μm or less, 10 μm or less, or 8.0 μm or less, from the viewpoint of suppressing the volume shrinkage due to sintering in the through holes and suppressing the generation of voids in the through holes. By using such a particle size of the solder particles, the volume shrinkage when the copper particles in the metal particle composition are sintered can be sufficiently reduced, and it becomes easy to form a metal body having a porous structure and a sufficiently formed conductive network in the through holes or non-through holes. As a result, it is possible to suppress the generation of voids in the through holes or non-through holes, and it is possible to form a metal body that is less likely to crack on the main surface of the base (e.g., silicon substrate), and when wiring is formed from a conductor containing this metal body, it is possible to further suppress breakage of the wiring due to thermal stress.

[0054] The particle size of the solder particles is preferably uniform. In this case, the solder particles are easily dispersed in the metal body, and voids are generated inside the dispersed solder or in the outer periphery of the solder (between the solder and the copper sintered body), which suppresses the generation of continuous voids and cracks with a length of 5 μm or more, and prevents breaks in the vias and breaks in the wiring formed on the main surface of the base (e.g., silicon substrate).

[0055] The particle size (maximum diameter) and average particle size (average maximum diameter) of solder particles can be calculated from an SEM image, for example, by the following procedure. A powder of solder particles is placed on a carbon tape for SEM with a spatula to prepare an SEM sample. This SEM sample is observed at 5000x magnification with an SEM device. A rectangle circumscribing the solder particle in the SEM image is drawn using image processing software, and the long side of the rectangle is taken as the particle size (maximum diameter) of that particle. This measurement is performed on 50 or more solder particles using multiple SEM images, and the average particle size (average maximum diameter) is calculated.

[0056] The shape of the solder particles may be, for example, spherical, lump-like, needle-like, flat (flake-like), approximately spherical, etc. The solder particles may also be an aggregate of solder particles having these shapes.

[0057] The solder particles are preferably spherical. In this case, the solder particles are uniformly dispersed inside the metal body, and voids are generated inside the uniformly dispersed solder or in the outer periphery of the solder (between the solder and the copper sintered body), which suppresses the volumetric shrinkage when the copper particles in the metal particle composition are sintered, and makes it easy to suppress the breakage that occurs in the through hole. In addition, by suppressing the volumetric shrinkage when the copper particles in the metal particle composition are sintered, it is possible to suppress cracks in the metal body formed on at least one main surface of the base (e.g., silicon substrate).

[0058] The content of the solder particles in the metal particle-containing layer may be 1 part by mass or more, 2 parts by mass or more, or 3 parts by mass or more, and 25 parts by mass or less, 20 parts by mass or less, or 15 parts by mass or less, relative to 100 parts by mass of the copper particles contained in the metal particle-containing layer. If the content of the solder particles is within the above range, the above-mentioned effect is more easily obtained. That is, it is easy to form a metal body in which a conductive network is sufficiently formed while having a porous structure, in a through hole or a non-through hole, while suppressing the generation of voids in the through hole. In addition, when the metal particle-containing layer contains the above-mentioned first copper particles, the first copper particles are easily oriented approximately parallel to the main surface of the base (e.g., a silicon substrate) on the main surface of the base, and volume shrinkage is more effectively suppressed to form a metal body that is less likely to crack, and when wiring is formed from a conductor containing this metal body, breakage of the wiring due to thermal stress can be further suppressed. If the content of the solder particles is 1 part by mass or more per 100 parts by mass of the copper particles, it becomes easier to suppress the generation of voids inside the metal body, and it becomes easier to prevent, for example, the generation of cracks longer than 5 μm and the occurrence of disconnections inside the vias. On the other hand, if the content of the solder particles is 25 parts by mass or less per 100 parts by mass of the copper particles, the resistivity of the wiring becomes difficult to increase.

[0059] The total content of the copper particles (preferably the content of the first copper particles and the content of the second copper particles) and the solder particles in the metal particle-containing layer may be 80 mass% or more, or 90 mass% or more, based on the total mass of the metal particles contained in the metal particle-containing layer. In this case, it is easier to suppress the generation of voids in the through holes or non-through holes. From the viewpoint of making such an effect more easily obtainable, the total content of the copper particles (preferably the content of the first copper particles and the content of the second copper particles) and the solder particles may be 95 mass% or more, or 100 mass%, based on the total mass of the metal particles.

[0060] The average particle size (maximum diameter) of the other metal particles other than the copper particles and the solder particles may be 0.01 μm or more, 0.03 μm or more, or 0.05 μm or more, and may be 5 μm or less, 3.0 μm or less, or 2.0 μm or less. When the metal particle-containing layer contains other metal particles, the content thereof may be less than 20 mass%, 15 mass% or less, or 10 mass% or less based on the total mass of the metal particles contained in the metal particle-containing layer from the viewpoint of obtaining sufficient bonding properties. The other metal particles may not be contained. The shape of the other metal particles is not particularly limited.

[0061] The volatile dispersion medium contained in the metal particle-containing layer is not particularly limited, and examples thereof include monohydric and polyhydric alcohols such as pentanol, hexanol, heptanol, octanol, decanol, ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, α-terpineol, and isobornylcyclohexanol (MTPH); ethylene glycol butyl ether, ethylene glycol phenyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol butyl ether, diethylene glycol isobutyl ether, diethylene glycol hexyl ether, triethylene glycol methyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl methyl ether, diethylene glycol isopropyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol butyl methyl ether, and propylene glycol propyl ether. Examples of the esters include dipropylene glycol methyl ether, dipropylene glycol ethyl ether, dipropylene glycol propyl ether, dipropylene glycol butyl ether, dipropylene glycol dimethyl ether, tripropylene glycol methyl ether, and tripropylene glycol dimethyl ether; esters such as ethylene glycol ethyl ether acetate, ethylene glycol butyl ether acetate, diethylene glycol ethyl ether acetate, diethylene glycol butyl ether acetate, dipropylene glycol methyl ether acetate (DPMA), ethyl lactate, butyl lactate, γ-butyrolactone, and propylene carbonate; acid amides such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, and N,N-dimethylformamide; aliphatic hydrocarbons such as cyclohexane, octane, nonane, decane, and undecane; aromatic hydrocarbons such as benzene, toluene, and xylene; mercaptans having an alkyl group having 1 to 18 carbon atoms; and mercaptans having a cycloalkyl group having 5 to 7 carbon atoms.Examples of mercaptans having an alkyl group having 1 to 18 carbon atoms include ethyl mercaptan, n-propyl mercaptan, i-propyl mercaptan, n-butyl mercaptan, i-butyl mercaptan, t-butyl mercaptan, pentyl mercaptan, hexyl mercaptan, and dodecyl mercaptan. Examples of mercaptans having a cycloalkyl group having 5 to 7 carbon atoms include cyclopentyl mercaptan, cyclohexyl mercaptan, and cycloheptyl mercaptan.

[0062] The content of the dispersion medium in the metal particle-containing layer can be set so that the concentration of metal particles in the metal particle-containing layer is 94 mass % or more.

[0063] From the viewpoint of suppressing voids and cracks in the sintered layer after sintering, the metal particle-containing layer may have a metal particle concentration of 80 to 97 mass %, or 90 to 96 mass %.

[0064] If necessary, the metal particle-containing layer may appropriately contain additives such as wetting improvers such as nonionic surfactants and fluorine-based surfactants, antifoaming agents such as silicone oils, and ion trapping agents such as inorganic ion exchangers.

[0065] The thickness of the metal particle-containing layer (T1 shown in FIG. 1) is preferably 100 μm or less, but is not limited thereto. From the viewpoint of easily ensuring sufficient filling of the through holes or non-through holes, the thickness of the metal particle-containing layer may be 30 μm or more, 40 μm or more, or 50 μm or more.

[0066] From the viewpoint of suppressing the occurrence of voids in the through holes or non-through holes, the metal particle-containing layer may have a waviness (height difference) of 20 μm or less on the surface (S shown in FIG. 1) opposite the support film, or may have a waviness (height difference) of 10 μm or less. By reducing the waviness (height difference), when the metal particle film is pressed to fill the through holes of the substrate with a metal particle composition, it becomes easier to simultaneously fill the numerous through holes or non-through holes present in the substrate, and it becomes easier to reduce the number of through holes or non-through holes that are completely unfilled and the number of through holes or non-through holes where voids are partially generated. The waviness (height difference) can be evaluated by a non-contact method using a laser displacement meter or the like.

[0067] (Metal Particle Film Manufacturing Method) The above-mentioned metal particle film can be obtained by a method comprising the steps of applying a metal paste, which contains metal particles and a volatile dispersion medium and has a metal particle concentration of less than 92 mass %, onto a support film to provide a metal paste layer, and drying the metal paste layer to form a metal particle-containing layer having a thickness of 100 μm or less and a metal particle concentration of 94 mass % or more.

[0068] According to the method of this embodiment, it is easy to form a metal particle-containing layer in which the waviness (height difference) on the surface (S shown in FIG. 1) opposite to the support film is 10 μm or less.

[0069] The support film, metal particles, and volatile dispersion medium can be those described above. The composition of the metal particles and volatile dispersion medium in the metal paste can be appropriately set so as to satisfy the conditions for the metal particle-containing layer described above.

[0070] The concentration of metal particles in the metal paste may be 70% by mass or more, 75% by mass or more, 80% by mass or more, or 85% by mass or more, and may be less than 92% by mass, 90% by mass or less, or 88% by mass or less.

[0071] The metal paste can be prepared by mixing copper particles, solder particles, and optional components (additives, other metal particles, etc.) in a dispersion medium. After mixing the components, a stirring process may be performed. The maximum particle size of the dispersion may be adjusted by a classification operation.

[0072] When the metal paste contains the above-mentioned first copper particles and second particles, the second copper particles, the surface treatment agent, and the dispersion medium may be mixed in advance, and a dispersion liquid of the second copper particles may be prepared by performing a dispersion treatment, and the first copper particles, the solder particles, and other metal particles and optional additives may be further mixed to prepare the metal paste. By adopting such a procedure, the dispersibility of the second copper particles is improved, and the mixability with the first copper particles is improved, and the performance of the metal paste is further improved. The dispersion liquid of the second copper particles may be subjected to a classification operation to remove aggregates.

[0073] Methods for applying the metal paste include, for example, screen printing, transfer printing, offset printing, jet printing, and methods using a dispenser, jet dispenser, needle dispenser, comma coater, slit coater, die coater, gravure coater, slit coat, letterpress printing, intaglio printing, gravure printing, stencil printing, soft lithography, bar coat, applicator, particle deposition method, spray coater, spin coater, dip coater, etc.

[0074] 2A and 2B are schematic diagrams showing a method for producing a metal particle film, in which (a) of Fig. 2 shows a state in which metal paste 73 is applied to support film 71 by applicator 74.

[0075] From the viewpoints of ease of application and uniformity of the applied film thickness, the metal paste can be applied onto the support film by screen printing.

[0076] As shown in FIG. 2(b), a metal paste layer 73 is formed by applying a metal paste.

[0077] The thickness of the metal paste layer (T2 shown in (b) of FIG. 2) may be 1 μm or more, 2 μm or more, 3 μm or more, 5 μm or more, 10 μm or more, 15 μm or more, or 20 μm or more, and may be 300 μm or less, 250 μm or less, 200 μm or less, 150 μm or less, 120 μm or less, 100 μm or less, 80 μm or less, or 50 μm or less.

[0078] The step of drying the metal paste layer to form the metal particle-containing layer can be carried out at room temperature or at a temperature between room temperature and 100° C. or lower, and the atmosphere may be air or nitrogen.

[0079] As shown in FIG. 2(c), the metal paste layer is dried to form the metal particle-containing layer 72 described above.

[0080] Next, a method for producing a substrate having through electrodes using the metal particle film according to this embodiment will be described.

[0081] (Method for manufacturing a substrate having a through electrode according to the first embodiment) 3 to 7 are schematic diagrams showing a method for manufacturing a base body having a through electrode according to the first embodiment.

[0082] The method for manufacturing a substrate having a through electrode according to the first embodiment includes a preparation step of preparing a substrate having an insulating substrate with through holes and the through holes communicate with both main surfaces, and a conductor formation step of forming a conductor in the through holes, the conductor formation step includes a metal body formation step of forming a metal body having voids so as to fill at least the through holes, and the metal body formation step includes a filling step of pressing the metal particle film of this embodiment onto the substrate so that the metal particle-containing layer of the metal particle film contacts the substrate, filling the through holes of the substrate with a metal particle composition, and a firing step of firing the metal particle composition to form a metal body. In the method of this embodiment, the conductor formation step further includes a resin impregnation step of impregnating the metal body with a curable resin composition, and a resin curing step of curing the curable resin composition impregnated into the metal body.

[0083] The method according to the first embodiment will be described by taking as an example a case in which a silicon substrate having an insulating substrate of a silicon wafer is prepared as a substrate, and a substrate having a silicon through electrode (hereinafter, sometimes referred to as a silicon through electrode substrate) is manufactured as a substrate having a through electrode, but in the following description, the silicon wafer may be replaced with another insulating substrate. Examples of other insulating substrates include a glass substrate, a ceramic substrate, a printed wiring board, and a semiconductor package substrate.

[0084] <Substrate preparation process> 3(a), a silicon substrate 40 can be prepared, which has a silicon wafer 1 with a through hole 30 formed therein, and a metal coating 2 formed on the wall surface of the through hole and on the surface of the silicon wafer 1. The through hole 30 communicates with both main surfaces of the silicon substrate 40.

[0085] The thickness of the silicon wafer 1 may be 100 μm or more, 200 μm or more, or 300 μm or more from the viewpoint of suppressing warping of the substrate after sintering, and may be 800 μm or less, 300 μm or less, 200 μm or less, or 100 μm or less from the viewpoint of reducing the weight and increasing the density of the substrate.

[0086] The upper limit of the hole diameter of the through hole 30 may be 200 μm or less, 100 μm or less, or 60 μm or less from the viewpoint of increasing the density of the resulting semiconductor device, and the lower limit of the hole diameter of the through hole 30 is not particularly limited, but may be 20 μm or more, 30 μm or more, or 50 μm or more.

[0087] The number of through holes 30 provided in the silicon substrate 40 is set per 1 cm 2 of the main surface of the substrate in order to increase the density of the resulting semiconductor device. 2 There may be 100 or more, 200 or more, or 300 or more per unit area.

[0088] The metal coating 2 may be provided on both main surfaces of the silicon wafer 1 and on the wall surface of the through hole 30, or may be provided on at least one main surface of the silicon wafer 1 and on the wall surface of the through hole 30, or may be provided only on the wall surface of the through hole 30, or may not be provided at all. In the embodiment shown in (a) of FIG. 3, a silicon substrate 40 has a metal coating 2 on both main surfaces of the silicon wafer 1 and on the wall surface of the through hole 30.

[0089] Examples of the metal coating 2 include titanium, nickel, chromium, copper, aluminum, palladium, platinum, and gold. From the viewpoint of adhesion, the metal coating 2 is preferably a coating in which titanium, nickel, and copper are layered in this order. Adhesion is improved by oxidizing the surface of the silicon wafer 1 to silicon oxide and forming a titanium layer on the silicon oxide. Furthermore, by providing a nickel layer on the titanium layer and then a copper layer on the nickel layer, diffusion of copper into the silicon wafer 1 can be suppressed compared to the case where a copper layer is directly provided on the titanium layer. Furthermore, by providing a copper layer on the surface, adhesion between the metal body formed in the metal body forming step described below and the silicon substrate 40 is improved.

[0090] <Metal body formation process> The metal body forming step may include the following filling step and firing step.

[0091] <Filling process> In this step, the metal particle film 70 of the present embodiment described above is pressed against the silicon substrate 40 so that the metal particle-containing layer 72 of the metal particle film is in contact with the silicon substrate 40, and the metal particle composition 3 is filled into the through-holes 30 of the silicon substrate 40. When the metal particle-containing layer contains copper particles, or copper particles and solder particles, the metal particle composition containing copper particles, or copper particles and solder particles, is filled.

[0092] In the filling step, for example, as shown in (a) and (b) of FIG. 3, the metal particle film 70 and the silicon substrate 40 can be sandwiched and pressurized from above and below by a pressing tool A. The pressing tool A is not particularly limited, and may be a commercially available one, and may also be made using a metal member having a flat portion. For example, a pressing tool having two or more of the above-mentioned metal members can press the metal particle film against the silicon substrate by sandwiching the metal particle film and the silicon substrate between the metal members arranged so that the flat portions face each other. The pressing tool A may have a mechanism for adjusting the pressure applied to the metal particle film and the silicon substrate. A spring or the like can be used as the pressure adjustment means.

[0093] The pressing conditions may be, for example, a temperature of room temperature to 50° C. or less, and the atmosphere may be air or nitrogen. For the purpose of reducing voids, the metal particle film may be pressed onto the silicon substrate after a reduced pressure atmosphere of −0.01 MPa or less, preferably −0.05 MPa or less is created. The pressure of the pressing tool when pressing the metal particle film onto the silicon substrate may be within a range that does not crack the silicon wafer, and may be, for example, 0.01 MPa or more, 0.1 MPa or more, or 1 MPa or more.

[0094] It is preferable to press the metal particle film under conditions such that the concentration of metal particles in the filled metal particle composition 3 is 94 mass % or more.

[0095] Thereafter, as shown in FIG. 3(c), the support film 71 is peeled off.

[0096] In this embodiment, the surface of the metal particle composition 3 attached to the main surface of the silicon substrate 40 may be smoothed, or at least a portion of the metal particle composition 3 attached to the main surface of the silicon substrate 40 may be removed. In addition, the metal particle composition that passes through the through holes and protrudes to the side of the silicon substrate 40 opposite to the side where the metal particle film is pressed may be removed, or the protruding metal particle composition may be smoothed.

[0097] Furthermore, if necessary, a metal paste having the same composition as the above-mentioned metal paste may be applied to the side of silicon substrate 40 opposite to the side where the metal particle film is pressed, and then dried to provide layers of the metal particle composition on both main surfaces of silicon substrate 40. In this case as well, it is preferable that the concentration of metal particles in the layer of the metal particle composition is 94 mass % or more.

[0098] The metal particle composition 3 may be appropriately dried from the viewpoint of preventing the metal particles from flowing during sintering of the metal particle composition 3 and preventing the occurrence of voids in the metal sintered body contained in the metal body. When the metal particle composition 3 is dried, the atmosphere during drying may be an oxygen-free atmosphere such as nitrogen and a rare gas, or a reducing atmosphere such as hydrogen and formic acid.

[0099] The drying method may be drying by leaving at room temperature, drying by heating, or drying under reduced pressure. For example, a hot plate, a hot air dryer, a hot air heating furnace, a nitrogen dryer, an infrared ray dryer, an infrared heating furnace, a far-infrared heating furnace, a microwave heating device, a laser heating device, an electromagnetic heating device, a heater heating device, a steam heating furnace, a hot plate press device, etc. can be used for drying by heating or drying under reduced pressure. The temperature and time of drying may be appropriately adjusted according to the type and amount of the dispersion medium used. The temperature of drying may be, for example, 50°C or higher and 180°C or lower. The time of drying may be, for example, 1 minute or more and 120 minutes or less.

[0100] <Sintering process> After the filling step, the metal particle composition 3 is fired to sinter the metal particles contained in the metal particle composition 3. Hereinafter, a case will be described in which the metal particle-containing layer uses a metal particle film containing copper particles and solder particles.

[0101] In this case, as shown in (c1) of FIG. 4, a metal body-filled silicon substrate 50 is obtained, which includes a copper sintered body having a porous structure and solder, and in which a metal body 5 having voids (porosity) 4 fills the through-holes 30. FIG. 4 (c1) shows a metal body-filled silicon substrate 50 in which a metal body 5 is also provided on both main surfaces of a silicon substrate 40. FIG. 4 (c2) is a schematic diagram showing the configuration of a metal body formed using the above-mentioned metal particle film. The metal body includes a copper sintered body 12 having a porous structure, solder 14 scattered in the copper sintered body 12, and voids 4. The metal body can include, as the voids 4, the pores of the copper sintered body 12, voids present inside the solder 14, and voids present between the copper sintered body 12 and the solder 14.

[0102] When the metal particle-containing layer uses a metal particle film containing copper particles, a copper sintered body-filled silicon substrate can be obtained in which the through-holes are filled with a copper sintered body having a porous structure.

[0103] The calcination can be carried out by a heating treatment, for example, using a heating means such as a hot plate, a hot air dryer, a hot air heating furnace, a nitrogen dryer, an infrared dryer, an infrared heating furnace, a far-infrared heating furnace, a microwave heating device, a laser heating device, an electromagnetic heating device, a heater heating device, or a steam heating furnace.

[0104] The atmosphere during firing may be an oxygen-free atmosphere from the viewpoint of suppressing oxidation of the copper sintered body, or a reducing atmosphere from the viewpoint of removing the surface oxide of the copper particles in the metal particle composition 3. Examples of the oxygen-free atmosphere include the introduction of an oxygen-free gas such as nitrogen or a rare gas, or under vacuum. Examples of the reducing atmosphere include pure hydrogen gas, a mixed gas of hydrogen and nitrogen represented by forming gas, nitrogen containing formic acid gas, a mixed gas of hydrogen and a rare gas, and a rare gas containing formic acid gas. When the metal particle composition 3 is sintered by heating without pressurization, it is preferably in pure hydrogen gas or a mixed gas of hydrogen and nitrogen represented by forming gas, and preferably in pure hydrogen gas. By heating in pure hydrogen gas, it is possible to lower the sintering temperature of the copper particles. When pure hydrogen gas is used, even if the thickness of the substrate is as thick as 600 μm and the diameter of the through hole 30 is as small as 10 μm, the gas reaches the center of the through hole 30, making it easy to obtain the metal body 5 containing the copper sintered body.

[0105] The maximum temperature reached during the heat treatment may be 150°C or higher, and may be 350°C or lower, 300°C or lower, or 260°C or lower, from the viewpoint of reducing thermal damage to each component and improving yield. If the maximum temperature reached is 150°C or higher, sintering tends to proceed sufficiently when the maximum temperature reached is held for 60 minutes or less. From the viewpoint of volatilizing all the dispersion medium and improving yield, the maximum temperature reached may be held for 1 minute or more, and may be 60 minutes or less, 40 minutes or less, or 30 minutes or less.

[0106] The metal particle composition may be fired under pressure. In this case, the pressure may be 0.05 MPa or more, 0.1 MPa or more, or 0.3 MPa or more in an atmosphere containing pure hydrogen gas, and 20 MPa or less, 15 MPa or less, or 10 MPa or less. In addition, the pressure may be 1 MPa or more, or 3 MPa or more, and 20 MPa or less, 15 MPa or less, or 10 MPa or less in an atmosphere containing nitrogen gas.

[0107] The pressure is set to 0.05 MPa or more when pure hydrogen gas is used, and 1 MPa or more when nitrogen gas is used, which makes it easier to suppress the generation of voids in the metal body 5 formed in the center of the through hole 30, and makes it easier to obtain a metal body with good conductivity. In addition, by setting the pressure to the above-mentioned lower limit value or more, when the silicon substrate 40 has a metal coating 2, it is easier to improve the bonding strength between the metal coating 2 and the metal body 5. Furthermore, the silicon substrate 40 after being filled with the metal particle composition may be pressed by sandwiching it from above and below using a pressure jig A similar to that shown in (b) of FIG. 3. In this case, by setting the pressure applied to the pressure jig A to the above-mentioned lower limit value or more, it is easier to smooth the surface of the metal body formed on the main surface of the silicon substrate 40. If the surface of the metal body is smooth, there is an advantage that fine wiring is easily formed when wiring is formed by etching or the like in a later process.

[0108] If the pressure is 20 MPa or less, warping of the silicon substrate 40 is easily suppressed. The inventors speculate that the reason for obtaining such an effect is as follows. First, when the pressure is increased, the sintered density of the copper particles contained in the metal particle composition (particularly the density of the side in contact with the pressing jig A) increases, and the thermal expansion coefficient of the formed copper sintered body is considered to approach the thermal expansion coefficient of general copper at 25°C, 16.5 μm / (m·K). On the other hand, the thermal expansion coefficient of silicon at 25°C is 2.6 μm / (m·K). Therefore, as the density of the copper sintered body increases, the difference in the thermal expansion coefficient between the copper sintered body and silicon increases, and warping is likely to occur. In this embodiment, it is considered that the pressure is set to 20 MPa or less, and as a result of the increase in the density of the copper sintered body being appropriately suppressed, the difference in the thermal expansion coefficient between the copper sintered body and silicon becomes smaller, and warping is suppressed.

[0109] In addition, if the pressure applied during firing is within the above range, a special pressure device is not required, and the yield is not compromised, and voids can be reduced and the bonding strength and connection reliability can be further improved. Examples of methods for applying pressure to a silicon substrate filled with a metal particle composition include a method of placing a weight on the substrate, a method of applying pressure using a pressure device, and a method of applying pressure using a fixed jig for applying pressure.

[0110] From the viewpoint of reducing the volume resistivity of the metal body, the porosity (proportion of voids contained in the metal body) of the metal body formed on the main surface of the silicon substrate may be 15 volume % or less, 14 volume % or less, 12 volume % or less, or 9 volume % or less based on the total volume (including voids) of the metal body. Moreover, from the viewpoint of suppressing cracking and warping of the silicon substrate 40, the porosity of the metal body 5 may be 1 volume % or more, 3 volume % or more, or 5 volume % or more.

[0111] By having the metal body formed on the main surface of the silicon substrate have the above-mentioned porous structure, it is possible to lower the thermal expansion coefficient, reduce the difference in thermal expansion coefficient with the silicon wafer, and suppress cracking and warping of the silicon substrate.

[0112] From the viewpoint of reducing the volume resistivity of the metal body, the porosity of the metal body filled in the through holes (the proportion of voids contained in the metal body) may be 15 volume % or less, 14 volume % or less, 12 volume % or less, or 9 volume % or less based on the total volume (including voids) of the metal body. Moreover, from the viewpoint of mitigating the stress applied to the copper sintered body and suppressing cracking and warping of the silicon substrate, the porosity of the metal body 5 may be 1 volume % or more, 3 volume % or more, or 5 volume % or more.

[0113] When the metal body filled in the through holes has the above-mentioned porous structure, the stress applied to the metal body can be alleviated, and cracks and warping of the silicon substrate can be suppressed.

[0114] The porosity of the metal body is calculated by the following procedure. (i) A cross section of a metal body of a metal body-filled silicon substrate (a cut surface in the thickness direction of the substrate) is exposed by a focused ion beam. (ii) A cross-sectional image of the exposed cross section (within a range of 10 μm in the thickness direction of the substrate and a range of 10 μm in the direction perpendicular to the thickness direction of the substrate) is taken using a scanning electron microscope. (iii) The cross-sectional image obtained is binarized so that the metal portion and the porous portion are separated. (iv) From the binarized cross-sectional image, the ratio of the area of ​​the porous portion to the total area of ​​the cross-section of the metal body is determined as the porosity of the metal body. When calculating the porosity of the metal body filled in the through-hole, in the above (i), a cross section of the central part of the metal body filled in the through-hole is exposed. When calculating the porosity of the central part of the metal body filled in the through-hole, a range of ±5 μm in the thickness direction of the substrate and ±5 μm in the direction perpendicular to the thickness direction of the substrate is observed from the central part of the metal body filled in the through-hole. When calculating the porosity of the metal body formed on the main surface of the metal body-filled silicon substrate, in the above (i), a cross section of the metal body on the main surface is exposed. When calculating the porosity of the metal body formed on the main surface of the metal body-filled silicon substrate, a region up to 5 μm from the surface of the metal body formed on the main surface is observed. When calculating the porosity of the metal body used to calculate the filling rate of the cured resin in the conductor described below, the observation points of the metal body can be appropriately set to be the same as the observation points of the conductor.

[0115] In addition, if the pressure applied during firing is within the above range, a special pressure device is not required, and the yield is not compromised, and voids can be reduced and the bonding strength and connection reliability can be further improved. Examples of methods for applying pressure to a silicon substrate filled with a metal particle composition include a method of placing a weight on the substrate, a method of applying pressure using a pressure device, and a method of applying pressure using a fixing jig for applying pressure.

[0116] The copper sintered body contained in the metal body may have a copper element ratio of 95 mass% or more, 97 mass% or more, 98 mass% or more, or 100 mass% among the constituent elements excluding light elements. If the copper element ratio in the copper sintered body is within the above range, the formation of intermetallic compounds or the precipitation of different elements at the metallic copper crystal boundaries can be suppressed, the properties of the metallic copper constituting the copper sintered body are likely to be strong, and even better connection reliability is likely to be obtained.

[0117] The content of solder contained in the metal body may be 3 parts by mass or more, 10 parts by mass or more, or 10 parts by mass or more, relative to 100 parts by mass of the copper sintered body contained in the metal body, from the viewpoint of suppressing cracks in the metal body, and may be 20 parts by mass or less, 15 parts by mass or less, or 10 parts by mass or less, from the viewpoint of reducing the volume resistivity of the metal body.

[0118] In the metal body forming step, the metal particle composition may be heated and fired without applying pressure. In this case, the porosity of the metal body formed on the main surface of the silicon substrate tends to be large, and the thermal expansion coefficient of the metal body is reduced, making it difficult for the silicon substrate to crack or warp.

[0119] <Resin impregnation process> In this step, for example, the metal body 5 can be impregnated with the curable resin composition by applying the curable resin composition to the metal body-filled silicon substrate 50 obtained through the metal body formation step. In this embodiment, the metal body 5 filling the through hole 30 and the metal body 5 formed on both main surfaces of the silicon substrate 40 are impregnated with the curable resin composition. It is preferable that the pores 4 of the metal body 5 are sufficiently filled with the impregnated curable resin composition.

[0120] (Curable resin composition) The components constituting the curable resin composition include a thermosetting compound. Examples of the thermosetting compound include an oxetane compound, an epoxy compound, an episulfide compound, a (meth)acrylic compound, a phenol compound, an amino compound, an unsaturated polyester compound, a polyurethane compound, a silicone compound, and a polyimide compound. Among them, an epoxy compound may be used in order to further improve the curability and viscosity of the curable resin composition and improve the characteristics and insulation reliability when left at high temperatures.

[0121] The curable resin composition may further include a heat curing agent. Examples of the heat curing agent include imidazole curing agent, amine curing agent, phenol curing agent, polythiol curing agent, acid anhydride, thermal cationic initiator, and thermal radical generator. These may be used alone or in combination of two or more. Among these, imidazole curing agent, polythiol curing agent, or amine curing agent are preferred in that they can be cured quickly at low temperatures. In addition, a latent curing agent is preferred in that the storage stability is increased when the heat curing compound and the heat curing agent are mixed. The latent curing agent is preferably a latent imidazole curing agent, a latent polythiol curing agent, or a latent amine curing agent. The heat curing agent may be coated with a polymeric substance such as a polyurethane resin or a polyester resin.

[0122] The imidazole curing agent is not particularly limited, and examples thereof include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, and 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct.

[0123] The polythiol curing agent is not particularly limited, and examples thereof include trimethylolpropane tris-3-mercaptopropionate, pentaerythritol tetrakis-3-mercaptopropionate, and dipentaerythritol hexa-3-mercaptopropionate. The solubility parameter of the polythiol curing agent is preferably 9.5 or more, and preferably 12 or less. The solubility parameter is calculated by the Fedors method. For example, the solubility parameter of trimethylolpropane tris-3-mercaptopropionate is 9.6, and the solubility parameter of dipentaerythritol hexa-3-mercaptopropionate is 11.4.

[0124] The amine curing agent is not particularly limited, and examples thereof include hexamethylenediamine, octamethylenediamine, decamethylenediamine, 3,9-bis(3-aminopropyl)-2,4,8,10-tetraspiro[5.5]undecane, bis(4-aminocyclohexyl)methane, metaphenylenediamine, and diaminodiphenylsulfone.

[0125] The above-mentioned thermal cationic curing agent includes an iodonium cationic curing agent, an oxonium cationic curing agent, and a sulfonium cationic curing agent. The above-mentioned iodonium cationic curing agent includes bis(4-tert-butylphenyl)iodonium hexafluorophosphate. The above-mentioned oxonium cationic curing agent includes trimethyloxonium tetrafluoroborate. The above-mentioned sulfonium cationic curing agent includes tri-p-tolylsulfonium hexafluorophosphate.

[0126] The thermal radical generator is not particularly limited, and examples thereof include azo compounds and organic peroxides. Examples of the azo compounds include azobisisobutyronitrile (AIBN). Examples of the organic peroxides include di-tert-butyl peroxide and methyl ethyl ketone peroxide.

[0127] Examples of the method for applying the curable resin composition include screen printing, transfer printing, offset printing, jet printing, and application methods using a dispenser, jet dispenser, needle dispenser, comma coater, slit coater, die coater, gravure coater, slit coat, letterpress printing, intaglio printing, gravure printing, stencil printing, soft lithography, bar coating, applicator, particle deposition method, spray coater, spin coater, dip coater, and the like.

[0128] The curable resin composition may be applied to one of the main surfaces of the metal body-filled silicon substrate 50, or may be applied to a part of the main surface. When applying the resin composition to both sides of the metal body-filled silicon substrate 50, the resin composition may be applied to one of the main surfaces of the metal body-filled silicon substrate 50, the resin composition may be allowed to penetrate to the main surface side of the metal body-filled silicon substrate 50 to which the resin composition has not been applied, and then the resin composition may be applied to the main surface to which the resin composition has not been applied. This allows the resin composition to permeate the holes 4.

[0129] By leaving the metal body-filled silicon substrate 50 coated with the curable resin composition in a reduced pressure environment, the impregnation of the curable resin composition into the pores 4 of the metal bodies 5 can be improved.

[0130] In the resin impregnation step, it is preferable to impregnate the metal body with the cured resin composition so that the filling rate of the cured resin in the conductor formed through the resin curing step falls within a preferred range described below.

[0131] <Resin curing process> In this step, as shown in (d1) of FIG. 5, the curable resin composition impregnated in the metal body 5 (the curable resin composition filled in the pores 4) is cured to form a conductor 35 including the metal body 5 in which the pores 4 are filled with the resin cured material 6, and a substrate 51 having a silicon through-hole electrode in which a silicon through-hole electrode is provided in the through-hole 30 can be obtained. In the case of this embodiment, the conductor 35 including the metal body 5 in which the pores 4 are filled with the resin cured material 6 is also provided on both main surfaces of the silicon substrate 40. (d2) of FIG. 5 is a schematic diagram showing the configuration of the conductor. The conductor includes a copper sintered body 12, a solder 14, and a resin cured material 6 filled in the pores. The solder 14 may be scattered in the conductor 35. The resin cured material 6 may be present in the pores of the copper sintered body 12, in the voids present inside the solder 14, or in the voids present between the copper sintered body 12 and the solder 14.

[0132] When the metal particle-containing layer uses a metal particle film containing copper particles, a conductor containing a copper sintered body having pores filled with a cured resin is formed, and a substrate having a silicon through electrode in which a silicon through electrode is provided in a through hole can be obtained. In this case, a conductor containing a copper sintered body having pores filled with a cured resin can be provided on both main surfaces of the silicon substrate.

[0133] The curable resin composition can be cured by a heat treatment, which can be performed using a heating means such as a hot plate, a hot air dryer, a hot air heating furnace, a nitrogen dryer, an infrared dryer, an infrared heating furnace, a far-infrared heating furnace, a microwave heating device, a laser heating device, an electromagnetic heating device, a heater heating device, or a steam heating furnace.

[0134] The atmosphere in the resin curing step may be an oxygen-free atmosphere from the viewpoint of suppressing oxidation of the metal body 5 (particularly the copper sintered body), or may be a reducing atmosphere from the viewpoint of removing surface oxides of the metal body 5 (particularly the copper sintered body). Examples of the oxygen-free atmosphere include an oxygen-free gas such as nitrogen or a rare gas, or a vacuum. Examples of the reducing atmosphere include a pure hydrogen gas atmosphere, a mixed gas of hydrogen and nitrogen such as forming gas, nitrogen containing formic acid gas, a mixed gas of hydrogen and a rare gas, and a rare gas containing formic acid gas.

[0135] From the viewpoint of reducing thermal damage to each component and improving yield, the maximum temperature reached during the heat treatment in the resin curing step may be 150° C. or higher, and may be 350° C. or lower, 300° C. or lower, or 260° C. or lower. If the maximum temperature reached is 150° C. or higher, curing of the resin composition tends to proceed sufficiently when the maximum temperature is held for 60 minutes or less.

[0136] The conductor 35 formed in the resin curing step (the conductor before the conductor removing step) may have a content (filling rate) of the cured resin 6 that satisfies the following condition.

[0137] (Through hole conductor) (a) In the region from point S1 where line L1 passing through center C of through hole 30 (center of hole length and center of hole diameter there) and extending in the thickness direction of the substrate intersects with the surface of conductor 35 to a depth of 10 μm (see (d1) in Figure 5), the filling rate of the cured resin may be 80 volume % or more, 90 volume % or more, or 95 volume % or more, based on the total volume of the internal space of the pores (voids) of the metal body. (b) In the region from point S1 to a depth of 10 to 20 μm, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. (c) In the region from point S1 to a depth of 20 to 30 μm, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. (d) Within a range of ±5 μm from the center C of the through hole 30 in the thickness direction of the substrate and in a direction perpendicular to the thickness direction of the substrate, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body.

[0138] (Conductors on the main surface of the substrate) (e) In the region from the surface S2 of the conductor 35 formed on the main surface of the substrate to a depth of 5 μm (see (d1) in FIG. 5), the filling rate of the cured resin may be 80 volume % or more, 90 volume % or more, or 95 volume % or more, based on the total volume of the porous internal space of the metal body. (f) In the region from the surface S2 of the conductor 35 formed on the main surface of the substrate to a depth of 10 μm, the filling rate of the cured resin may be 80 volume % or more, 90 volume % or more, or 95 volume % or more, based on the total volume of the porous internal space of the metal body. (g) In the region 10 to 20 μm deep from the surface S2, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. (h) In the region 20 to 30 μm deep from the surface S2, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body.

[0139] The filling rate of the cured resin 6 in the conductor 35 is calculated by the following procedure. (i) A cross section of the conductor of a conductor-filled silicon substrate (a cut surface in the thickness direction of the substrate) is exposed by a focused ion beam. (ii) A cross-sectional image of the exposed cross section (within a range of 10 μm in the thickness direction of the substrate and a range of 10 μm in the direction perpendicular to the thickness direction of the substrate) is taken using a scanning electron microscope. (iii) The cross-sectional image obtained is binarized so that the metal and cured resin portions are separated from the porous portions not filled with the cured resin. (iv) From the binarized cross-sectional image, the ratio of the area of ​​the porous portion not filled with the cured resin to the total area of ​​the cross-section of the conductor is calculated, and this is regarded as the porosity of the conductor. (v) The filling rate of the cured resin in the conductor is calculated by substituting the porosity of the metal body before impregnation with the curable resin composition and the porosity of the conductor into the following formula (1). Filling rate of cured resin in conductor (%) = [(B A) / B] × 100 Equation (1) [In formula (1), A represents the porosity (%) of the conductor, and B represents the porosity (%) of the metal body.] When calculating the porosity of the conductor filled in the through-hole, a cross section of the central part of the conductor in the through-hole is exposed in the above (i).When calculating the porosity of the conductor formed on the main surface of the conductor-filled silicon substrate, a cross section of the conductor on the main surface is exposed in the above (i).

[0140] <Conductor removal process> In this step, it is possible to remove at least a part of the conductor 35 formed on the main surface of the silicon substrate 40. Means for removing the conductor include chemical polishing, mechanical polishing, chemical mechanical polishing, fly-cut processing, plasma processing, etc. Fly-cut processing refers to cutting and flattening with a surface planer.

[0141] In this embodiment, from the viewpoint of being easily applicable by a general method, the removal means is preferably one or more selected from the group consisting of etching, mechanical polishing, and chemical mechanical polishing.

[0142] The manufacturing method of the silicon substrate having the silicon through electrode of this embodiment includes a conductor removal process, so that, for example, the surface of the conductor 35 formed on the main surface of the silicon substrate 40 becomes flat, making it easier to form wiring.

[0143] In this embodiment, the filling rate of the cured resin 6 in the conductor 35 after the conductor removing step may satisfy the following condition. The filling rate can be calculated in the same manner as above.

[0144] (Through hole conductor) (a) In the region from point S3 where line L1 passing through center C of through hole 30 (center of hole length and center of hole diameter D there) and extending in the thickness direction of the substrate intersects with the surface of conductor 35 to a depth of 10 μm (see (e) of Figure 6), the filling rate of the cured resin may be 80 volume % or more, 90 volume % or more, or 95 volume % or more, based on the total volume of the internal space of the porous (void) parts of the metal body. (b) In the region from point S3 to a depth of 10 to 20 μm, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. (c) In the region from point S3 to a depth of 20 to 30 μm, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. (d) Within a range of ±5 μm from the center C of the through hole 30 in the thickness direction of the substrate and in a direction perpendicular to the thickness direction of the substrate, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body.

[0145] (Conductors on the main surface of the substrate) (e) In the region from the surface S4 of the conductor 35 formed on the main surface of the substrate to a depth of 5 μm (see (e) of Figure 6), the filling rate of the cured resin may be 80 volume % or more, 90 volume % or more, or 95 volume % or more, based on the total volume of the internal space of the porous (void) parts of the metal body. (f) In the region from the surface S4 of the conductor 35 formed on the main surface of the substrate to a depth of 10 μm, the filling rate of the cured resin may be 80 volume % or more, 90 volume % or more, or 95 volume % or more, based on the total volume of the porous internal space of the metal body. (g) In the region 10 to 20 μm deep from the surface S4, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. (h) In the region 20 to 30 μm deep from the surface S4, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body.

[0146] From the viewpoint of increasing the density of the resulting semiconductor device, the ratio L / D of the length L of the through silicon electrode to the hole diameter D may be 1 or more, 5 or more, or 10 or more, and may be 15 or less, 10 or less, or 5 or less. The length L of the through silicon electrode may be the thickness of a substrate having the through silicon electrode. In this case, the ratio T / D of the thickness T of the substrate having the through silicon electrode to the hole diameter D of the through silicon electrode may be in the above range.

[0147] In the method for manufacturing a substrate having a through electrode of this embodiment, the conductor is filled with a cured resin, but the above-mentioned resin impregnation step and resin curing step may be omitted and the through electrode may be formed from a metal body.

[0148] The method for manufacturing a substrate having a through electrode according to the present embodiment may further include a wiring forming step, which may include a resist forming step, an etching step, and a resist removing step, which will be described below.

[0149] <Resist formation process> In the resist formation step, an etching resist 8 is formed on the conductor 35 formed on the main surface of the silicon substrate 40, as shown in FIG. 6(f).

[0150] Examples of methods for forming the etching resist 8 include a method of silk screen printing a resist ink, or a method of laminating a negative photosensitive dry film for etching resist onto a copper foil, placing a light-transmitting photomask on top of it in the shape of the wiring, exposing it to ultraviolet light, and removing the unexposed areas with a developer.

[0151] <Etching process> In the etching step, as shown in (g) of Fig. 7, the conductor 35 in the portion not covered with the etching resist 8 is removed by etching. In this embodiment, a part of the metal coating 2 provided on each main surface of the silicon wafer 1 is removed by etching.

[0152] Examples of the etching method include a method using a chemical etching solution typically used for wiring boards, such as a solution of cupric chloride and hydrochloric acid, a ferric chloride solution, a solution of sulfuric acid and hydrogen peroxide, or an ammonium persulfate solution.

[0153] <Resist removal process> In the resist removal step, the etching resist 8 formed on the conductor 35 is removed.

[0154] The method for manufacturing a base body having a through electrode according to this embodiment further includes a wiring formation step having the above steps, whereby wiring 9 including conductor 35 can be formed on the main surface of silicon substrate 40.

[0155] (Base having through electrodes according to the first embodiment) FIG. 7(h) is a cross-sectional view showing one embodiment of a substrate having a silicon through-hole that can be manufactured by the method according to the first embodiment described above. The substrate 52 having a silicon through-hole shown in FIG. 7(h) includes a silicon wafer 1 having through-holes 30, and includes a silicon substrate having through-holes 30 on both main surfaces, and a conductor filling the through-holes 30. The conductor 35 includes a copper sintered body having a porous structure and solder scattered in the copper sintered body, and includes a metal body 5 having voids 4, and the metal body 5 includes, as the voids 4, voids present inside the solder and / or voids present between the solder and the copper sintered body. The conductor 35 further includes a resin cured material 6 filling the voids 4.

[0156] 7(h), the substrate 52 having the silicon through electrode has the metal coating 2 provided on both main surfaces of the silicon wafer 1 and on the wall surface of the through hole, but the metal coating 2 does not have to be provided on the main surfaces, it may be provided only on one of the main surfaces, or it may not have to be provided on the wall surface of the through hole. Also, the substrate 52 having the silicon through electrode has the wiring 9 including the metal coating 2 and the conductor 35 provided on both main surfaces of the silicon substrate 40, but the wiring 9 may be provided on one of the main surfaces of the silicon substrate 40.

[0157] In addition, when the metal particle-containing layer uses a metal particle film containing copper particles, the substrate having the silicon through electrode includes a silicon wafer having through holes, the silicon substrate having through holes communicating with both main surfaces, and a conductor filling the through holes, and the conductor can include a copper sintered body having a porous structure and a resin cured product filled in the pores of the copper sintered body. In this case, the substrate having the silicon through electrode may have a metal coating on both main surfaces of the silicon wafer and on the wall surface of the through hole. In addition, the metal coating may not be provided on the main surface, may be provided only on one main surface, and may not be provided on the wall surface of the through hole. In addition, the substrate having the silicon through electrode may have wiring including a metal coating and a conductor on both main surfaces of the silicon substrate. The wiring may be provided on one main surface of the silicon substrate.

[0158] Substrate 52 having a silicon through electrode may be one in which the filling rate of cured resin 6 in the conductor satisfies the following condition: The filling rate can be calculated in the same manner as above.

[0159] (Through hole conductor) (a) In the region from point S5, which passes through center C of through hole 30 (center of hole length and center of hole diameter there) and where line L1 extending in the thickness direction of the substrate intersects with the surface of the conductor, to a depth of 10 μm (see (h) of Figure 7), the filling rate of the cured resin may be 80 volume % or more, 90 volume % or more, or 95 volume % or more, based on the total volume of the internal space of the pores (voids) of the metal body. (b) In the region from point S5 to a depth of 10 to 20 μm, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. (c) In the region from point S5 to a depth of 20 to 30 μm, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal spaces of the metal body. (d) Within a range of ±5 μm from the center C of the through hole 30 in the thickness direction of the substrate and in a direction perpendicular to the thickness direction of the substrate, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body.

[0160] (Conductors on the main surface of the substrate) (e) In a region from the surface S6 of the conductor formed on the main surface of the substrate to a depth of 5 μm (see (h) of FIG. 7), the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. (f) In the region from the surface S6 of the conductor 35 formed on the main surface of the substrate to a depth of 10 μm, the filling rate of the cured resin may be 80 volume % or more, 90 volume % or more, or 95 volume % or more, based on the total volume of the porous internal space of the metal body. (g) In the region 10 to 20 μm deep from the surface S6, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. (h) In the region 20 to 30 μm deep from the surface S6, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body.

[0161] (Semiconductor Device According to the First Embodiment) A semiconductor device manufactured using a base having a through electrode (substrate having a silicon through electrode) according to the first embodiment will be specifically described with reference to FIG. 8. FIG. 8 is a schematic cross-sectional view showing one embodiment of a semiconductor device. In the semiconductor device 100 shown in FIG. 8(a), the wiring 27 on the interposer substrate 25 is directly connected to the conductor 35 of the substrate 52 having the silicon through electrode, so that the interposer substrate 25 and the substrate 52 having the silicon through electrode are flip-chip connected. The gap between the interposer substrate 25 and the substrate 52 having the silicon through electrode is filled with a cured product 20 of the adhesive without any gaps, and is sealed. On the main surface of the substrate 52 having the silicon through electrode on the opposite side to the interposer substrate 25, the substrates 52 having the silicon through electrode are repeatedly stacked. The substrates 52 having the silicon through electrode are connected to each other by the conductor 35. The gap between the substrates 52 having the silicon through electrode is filled with a cured product 20 of the adhesive without any gaps, and is sealed.

[0162] The semiconductor device 100 may be obtained by, for example, the following method. That is, substrates 52 having silicon through-hole electrodes are laminated via an adhesive to obtain a laminate. The adhesive may be cured at the time of lamination. The obtained laminate and the interposer substrate 25 are electrically connected by pressure bonding, and a connection body in which the laminate and the interposer substrate 25 are electrically connected is formed. A dicing tape is attached to the surface of the formed connection body opposite to the surface on which the interposer substrate 25 is provided, and dicing is performed along the dicing lines to obtain the semiconductor device 100.

[0163] In the semiconductor device 200 shown in FIG. 8(b), the wiring 27 on the interposer substrate 25 and the conductor 35 of the substrate 52 having the silicon through electrode are connected via the fine bumps 15, so that the interposer substrate 25 and the substrate 52 having the silicon through electrode are flip-chip connected. The gap between the interposer substrate 25 and the substrate 52 having the silicon through electrode is filled with the cured product 20 of the adhesive without any gaps, and is sealed. On the main surface of the substrate 52 having the silicon through electrode on the opposite side to the interposer substrate 25, the substrates 52 having the silicon through electrode are repeatedly stacked via the fine bumps 15. The gap between the substrates 52 having the silicon through electrode is filled with the cured product 20 of the adhesive without any gaps, and is sealed.

[0164] The semiconductor device 200 may be obtained by, for example, the following method. That is, a substrate 52 having a silicon through electrode with fine bumps 15 provided on one main surface is laminated via an adhesive to obtain a laminate. The adhesive may be cured at the time of lamination. The obtained laminate and the interposer substrate 25 are electrically connected by pressure bonding, and a connection body in which the laminate and the interposer substrate 25 are electrically connected is formed. A dicing tape is attached to the surface of the formed connection body opposite to the surface on which the interposer substrate 25 is provided, and dicing is performed along the dicing lines to obtain the semiconductor device 200.

[0165] (Method for manufacturing a substrate having a through electrode according to a second embodiment) 9 and 10 are schematic diagrams showing a method for manufacturing a substrate having a silicon through electrode, as a method for manufacturing a base body having a through electrode according to the second embodiment.

[0166] The method for producing a substrate having a through electrode according to the second embodiment includes a preparation step of preparing a substrate having an insulating substrate with non-through holes and one of the main surfaces on which the non-through holes are opened, a conductor forming step of forming a conductor in the non-through holes, and a grinding step of providing a through electrode by grinding the surface opposite to the surface on which the non-through holes of the substrate on which the conductor is formed are opened, the conductor forming step includes a metal body forming step of forming a metal body having pores so as to fill at least the non-through holes, and the metal body forming step includes a filling step of pressing the metal particle film of this embodiment against the substrate so that the metal particle-containing layer of the metal particle film contacts the substrate, filling the non-through holes of the substrate with a metal particle composition, and a firing step of firing the metal particle composition to form a metal body. In the method of this embodiment, the conductor forming step further includes a resin impregnation step of impregnating the metal body with a curable resin composition, and a resin curing step of curing the curable resin composition impregnated in the metal body.

[0167] As with the method of the first embodiment, the method of the second embodiment will be described taking as an example a case in which a silicon substrate having an insulating substrate of a silicon wafer is prepared as a substrate, and a substrate having a silicon through-hole electrode is manufactured as a substrate having a through-hole electrode, as an example; however, the silicon wafer can be replaced with another insulating substrate in the following description.

[0168] <Substrate preparation process> 9(a), a silicon substrate 41 can be prepared, which has a silicon wafer 1 with non-through holes 31 formed therein, and a metal coating 2 formed on the wall and bottom surfaces of the non-through holes 31 and on the surface of the silicon wafer 1. The non-through holes 31 open on one main surface of the silicon wafer 1.

[0169] From the viewpoint of suppressing warpage of the substrate after sintering, the thickness of the silicon wafer 1 may be 20 μm or more, 30 μm or more, or 50 μm or more, and may be 500 μm or less, 400 μm or less, or 300 μm or less.

[0170] The upper limit of the hole diameter of the non-through holes 31 may be 200 μm or less, 100 μm or less, or 60 μm or less from the viewpoint of increasing the density of the obtained semiconductor device, and the lower limit of the hole diameter of the non-through holes 31 is not particularly limited, but may be 10 μm or more, 20 μm or more, or 30 μm or more.

[0171] The hole length (hole depth) of non-through hole 31 can be set appropriately according to the length of the silicon through electrode to be formed.

[0172] The metal coating 2 may be provided on the surface of the silicon wafer 1 where the non-through holes 31 are open and on the wall surfaces and bottom surfaces of the non-through holes 31, or may or may not be provided on the wall surfaces and bottom surfaces of the non-through holes 31. In the embodiment shown in (a) of Figure 9, a silicon substrate 41 is provided with the metal coating 2 on the surface of the silicon wafer 1 where the non-through holes 31 are open and on the wall surfaces and bottom surfaces of the non-through holes 31.

[0173] The metal coating 2 can be made of the same material as in the first embodiment.

[0174] <Metal body formation process> The metal body forming step may include the following filling step and firing step.

[0175] <Filling process> In this step, the metal particle film 70 of the above-described embodiment is pressed against the silicon substrate 41 so that the metal particle-containing layer 72 of the metal particle film is in contact with the silicon substrate 40, and the metal particle composition 3 is filled into the non-through holes 31 of the silicon substrate 41. When the metal particle-containing layer contains copper particles, or copper particles and solder particles, the metal particle composition containing copper particles, or copper particles and solder particles, is filled.

[0176] 9(a) and 9(b), the filling step can be performed by sandwiching and pressurizing the metal particle film 70 and the silicon substrate 41 from above and below with a pressing jig A. The pressing jig A can be the same as that described above.

[0177] The pressing conditions may be, for example, a temperature of room temperature to 50° C. or less, and the atmosphere may be air or nitrogen. For the purpose of reducing voids, the metal particle film may be pressed onto the silicon substrate after a reduced pressure atmosphere of −0.01 MPa or less, preferably −0.05 MPa or less is created. The pressure of the pressing tool when pressing the metal particle film onto the silicon substrate may be within a range that does not crack the silicon wafer, and may be, for example, 0.01 MPa or more, 0.1 MPa or more, or 1 MPa or more.

[0178] It is preferable to press the metal particle film under conditions such that the concentration of metal particles in the filled metal particle composition 3 is 94 mass % or more.

[0179] Thereafter, as shown in FIG. 9(c), the support film 71 is peeled off.

[0180] In this embodiment, the surface of the metal particle composition 3 adhering to the main surface of the silicon substrate 41 may be smoothed, or at least a portion of the metal particle composition 3 adhering to the main surface of the silicon substrate 41 may be removed.

[0181] The metal particle composition 3 may be appropriately dried in the same manner as in the first embodiment. When the metal particle composition 3 is dried, the atmosphere, method, and temperature during drying may be the same as in the first embodiment.

[0182] <Sintering process> After the filling step, the metal particle composition 3 is fired to sinter the copper particles contained in the metal particle composition 3. Hereinafter, a case will be described in which the metal particle-containing layer uses a metal particle film containing copper particles and solder particles.

[0183] 10(c), a metal body-filled silicon substrate 60 is obtained in which the non-through holes 31 are filled with metal bodies 5 including pores 4, i.e., having a porous structure. In this embodiment, a metal body-filled silicon substrate 60 is obtained in which the metal bodies 5 are provided also on the surface of the silicon substrate 41 where the non-through holes 31 are open.

[0184] When the metal particle-containing layer uses a metal particle film containing copper particles, a copper sintered body-filled silicon substrate can be obtained in which the non-penetrating pores are filled with a copper sintered body having a porous structure.

[0185] The firing conditions may be the same as those in the first embodiment.

[0186] The porosity of the metal body formed on the surface of the silicon substrate where the non-penetrating holes are open may be the same as the porosity of the metal body formed on the main surface of the silicon substrate in the first embodiment. The porosity of the metal body can be calculated by the same procedure as in the first embodiment.

[0187] The porosity of the metal body filled in the non-through holes may be similar to the porosity of the metal body filled in the through holes in the first embodiment.

[0188] The ratio of copper elements in the elements excluding light elements among the constituent elements of the copper sintered body contained in the metal body may be the same as that of the first embodiment. Also, the content of solder contained in the metal body may be the same as that of the first embodiment.

[0189] <Resin impregnation process> In this step, for example, the metal body 5 can be impregnated with the curable resin composition by applying the curable resin composition to the metal body-filled silicon substrate 60 obtained through the metal body formation step. In this embodiment, the metal body 5 filling the non-through holes 31 and the metal body 5 formed on the surface of the silicon substrate 41 where the non-through holes are open are impregnated with the curable resin composition. It is preferable that the voids 4 of the metal body 5 are sufficiently filled with the impregnated curable resin composition.

[0190] The curable resin composition may be the same as that in the first embodiment. The method for applying the curable resin composition may be the same as that in the first embodiment. The filling rate of the curable resin composition in the holes 4 of the metal body 5 may be appropriately changed according to the filling rate of the resin cured material 6 of the conductor 35 after the resin curing step.

[0191] <Resin curing process> In this step, the curable resin composition impregnated into the metal body 5 (the curable resin composition filled in the holes 4) is cured to form a conductor 35 including the metal body 5 with the holes 4 filled with the cured resin 6. In the case of this embodiment, the conductor 35 including the metal body 5 with the holes 4 filled with the cured resin 6 is also provided on the surface of the silicon substrate 41 where the non-through holes are open.

[0192] The curing conditions for the resin composition in the resin curing step may be the same as those in the first embodiment.

[0193] The conductor formed in the resin curing step (the conductor before the conductor removing step and the grinding step) may have a filling rate of the cured resin adjusted so that the filling rate of the cured resin in the silicon through electrode to be formed satisfies the condition described below. For example, the conductor may have a filling rate of the cured resin that satisfies the following condition:

[0194] (Blind hole conductor) (a) In the region up to a depth of 10 μm from the point where a line passing through the center of the non-penetrating hole (the center of the hole length and the center of the hole diameter there) and extending in the thickness direction of the substrate intersects with the surface of the conductor, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. (b) In a region 10 to 20 μm deep from the point where a line passing through the center of the non-penetrating hole and extending in the thickness direction of the substrate intersects with the surface of the conductor, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the internal space of the porous (void) parts of the metal body. (c) In a region 20 to 30 μm deep from the point where a line passing through the center of the non-penetrating hole and extending in the thickness direction of the substrate intersects with the surface of the conductor, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body.

[0195] (Conductors on the main surface of the substrate) (e) In a region from the surface of the conductor formed on the main surface of the substrate to a depth of 5 μm, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. (f) In a region from the surface of the conductor formed on the main surface of the substrate to a depth of 10 μm, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. (g) In a region 10 to 20 μm deep from the surface of the conductor formed on the main surface of the substrate, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. (h) In a region 20 to 30 μm deep from the surface of the conductor formed on the main surface of the substrate, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body.

[0196] The filling rate of the cured resin 6 in the conductor is calculated in the same manner as described in the method for manufacturing a substrate having a silicon through electrode according to the first embodiment.

[0197] <Conductor removal process> The method for manufacturing a substrate having a silicon through electrode of this embodiment may further include a conductor removing step after the resin curing step. In this step, at least a part of the conductor 35 formed on one main surface of the silicon substrate 41 can be removed. The means for removing the conductor may be the same as in the first embodiment.

[0198] <Grinding process> In this step, as shown in Fig. 10(d), the side of the silicon substrate on which the conductor 35 is formed opposite to the side on which the non-through holes 31 are opened is ground to obtain a substrate 61 having a silicon through-hole electrode provided with a silicon electrode. That is, in this step, the conductor 35 is exposed by grinding also on the side on which the silicon substrate opposite to the side on which the non-through holes 31 are opened to form a silicon through-hole electrode. In Fig. 10(d), the conductor 35 formed on the side of the silicon substrate on which the non-through holes 31 are opened is removed by the conductor removal step.

[0199] Grinding methods include, for example, mechanical polishing and chemical mechanical polishing.

[0200] In this embodiment, the filling rate of the cured resin 6 in the conductor 35 after the grinding step may satisfy the following condition: The filling rate can be calculated in the same manner as above.

[0201] (a) In a region (see (d) of FIG. 10) from point S21, where line L2 passing through central portion E of the silicon through electrode (center of length L and center of hole diameter D there) and extending in the thickness direction of the substrate intersects with the surface of conductor 35, to a depth of 10 μm, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the internal space of the pores (vacant holes) of the metal body. (b) In the region from point S21 to a depth of 10 to 20 μm, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. (c) In the region from point S21 to a depth of 20 to 30 μm, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal spaces of the metal body. (d) Within a range of ±5 μm from the center E of the silicon through electrode in the thickness direction of the substrate and ±5 μm in a direction perpendicular to the thickness direction of the substrate, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body.

[0202] The ratio L / D of the length L of the through silicon via to the hole diameter D may be the same as in the first embodiment.

[0203] In the method for manufacturing a substrate having a through electrode of this embodiment, the conductor is filled with a cured resin, but the above-mentioned resin impregnation step and resin curing step may be omitted and the through electrode may be formed from a metal body.

[0204] Moreover, the method for manufacturing a substrate having a through electrode according to the second embodiment can further include a wiring formation step similar to the method according to the first embodiment described above.

[0205] (Substrate Having Through Electrodes According to the Second Embodiment) FIG. 10(d) is a cross-sectional view showing one embodiment of a substrate having a silicon through-hole that can be manufactured by the method according to the second embodiment described above. The substrate 61 having a silicon through-hole shown in FIG. 10(d) includes a silicon wafer 1 having through-holes, a silicon substrate having through-holes on both main surfaces, and a conductor 35 filling the through-holes. The conductor 35 includes a copper sintered body having a porous structure and solder scattered in the copper sintered body, and includes a metal body 5 having voids 4, and the metal body 5 includes, as the voids 4, voids present inside the solder and / or voids present between the solder and the copper sintered body. The conductor 35 further includes a resin cured material 6 filling the voids 4.

[0206] The substrate 61 having a silicon through electrode shown in Fig. 10(d) does not have a conductor 35 formed on both main surfaces, but a conductor 35 may be formed on one of the main surfaces. The substrate 61 having a silicon through electrode shown in Fig. 10(d) has a metal coating 2 provided on the wall surface of the through hole, but the metal coating 2 does not have to be provided on the wall surface of the through hole.

[0207] In addition, when the metal particle-containing layer uses a metal particle film containing copper particles, the substrate having the silicon through electrode includes a silicon wafer having through holes, the silicon substrate having through holes communicating with both main surfaces, and a conductor filling the through holes, and the conductor can include a copper sintered body having a porous structure and a resin cured product filled in the pores of the copper sintered body. In this case, the substrate having the silicon through electrode may have a metal coating on both main surfaces of the silicon wafer and on the wall surface of the through hole. In addition, the metal coating may not be provided on the main surface, may be provided only on one main surface, and may not be provided on the wall surface of the through hole. In addition, the substrate having the silicon through electrode may have wiring including a metal coating and a conductor on both main surfaces of the silicon substrate. The wiring may be provided on one main surface of the silicon substrate.

[0208] The filling rate of the cured resin 6 in the conductor 35 included in the substrate 61 having the silicon through electrode may be the same as the filling rate of the cured resin 6 in the conductor 35 after the grinding step.

[0209] (Semiconductor Device According to the Second Embodiment) A semiconductor device manufactured using a base body having a through electrode (substrate having a silicon through electrode) according to the second embodiment will be specifically described with reference to Fig. 11. Fig. 11 is a schematic cross-sectional view showing one embodiment of a semiconductor device. In the semiconductor device 300 shown in Fig. 11, substrates 61 having silicon through electrodes are repeatedly stacked. The substrates 61 having silicon through electrodes are electrically connected to each other.

[0210] In the semiconductor device 300, the filling rate of the cured resin 6 in the conductor 35 may satisfy the following condition. The filling rate can be calculated in the same manner as above.

[0211] (Silicon through-electrode conductor) (a) In a region (see FIG. 11 ) that passes through central portion E of the silicon through electrode (the center of length L and the center of hole diameter D there) from point S22 where line L2 extending in the thickness direction of the substrate intersects with the surface of conductor 35 to a depth of 10 μm, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the internal space of the pores (voids) of the metal body. (b) In the region from point S22 to a depth of 10 to 20 μm, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. (c) In the region from point S22 to a depth of 20 to 30 μm, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal spaces of the metal body. (d) Within a range of ±5 μm from the center E of the silicon through electrode in the thickness direction of the substrate and ±5 μm in a direction perpendicular to the thickness direction of the substrate, the filling rate of the cured resin may be 80 vol. % or more, 90 vol. % or more, or 95 vol. % or more, based on the total volume of the porous internal space of the metal body. EXAMPLES

[0212] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

[0213] <Synthesis of second copper particles> 91.5g (0.94mol) of copper hydroxide (Kanto Chemical Co., Ltd., special grade) was added to 150mL of 1-propanol (Kanto Chemical Co., Ltd., special grade) and stirred, to which 370.9g (2.34mol) of nonanoic acid (Kanto Chemical Co., Ltd., 90% or more) was added. The resulting mixture was heated and stirred at 90°C for 30 minutes in a separable flask. The resulting solution was filtered while still heated to remove undissolved matter. It was then allowed to cool, and the resulting copper nonanoate was suction filtered and washed with hexane until the washing liquid became transparent. The resulting powder was dried in an explosion-proof oven at 50°C for 3 hours to obtain copper nonanoate (II). The yield was 340g (96% by mass).

[0214] 15.01g (0.040mol) of copper (II) nonanoate obtained above and 7.21g (0.040mol) of copper (II) acetate anhydride (Kanto Chemical Co., Ltd., special grade) were placed in a separable flask, 22mL of 1-propanol and 32.1g (0.32mol) of hexylamine (Tokyo Chemical Industry Co., Ltd., purity 99%) were added, and the mixture was heated and stirred at 80°C in an oil bath to dissolve. The mixture was transferred to an ice bath and cooled to an internal temperature of 5°C, after which 7.72mL (0.16mol) of hydrazine monohydrate (Kanto Chemical Co., Ltd., special grade) was stirred in the ice bath. The molar ratio of copper:hexylamine was 1:4. The mixture was then heated and stirred at 90°C in an oil bath. At that time, a reduction reaction accompanied by foaming proceeded, and the reaction was completed within 30 minutes. The inner wall of the separable flask showed a copper luster, and the solution turned dark red. Centrifugation was carried out at 9000 rpm (revolutions per minute) for 1 minute to obtain a solid matter. The process of washing the solid matter with 15 mL of hexane was repeated three times to remove the acid residue, and a powder of copper particles having a copper luster (second copper particles) was obtained.

[0215] The copper particles synthesized above were observed with a transmission electron microscope (manufactured by JEOL Ltd., product name: JEM-2100F). The average major axis of 200 randomly selected copper particles was 104 nm. The shape of the second particles was spherical.

[0216] <Preparation of metal paste> (Examples 1 to 10) The raw materials shown below were mixed in the ratios shown in Table 1 to prepare a metal paste.

[0217] [First copper particle] Flat 1.4 μm: 1100YP (manufactured by Mitsui Mining & Smelting Co., Ltd., average particle size 1.4 μm (D50), product name)

[0218] [Second copper particles] Spherical 104 nm: Copper particles synthesized above

[0219] [Solder particles] SnBi58: SnBi58 solder STC-3 (manufactured by Mitsui Mining & Smelting Co., Ltd., product name, average particle size 4.1 μm (D50), spherical)

[0220] [others] Diethylene glycol: Fujifilm Wako Pure Chemical Industries, Ltd.

[0221] Comparative Example 1 A metal paste was prepared by mixing 70 parts by mass of 1100YP (manufactured by Mitsui Mining & Smelting Co., Ltd., average particle size 1.4 μm (D50), product name) as the first copper particles, 30 parts by mass of the copper particles synthesized above as the second copper particles, 5 parts by mass of diethylene glycol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), and 5 parts by mass of a resin component. As the resin component, a mixture of an acrylic resin as an organic binder and a mixture of carbitol and terpineol as an organic solvent (the mass ratio of carbitol and terpineol in the mixture was carbitol:terpineol = 1:1) mixed in a mass ratio of 1:2 was used.

[0222] <Silicon substrate preparation process> (Examples 1 to 10 and Comparative Example 1) A silicon substrate was prepared with through holes, with a titanium layer, a nickel layer, and a copper layer formed in that order on both main surfaces and on the wall surfaces of the through holes. The silicon substrate had a diameter of 6 inches and a thickness of 500 μm, and the titanium layer, nickel layer, and copper layer were formed in that order by sputtering. The diameter of the through holes in the silicon substrate is shown in Table 1.

[0223] <Preparation of metal particle film> (Examples 1 to 10) The metal paste prepared above was applied to a 100 μm thick PET film using an automatic film applicator (manufactured by Allgood Co., Ltd., product name) so that the coating thickness was about 150 μm. Next, using a hot plate, the film was dried at 30° C. for 1 hour so that the metal particle concentration of the coating film was about 95 mass %. In this way, a metal particle film was obtained in which a metal particle-containing layer having a thickness of 80 μm was provided on the PET film.

[0224] <Metal body formation process> (Examples 1 to 10) -Filling process- The prepared laminate of the silicon substrate and the metal particle film was pressed at room temperature in air at a pressure of 0.5 MPa using a bonding device VJ-35 (manufactured by Ayumi Industries Co., Ltd., product name), and the metal particle composition was filled into the through holes. The metal particle composition protruded from the side of the silicon substrate opposite to the side where the metal particle film was bonded.

[0225] A metal paste mixed in the ratio shown in Table 1 was applied to the surface of the silicon substrate from which the metal particle composition protruded using an automatic film applicator (product name, manufactured by Allgood Co., Ltd.), the PET film was removed, and the substrate was dried in air at 90° C. for 10 minutes. After drying, a metal particle composition layer 30 μm thick was formed on both main surfaces of the silicon substrate.

[0226] -Firing process- The silicon substrate on which the metal particle composition layer was formed was placed in a tube furnace (manufactured by AVC Corporation), and argon gas was flowed at 1 L / min to replace the air in the tube furnace with argon gas. The metal paste was then sintered by heating for 10 minutes and sintering at 225°C for 60 minutes while flowing hydrogen gas at 300 mL / min. The argon gas was then changed to 0.3 L / min, cooled, and taken out into the air at 50°C or less to obtain a metal body-filled silicon substrate in which metal bodies were formed in the through holes and on both main surfaces. The thickness of the metal bodies formed on both main surfaces of the silicon substrate was 25 μm.

[0227] Comparative Example 1 The prepared metal paste was applied to both main surfaces of the prepared silicon substrate with a metal spatula, and the metal paste was filled into the through holes. After application, the metal paste was dried in the air at 90°C for 10 minutes. After drying, a metal paste layer with a thickness of 30 μm was formed on the silicon substrate.

[0228] The silicon substrate on which the metal paste layer was formed was placed in a tube furnace (manufactured by AVC Corporation), and argon gas was flowed at 1 L / min to replace the air in the tube furnace with argon gas. The metal paste was then sintered by sintering under conditions of heating for 10 minutes and 250°C for 60 minutes while flowing hydrogen gas at 300 mL / min. The argon gas was then changed to 0.3 L / min, cooled, and taken out into the air at 50°C or less to obtain a metal body-filled silicon substrate as a silicon substrate having a silicon through electrode. The thickness of the metal body formed on both main surfaces of the sintered silicon substrate was 25 μm.

[0229] [Measuring the porosity of metal bodies] (Examples 1 to 10 and Comparative Example 1) Using a focused ion beam processing observation device (manufactured by Hitachi High-Technologies Corporation, product name: MI4050), the cross section of the center of the through hole of the silicon substrate filled with a metal body and the cross section of the metal body provided on the main surface of the silicon substrate were exposed by a focused ion beam, and the cross sections were observed. When observing the cross section of the center of the through hole, a range of ±5 μm in the thickness direction of the silicon substrate and ±5 μm in the direction perpendicular to the thickness direction of the silicon substrate from the center of the metal body filled in the through hole was observed. When observing the cross section of the metal body provided on the main surface of the silicon substrate, a range of 10 μm in the thickness direction of the silicon substrate and 10 μm in the direction perpendicular to the thickness direction of the silicon substrate was observed in a region up to 5 μm from the surface of the metal body formed on the main surface of the silicon substrate.

[0230] For the observation, a scanning electron microscope (Hitachi High-Technologies Corporation, product name: S-3700N) was used at a magnification of 10,000 times to take cross-sectional images (approximately 10 μm square) of the metal body. Five observation points were made. The obtained cross-sectional images were binarized using image analysis software (Adobe Photoshop (registered trademark) Elements) so that the metal parts and the porous parts were separated. For each of the five observation points, the ratio of the area of ​​the porous parts to the total area of ​​the cross section of the metal body was taken as the porosity. The average value of the porosity of the five observation points was taken as the porosity of the metal body. The results are shown in Table 1.

[0231] <Resin impregnation process> (Examples 1 to 10) The curable resin composition shown below was applied to one side of the metal body-filled silicon substrate by a roll coater. Next, the metal body-filled silicon substrate was placed in a container, and the container was suctioned so that the gauge pressure was 100 KPa to create a vacuum state. The metal body-filled silicon substrate was held in a vacuum state for 10 minutes, and then the metal body-filled silicon substrate was removed from the container. It was confirmed that the metal body in the through hole was impregnated with the curable resin composition, and the curable resin composition reached the opposite side of the metal body in the through hole to the side to which the curable resin composition was applied. The curable resin composition remaining on the application surface of the curable resin composition of the metal body-filled silicon substrate was removed with a rubber spatula. Next, the curable resin composition was applied to the opposite side to the side to which the curable resin composition was applied by a roll coater, and the curable resin composition remaining on the surface of the metal body-filled silicon substrate was removed as much as possible with a rubber spatula.

[0232] [Curable resin composition] YDF-170 (product name of bisphenol F type epoxy resin, manufactured by Tohto Kasei Co., Ltd., epoxy equivalent = 170): 95 parts by mass 2PZ-CN (trade name of imidazole compound manufactured by Shikoku Kasei Co., Ltd.): 5 parts by mass

[0233] Comparative Example 1 The resin impregnation step was not performed.

[0234] <Resin curing process> (Examples 1 to 10) The silicon substrate with the metal body impregnated with the curable resin composition was held in a nitrogen atmosphere at 180° C. for 1 hour to obtain a silicon substrate having a silicon through electrode containing a cured resin.

[0235] Comparative Example 1 The resin impregnation step was not performed.

[0236] <Conductor removal process> (Examples 1 to 10 and Comparative Example 1) Both sides of the substrate with silicon through-hole electrodes were mechanically polished until the thickness of the metal body on both sides of the substrate with silicon through-hole electrodes was 20 μm. A ceramic jig (Kemet Japan Co., Ltd.) was used as the sample stage to which the substrate with silicon through-hole electrodes was attached, and Alcowax (Nikka Seiko Co., Ltd.) was used as the material to attach the substrate with silicon through-hole electrodes to the sample stage. In addition, DP-Suspension P-3 μm, 1 μm, and 1 / 4 μm (Struers Co., Ltd.) were used as the abrasives, in that order.

[0237] [Filling rate of cured resin in conductor] (Examples 1 to 10 and Comparative Example 1) The substrate having the silicon through-hole electrode that had been mechanically polished was cut in the thickness direction, and the cross section of the center of the through-hole of the silicon substrate and the cross section of the conductor provided on the main surface of the silicon substrate were exposed by a focused ion beam, and these cross sections were observed. When observing the cross section of the center of the through-hole of the silicon substrate, a range of ±5 μm from the center of the through-hole in the thickness direction of the silicon substrate and ±5 μm in the direction perpendicular to the thickness direction of the silicon substrate was observed. When observing the cross section of the conductor provided on the main surface of the silicon substrate, a range of 10 μm in the thickness direction of the silicon substrate and 10 μm in the direction perpendicular to the thickness direction of the silicon substrate was observed in a region from the surface of the conductor provided on the main surface of the silicon substrate to 5 μm. A focused ion beam processing observation device (manufactured by Hitachi High-Technologies Corporation, product name: MI4050) was used. For the observation, a scanning electron microscope (manufactured by Hitachi High-Technologies Corporation, product name: S-3700N) was used at a magnification of 10,000 times, and a cross-sectional image of the conductor (about 10 μm square) was taken. Five observation points were observed. The obtained cross-sectional image was binarized using image analysis software (Adobe Photoshop (registered trademark) Elements) so that the metal part, the cured resin part, and the space in the porous part that was not filled with the cured resin were separated. For each of the five observation points, the ratio of the area of ​​the space in the porous part that was not filled with the cured resin to the total area of ​​the cross section of the conductor was calculated, and this was taken as the porosity. The average value of the porosity of the five observation points was taken as the porosity of the conductor. The porosity of the metal body and the porosity of the conductor were substituted into the following formula (1) to calculate the filling rate of the cured resin in the conductor. Filling rate of cured resin in conductor (%) = [(B A) / B] × 100 Equation (1) [In formula (1), A represents the porosity (%) of the conductor, and B represents the porosity (%) of the copper sintered body.]

[0238] <Wiring formation process (resist formation, etching, and resist removal)> (Examples 1 to 10 and Comparative Example 1) A dry film for ultraviolet-curable etching resist H-W425 (trade name, manufactured by Hitachi Chemical Co., Ltd.) was pressed by a laminator onto the surfaces of the metal bodies on both sides of the substrate having the silicon through electrode that had been subjected to mechanical polishing treatment. After that, a photomask was aligned to expose the wiring pattern, and the wiring having a wiring pattern of 300 μm × 600 μm was formed through resist development, etching of the copper sintered body, and resist removal, thereby obtaining a substrate having the silicon through electrode (test piece 55) shown in FIG. 12. In the obtained substrate having the silicon through electrode (test piece 55), the conductors filled in the through holes are electrically connected by the conductors (wiring) provided on the substrate surface.

[0239] [Rating 1] (Examples 1 to 10 and Comparative Example 1) The test pieces obtained above were subjected to the following measurements and evaluations.

[0240] [Initial resistance value] The interconnection resistance was measured as the initial resistance of the substrate (test piece 55) having the silicon through-hole electrode. When the diameter of the through-hole of the silicon substrate was 20 μm, the resistance of 20 through-holes interconnected was measured; when the diameter of the through-hole of the silicon substrate was 30 μm, the resistance of 30 through-holes interconnected was measured; when the diameter of the through-hole of the silicon substrate was 50 μm, the resistance of 30 through-holes interconnected was measured; when the diameter of the through-hole of the silicon substrate was 100 μm, the resistance of 100 through-holes interconnected was measured; and when the diameter of the through-hole of the silicon substrate was 200 μm, the resistance of 200 through-holes interconnected was measured. The measured interconnection resistance was evaluated according to the following criteria. Evaluations of B or higher were judged to be good. The results are shown in Table 1. A: Resistance value is less than 10mΩ B: Resistance value is 10mΩ or more and less than 30mΩ C: Resistance is 30mΩ or more and less than 100mΩ D: Resistance is 100mΩ or more and less than 500mΩ E: Resistance value is 500mΩ or more

[0241] [Temperature cycle connectivity test] A substrate (test piece 55) having a silicon through-hole electrode was set in a temperature cycle tester (TSA-72SE-W, manufactured by Espec Corporation), and a temperature cycle connection reliability test was carried out under the following conditions: low temperature side: -40°C, 15 minutes, room temperature: 2 minutes, high temperature side: 125°C, 15 minutes, defrost cycle: automatic, number of cycles: 50, 100, 300, 500 cycles. When the diameter of the through-hole of the silicon substrate was 20 μm, the resistance value of 20 through-holes connected together was measured; when the diameter of the through-hole of the silicon substrate was 30 μm, the resistance value of 30 through-holes connected together was measured; when the diameter of the through-hole of the silicon substrate was 50 μm, the resistance value of 30 through-holes connected together was measured; when the diameter of the through-hole of the silicon substrate was 100 μm, the resistance value of 100 through-holes connected together was measured; and when the diameter of the through-hole of the silicon substrate was 200 μm, the resistance value of 200 through-holes connected together was measured. The measured connection resistance was evaluated according to the following criteria. Those that were evaluated as B or higher after 500 heat cycle tests were judged to be good. The results are shown in Table 1. A: Resistance change rate is less than 1% of the initial resistance value B: Resistance change rate is 1% or more and less than 3% of the initial resistance value C: Resistance change rate is 3% or more and less than 5% of the initial resistance value D: Resistance change rate is 5% or more and less than 10% of the initial resistance value E: Resistance change rate is 10% or more but less than 20% of the initial resistance value F: Resistance change rate is 20% or more compared to the initial resistance value

[0242] [Cracked circuit board] The substrate (test piece 55) having the silicon through electrode was visually inspected to confirm the presence or absence of cracks in the silicon substrate. The absence of cracks was evaluated as ◯, and the presence of even partial cracks was evaluated as ×. The results are shown in Table 1.

[0243] [airtightness] The airtightness of the substrate (test piece 55) having a silicon through electrode was evaluated. The evaluation was performed using a helium leak detector (UL200 manufactured by LEYBOLD). Specifically, the substrate having the silicon through electrode was set on a jig, and a vacuum was drawn until the inlet pressure of the measuring device reached 5 Pa. When the inlet pressure reached 5 Pa, helium pressure (0.1 MPa) was applied for 30 seconds, after which the amount of leakage was measured and evaluated according to the following criteria. The results are shown in Tables 1 to 6. A: Leak rate is 1×10 -11 Pa·m 3 / sec B: Leak amount is 1×10 -11 More than 1×10 -10 Pa·m 3 / sec C: Leak amount is 1×10 -10 More than 1×10 -9 Pa·m 3 / sec D: Leak amount is 1×10 -9 More than 1×10 -8 Pa·m 3 / sec E: Leak amount is 1×10 -8 More than 1×10 -6 Pa·m 3 / sec F: Leak amount is 1×10 -6 Pa·m 3 / sec or more.

[0244] [Rating 2] (Examples 1 to 10 and Comparative Example 1) A substrate having a silicon through-hole electrode was obtained in the same manner except that a 20 mm × 2 mm wiring pattern was formed in the wiring formation process. 2 The stud pins were soldered vertically to prepare test pieces. The test pieces were subjected to the following evaluations.

[0245] [Wiring adhesion - pull strength] The test piece was fixed, the stud pin was gripped by the chuck of the tensile tester, and pulled vertically upward at an ascending speed of 50 mm / min, and the fracture load was measured when the metal body on the main surface of the silicon substrate peeled off from the silicon substrate. The adhesion strength was calculated using the following formula from the obtained fracture load measurement and the fracture area of ​​the metal body. The measurement value was the average of 10 points and was evaluated according to the following criteria. The results are shown in Table 1.

[0246] Adhesion strength (MPa) = breaking load (kgf) / breaking area (mm2) x 9.8 (N / kgf). A: Adhesion strength (MPa) is 50 MPa or more B: Adhesion strength (MPa) is 40 MPa or more and less than 50 MPa C: Adhesion strength (MPa) is 30 MPa or more but less than 40 MPa D: Adhesion strength (MPa) is 20 MPa or more but less than 30 MPa E: Adhesion strength (MPa) is 5 MPa or more and less than 20 MPa F: Adhesion strength (MPa) is less than 5MPa

[0247] [Rating 3] (Examples 1 to 10 and Comparative Example 1) A substrate having a silicon through electrode was obtained in the same manner, except that five wiring patterns of 20 mm×2 mm were formed in the wiring formation step. The substrate was evaluated as follows.

[0248] [Wiring formability - presence or absence of cracks -] The substrate having the silicon through-hole electrode was inspected by an optical microscope to check for the presence or absence of cracks (length 0.5 mm or more) in the wiring pattern. The magnification was 500 times, and the evaluation was based on the following criteria. The results are shown in Table 1. A: No cracks B: 1 or more but less than 2 cracks C: 2 or more but less than 5 cracks D: 5 or more but less than 10 cracks E: 10 or more cracks but less than 20 F: 20 or more cracks

[0249] [Rating 4] (Examples 1 to 10 and Comparative Example 1) The metal paste prepared above was applied to a silicon wafer having a thickness of 500 μm using an automatic film applicator (manufactured by Allgood Co., Ltd., product name) so that the coating thickness was about 150 μm. The coating area was about 5 cm × about 10 cm. Next, using a hot plate, the coating was dried at 30 ° C for 1 hour so that the concentration of metal particles in the coating film was about 95 mass %. In this way, a silicon wafer having a metal particle-containing layer having a thickness of about 80 μm was obtained. The silicon substrate on which the metal particle composition layer was formed was placed in a tube furnace (manufactured by AVC Co., Ltd.), and argon gas was flowed at 1 L / min to replace the air in the tube furnace with argon gas. Thereafter, the metal paste was sintered by sintering under the conditions of heating for 10 minutes and at 225 ° C for 60 minutes while flowing hydrogen gas at 300 mL / min. Thereafter, the argon gas was changed to 0.3 L / min, cooled, and taken out into the air at 50 ° C or less to obtain a silicon substrate on which a metal body was formed.

[0250] [Volume resistivity] The volume resistivity of the conductor formed on the silicon substrate was measured. The volume resistivity was calculated from the sheet resistance measured with a four-point needle sheet resistance meter (Mitsubishi Analytech, product name: Loresta GP) and the film thickness obtained with a non-contact surface / layer cross-sectional shape measurement system (VertScan, Ryoka Systems Co., Ltd.). The results are shown in Table 1.

[0251] [Observation results of gaps around solder] 13 and 14 show cross-sectional images (approximately 20 μm square) of the metal body of the metal body-filled silicon substrate produced in Example 6, taken using a digital microscope (Keyence Corporation, product name: VHX-6000). As shown in FIGS. 13 and 14, the metal body includes a copper sintered body, a solder (SiBi58), and voids, and the voids exist in the copper sintered body, inside the solder, and on the outer periphery of the solder (between the solder and the copper sintered body). The voids 4a shown in FIG. 13 exist inside the solder 14a, and the voids 4b shown in FIG. 14 exist on the outer periphery of the solder 14b.

[0252] Fig. 15 shows a cross-sectional image (approximately 10 μm × 12 μm square) of the metal body taken with a digital microscope (Keyence Corporation, product name: VHX-6000) for the metal body-filled silicon substrate produced in Comparative Example 1. As shown in Fig. 15, a crack 18 was observed inside the copper sintered body 12d constituting the metal body.

[0253] In the metal body-filled silicon substrates produced in the examples, it is believed that the occurrence of the above-mentioned cracks is suppressed by the presence of solder dots originating from the solder particles.

[0254] [Table 1] [Explanation of symbols]

[0255] Reference Signs List 1...silicon wafer, 2...metal coating, 3...metal particle composition, 4...voids (porous, voids), 5...metal body, 6...resin hardened product, 8...etching resist, 9...wiring, 12...copper sintered body, 14...solder, 15...fine bump, 20...hardened adhesive, 25...interposer substrate, 27...wiring, 30...through hole, 31...non-through hole, 35...conductor, 40, 41...silicon substrate, 50, 60...silicon substrate filled with metal body, 51, 52, 61...substrate with silicon through electrode, 55...test piece, 70...metal particle film, 71...support film, 72...metal particle-containing layer, 100, 200, 300...semiconductor device, A...pressure jig

Claims

1. A metal particle-containing layer is provided on the support film and contains metal particles and a volatile dispersion medium, the metal particle-containing layer has a thickness of 100 μm or less and a concentration of the metal particles of 94 mass % or more; the metal particles include copper particles, The metal particle film, wherein the copper particles include first copper particles having a particle size of 0.8 μm or more and second copper particles having a particle size of 0.5 μm or less.

2. A metal particle-containing layer is provided on the support film and contains metal particles and a volatile dispersion medium, the metal particle-containing layer has a thickness of 100 μm or less and a concentration of the metal particles of 94 mass % or more; A metal particle film, wherein the metal particles further comprise solder particles.

3. A metal particle-containing layer (excluding those containing a resin component) containing metal particles and a volatile dispersion medium provided on the support film, The metal particle film, wherein the metal particle-containing layer has a thickness of 100 μm or less and a concentration of the metal particles of 94 mass % or more.

4. The metal particle film of claim 2 or 3, wherein the metal particles comprise copper particles.

5. 5. The metal particle film of claim 4, wherein the copper particles include first copper particles having a particle size of 0.8 μm or more and second copper particles having a particle size of 0.5 μm or less.

6. The metal particle film of claim 1 or 5, wherein the first copper particles are flat.

7. The metal particle film of any one of claims 3 to 6, wherein the metal particles further comprise solder particles.

8. The metal particle film of claim 2 or 7, wherein the solder particles comprise tin or a tin alloy.

9. 8. The metal particle film of claim 2 or 7, wherein the solder particles are In--Sn, In--Sn--Ag, Sn--Bi, Sn--Bi--Ag, Sn--Ag--Cu, or a Sn--Cu based alloy.

10. A method for producing the metal particle film of any one of claims 1 to 9, comprising the steps of: A step of applying a metal paste containing metal particles and a volatile dispersion medium, the metal particles having a concentration of less than 92 mass %, onto a support film to provide a metal paste layer; drying the metal paste layer to form a metal particle-containing layer having a thickness of 100 μm or less and a metal particle concentration of 94 mass % or more; A method for producing a metal particle film comprising:

11. The method of claim 10 , wherein the metal paste is applied onto the support film by screen printing.

12. The method includes a preparation step of preparing an insulating substrate having through holes, the through holes communicating with both main surfaces of the substrate, and a conductor formation step of forming a conductor in the through holes, the conductor forming step includes a metal body forming step of forming a metal body having a void so as to fill at least the through hole, the metal body forming step includes a filling step of pressing a metal particle film, which includes a support film and a metal particle-containing layer provided on the support film, against the substrate so that the metal particle-containing layer of the metal particle film is in contact with the substrate, thereby filling the through holes of the substrate with a metal particle composition; a firing step of firing the metal particle composition to form the metal body; having the metal particle-containing layer contains metal particles and a volatile dispersion medium, The method for producing a substrate having a through electrode, wherein the metal particle-containing layer has a thickness of 100 μm or less.

13. The method for producing a substrate having a through electrode according to claim 12 , wherein the metal particles include copper particles.

14. 14. The method for manufacturing a substrate having a through electrode according to claim 13, wherein the copper particles include first copper particles having a particle size of 0.8 μm or more and second copper particles having a particle size of 0.5 μm or less.

15. The method for producing a substrate having a through electrode according to claim 14 , wherein the first copper particles are flat.

16. The method for manufacturing a substrate having a through electrode according to any one of claims 12 to 15, wherein the metal particles further include solder particles.

17. The method for manufacturing a substrate having a through electrode according to claim 16 , wherein the solder particles contain tin or a tin alloy.

18. 17. The method for manufacturing a substrate having a through electrode according to claim 16, wherein the solder particles are In--Sn, In--Sn--Ag, Sn--Bi, Sn--Bi--Ag, Sn--Ag--Cu, or a Sn--Cu based alloy.

19. The method includes a preparation step of preparing an insulating substrate having through holes, the through holes communicating with both main surfaces of the substrate, and a conductor formation step of forming a conductor in the through holes, the conductor forming step includes a metal body forming step of forming a metal body having a void so as to fill at least the through hole, the metal body forming step includes a filling step of pressing a metal particle film, which includes a support film and a metal particle-containing layer (excluding those containing a resin component) provided on the support film, against the base so that the metal particle-containing layer of the metal particle film is in contact with the base, thereby filling the through holes of the base with a metal particle composition; a firing step of firing the metal particle composition to form the metal body; having the metal particle-containing layer contains metal particles and a volatile dispersion medium, The method for producing a substrate having a through electrode, wherein the metal particle-containing layer has a thickness of 100 μm or less.

20. The method includes a preparation step of preparing a substrate including an insulating substrate having non-through holes formed therein, the substrate having one main surface on which the non-through holes are opened, a conductor formation step of forming conductors in the non-through holes, and a grinding step of providing through electrodes by grinding a surface of the substrate on which the conductors are formed opposite to the surface on which the non-through holes are opened, the conductor forming step includes a metal body forming step of forming a metal body having voids so as to fill at least the non-through holes, the metal body forming step includes a filling step of pressing a metal particle film, which includes a support film and a metal particle-containing layer (excluding those containing a resin component) provided on the support film, against the base so that the metal particle-containing layer of the metal particle film is in contact with the base, thereby filling the non-penetrating holes of the base with a metal particle composition; a firing step of firing the metal particle composition to form the metal body; having the metal particle-containing layer contains metal particles and a volatile dispersion medium, The method for producing a substrate having a through electrode, wherein the metal particle-containing layer has a thickness of 100 μm or less.

21. The method for producing a substrate having a through electrode according to claim 19 or 20, wherein the metal particles include copper particles.

22. 22. The method for manufacturing a substrate having a through electrode according to claim 21, wherein the copper particles include first copper particles having a particle size of 0.8 μm or more and second copper particles having a particle size of 0.5 μm or less.

23. The method for producing a substrate having a through electrode according to claim 22 , wherein the first copper particles are flat.

24. The method for manufacturing a substrate having a through electrode according to any one of claims 19 to 23, wherein the metal particles further include solder particles.

25. The method for manufacturing a substrate having a through electrode according to claim 24 , wherein the solder particles include tin or a tin alloy.

26. 25. The method for manufacturing a substrate having a through electrode according to claim 24, wherein the solder particles are In--Sn, In--Sn--Ag, Sn--Bi, Sn--Bi--Ag, Sn--Ag--Cu, or a Sn--Cu based alloy.

27. The conductor forming step includes: a resin impregnation step of impregnating the metal body with a curable resin composition; a resin curing step of curing the curable resin composition impregnated in the metal body; The method for producing a substrate having a through electrode according to any one of claims 19 to 26, further comprising:

28. The method for manufacturing a substrate having a through electrode according to any one of claims 12 to 27, further comprising a conductor removing step of removing at least a portion of the conductor formed on the main surface of the substrate.

29. The method for producing a substrate having a through electrode according to any one of claims 12 to 28, wherein the insulating substrate is a silicon wafer, and the through electrode is a silicon through electrode.

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