JP2019147988A - Metal film, structure, composite material, production method of metal film, production method of structure, and production method of composite material - Google Patents

Abstract

To provide a metal film that can suppress defects such as a disarray of micropores of an anodic oxide film, a structure and a composite material that use the metal film, a production method of the metal film, a production method of the structure, and a production method of the composite material.SOLUTION: A metal film is used for forming an anodic oxide film, is composed of aluminum with purity of 99.9 mass% or more, and has the thickness of 5 μm or more, in which the number of second phase particles that are isolated by the thermal phenol method is less than 10/mm.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a metal film made of aluminum having a purity of 99.9% by mass or more, a structure and a composite material using the metal film, a method for manufacturing the metal film, a method for manufacturing the structure, and a method for manufacturing the composite material. In particular, the present invention relates to a metal film used for forming an anodized film, a structure and a composite material using the metal film, a metal film manufacturing method, a structure manufacturing method, and a composite material manufacturing method.

In recent years, an attempt has been made to configure a functional member using an anodic oxide film such as aluminum.
For example, Patent Document 1 describes anodized porous alumina that can be applied to various functional devices. The anodized porous alumina of Patent Document 1 has a pore period of 720 nm or more, and regularly arranged pores are arranged in an ideal triangular lattice shape in a range of 4 × 4 in the vertical and horizontal directions. Is anodized.

In addition, a plurality of through holes penetrating in the thickness direction can be formed in the anodized film. A microstructure formed by introducing a conductive substance such as metal or an organic substance having a functional group into the through hole is, for example, a battery electrode, a gas permeable membrane, a sensor, a biological culture container, an electromagnetic wave (light, radiation). ) Applications such as shielding films, light emitting elements, optical elements and anisotropic conductive members are expected.
Here, an anisotropic conductive member (adhesive) using a resin film in which conductive particles are dispersed is inserted between an electronic component such as a semiconductor element and a circuit board, and the electronic component and circuit are simply pressed. Since electrical connection between the substrates can be obtained, it is widely used as an electrical connection member such as an electronic component including an image display element and a driver circuit, and an inspection connector for performing a function inspection.
In order to cope with downsizing of the electrodes of each element, a new anisotropic conductive member using conductive wiring penetrating the top and bottom of the film has been developed and proposed in addition to the improvement by dispersion control of conductive particles. .
In addition, for electronic components such as semiconductor elements, there is a significant demand for downsizing mainly for reduction in height and area. The conventional method of directly connecting the wiring board such as wire bonding is difficult to cope with the low profile, and when using solder bonding such as flip chip bonding, it is necessary to secure a certain size of electrode. Difficult to make area. As means for solving these problems, an anisotropic conductive member made of a fine structure in which an insulating base material is filled with metal has been proposed as an electronic connection member.

As the fine structure, for example, Patent Document 2 describes a metal-filled fine structure in which a through hole is provided in an insulating base material and a metal is filled in the through hole. The insulating base material of patent document 2 is comprised with the anodic oxide film of aluminum. In the insulating substrate, the average opening diameter of the through holes is 10 to 5000 nm, the average depth of the through holes is 10 to 1000 μm, and the density of the through holes is 1 × 10 ⁶ to 1 × 10 ¹⁰ pieces / a mm ^2.

Japanese Patent Laid-Open No. 2018-3048 JP 2011-202194 A

  The anodized film is formed by anodizing an aluminum material as in Patent Document 2 described above. At this time, a through-hole called a micropore is also formed. Various applications using anodic oxide films, such as capacitors, battery electrodes, gas permeable films, sensors, anisotropic conductive members, etc. It is preferable that there are no defects. In order to reduce defects such as disorder of the arrangement of micropores, measures such as increasing the purity of aluminum have been taken. However, in order to further improve the performance, it is not sufficient to further reduce defects such as disturbance of the arrangement of micropores.

  An object of the present invention is to provide a metal film that can suppress defects such as disorder of the arrangement of micropores in the anodized film, a structure and a composite material using the metal film, a method for manufacturing the metal film, a method for manufacturing the structure, and It is providing the manufacturing method of a composite material.

In order to achieve the above object, the present invention is a metal film used for forming an anodized film, which is made of aluminum having a purity of 99.9% by mass or more and is isolated by a hot phenol method. A metal film having a number of particles of less than 10 ⁴ / mm ³ and a thickness of 5 μm or more is provided.
The surface roughness Rt is preferably 0.1 μm or less.

The present invention is a metal film having a multi-layered structure used for forming an anodic oxide film, which is made of aluminum having a purity of 99.9% by mass or more, and the number of second phase particles isolated by a hot phenol method. The first metal layer having a thickness of less than 10 ⁴ pieces / mm ³ and having a thickness of 5 μm or more, and a second metal layer having a composition different from that of the first metal layer, The thickness ratio with respect to the thickness of a metal film is less than 10%, and the metal film by which the 1st metal layer is arrange | positioned at the outermost layer is provided.
The first metal layer preferably has a surface roughness Rt of 0.1 μm or less.
The second metal layer is preferably a valve metal.

The present invention provides a structure which is formed of an anodic oxide film having a through hole, which is configured using the metal film of the present invention, and the straight tube ratio of the through hole is 98% or more. .
The present invention provides a composite material having the structure of the present invention and a conductor filled in a through hole of the structure.
The present invention is a method for producing a metal film used for forming an anodic oxide film, and includes a film forming step of forming a film at a cooling rate of 20 ° C./second or more using aluminum having a purity of 99.9% by mass or more. The present invention provides a method for producing a metal film.
It is preferable to have a flattening step for flattening the surface after the film forming step.
This invention provides the manufacturing method of a structure which has the process of implementing an anodizing film which has at least anodizing to the metal film of this invention, and has a through-hole.
The anodization is preferably performed at least once.

The present invention includes a step of performing at least anodization on the metal film of the present invention to form an anodized film having a through hole, and a step of filling a through hole formed by anodizing with a conductive material. A method for manufacturing a material is provided.
The anodization is preferably performed at least once.

  According to the present invention, a metal film capable of suppressing defects such as disorder of the arrangement of micropores, a structure and a composite material using the metal film, a method for producing a metal film, a method for producing the structure, and a production of the composite material A method can be provided.

It is a schematic diagram which shows the 1st example of the metal film of embodiment of this invention. It is a schematic diagram which shows the 2nd example of the metal film of embodiment of this invention. It is a schematic diagram which shows the 3rd example of the metal film of embodiment of this invention. It is a schematic diagram which shows the 4th example of the metal film of embodiment of this invention. It is a schematic diagram which shows the 5th example of the metal film of embodiment of this invention. It is a schematic diagram which shows an example of the manufacturing method of the 1st example of the metal film of embodiment of this invention. It is a schematic diagram which shows 1 process of an example of the manufacturing method of the 2nd example of the metal film of embodiment of this invention. It is a schematic diagram which shows 1 process of an example of the manufacturing method of the 2nd example of the metal film of embodiment of this invention. It is typical sectional drawing which shows an example of the structure of embodiment of this invention. It is typical sectional drawing which shows an example of the composite material of embodiment of this invention. It is a top view which shows an example of the composite material of embodiment of this invention. It is typical sectional drawing which shows 1 process of the 1st aspect of the manufacturing method of the composite material of embodiment of this invention. It is typical sectional drawing which shows 1 process of the 1st aspect of the manufacturing method of the composite material of embodiment of this invention. It is typical sectional drawing which shows 1 process of the 1st aspect of the manufacturing method of the composite material of embodiment of this invention. It is typical sectional drawing which shows 1 process of the 1st aspect of the manufacturing method of the composite material of embodiment of this invention. It is typical sectional drawing which shows 1 process of the 1st aspect of the manufacturing method of the composite material of embodiment of this invention. It is typical sectional drawing which shows 1 process of the 2nd aspect of the manufacturing method of the composite material of embodiment of this invention. It is typical sectional drawing which shows 1 process of the 2nd aspect of the manufacturing method of the composite material of embodiment of this invention. It is typical sectional drawing which shows 1 process of the 2nd aspect of the manufacturing method of the composite material of embodiment of this invention. It is typical sectional drawing which shows 1 process of the 3rd aspect of the manufacturing method of the composite material of embodiment of this invention. It is typical sectional drawing which shows 1 process of the 3rd aspect of the manufacturing method of the composite material of embodiment of this invention. It is a schematic diagram which shows an example of the supply form of the composite material manufactured by the 3rd aspect of the manufacturing method of the composite material of embodiment of this invention. It is a schematic diagram which expands and shows the principal part of an example of the supply form of the composite material manufactured by the 3rd aspect of the manufacturing method of the composite material of embodiment of this invention. It is a schematic diagram which shows one process of an example of a smoothing process. It is a schematic diagram which shows one process of an example of a smoothing process. It is a schematic diagram which shows one process of an example of a smoothing process. It is a schematic diagram which shows an example of the voltage drop pattern at the time of falling from the voltage in an anodizing process to the voltage in a holding process. It is a schematic diagram which shows the other example of the voltage drop pattern at the time of falling from the voltage in an anodizing process to the voltage in a holding process. It is a typical sectional view showing the 1st example of a semiconductor package. It is a typical sectional view showing the 2nd example of a semiconductor package. It is typical sectional drawing which shows the 3rd example of a semiconductor package. It is typical sectional drawing which shows the 4th example of a semiconductor package. It is typical sectional drawing which shows the 5th example of a semiconductor package. It is typical sectional drawing which shows the structure which laminated | stacked the semiconductor package board | substrate. It is typical sectional drawing which shows the 6th example of a semiconductor package. It is typical sectional drawing which shows the 7th example of a semiconductor package. It is typical sectional drawing for demonstrating a coaxial structure. It is a schematic plan view for demonstrating a coaxial structure. It is a schematic diagram which shows the 1st example of the electronic device of embodiment of this invention. It is typical sectional drawing which shows an example of a structure of the terminal of the semiconductor element of the electronic device of embodiment of this invention. It is a schematic diagram which shows the 2nd example of the electronic device of embodiment of this invention. It is a schematic diagram which shows the 3rd example of the electronic device of embodiment of this invention. It is a schematic diagram which shows the 4th example of the electronic device of embodiment of this invention. It is a schematic diagram which shows the 5th example of the electronic device of embodiment of this invention. It is a schematic diagram which shows the 6th example of the electronic device of embodiment of this invention. It is a schematic diagram which shows the 7th example of the electronic device of embodiment of this invention. It is a schematic diagram which shows the 8th example of the electronic device of embodiment of this invention.

Hereinafter, based on preferred embodiments shown in the accompanying drawings, a metal film, a structure, a composite material, a metal film manufacturing method, a structure manufacturing method, and a composite material manufacturing method of the present invention will be described in detail. .
In addition, the figure demonstrated below is an illustration for demonstrating this invention, and this invention is not limited to the figure shown below.
In the following, “to” indicating a numerical range includes numerical values written on both sides. For example, when ε is a numerical value α to a numerical value β, the range of ε is a range including the numerical value α and the numerical value β, and α ≦ ε ≦ β in mathematical symbols.
Unless otherwise specified, angles such as “an angle represented by a specific numerical value”, “parallel”, “vertical”, and “orthogonal” include an error range generally allowed in the corresponding technical field.
Further, regarding temperature, unless otherwise specified, an error range generally allowed in the corresponding technical field is included. Further, “same” includes an error range generally allowed in the corresponding technical field.

(Metal film)
The metal film is used for forming an anodized film.
FIG. 1 is a schematic diagram showing a first example of a metal film according to an embodiment of the present invention.
The metal film 10 shown in FIG. 1 is made of aluminum having a purity of 99.9% by mass or more, and the number of second phase particles isolated by the hot phenol method is less than 100 particles / mm ³ , and the thickness t is 5 μm or more. The metal film 10 has a single layer structure.
As long as the metal film 10 is aluminum having a purity of 99.9% by mass or more, the other composition is not particularly limited. For example, the metal film 10 may contain inevitable impurities inevitable in manufacturing.
When the metal film 10 has the above-described purity and the second phase particles are less than 100 particles / mm ³ , an anodized film is formed, and when a through-hole called a micropore is formed in the anodized film, It is possible to suppress defects such as disorder of the arrangement.
The purity of aluminum is not particularly limited as long as it is 99.9% by mass or more, and is ideally 100% by mass. If the purity of aluminum is low, the existence probability of grain boundary precipitates or the like that will be the starting point of defects in the through-holes increases, and as a result, defects such as disorder of alignment are induced. For this reason, by increasing the purity, defects such as disorder of the arrangement of micropores can be reduced.
The purity of aluminum can be measured using methods such as ICP (Inductively Coupled Plasma) emission analysis, ICP (Inductively Coupled Plasma) mass spectrometry, and glow discharge mass spectrometry (GD (Glow Discharge) -mass).

The lower limit value of the second phase particles is not particularly limited as long as it is less than 100 particles / mm ³ , and is ideally 0 particles / mm ³ . The inventors have made it clear that the second phase particles have defects in the through-holes starting from this. If the number of second phase particles is large, many of the defects become starting points of defects in the through-holes. As a result, the probability of inducing defects such as disorder of the arrangement of micropores increases. For this reason, by reducing the number of second phase particles, defects such as disorder of the arrangement of micropores can be reduced.
The surface 10a of the metal film 10 preferably has a surface roughness Rt of 0.1 μm or less. When the surface roughness Rt is 0.1 μm or less, when forming a through-hole from the surface of the metal film, it is possible to reduce defects such as disorder of the arrangement of micropores due to the state of the surface of the metal film, The arrangement of micropores in the anodized film is improved. Thereby, the straight pipe property of the through-hole comprised with a micropore improves.
The surface roughness Rt is the maximum cross-sectional height defined by JIS (Japanese Industrial Standards) B 0601-2001.

As shown in FIG. 1, the metal film 10 is disposed on the surface 17 a of the support 17, for example, but may be configured as a single unit without the support 17.
Further, the metal film 10 is not limited to a single layer structure, and may be a multilayer stack structure.
FIG. 2 is a schematic diagram showing a second example of the metal film of the embodiment of the present invention, FIG. 3 is a schematic diagram showing a third example of the metal film of the embodiment of the present invention, and FIG. FIG. 5 is a schematic diagram showing a fourth example of the metal film of the embodiment of the invention, and FIG. 5 is a schematic diagram showing a fifth example of the metal film of the embodiment of the invention.

The metal film 11 shown in FIG. 2 has, for example, a two-layer structure, and includes the first metal layer 12 and the second metal layer 14, and the second metal layer 14 is disposed on the surface 17a of the support body 17. The first metal layer 12 is disposed on the second metal layer 14.
The first metal layer 12 has the same configuration as the metal film 10 described above.
The second metal layer 14 functions as a buffer layer for increasing the thickness of the metal film 11. For example, when the internal stress of the first metal layer 12 is high and the film thickness cannot be increased, by providing the second metal layer 14, the internal stress is relaxed by the second metal layer 14, and the entire metal film 11 is formed. The internal stress can be reduced.
The second metal layer 14 is preferably a valve metal that can be anodized, for example. For example, the second metal layer 14 is made of a valve metal to increase the thickness of the metal film 11. In addition, the entire metal film 11 can be an anodized film.
Examples of the valve metal other than aluminum include tantalum, niobium, titanium, hafnium, zirconium, zinc, magnesium, tungsten, bismuth, and antimony.

The metal film 11 is not limited to the two-layer structure shown in FIG. 2, but may have a three-layer structure shown in FIG. 3 or a five-layer structure shown in FIG.
The metal film 11 shown in FIG. 3 is arranged in the order of the first metal layer 12, the second metal layer 14, and the first metal layer 12 from the support 17 side.
The metal film 11 shown in FIG. 4 includes the first metal layer 12, the second metal layer 14, the first metal layer 12, the second metal layer 14, and the first metal layer 12 from the support 17 side. Arranged in order.
The first metal layer 12 and the second metal layer 14 are alternately arranged, and the first metal layer 12 is arranged as the outermost layer.
Thus, when there are a plurality of first metal layers 12, the first metal layer 12 is disposed on the outermost layer of the metal film 11. The surface 12 a of the first metal layer 12 becomes the surface of the metal film 11. In addition, even in the case of the two-layer structure shown in FIG. 2, the first metal layer 12 is preferably disposed on the outermost layer side when formed on the support 17. In the case of a combination with a metal layer that cannot be anodized, the first metal layer 12 is disposed on the outermost layer side.
In the metal film 11 shown in FIGS. 2 to 4, the surface 12 a of the first metal layer 12 that is the outermost layer preferably has a surface roughness Rt of 0.1 μm or less like the metal film 10 shown in FIG. 1. .

In the case of a two-layer structure, the first metal layer 12 and the dissimilar metal layer 16 may be laminated as shown in FIG. For example, the dissimilar metal layer 16 is provided in the case of the support 17 having no electrical conductivity, and functions as an electrode in the plating process, for example. The dissimilar metal layer 16 is composed of a metal or an alloy, and is composed of a metal having a composition different from that of the first metal layer 12 and the second metal layer 14. The dissimilar metal layer 16 is made of, for example, Cu (copper). For example, the dissimilar metal layer 16 preferably has good bonding properties with the first metal layer 12 or the second metal layer 14.
In addition, the metal with a different composition means that when two compositions are compared, in the case of a single metal, the types of constituent elements are different. In the case of an alloy, when the main components having a content of 50% by mass or more are compared, the types of the main component elements are different.
The metal film 11 shown in FIGS. 2 to 4 can also be configured to dispose the dissimilar metal layer 16 directly on the surface 17 a of the support 17.
The metal film 11 shown in FIGS. 2 to 5 may be in a single state without the support 17 like the metal film 10 shown in FIG. Further, the thickness t of the metal film 11 is the total thickness of the first metal layer 12 and the second metal layer 14. The ratio of the thickness of the second metal layer 14 to the thickness t of the metal film 11 is less than 10%. If the ratio of the thickness of the second metal layer 14 to the thickness t of the metal film 11 is less than 10%, the straight tube ratio of a through hole 21 described later is increased.
The thickness of the second metal layer 14 is the thickness of the second metal layer 14 alone. Even when there are a plurality of second metal layers 14, the thickness of each second metal layer 14 is a single unit.

The support 17 is not particularly limited, and for example, a silicon substrate is used. As the support 17, for example, a ceramic substrate such as SiC, SiN, GaN, and alumina (Al ₂ O ₃ ), a glass substrate, a quartz substrate, a fiber reinforced plastic substrate, and a metal substrate can be used in addition to the silicon substrate. . The fiber reinforced plastic substrate includes an FR-4 (Flame Retardant Type 4) substrate which is a printed wiring board. The support 17 may be a polyimide film having excellent heat resistance, such as Kapton (registered trademark) manufactured by Toray DuPont Co., Ltd.
The support 17 can also be an aluminum substrate or an aluminum alloy substrate having a composition different from that of the metal film 10, that is, the first metal layer 12. In this case, the metal film 11 and the support body 17 including the support body 17 can be made into an anodized film.

(Metal film manufacturing method)
As long as the metal film 10 has the above-described purity and the number of second phase particles is less than 100 particles / mm ³ , the manufacturing method thereof is not particularly limited. The metal film 10 is formed by a film forming process using aluminum having a purity of 99.9% by mass or more and forming a film at a cooling rate of 20 ° C./second or more.
For example, as shown in FIG. 6, the metal film 10 is formed on the surface 17 a of the support body 17.
Examples of a method capable of realizing a cooling rate of 20 ° C./second or more for aluminum having a purity of 99.9% by mass or more include a continuous casting method and a gas phase method. For the vapor phase method, for example, a vapor deposition method, a sputtering method, and an ion plating method can be used.
The metal film 10 preferably has a surface roughness Rt of 0.1 μm or less as described above. For this reason, it is preferable to smooth (planarize) the surface 10a of the metal film 10.
Examples of the smoothing (flattening) method include electrolytic polishing, physical polishing, chemical dissolution, and physical grinding.
Electropolishing is used for mirror finishing of an aluminum material before anodization, and for example, an electropolishing liquid containing phosphoric acid is used.
Physical polishing is, for example, chemical mechanical polishing. Chemical dissolution is, for example, chemical dissolution in a solution containing hydrofluoric acid.
Physical grinding is, for example, a surface planar.
In addition to the above, a gas cluster ion beam (GCIB) can also be used.

Here, FIG. 6 is a schematic view showing an example of the manufacturing method of the first example of the metal film of the embodiment of the present invention. 7 and 8 are schematic views showing an example of the manufacturing method of the second example of the metal film according to the embodiment of the present invention in the order of steps.
In the case of the metal film 11 having a multilayer structure, first, the second metal layer 14 made of, for example, a valve metal is formed on the surface 17 a of the support 17. The method for forming the second metal layer 14 is not particularly limited. When the first metal layer 12 is formed by the vapor phase method, it is preferable that the second metal layer 14 is also formed by the vapor phase method from the viewpoint of the manufacturing process.
Also in the metal film 11, it is preferable that the surface 12a of the outermost first metal layer 12 is smoothed similarly to the metal film 10 so that the surface roughness Rt is 0.1 μm or less.

Next, the structure will be described.
(Structure)
The structure is an anodized film formed using the above-described metal film. It is formed by anodizing the above metal film.
FIG. 9 is a schematic cross-sectional view showing an example of the structure according to the embodiment of the present invention.
The structure 20 shown in FIG. 9 has a through hole 21 that penetrates in the thickness direction Dt. The through hole 21 is called a micropore and has a straight pipe shape. In the structure 20, the straight tube ratio of the through hole 21 is 98% or more.
The straight pipe shape indicates that the axis of the through hole 21 is substantially parallel to the thickness direction Dt of the structure 20 and that the diameter of the through hole 21 is substantially the same in the axial direction. The axis of the through hole 21 being substantially parallel to the thickness direction Dt of the structure 20 means that the angle deviation between the axis of the through hole 21 in the thickness direction Dt and the thickness direction Dt of the structure 20 is 10 °. It is below, it is preferable that it is 5 degrees or less, and it is more preferable that it is 3 degrees or less.
The diameter of the through-hole 21 being substantially the same in the axial direction means that the straight pipe ratio is 98% or more.
It is preferable that the micropores do not have a branch structure from the viewpoint of making the conduction path formed of the conductor a straight pipe structure. The straight pipe ratio is defined by the ratio between the number A of through holes per unit area of the surface 20a of the structure and the number B of through holes per unit area of the back surface 20b. In this case, the ratio of the through hole number A and the through hole number B to the larger numerical value is used. That is, the ratio is obtained by using the larger numerical value as the denominator. For this reason, the straight pipe ratio is a maximum of 100%.
The straight pipe ratio is not particularly limited as long as it is 98% or more, and is ideally 100%.
The structure can be used for capacitors, battery electrodes, gas permeable membranes, sensors, and anisotropic conductive members. By applying a surface modification treatment to the structure, it can be used as a sensor.
The surface of the anodized aluminum structure has high adsorption activity as it is, and the surface is adsorbed with a thiophene derivative as described in WO2009 / 113314 and used as a gas adsorption sensor element or is commercially available from Aldrich. The dye-sensitized solar cell organic dye MK-2 or the like may be adsorbed and used as a member of the dye-sensitized battery. An organic substance may be adsorbed on the surface of the structure through a coating layer having carboxyl or the like. Since the structure in the present invention has very fine pores and a high surface area, it can contribute to improvement in sensitivity when used as a sensor as described above. Further, since it has a high straight pipe property, it is possible to easily remove the adsorbed gas.

[Physical properties and shape of structure]
The structure is made of an anodized film of a metal film, and has, for example, an electrical resistivity (about 10 ¹⁴ Ω · cm) comparable to that of an insulating base material that constitutes a conventionally known anisotropic conductive film or the like.
The thickness ht (see FIG. 9) of the structure 20 is preferably in the range of 1 to 1000 μm, more preferably in the range of 5 to 500 μm, and still more preferably in the range of 10 to 300 μm. . When the thickness of the structure 20 is within this range, the handleability of the structure 20 is improved.
The thickness ht of the structure 20 is obtained by cutting the structure 20 with a focused ion beam (FIB) in the thickness direction Dt and multiplying the cross section by a field emission scanning electron microscope at a magnification of 200,000 times. This is an average value obtained by measuring 10 points in the region corresponding to the thickness ht.

The interval between the through holes in the structure 20 is preferably 5 nm to 800 nm, more preferably 10 nm to 200 nm, and still more preferably 50 nm to 140 nm. When the interval between the through holes in the insulating base is within this range, the structure 20 functions sufficiently as an insulating partition. The interval between the through holes is the same as the interval between the conductors.
Here, the interval between the through holes, that is, the interval between the conductors refers to the width w between adjacent conductors (see FIG. 10), and the cross section of the structure is 200,000 times larger by a field emission scanning electron microscope. The average value observed by magnification and measuring the width between adjacent conductors at 10 points.
In addition, the arrangement of the through holes in the structure is not particularly limited. For example, the through holes may be arranged with a specific period, or the through holes may be arranged with a plurality of periods having different periods. . In this case, for example, the arrangement period of the through holes differs in the thickness direction of the structure 20. When there are two types of arrangement periods of the through holes, for example, the arrangement period of one through hole is 100 nm, the arrangement period of the other through hole is 300 nm, and one through hole and the other through hole are equal to each other. The through holes of the parts overlap.

(Composite material)
Next, the composite material will be described.
The composite material is configured using the above-described structure. The composite material includes a structure and a conductor filled in the through hole of the structure. The composite material is called a metal-filled microstructure, and is used for, for example, an anisotropic conductive member. Hereinafter, the composite material will be described more specifically with reference to FIGS. 10 and 11.
FIG. 10 is a schematic cross-sectional view showing an example of the composite material according to the embodiment of the present invention, and FIG. 11 is a plan view showing an example of the composite material according to the embodiment of the present invention.

As shown in FIG. 10, the composite material 30 penetrates, for example, the structure 20 made of the anodized film of the metal film 10 or the metal film 11 described above and the thickness direction Dt (see FIG. 10) of the structure 20. It is a member provided with the several conductor 32 provided in the state electrically insulated mutually. The composite material 30 further includes a resin layer 34 provided on the front surface 20a and the back surface 20b of the structure 20.
Here, “the state of being electrically insulated from each other” means that the respective conductors existing inside the insulating base material have sufficiently low electrical conductivity between the respective conductors inside the insulating base material. It means a state.
In the composite material 30, the conductors 32 are electrically insulated from each other, and the conductivity is sufficiently low in the direction x orthogonal to the thickness direction Dt (see FIG. 10) of the structure 20, and the thickness direction Dt (FIG. 11). Have a conductive property. Thus, the composite material 30 is a member that exhibits anisotropic conductivity.

As shown in FIG. 10, the conductor 32 is provided through the structure 20 in the thickness direction Dt while being electrically insulated from each other.
Furthermore, as shown in FIG. 10, the conductor 32 may have a protruding portion 32 a and a protruding portion 32 b that protrude from the front surface 20 a and the back surface 20 b of the structure 20. The composite material 30 may further include a resin layer 34 provided on the front surface 20a and the back surface 20b of the structure 20. The resin layer 34 has adhesiveness and imparts bondability. The length of the protruding portion 32a and the protruding portion 32b is preferably 6 nm or more, and more preferably 30 nm to 500 nm.

Further, FIG. 10 shows the structure 20 having the resin layer 34 on the front surface 20a and the back surface 20b. However, the present invention is not limited to this, and the resin layer is formed on at least one surface of the structure 20. 34 may be used.
Similarly, the conductor 32 of FIG. 10 has a protruding portion 32a and a protruding portion 32b at both ends, but is not limited thereto, and has a protruding portion on at least the surface of the structure 20 having the resin layer 34. It may be configured.

The thickness h of the composite material 30 shown in FIG. 10 is, for example, 30 μm or less. The composite material 30 preferably has a total thickness variation (TTV) of 10 μm or less.
Here, the thickness h of the composite material 30 is obtained by observing the composite material 30 with a field emission scanning electron microscope at a magnification of 200,000 times, obtaining the contour shape of the composite material 30, It is the average value measured at 10 points.
Further, TTV (Total Thickness Variation) of the composite material 30 is a value obtained by cutting the composite material 30 by dicing and observing the cross-sectional shape of the composite material 30.

Further, a protective layer (not shown) may be provided on the resin layer 34. Since the protective layer is used to protect the surface of the structure from scratches, an easily peelable tape is preferable. For example, a film with an adhesive layer may be used as the protective layer.
As a film with an adhesive layer, for example, Sanitect (SUNYECT) [registered trademark] (manufactured by Sanei Kaken Co., Ltd.) in which an adhesive layer is formed on the surface of a polyethylene resin film, an adhesive layer is formed on the surface of a polyethylene terephthalate resin film. E-MASK [registered trademark] (manufactured by Nitto Denko Corporation), and MASTAK [registered trademark] (manufactured by Fujimori Kogyo Co., Ltd.) in which an adhesive layer is formed on the polyethylene terephthalate resin film surface. Commercially available products can be used.
Moreover, the method of affixing the film with an adhesion layer is not specifically limited, It can affix using a conventionally well-known surface protection tape sticking apparatus and a laminator.

The composite material 30 may be provided on a support (not shown) for transfer, transportation and transportation, storage, and the like. A release layer (not shown) may be provided between the support and the composite material 30, and the support and the composite material 30 may be separated from each other by the release layer.
As described above, the composite material 30 provided on the support through the release layer is referred to as an anisotropic conductive material.
The support supports the composite material 30 and is made of, for example, a silicon substrate. In addition to the silicon substrate, for example, a ceramic substrate such as SiC, SiN, GaN, and alumina (Al ₂ O ₃ ), a glass substrate, a fiber reinforced plastic substrate, and a metal substrate can be used as the support. The fiber reinforced plastic substrate includes an FR-4 (Flame Retardant Type 4) substrate which is a printed wiring board.

Moreover, as a support body, what has flexibility and is transparent can be used. Examples of the flexible and transparent support include PET (polyethylene terephthalate), polycycloolefin, polycarbonate, acrylic resin, PEN (polyethylene naphthalate), PE (polyethylene), PP (polypropylene), and polystyrene. And plastic films such as polyvinyl chloride, polyvinylidene chloride and TAC (triacetyl cellulose).
Here, the term “transparent” means that the transmittance is 80% or more with light having a wavelength used for alignment. For this reason, although the transmittance | permeability may be low in the visible light whole region of wavelength 400-800 nm, it is preferable that the transmittance | permeability is 80% or more in the visible light whole region of wavelength 400-800 nm. The transmittance is measured with a spectrophotometer.

The release layer is preferably a laminate of a support layer and a release agent. The release agent comes into contact with the composite material 30 and the support and the composite material 30 are separated from the release layer as a starting point. In the anisotropic conductive material, for example, by heating to a predetermined temperature, the adhesive strength of the release agent is weakened, and the support is removed from the composite material 30.
As the release agent, for example, Riva Alpha (registered trademark) manufactured by Nitto Denko Corporation, Somatack (registered trademark) manufactured by Somaru Corporation, and the like can be used.

Hereinafter, the structure and the method for manufacturing the composite material will be described.
(Method for manufacturing structure and composite material)

<First aspect>
FIG. 12 to FIG. 16 are schematic cross-sectional views showing the first aspect of the method for producing a composite material according to the embodiment of the present invention in the order of steps, and collectively show the structure and the method for producing the composite material.
First, as shown in FIG. 12, a metal film 10 is prepared.
The size and thickness of the metal film 10 are appropriately determined according to, for example, the thickness of the structure 20 of the finally obtained composite material 30 (see FIG. 10), that is, the thickness of the insulating base material, the processing apparatus, and the like. It is what is done. The metal film 10 is, for example, a rectangular or wafer-like plate material.

Next, the surface 10a (see FIG. 12) on one side of the metal film 10 is anodized. As a result, the surface 10a (see FIG. 12) on one side of the metal film 10 is anodized and is present at the bottom of the plurality of through holes 21 extending in the thickness direction Dt of the metal film 10, as shown in FIG. An anodic oxide film 24 having a barrier layer 22 is formed. The process of anodizing the metal film 10 is referred to as an anodizing process. In the anodizing treatment step, the anodic oxidation is not limited to one time, and may be performed a plurality of times, and may be performed at least once.
When performing anodization a plurality of times, as a desirable method, after anodizing, a part of the anodized film is dissolved and removed, and then anodized again. Thereby, the arrangement | sequence property of a through-hole can be improved.

In the anodic oxide film 24 having the plurality of through holes 21, the barrier layer 22 exists at the bottom of the through hole 21 as described above, but the barrier layer 22 is removed as shown in FIG. The step of removing the barrier layer 22 is referred to as a barrier layer removing step.
In the barrier layer removing step, by using an alkaline aqueous solution containing ions of the metal M1 having a hydrogen overvoltage higher than that of aluminum, the barrier layer 22 of the anodized film 24 is removed, and at the same time, a metal (metal M1) is formed at the bottom of the through hole 21. A metal layer 25a made of is formed. Thereby, the metal film 10 at the bottom of the through hole 21 is covered with the metal layer 25a.
As shown in FIG. 14, an anodic oxide film 24 having a plurality of through holes 21 is formed as the structure 20. The structure 20 can be formed by the steps shown in FIGS.
In addition, when not using the structure 20 for the composite material 30 (refer FIG. 10), the metal film 10 and the support body 17 are removed, and the structure 20 single-piece | unit shown in FIG. 9 is obtained. By applying various treatments to the structure 20 shown in FIG. 9, it is possible to obtain a product suitable for each application.
As shown in FIGS. 2 to 4, in the case of the metal film 11 having a multilayer structure of the first metal layer 12 and the second metal layer 14, the first metal layer 12 and A through hole 21 is formed in the second metal layer 14. In the case of the metal film 11 having the multilayer structure described above, in the anodizing treatment step, an anodizing treatment corresponding to each of the first metal layer 12 and the second metal layer 14 is performed, and the through hole 21 is formed. . In this case, the anodizing process is performed a number of times corresponding to the number of layers of the metal film 11. The through hole 21 penetrating the first metal layer 12 and the second metal layer 14 may be formed by one anodizing treatment, and the number of anodizing treatments in the anodizing treatment step described above is particularly It is not limited.

In the barrier layer removing process which is a part of the manufacturing process of the structure 20 described above, the barrier layer 22 is removed by using an alkaline aqueous solution containing ions of the metal M1 having a hydrogen overvoltage higher than that of aluminum. In addition, the metal layer 25a of the metal M1, which is less liable to generate hydrogen gas than aluminum, is formed on the metal film 10 exposed at the bottom of the through hole 21. As a result, the in-plane uniformity of metal filling is improved. It is considered that this is because the generation of hydrogen gas by the plating solution is suppressed, and the metal filling by the electrolytic plating easily proceeds.
Further, in the barrier layer removing step, a holding step of holding at a voltage of 95% to 105% of a voltage (holding voltage) selected from a range of less than 30% of the voltage in the anodizing step for a total of 5 minutes or more is provided It has been found that the uniformity of metal filling during plating treatment is greatly improved by combining the application of an alkaline aqueous solution containing ions of the metal M1. For this reason, it is preferable that there is a holding step.
Although the detailed mechanism is unknown, in the barrier layer removal process, a metal M1 layer is formed under the barrier layer by using an alkaline aqueous solution containing ions of the metal M1, thereby damaging the interface between the metal film and the anodic oxide film. This is considered to be because the uniformity of dissolution of the barrier layer was improved.

In the barrier layer removing step, the metal layer 25a made of metal (metal M1) is formed at the bottom of the through hole 21. However, the present invention is not limited to this. The metal film 10 is exposed at the bottom. The metal film 10 may be used as an electrode for electrolytic plating with the metal film 10 exposed.
Moreover, if the support body 17 has electroconductivity, the support body 17 can also be used as an electrode for electrolytic plating.
In the case where the dissimilar metal layer 16 is formed as shown in FIG. 5, the dissimilar metal layer 16 can also be used as an electrode for electrolytic plating.

The subsequent steps are steps for manufacturing the composite material 30.
Next, as shown in FIG. 15, the inside of the through hole 21 of the anodic oxide film 24 shown in FIG. 14 is filled with, for example, a metal 25b as a conductive material. By filling the inside of the through hole 21 with the metal 25b, the conductor 32 having conductivity that functions as a conduction path is formed. In this case, the metal layer 25a made of metal (metal M1) can be used as an electrode for electrolytic plating.
Filling the inside of the through hole 21 with, for example, a metal 25b as a conductive substance is called a metal filling step. Electrolytic plating is used for the metal filling step, and the metal filling step will be described in detail later. The metal layer 25a and the metal 25b are collectively referred to as a metal 25.
After the metal filling step, the metal film 10 and the support 17 are removed as shown in FIG. Thereby, the composite material 30 is obtained. The process of removing the metal film 10 is called a substrate removal process.

<Second aspect>
FIGS. 17-19 is typical sectional drawing which shows the 2nd aspect of the manufacturing method of the composite material of embodiment of this invention to process order.
17 to 19, the same components as those shown in FIGS. 12 to 16 are denoted by the same reference numerals, and detailed description thereof is omitted. FIG. 17 shows a state after FIG. 15 described above.
The second aspect differs from the first aspect described above in the steps shown below. As shown in FIG. 17, after the metal filling process, the surface of the anodic oxide film 24 on the side where the metal film 10 is not provided is partially removed in the thickness direction, and the metal 25 filled in the metal filling process is replaced with the anodic oxide film 24. Project beyond the surface. That is, the conductor 32 is protruded from the surface of the anodic oxide film 24. Protruding the filled metal 25 from the surface of the anodic oxide film 24 is called a surface metal projecting step.
After the surface metal protrusion step, the metal film 10 is removed as shown in FIG. 18 (substrate removal step).

Next, as shown in FIG. 19, the metal 25 filled in the metal filling step is removed by partially removing the surface of the anodic oxide film 24 on the side where the metal film 10 is provided after the substrate removal step, that is, Then, the conductor 32 is protruded from the surface of the anodic oxide film 24. Thereby, the composite material 30 shown in FIG. 19 is obtained.
Although the above-mentioned surface metal protrusion process and the back surface metal protrusion process may be an aspect having both processes, the aspect having one of the front surface metal protrusion process and the back surface metal protrusion process may be employed. The front surface metal protrusion process and the back surface metal protrusion process are collectively referred to as a “metal protrusion process”.

<Third aspect>
20 and 21 are schematic cross-sectional views showing a third aspect of the method for producing a composite material according to the embodiment of the present invention in the order of steps.
20 and 21, the same components as those shown in FIGS. 12 to 16 are denoted by the same reference numerals, and detailed description thereof is omitted. FIG. 20 shows a state after FIG. 15 described above.
The third aspect differs from the first aspect described above in the steps shown below. As shown in FIG. 20, a resin layer 28 is provided on the surface of the anodic oxide film 24 on the side where the metal film 10 is not provided after the metal filling step. Providing the resin layer 28 is called a resin layer forming step.

Next, as shown in FIG. 21, the metal film 10 is removed after the resin layer forming step (substrate removing step). Thereby, the composite material 30 shown in FIG. 16 is obtained.
In the third aspect, the composite material 30 manufactured as shown in FIG. 22 is an aspect intended to be supplied in a state of being wound around the winding core 29 in a roll shape. By peeling off the resin layer 28 (see FIG. 23) when the composite material 30 is used, the composite material 30 can be used as, for example, a metal-filled microstructure or an anisotropic conductive member.

<Other aspects>
As a manufacturing method, for example, the above-described anodizing process, holding process, barrier layer removing process, metal filling process, surface metal projecting process, resin layer forming process, substrate removing process and back surface metal projecting process are performed in this order. Also good.
Alternatively, a part of the surface of the metal film may be anodized using a mask layer having a desired shape.

The smoothing step (flattening step) is not limited to the above-described steps, and for example, the surface 17a of the support 17 may be used as a plane reference for smoothing (flattening) treatment. .
24 to 26 are schematic diagrams illustrating an example of the smoothing process in the order of processes.
As shown in FIG. 24, the metal film 10 is formed on the surface 17 a of the support 17. At this time, the release layer 18 is provided on the surface 17 a of the support 17. As the release layer 18, for example, an oxide film can be used. As the oxide film, an oxide film formed by oxidizing the support 17 can be used as long as the support 17 can be oxidized. For example, when the support 17 is silicon, a silicon oxide film can be formed as an oxide film, and when aluminum is used, an aluminum oxide film can be formed as an oxide film.
As shown in FIG. 25, the metal film 10 is peeled from the peeling layer 18 and separated from the support 17.
Next, as shown in FIG. 26, another support 19 is prepared, and an adhesive layer 19 b is provided on the surface 19 a of the support 19. The metal film 10 is provided with the surface 10a facing the support 19 through the adhesive layer 19b.
The back surface 10 b of the metal film 10 is a surface having smoothness based on the surface 17 a of the support 17. When the smoothing process is performed on the back surface 10b of the metal film 10, since the smoothness is higher than that of the front surface 10a, a predetermined surface roughness Rt can be obtained with a small amount of polishing.
In addition, as an adhesive layer, Q-chuck (trademark) (made by Maruishi Sangyo Co., Ltd.) etc. can be used, for example.
Hereinafter, the structure and the manufacturing method of the composite material will be described more specifically.

[Anodizing treatment process]
In the above-described anodizing treatment step, the surface of one side of the above-described metal film 10 is anodized so that an anodized film having a through hole that exists in the thickness direction and a barrier layer that exists at the bottom of the through hole is formed. It is a process of forming.
A conventionally known method can be used for the anodizing treatment, but from the viewpoint of increasing the regularity of the micropore array and ensuring the anisotropic conductivity of the composite material, a self-regulating method or a constant voltage treatment is used. Is preferred.
Here, as for the self-ordering method and the constant voltage process of the anodizing process, the same processes as those described in paragraphs [0056] to [0108] and [FIG. 3] of Japanese Patent Application Laid-Open No. 2008-270158 are performed. Can be applied.

<Anodizing treatment 1>
The average flow rate of the electrolytic solution in the anodizing treatment is preferably 0.5 to 20.0 m / min, more preferably 1.0 to 15.0 m / min, and 2.0 to 10.0 m / min. More preferably, it is min.
Moreover, the method of flowing the electrolytic solution under the above-mentioned conditions is not particularly limited, but for example, a method using a general stirring device such as a stirrer is used. In particular, it is preferable to use a stirrer that can control the stirring speed by digital display because the average flow velocity can be controlled. Examples of such a stirring apparatus include “Magnetic Stirrer HS-50D (manufactured by AS ONE)” and the like.

For the anodizing treatment, for example, a method in which an aluminum substrate is used as an anode in a solution having an acid concentration of 1 to 10% by mass can be used.
The solution used for the anodizing treatment is preferably an acid solution, sulfuric acid, phosphoric acid, chromic acid, oxalic acid, sulfamic acid, benzenesulfonic acid, amidosulfonic acid, glycolic acid, tartaric acid, malic acid, citric acid. , Malonic acid and the like are more preferable, and sulfuric acid, phosphoric acid and oxalic acid are particularly preferable. These acids can be used alone or in combination of two or more.

The conditions of the anodizing treatment cannot be determined unconditionally because they vary depending on the electrolytic solution used. In general, the electrolytic solution concentration is 0.1 to 20% by mass, the liquid temperature is −10 to 30 ° C., the current is It is preferable that the density is 0.01 to 20 A / dm ² , the voltage is 3 to 300 V, the electrolysis time is 0.5 to 30 hours, the electrolytic solution concentration is 0.5 to 15% by mass, the liquid temperature is −5 to 25 ° C., and the current density. 0.05 to 15 A / dm ² , voltage 5 to 250 V, electrolysis time 1 to 25 hours are more preferable, electrolyte concentration 1 to 10% by mass, solution temperature 0 to 20 ° C., current density 0.1 to 10 A / Dm ² , voltage 10 to 200 V, and electrolysis time 2 to 20 hours are more preferable.

  From the viewpoint of supplying the composite material 30 manufactured according to the above-described third aspect in a shape wound around the winding core 29 (see FIG. 22) having a predetermined diameter and a predetermined width, the above-described anodizing process is performed. The average thickness of the anodized film formed by the above is preferably 30 μm or less, more preferably 5 to 20 μm. The average thickness is determined by cutting the anodic oxide film with a focused ion beam (FIB) in the thickness direction, and a cross-section of the anodic oxide film is a field emission scanning electron microscope (FE-SEM). The surface photograph (magnification 50000 times) was taken and the average value of 10 points was calculated.

<Anodizing treatment 2>
The anodizing treatment is not limited to the above-described anodizing treatment.
As the anodizing treatment, when the film formation rate A ₁ during energization and the film dissolution rate B ₁ during non-energization under direct current constant voltage conditions, the parameter R represented by the following equation is 160 ≦ R By performing the treatment using an electrolytic solution satisfying ≦ 200, preferably 170 ≦ R ≦ 190, particularly preferably 175 ≦ R ≦ 185, the regular arrangement of the through holes can be greatly improved.

R = A ₁ [nm / s] ÷ (B ₁ [nm / s] × applied voltage [V])

The average flow rate of the electrolytic solution in the anodizing treatment is the same as that in the above-described anodizing treatment, and thus it can have uniform and high regularity.
The method of flowing the electrolytic solution under the above-described conditions is the same as the above-described anodizing treatment.
The viscosity of the anodizing solution is preferably 0.0001 to 100.0 Pa · s, more preferably 0.0005 to 80.0 Pa · s at 25 ° C. and 1 atm. By performing the anodic oxidation treatment (d) with the electrolytic solution having a viscosity in the above range, uniform and high regularity can be obtained.

Although both acidic and alkaline can be used for the electrolytic solution used in the anodizing treatment, an acidic electrolytic solution is preferably used from the viewpoint of enhancing the roundness of the holes.
Specifically, hydrochloric acid, sulfuric acid, phosphoric acid, chromic acid, oxalic acid, glycolic acid, tartaric acid, malic acid, citric acid, sulfamic acid, benzenesulfonic acid, amidosulfonic acid, glycolic acid, tartaric acid, malic acid, citric acid , Malonic acid and the like are more preferable, and sulfuric acid, phosphoric acid and oxalic acid are particularly preferable. These acids can be used singly or in combination of two or more, adjusted to the desired parameters from the above formula (ii).

The conditions of the anodic oxidation treatment in the oxide film dissolution treatment 2 can be the same as the above-described anodic oxidation treatment.
The thickness of the anodized film formed by the anodizing treatment is preferably 0.1 to 300 μm, more preferably 0.5 to 150 μm, and still more preferably 1 to 100 μm.
<Oxide film dissolution treatment>
The oxide film dissolution treatment is a treatment (pore diameter enlargement treatment) for enlarging the diameter (pore diameter) of through-holes existing in the anodized film formed by the above-described anodization treatment.

  The oxide film dissolution treatment is performed by bringing the metal film after the anodizing treatment into contact with an acid aqueous solution or an alkali aqueous solution. The method of making it contact is not specifically limited, For example, the immersion method and the spray method are mentioned. Of these, the dipping method is preferred.

When an acid aqueous solution is used in the oxide film dissolution treatment, it is preferable to use an aqueous solution of an inorganic acid such as sulfuric acid, phosphoric acid, nitric acid, hydrochloric acid, or a mixture thereof. Especially, the aqueous solution which does not contain chromic acid is preferable at the point which is excellent in safety | security. The concentration of the acid aqueous solution is preferably 1 to 10% by mass. The temperature of the acid aqueous solution is preferably 25 to 60 ° C.
On the other hand, when an alkaline aqueous solution is used in the oxide film dissolution treatment, it is preferable to use at least one alkaline aqueous solution selected from the group consisting of sodium hydroxide, potassium hydroxide, and lithium hydroxide. The concentration of the alkaline aqueous solution is preferably 0.1 to 5% by mass. The temperature of the alkaline aqueous solution is preferably 20 to 35 ° C.
Specifically, for example, 50 g / L, 40 ° C. phosphoric acid aqueous solution, 0.5 g / L, 30 ° C. sodium hydroxide aqueous solution or 0.5 g / L, 30 ° C. potassium hydroxide aqueous solution is preferably used. .
The immersion time in the acid aqueous solution or alkali aqueous solution is preferably 8 to 120 minutes, more preferably 10 to 90 minutes, and still more preferably 15 to 60 minutes.

In addition, in the oxide film dissolution treatment, the amount of enlargement of the pore diameter varies depending on the conditions of the anodization treatment, but the enlargement ratio before and after the treatment is preferably 1.05 to 100 times, more preferably 1.1 to 75 times, 1.2 to 50 times is particularly preferable.
By the oxide film dissolution treatment, the surface of the anodic oxide film and the inside of the micropore are dissolved, and an anodic oxide film having micropores is obtained on the metal film.

<Anodizing treatment>
It is preferable to perform the above-described anodizing treatment again after the above-described oxide film dissolving treatment.
Through the anodic oxidation process again, the oxidation reaction of the through hole proceeds, and a metal film having an anodic oxide film having micropores deeper than the micropores can be obtained on the metal film.

<Oxide film dissolution treatment>
Further, it is preferable that the above-described oxide film dissolution treatment is further performed after the above-described anodization treatment, the above-described oxide film dissolution treatment, and the above-described anodization treatment are performed in this order.
Since the treatment liquid enters the micropores by this treatment, all the anodic oxide films formed by the anodic oxidation treatment can be dissolved, and the pore diameter of the micropores formed by the anodic oxidation treatment can be increased.
That is, the inside of the micropore on the surface side from the inflection point of the anodic oxide film is dissolved by the oxide film dissolution treatment again, and an anodic oxide film having a straight tubular micropore can be formed on the metal film. .

  Here, the amount of expansion of the pore diameter of the micropore varies depending on the processing conditions of the anodizing treatment, but the expansion ratio before and after the treatment is preferably 1.05 to 100 times, more preferably 1.1 to 75 times, 1.2 to 50 times is particularly preferable.

The cycle of the above-described anodic oxidation treatment and oxide film dissolution treatment is performed one or more times, and the regularity of the arrangement of the through holes becomes higher as the number of repetitions increases.
In addition, by dissolving all of the anodic oxide film formed by the immediately preceding anodic oxidation process by the oxide film dissolution process, the roundness of the micropores viewed from the surface of the film is drastically improved. It is preferable to repeat the process three or more times, more preferably three or more times, and still more preferably four or more times.
In addition, when the above cycle is repeated twice or more, the conditions of each oxide film dissolution treatment and anodization treatment may be the same or different, and the final treatment is anodization treatment. You can finish with.

[Holding process]
The holding step described above is, for example, a voltage of 95% or more and 105% or less of the holding voltage selected from the range of 1 V or more and less than 30% of the voltage in the anodizing treatment step after the anodizing treatment step. This is a step of holding for 5 minutes or more in total. In other words, in the holding step, the voltage is 95% or more and 105% or less of the holding voltage selected from the range of 1 V or more and less than 30% of the voltage in the anodizing treatment step after the anodizing treatment step. In this step, the electrolytic treatment is performed for 5 minutes or more.
Here, the “voltage in the anodizing process” is a voltage applied between the metal film and the counter electrode. For example, if the electrolysis time by the anodizing process is 30 minutes, the voltage maintained for 30 minutes The average value of

  From the viewpoint of controlling the thickness of the barrier layer to an appropriate thickness with respect to the thickness of the side wall of the anodized film, that is, the depth of the through hole, the voltage in the holding process is 5% to 25% of the voltage in the anodizing process. Preferably, it is 5% or more and 20% or less.

Further, for the reason that the in-plane uniformity is further improved, the total holding time in the holding step is preferably 5 minutes or more and 20 minutes or less, more preferably 5 minutes or more and 15 minutes or less, and more preferably 5 minutes or more. More preferably, it is 10 minutes or less.
The holding time in the holding step may be 5 minutes or more in total, but is preferably 5 minutes or more continuously.

  Further, the voltage in the holding process may be set continuously or stepwise (step-like) from the voltage in the anodizing process to the voltage in the holding process, but for the reason that the in-plane uniformity is further improved. The voltage is preferably set to 95% or more and 105% or less of the above holding voltage within 1 second after the end of the anodizing treatment step.

The above-described holding step can be performed continuously with the above-described anodizing treatment step by, for example, lowering the electrolytic potential at the end of the above-described anodizing treatment step.
In the above-described holding step, the same electrolyte solution and processing conditions as those of the above-described conventionally known anodizing treatment can be adopted for conditions other than the electrolytic potential.
In particular, as described above, when the above-described holding step and the above-described anodizing step are continuously performed, it is preferable to perform the treatment using the same electrolytic solution.
The voltage pattern in the holding process after the anodizing process is, for example, a voltage with a voltage drop pattern shown in FIG. 27 and a voltage drop pattern shown in FIG.

[Barrier layer removal process]
The barrier layer removing step is a step of removing the barrier layer of the anodic oxide film using an alkaline aqueous solution containing ions of the metal M1 having a hydrogen overvoltage higher than that of aluminum after the holding step.
Here, the hydrogen overvoltage is a voltage necessary for generating hydrogen. For example, the hydrogen overvoltage of aluminum (Al) is −1.66 V (Journal of the Chemical Society of Japan, 1982, (8). ), P1305-1313). In addition, the example of the metal M1 higher than the hydrogen overvoltage of aluminum and the value of the hydrogen overvoltage are shown below.
<Metal M1 and hydrogen (1N H ₂ SO ₄ ) overvoltage>
Platinum (Pt): 0.00V
・ Gold (Au): 0.02V
Silver (Ag): 0.08V
Nickel (Ni): 0.21V
Copper (Cu): 0.23V
-Tin (Sn): 0.53V
・ Zinc (Zn): 0.70V

In the present invention, it is used in the above-described barrier layer removing step because it causes a substitution reaction with the metal M2 in the metal filling step described later and has less influence on the electrical characteristics of the metal filled in the micropores. The metal M1 is preferably a metal having a higher ionization tendency than the metal M2 used in the metal filling step described later.
Specifically, when copper (Cu) is used as the metal M2 in the metal filling step described later, examples of the metal M1 used in the above-described barrier layer removing step include Zn, Fe, Ni, Sn, and the like. Of these, Zn and Ni are preferably used, and Zn is more preferably used.
Further, when Ni is used as the metal M2 in the metal filling step described later, examples of the metal M1 used in the above-described barrier layer removing step include Zn, Fe, etc. Among them, it is preferable to use Zn.

  A method for removing the barrier layer using such an alkaline aqueous solution containing metal M1 ions is not particularly limited, and examples thereof include a method similar to a conventionally known chemical etching treatment.

<Chemical etching process>
The removal of the barrier layer by chemical etching is performed, for example, by immersing the structure after the above-described anodizing treatment step in an alkaline aqueous solution, filling the inside of the micropore with the alkaline aqueous solution, and then opening the micropores in the anodized film. Only the barrier layer can be selectively dissolved by, for example, a method in which the surface on the part side is brought into contact with a pH (hydrogen ion index) buffer.

Here, it is preferable to use at least one alkaline aqueous solution selected from the group consisting of sodium hydroxide, potassium hydroxide and lithium hydroxide as the alkaline aqueous solution containing the ions of the metal M1. Moreover, it is preferable that the density | concentration of aqueous alkali solution is 0.1-5 mass%. The temperature of the alkaline aqueous solution is preferably 10 to 60 ° C, more preferably 15 to 45 ° C, and further preferably 20 to 35 ° C.
Specifically, for example, 50 g / L, 40 ° C. phosphoric acid aqueous solution, 0.5 g / L, 30 ° C. sodium hydroxide aqueous solution, 0.5 g / L, 30 ° C. potassium hydroxide aqueous solution, etc. are preferably used. It is done.
In addition, as a pH buffer solution, the buffer solution corresponding to the alkaline aqueous solution mentioned above can be used suitably.

  Further, the immersion time in the alkaline aqueous solution is preferably 5 to 120 minutes, more preferably 8 to 120 minutes, still more preferably 8 to 90 minutes, and more preferably 10 to 90 minutes. Particularly preferred. Especially, it is preferable that it is 10 to 60 minutes, and it is more preferable that it is 15 to 60 minutes.

[Other examples of barrier layer removal step]
In addition to the above, the barrier layer removing step may be a step in which the barrier layer of the anodized film is removed and a part of the metal film is exposed at the bottom of the through hole.
In this case, the method for removing the barrier layer is not particularly limited. For example, a method of dissolving the barrier layer electrochemically at a potential lower than the potential in the anodizing treatment in the anodizing treatment step (hereinafter referred to as “electrolytic removal treatment”). A method of removing the barrier layer by etching (hereinafter, also referred to as “etching removal treatment”); a combination of these methods (particularly, after the electrolytic removal treatment is performed, the remaining barrier layer is subjected to the etching removal treatment). And the like).

<Electrolytic removal treatment>
The electrolytic removal treatment is not particularly limited as long as it is an electrolytic treatment performed at a potential lower than the potential (electrolytic potential) in the anodizing treatment in the anodizing treatment step.
The electrolytic dissolution treatment can be performed continuously with the anodizing treatment, for example, by lowering the electrolytic potential at the end of the anodizing treatment step.

The electrolytic removal treatment can employ the same electrolytic solution and treatment conditions as those of the above-described conventionally known anodizing treatment except for the electrolytic potential.
In particular, when the electrolytic removal treatment and the anodic oxidation treatment are successively performed as described above, it is preferable to perform treatment using the same electrolytic solution.

(Electrolytic potential)
The electrolytic potential in the electrolytic removal treatment is preferably lowered continuously or stepwise (stepwise) to a potential lower than the electrolytic potential in the anodic oxidation treatment.
Here, the reduction width (step width) when the electrolytic potential is lowered stepwise is preferably 10 V or less, more preferably 5 V or less, and more preferably 2 V or less from the viewpoint of the withstand voltage of the barrier layer. More preferably it is.
In addition, the voltage drop rate when dropping the electrolytic potential continuously or stepwise is preferably 1 V / second or less, more preferably 0.5 V / second or less, and 0.2 V / second from the viewpoint of productivity. More preferred is less than a second.

<Etching removal treatment>
The etching removal process is not particularly limited, but may be a chemical etching process that dissolves using an acid aqueous solution or an alkali aqueous solution, or may be a dry etching process.

(Chemical etching process)
The removal of the barrier layer by the chemical etching treatment is performed, for example, by immersing the structure after the anodizing treatment step in an acid aqueous solution or an alkali aqueous solution, filling the inside of the micropore with an acid aqueous solution or an alkali aqueous solution, and then removing the anodized film. For example, the surface of the micropore opening side is brought into contact with a pH (hydrogen ion index) buffer solution, and only the barrier layer can be selectively dissolved.

Here, when an acid aqueous solution is used, it is preferable to use an aqueous solution of an inorganic acid such as sulfuric acid, phosphoric acid, nitric acid, hydrochloric acid, or a mixture thereof. The concentration of the acid aqueous solution is preferably 1% by mass to 10% by mass. The temperature of the acid aqueous solution is preferably 15 ° C to 80 ° C, more preferably 20 ° C to 60 ° C, and further preferably 30 ° C to 50 ° C.
On the other hand, when using an alkaline aqueous solution, it is preferable to use an aqueous solution of at least one alkali selected from the group consisting of sodium hydroxide, potassium hydroxide and lithium hydroxide. Moreover, it is preferable that the density | concentration of aqueous alkali solution is 0.1 mass%-5 mass%. The temperature of the alkaline aqueous solution is preferably 10 ° C to 60 ° C, more preferably 15 ° C to 45 ° C, and further preferably 20 ° C to 35 ° C. The alkaline aqueous solution may contain zinc and other metals.
Specifically, for example, 50 g / L, 40 ° C. phosphoric acid aqueous solution, 0.5 g / L, 30 ° C. sodium hydroxide aqueous solution, 0.5 g / L, 30 ° C. potassium hydroxide aqueous solution, etc. are preferably used. It is done.
In addition, as a pH buffer solution, the buffer solution corresponding to the acid aqueous solution or alkali aqueous solution mentioned above can be used suitably.

  The immersion time in the acid aqueous solution or alkaline aqueous solution is preferably 8 minutes to 120 minutes, more preferably 10 minutes to 90 minutes, and further preferably 15 minutes to 60 minutes.

(Dry etching process)
For the dry etching treatment, for example, a gas species such as a Cl ₂ / Ar mixed gas is preferably used.

[Metal filling process]
The metal filling step is a step of filling the inside of the through hole in the anodic oxide film with, for example, a metal M2 as a conductive substance using electrolytic plating after the above-described barrier layer removing step.

<Metal M2>
The metal M2 is preferably a material having an electrical resistivity of 10 ³ Ω · cm or less, and specific examples thereof include gold (Au), silver (Ag), copper (Cu), aluminum (Al), Suitable examples include magnesium (Mg), nickel (Ni), zinc (Zn), and the like.
Among these, from the viewpoint of electrical conductivity, Cu, Au, Al, and Ni are preferable, Cu and Au are more preferable, and Cu is more preferable.
In addition, although the metal is filled in the metal filling step, the conductor 32 is not limited to the metal, and any conductive material may be used. Instead of metal, tin oxide (ITO) doped with indium may be filled.

<Metal filling method>
For example, an electrolytic plating method or an electroless plating method can be used as a plating method for filling the inside of the micropores with the metal M2.
Here, in the conventionally known electroplating method used for coloring or the like, it is difficult to selectively deposit (grow) a metal in a hole at a high aspect. This is presumably because the deposited metal is consumed in the holes and the plating does not grow even if electrolysis is performed for a certain period of time.

For this reason, in the production method of the present invention, when a metal is filled by an electrolytic plating method, it is necessary to provide a downtime during pulse electrolysis or constant potential electrolysis. The pause time is required to be 10 seconds or longer, and is preferably 30 to 60 seconds.
It is also desirable to add ultrasonic waves to promote stirring of the electrolyte.
Furthermore, the electrolysis voltage is usually 20 V or less, preferably 10 V or less, but it is preferable to measure the deposition potential of the target metal in the electrolytic solution to be used in advance and perform constant potential electrolysis within the potential of +1 V. In addition, when performing constant potential electrolysis, what can use cyclic voltammetry together is desirable, and potentiostat apparatuses, such as Solartron, BAS, Hokuto Denko, IVIUM, etc., can be used.

A conventionally well-known plating solution can be used for a plating solution.
Specifically, when copper is precipitated, an aqueous copper sulfate solution is generally used, but the concentration of copper sulfate is preferably 1 to 300 g / L, more preferably 100 to 200 g / L. preferable. Moreover, precipitation can be promoted by adding hydrochloric acid to the electrolytic solution. In this case, the hydrochloric acid concentration is preferably 10 to 20 g / L.
In addition, when gold is deposited, it is desirable to perform plating by alternating current electrolysis using a sulfuric acid solution of tetrachlorogold.

  In addition, in the electroless plating method, it takes a long time to completely fill a metal made of a through hole having a high aspect ratio. Therefore, in the manufacturing method of the present invention, it is desirable to fill the metal by an electrolytic plating method. .

  In the present invention, the barrier layer is removed by the above-described barrier layer removing step, and the metal layer made of the above-described metal M1 is formed at the bottom of the through hole. Generation | occurrence | production was suppressed and it is thought that the metal filling by a plating process progressed easily.

[Substrate removal process]
The above-described substrate removal step is a step of removing the metal film and obtaining a composite material after the metal filling step.
The method for removing the metal film is not particularly limited, and for example, a method for removing the metal film by dissolution is preferable.

<Dissolution of metal film>
For the dissolution of the metal film described above, it is preferable to use a treatment liquid that hardly dissolves the anodized film and easily dissolves the aluminum constituting the metal film.
Such a treatment liquid preferably has a dissolution rate with respect to aluminum of 1 μm / min or more, more preferably 3 μm / min or more, and further preferably 5 μm / min or more. Similarly, the dissolution rate for the anodic oxide film is preferably 0.1 nm / min or less, more preferably 0.05 nm / min or less, and still more preferably 0.01 nm / min or less.
Specifically, the treatment liquid preferably contains at least one metal compound having a lower ionization tendency than aluminum and has a pH of 4 or less or 8 or more, and the pH is 3 or less or 9 or more. Is more preferably 2 or less or 10 or more.

Such a treatment liquid is based on an acid or alkaline aqueous solution, for example, manganese, zinc, chromium, iron, cadmium, cobalt, nickel, tin, lead, antimony, bismuth, copper, mercury, silver, palladium, platinum, A gold compound (for example, chloroplatinic acid), a fluoride thereof, a chloride thereof, or the like is preferably used.
Among them, an acid aqueous solution base is preferable, and it is preferable to blend a chloride.
In particular, a treatment liquid (hydrochloric acid / mercury chloride) in which mercury chloride is blended with an aqueous hydrochloric acid solution and a treatment liquid (hydrochloric acid / copper chloride) in which copper chloride is blended with an aqueous hydrochloric acid solution are preferable from the viewpoint of treatment latitude.
The composition of such a treatment liquid is not particularly limited, and for example, a bromine / methanol mixture, a bromine / ethanol mixture, aqua regia and the like can be used.

Moreover, 0.01-10 mol / L is preferable and, as for the acid or alkali concentration of such a processing liquid, 0.05-5 mol / L is more preferable.
Furthermore, the treatment temperature using such a treatment liquid is preferably −10 ° C. to 80 ° C., and preferably 0 ° C. to 60 ° C.

  Further, the dissolution of the metal film is performed by bringing the metal film after the metal filling step into contact with the treatment liquid. The method of making it contact is not specifically limited, For example, the immersion method and the spray method are mentioned. Of these, the dipping method is preferred. The contact time at this time is preferably 10 seconds to 5 hours, and more preferably 1 minute to 3 hours.

[Metal protrusion process]
In the manufacturing method of the present invention, for the reason that the metal bondability of the composite material to be produced is improved, as shown in the second aspect described above, it has a front surface metal protrusion step and / or a rear surface metal protrusion step. preferable.
Here, the surface metal protrusion process is a part of the surface of the anodic oxide film that is not the metal film in the thickness direction after the metal filling process and before the substrate removing process. In this step, the metal M2 removed and filled in the metal filling step is protruded from the surface of the anodic oxide film.
In addition, the back surface metal protrusion process is a process in which a part of the surface of the above anodic oxide film on which the above metal film is provided is removed in the thickness direction after the above substrate removal process, and the above metal filling process. In this step, the filled metal M2 is projected from the surface of the anodic oxide film.

  Such partial removal of the anodic oxide film in the metal projecting step is, for example, an acid aqueous solution or an alkali aqueous solution that does not dissolve the metal M1 and metal M2, particularly the metal M2, but dissolves the anodic oxide film, that is, aluminum oxide. On the other hand, it can be performed by contacting an anodic oxide film having a through hole filled with metal. The method of making it contact is not specifically limited, For example, the immersion method and the spray method are mentioned. Of these, the dipping method is preferred.

In the case of using an acid aqueous solution, it is preferable to use an aqueous solution of an inorganic acid such as sulfuric acid, phosphoric acid, nitric acid, hydrochloric acid or a mixture thereof. Especially, the aqueous solution which does not contain chromic acid is preferable at the point which is excellent in safety | security. The concentration of the acid aqueous solution is preferably 1 to 10% by mass. The temperature of the acid aqueous solution is preferably 25 to 60 ° C.
Moreover, when using alkaline aqueous solution, it is preferable to use the aqueous solution of the at least 1 alkali selected from the group which consists of sodium hydroxide, potassium hydroxide, and lithium hydroxide. The concentration of the alkaline aqueous solution is preferably 0.1 to 5% by mass. The temperature of the alkaline aqueous solution is preferably 20 to 35 ° C.
Specifically, for example, 50 g / L, 40 ° C. phosphoric acid aqueous solution, 0.5 g / L, 30 ° C. sodium hydroxide aqueous solution or 0.5 g / L, 30 ° C. potassium hydroxide aqueous solution is preferably used. .
The immersion time in the acid aqueous solution or alkali aqueous solution is preferably 8 to 120 minutes, more preferably 10 to 90 minutes, and still more preferably 15 to 60 minutes. Here, the immersion time means the total of each immersion time when a short immersion treatment is repeated. In addition, you may perform a washing process between each immersion process.

  Further, in the manufacturing method of the present invention, when the composite material to be produced is used as an anisotropic conductive member, the above-mentioned surface metal protrusion is used because the pressure bonding property with an adherend such as a wiring board becomes good. The step and / or the above-described back surface metal protrusion step is preferably a step of causing the above-described metal M2 to protrude from the surface of the above-described anodized film by 10 to 1000 nm, and more preferably a step of protruding from 50 to 500 nm. .

  Furthermore, in the production method of the present invention, when the produced composite material and the electrode are connected (joined) by a technique such as pressure bonding, the insulation in the surface direction can be sufficiently secured when the protruding portion is crushed. From the above, it is preferable that the aspect ratio (height of the protruding portion / diameter of the protruding portion) of the protruding portion formed by the above-described front surface metal protruding step and / or the above-described back surface metal protruding step is 0.01 or more and less than 20. 6 to 20 is preferable.

In addition, it is preferable that the conductor 32 (refer FIG. 10) which comprises the above-mentioned conduction path is columnar, and it is preferable that the diameter d (refer FIG. 10) is more than 5 nm and 10 micrometers or less, and is 40 nm-1000 nm. More preferably.
In addition, the conductors 32 constituting the above-described conduction path are present in a state where they are insulated from each other by an anodized film of a metal film, and the density is preferably 20,000 pieces / mm 2 or more, It is more preferably ² million pieces / mm ² or more, more preferably 10 million pieces / mm ² or more, particularly preferably 50 million pieces / mm ² or more, and 100 million pieces / mm ² or more. Most preferably.
Furthermore, the center-to-center distance p between adjacent conductors (see FIG. 10) is preferably 20 nm to 500 nm, more preferably 40 nm to 200 nm, and even more preferably 50 nm to 140 nm.

[Resin layer forming step]
In the manufacturing method of this invention, it is preferable to have a resin layer formation process as shown to the 3rd aspect mentioned above from the reason which the conveyance property of the composite material produced improves.
Here, the resin layer forming step is after the above-described metal filling step (after the above-mentioned surface metal protruding step if it has the above-mentioned surface metal protruding step) and before the above-described substrate removing step, This is a step of providing a resin layer on the surface of the above-described anodic oxide film on which the above-described metal film is not provided.

  Specific examples of the resin material constituting the resin layer include an ethylene copolymer, a polyamide resin, a polyester resin, a polyurethane resin, a polyolefin resin, an acrylic resin, and a cellulose resin. However, from the viewpoint of transportability and ease of use as an anisotropic conductive member, the above resin layer is preferably a peelable film with an adhesive layer, and is adhesive by heat treatment or ultraviolet exposure treatment. It is more preferable that the film has a pressure-sensitive adhesive layer that becomes weak and peelable.

The above-mentioned film with an adhesive layer is not particularly limited, and examples thereof include a heat release resin layer and an ultraviolet (UV) release resin layer.
Here, the heat-peelable resin layer has adhesive strength at room temperature and can be easily peeled off only by heating, and many of them use mainly foamable microcapsules.
Specific examples of the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer include a rubber-based pressure-sensitive adhesive, an acrylic pressure-sensitive adhesive, a vinyl alkyl ether-based pressure-sensitive adhesive, a silicone-based pressure-sensitive adhesive, a polyester-based pressure-sensitive adhesive, and a polyamide-based pressure-sensitive adhesive. , Urethane adhesives, styrene-diene block copolymer adhesives, and the like.
Further, the UV peelable resin layer has a UV curable adhesive layer, and loses the adhesive force upon curing and can be peeled off.
Examples of the UV curable adhesive layer include a polymer in which a carbon-carbon double bond is introduced into the polymer side chain, main chain, or main chain terminal in the base polymer. As the base polymer having a carbon-carbon double bond, those having an acrylic polymer as a basic skeleton are preferable.
Furthermore, since the acrylic polymer is crosslinked, a polyfunctional monomer or the like can be included as a monomer component for copolymerization, if necessary.
The base polymer having a carbon-carbon double bond can be used alone, but a UV curable monomer or oligomer can also be blended.
The UV curable adhesive layer is preferably used in combination with a photopolymerization initiator in order to be cured by UV irradiation. Photopolymerization initiators include benzoin ether compounds; ketal compounds; aromatic sulfonyl chloride compounds; photoactive oxime compounds; benzophenone compounds; thioxanthone compounds; camphorquinones; halogenated ketones; Phosphonate etc. are mentioned.

  Commercially available products of the heat-peelable resin layer include, for example, Intellimer [registered trademark] tape (manufactured by Nitta Co., Ltd.) such as WS5130C02 and WS5130C10; 3198, no. 3198LS, no. 3198M, no. 3198MS, no. 3198H, no. 3195, no. 3196, no. 3195M, no. 3195MS, no. 3195H, no. 3195HS, no. 3195V, no. 3195VS, no. 319Y-4L, no. 319Y-4LS, no. 319Y-4M, no. 319Y-4MS, no. 319Y-4H, no. 319Y-4HS, no. 319Y-4LSC, no. 31935MS, no. 31935HS, no. 3193M, no. Ribaalpha [registered trademark] series (manufactured by Nitto Denko Corporation) such as 3193MS;

Examples of commercially available UV peelable resin layers include ELP DU-300, ELP DU-2385KS, ELP DU-2187G, ELP NBD-3190K, ELP UE-2091J and other ELEP holders (registered trademark) (Nitto Denko). Manufactured by); Adwill D-210, Adwill D-203, Adwill D-202, Adwill D-175, Adwill D-675 (all manufactured by Lintec Co., Ltd.); Sumitite [registered trademark] FLS N8000 series (Sumitomo Bakelite) UC353EP-110 (Furukawa Electric Co., Ltd.);
ELP RF-7232DB, ELP UB-5133D (all manufactured by Nitto Denko Corporation); SP-575B-150, SP-541B-205, SP-537T-160, SP-537T-230 (all Furukawa Electric Co., Ltd.) Etc.) can be used.

  Moreover, the method of affixing the above-mentioned film with an adhesion layer is not specifically limited, It can affix using a conventionally well-known surface protection tape sticking apparatus and a laminator.

[Winding process]
Since the transportability of the composite material to be produced is further improved, it has a winding step of winding the composite material in a roll shape with the above-described resin layer after the optional resin layer forming step. Is preferred.
Here, the winding method in the above-described winding step is not particularly limited, and examples thereof include a method of winding around a winding core 29 having a predetermined diameter and a predetermined width as shown in FIG.

  Moreover, in the manufacturing method of this invention, it is preferable that the average thickness of the composite material except a resin layer is 30 micrometers or less from a viewpoint of the ease of winding in the above-mentioned winding process, and it is 5-20 micrometers more. preferable. The average thickness is the average value obtained by cutting the composite material excluding the resin layer with FIB in the thickness direction, taking a cross-sectional photograph of the surface with FE-SEM (50000 times magnification), and measuring 10 points. Calculated.

[Other processing steps]
In addition to the steps described above, the production method of the present invention includes a polishing step, a surface smoothing step, and a protective film formation described in paragraphs [0049] to [0057] of Patent Document 1 (International Publication No. 2015/029881). You may have a process and a water washing process.
In addition, from the viewpoint of handling in manufacturing and using a composite material as an anisotropic conductive member, various processes and formats as shown below can be applied.

<Example of process using temporary adhesive>
In the present invention, after the composite material is obtained by the above-described substrate removal step, the composite material is fixed on a silicon wafer using a temporary adhesive (Temporary Bonding Materials) and thinned by polishing. May be.
Next, after the thinning step, the surface metal protrusion step described above can be performed after the surface is sufficiently washed.
Next, after applying a temporary adhesive having a stronger adhesive strength to the surface from which the metal is protruded and fixing it onto the silicon wafer, the silicon wafer that had been bonded with the previous temporary adhesive is peeled off. And the above-mentioned back surface metal protrusion process can be performed with respect to the surface of the peeled composite material side.

<Example of process using wax>
In this invention, after obtaining a composite material by the above-mentioned board | substrate removal process, you may have the process of fixing a composite material on a silicon wafer using a wax, and thinning by grinding | polishing.
Next, after the thinning step, the surface metal protrusion step described above can be performed after the surface is sufficiently washed.
Next, a temporary adhesive is applied to the surface from which the metal is protruded and fixed on the silicon wafer, and then the wax is dissolved by heating to peel off the silicon wafer. The above-mentioned back surface metal protrusion process can be performed.
Although solid wax may be used, the use of liquid wax such as Skycoat (manufactured by Nikka Seiko Co., Ltd.) can improve the coating thickness uniformity.

<Example of a process for performing substrate removal processing later>
In the present invention, after the metal filling step and before the substrate removing step, the metal film is made of a rigid substrate (for example, silicon wafer, glass substrate) using a temporary adhesive, wax or a functional adsorption film. Etc.), the surface of the above-described anodic oxide film on which the above-mentioned metal film is not provided may be thinned by polishing.
Next, after the thinning step, the surface metal protrusion step described above can be performed after the surface is sufficiently washed.
Next, after applying a resin material (eg, epoxy resin, polyimide resin, etc.) that is an insulating material to the surface from which the metal is projected, a rigid substrate can be attached to the surface by the same method as described above. . For the pasting with the resin material, select the one whose adhesive strength is greater than the adhesive strength with the temporary adhesive, etc., and after pasting with the resin material, the first rigid substrate is peeled off, and the above-mentioned substrate A removal process, a polishing process, and a back surface metal protrusion treatment process can be sequentially performed.
In addition, as a functional adsorption film, Q-chuck (trademark) (made by Maruishi Sangyo Co., Ltd.) etc. can be used.

The composite material is preferably provided as a product in a state where the composite material is attached to a rigid substrate (for example, a silicon wafer, a glass substrate, or the like) by a peelable layer.
In such a supply form, when the composite material is used as a joining member, the surface of the composite material is temporarily bonded to the device surface, and the device to be connected is installed in an appropriate place after the rigid substrate is peeled off. The upper and lower devices can be joined by a composite material by thermocompression bonding.
Further, as the peelable layer, a heat peeling layer may be used, or a photo peeling layer may be used in combination with a glass substrate.

Moreover, each process mentioned above can also perform each process by a sheet | seat, and can also carry out a continuous process with a web by using the coil of a metal film as an original fabric.
Moreover, when performing a continuous process, it is preferable to install an appropriate washing | cleaning process and drying process between each process.

Hereinafter, a semiconductor package using the composite material 30 (see FIG. 10 and the like) will be described.
(Semiconductor package)
[Semiconductor package manufacturing method 1]
For example, after the above [metal filling step], a semiconductor element mounting step for mounting a semiconductor element on the surface of the above-mentioned composite material and bonding the above-mentioned metal M2 and the electrode of the semiconductor element, and a molding step for molding with resin Then, the semiconductor package 40 shown in FIG. 29 can be manufactured by the manufacturing method having the above-mentioned [substrate removing step] in this order.
FIG. 29 is a schematic cross-sectional view showing a first example of a semiconductor package. 29 to 37 shown below, the same components as those of the composite material 30 shown in FIG. 10 described above are denoted by the same reference numerals, and detailed description thereof is omitted.
In the semiconductor package 40 shown in FIG. 29, the semiconductor element 42 is placed on the surface 30 a of the composite material 30 and is electrically connected to the composite material 30 by the solder balls 45. The surface 30 a of the composite material 30 is covered with a mold resin 44 including the semiconductor element 42.

[Semiconductor element mounting process]
When a semiconductor element is mounted on the composite material of the present invention, it is accompanied by mounting by heating. However, in the mounting by thermocompression including solder reflow and the mounting by flip chip, the highest level is achieved from the viewpoint of uniform and reliable mounting. The temperature is preferably 220 to 350 ° C, more preferably 240 to 320 ° C, and particularly preferably 260 to 300 ° C.
The time for maintaining these maximum temperatures is preferably from 2 seconds to 10 minutes, more preferably from 5 seconds to 5 minutes, and particularly preferably from 10 seconds to 3 minutes.
Further, from the viewpoint of suppressing cracks generated in the anodic oxide film due to the difference in thermal expansion coefficient between the aluminum substrate and the anodic oxide film, the desired constant temperature is reached for 5 seconds before the above-mentioned maximum temperature is reached. A method of performing a heat treatment for 10 minutes to 10 minutes, more preferably 10 seconds to 5 minutes, and particularly preferably 20 seconds to 3 minutes can be used. The desired constant temperature is preferably 80 to 200 ° C, more preferably 100 to 180 ° C, and particularly preferably 120 to 160 ° C.
Moreover, as temperature at the time of mounting by wire bonding, from a viewpoint of performing reliable mounting, 80-300 degreeC is preferable, 90-250 degreeC is more preferable, and 100-200 degreeC is especially preferable. The heating time is preferably 2 seconds to 10 minutes, more preferably 5 seconds to 5 minutes, and particularly preferably 10 seconds to 3 minutes.

[Semiconductor package manufacturing method 2]
After the above [metal filling step], an element mounting step for mounting a semiconductor element with a resin paste in which solder or silver paste or a filler is filled on the surface of the composite material, a molding step for molding with resin, Forming a hole in the mold resin to expose the element electrode and the metal M2, a wiring forming process for electrically connecting the metal M2 and the electrode of the semiconductor element, and an insulating layer covering the wiring The semiconductor package 40 shown in FIG. 30 can be manufactured by the manufacturing method which has the insulating layer formation process to form and the above-mentioned [substrate removal process] in this order.
FIG. 30 is a schematic cross-sectional view showing a second example of a semiconductor package.
In the semiconductor package 40 shown in FIG. 30, a semiconductor element 42 is placed on the surface 30a of the composite material 30 and electrically connected thereto. The surface 30 a of the composite material 30 is covered with a mold resin 44 including the semiconductor element 42. A hole 46 is formed in the mold resin 44 for forming a wiring that electrically connects the electrode of the semiconductor element 42 and the conductor 32 of the composite material 30. A wiring 47 passing through the hole 46 is provided. The wiring 47 electrically connects the electrode of the semiconductor element 42 and the metal M2 of the composite material 30. An insulating layer 48 that covers the wiring 47 is provided on the upper surface of the mold resin 44.

<Wiring formation process>
The above-described wiring forming step is a step of forming a wiring on at least one surface of the above-described composite material.
Here, examples of the method for forming the wiring include a method of performing various plating processes such as an electrolytic plating process, an electroless plating process, and a displacement plating process; a sputtering process; a vapor deposition process; Among these, from the viewpoint of high heat resistance, it is preferable to form a layer only of metal, and from the viewpoint of thick film, uniform formation and high adhesion, layer formation by plating is particularly preferable. Since the plating process described above is a plating process for a non-conductive substance (composite material), a method of forming a thick metal layer using the metal layer after providing a reduced metal layer called a seed layer is used. Is preferred.
The above seed layer is preferably formed by a sputtering process. In addition, electroless plating may be used for the formation of the seed layer, and examples of the plating solution include main components such as metal salts and reducing agents, and pH adjusting agents, buffering agents, and complexing agents. It is preferable to use a solution composed of auxiliary components such as accelerators, stabilizers and improvers.
In addition, as a plating solution, SE-650 * 666 * 680, SEK-670 * 797, SFK-63 (all manufactured by Nippon Kanisen Co., Ltd.), Melplate NI-4128, Enplate NI-433, Enplate NI-411 Commercial products such as those manufactured by Meltex can be used as appropriate.
In addition, when copper is used as the wiring material described above, various electrolytic solutions containing sulfuric acid, copper sulfate, hydrochloric acid, polyethylene glycol, and a surfactant as main components and various other additives can be used.

The wiring formed in this way is patterned by a known method according to the mounting design of a semiconductor element or the like. Further, a metal including solder is again provided at a place where a semiconductor element or the like is actually mounted, and can be appropriately processed so as to be easily connected by thermocompression bonding, flip chip, wire bonding, or the like.
As a suitable metal, a metal material such as solder or gold (Au), silver (Ag), copper (Cu), aluminum (Al), magnesium (Mg), nickel (Ni) is preferable. From the viewpoint of mounting reliability, a method of providing Au or Ag via solder or Ni is preferable from the viewpoint of connection reliability.
Specifically, as a method of forming gold (Au) via nickel (Ni) on a copper (Cu) wiring on which a pattern is formed, Ni strike plating is performed, and then Au plating is performed. Can be mentioned.
Here, the Ni strike plating is performed for the purpose of removing the surface oxide layer of the Cu wiring and ensuring the adhesion of the Au layer.
For Ni strike plating, a general Ni / hydrochloric acid mixed solution may be used, or a commercially available product such as NIPS-100 (manufactured by Hitachi Chemical Co., Ltd.) may be used.
On the other hand, Au plating is performed for the purpose of improving wire bonding or solder wettability after performing Ni strike plating. The Au plating is preferably generated by electroless plating, such as HGS-5400 (manufactured by Hitachi Chemical Co., Ltd.), microfab Au series, galvanomister GB series, precious hub IG series (all manufactured by Tanaka Kikinzoku). A commercially available processing solution can be used.

  In addition, as an aspect of connecting the composite material of the present invention and the semiconductor element or the like using the above-described wiring, for example, flip chip connection using C4 (Controlled Collapse Chip Connection) bumps, solder balls, Cu pillars, and the like, and Examples include connection using a conductive particle array type anisotropic conductive film (ACF), but the embodiment of the present invention is not limited thereto.

[Coaxial structure]
In addition, for example, as shown in FIG. 37 and FIG. 38, the above-described wiring is connected to the ground wiring 103 at a predetermined interval around the plurality of linear conductors 100 through which the signal current flows. A shaped conductor 100 can also be disposed. Since this structure is equivalent to a coaxial line, a shielding (shielding) effect can be achieved. Further, a plurality of linear conductors 100 connected to the ground wiring 103 are arranged between the plurality of linear conductors 100 that are arranged adjacent to each other and through which different signal currents flow. For this reason, it is possible to reduce electrical coupling (capacitive coupling) between the plurality of linear conductors 100 that are arranged adjacent to each other and through which different signal currents flow. It can suppress becoming a source. In FIG. 37, a plurality of linear conductors 100 through which a signal current flows are formed on an insulating substrate 101, are electrically insulated from each other, and are electrically connected to a signal wiring 102. Each of the signal wiring 102 and the ground wiring 103 is electrically connected to a wiring layer 105 that is electrically insulated by an insulating layer 104.

<Insulating layer formation process>
The above insulating layer forming step is a step of forming the above insulating layer.
The method for forming the insulating layer is not particularly limited. However, when the resin described later is used as the insulating layer, for example, a method of laminating the above composite material using a laminator device, a spin coater device is used. Examples thereof include a method of coating on the above-described composite material, and a method of forming an insulating layer simultaneously with the bonding of the above-described composite material and the above-described semiconductor element using a flip chip bonding apparatus.

(Insulating layer)
The material of the insulating layer is not particularly limited as long as it is a highly insulating material, and specific examples thereof include inorganic insulators such as air, glass and alumina, organic insulators such as resins, and the like. These may be used alone or in combination of two or more. Among these, it is preferable to use a resin because it is inexpensive and has high thermal conductivity.

The material of the above resin is preferably a thermosetting resin. The thermosetting resin is preferably at least one selected from the group consisting of epoxy resins, modified epoxy resins, silicone resins, modified silicone resins, acrylate resins, urethane resins, and polyimide resins. Epoxy resins, silicone resins, and modified silicone resins are more preferable.
Moreover, it is preferable to use resin excellent in heat resistance, a weather resistance, and light resistance as said resin.
Moreover, in order to give the above-mentioned resin a predetermined function, at least one selected from the group consisting of a filler, a diffusing agent, a pigment, a fluorescent material, a reflective material, an ultraviolet absorber, and an antioxidant is used. It can also be mixed.
Moreover, an adhesive composition can also be used as the above-mentioned resin, for example, commonly referred to as underfill material (liquid), NCP (Non Conductive Paste) (paste form), NCF (Non Conductive Film) (film form) For example, a dry film resist can be used.
Furthermore, as the above-mentioned insulating layer, a conductive particle array type anisotropic conductive film (ACF) described also as the above-mentioned wiring may be used.
However, in the present invention, the above-described insulating layer is not limited to the above-described embodiment.

<Drilling process>
The drilling process may be a physical method such as laser processing, drilling, or dry etching, or a chemical method using wet etching, but is not limited to these methods.

[Semiconductor Package Manufacturing Method 3]
A mask layer is formed on the surface of the composite material between the metal filling step and the semiconductor element mounting step or the semiconductor element mounting step described in the semiconductor package manufacturing method 1 and the semiconductor package manufacturing method 2 described above. The manufacturing method which has the mask layer formation process to form, the above-mentioned metal M2 with which the above-mentioned anodic oxide film was filled, the filling metal removal process which removes metal M1, and the mask layer removal process which removes the above-mentioned mask layer in this order Thus, the semiconductor package 40 shown in FIG. 31 can be manufactured.
FIG. 31 is a schematic cross-sectional view showing a third example of a semiconductor package.
The semiconductor package 40 shown in FIG. 31 has the same configuration except that the configuration of the composite material 30 is different from that of the semiconductor package 40 shown in FIG. In the composite material 30, the resin 49 is filled in the portion where the metal M <b> 2 and the metal M <b> 1 are removed by the filling metal removal step. The composite material 30 and the semiconductor element 42 are electrically connected by solder balls 45 provided on the conductor 32 that is not removed.

[Semiconductor Package Manufacturing Method 4]
A mask layer is formed on the surface of the above-mentioned composite material between the above-described metal filling step described in the semiconductor package manufacturing method 1 and the semiconductor package 2 and the above-described semiconductor element mounting step or the semiconductor element mounting step. A mask layer forming step, a composite material removing step for removing the above-described composite material, a resin filling step for filling the resin from which the composite material has been removed, and a mask layer removing step for removing the above-mentioned mask layer The semiconductor package 40 shown in FIG. 32 can be manufactured by the manufacturing method in this order.
FIG. 32 is a schematic cross-sectional view showing a fourth example of a semiconductor package.
The semiconductor package 40 shown in FIG. 32 has the same configuration except that the configuration of the composite material 30 is different from that of the semiconductor package 40 shown in FIG. In the composite material 30, the resin 59 is filled in the portion removed by the composite material removal step by the resin filling step. The composite material 30 and the semiconductor element 42 are electrically connected by solder balls 45 provided on the conductor 32 that is not removed.

<Mask layer forming step>
The above-described mask layer forming step is a step of forming a mask layer having a predetermined opening pattern (opening) on the surface of the composite material after the above [metal filling step].
The mask layer is formed by, for example, a method in which an image recording layer is formed on the surface of the composite material described above, and then energy is applied to the image recording layer by exposure or heating to develop it into a predetermined opening pattern. Can be formed. Here, the material for forming the above-mentioned image recording layer is not particularly limited, and a conventionally known material for forming a photosensitive layer (photoresist layer) or a heat-sensitive layer can be used. If necessary, an infrared absorber or the like These additives may also be contained.

<Mask layer removal process>
The above-described mask layer removing step is a step of removing the above-described mask layer.
Here, the method for removing the above-described mask layer is not particularly limited. For example, the above-described mask is prepared using a liquid that dissolves the above-described mask layer and does not dissolve the above-described aluminum substrate and the above-described anodic oxide film. A method of dissolving and removing the layer can be mentioned. As such a liquid, for example, when a photosensitive layer and a heat-sensitive layer are used for the above-described mask layer, a known developer may be used.

<Filling metal removal process>
The above-described filling metal removing step is a step of removing the metal M2 and the metal M1 constituting the conductor 32 in the composite material existing under the opening of the mask layer. Here, the method for removing the metal M2 and the metal M1 is not particularly limited, and examples thereof include a method of dissolving the metal M2 and the metal M1 using a hydrogen peroxide solution, an acidic aqueous solution, or a mixture thereof. It is done.

<Composite material removal process>
The above-described composite material removing step is a step of removing the composite material existing under the opening of the mask layer.
Here, the method for removing the above-described composite material is not particularly limited, and examples thereof include a method of dissolving the anodic oxide film of the composite material using an alkaline etching aqueous solution or an acidic aqueous solution.

<Washing treatment>
It is preferable to carry out water washing after the above-described processes. For washing, pure water, well water, tap water, or the like can be used. A nip device may be used to prevent the processing liquid from being brought into the next process.

[Semiconductor package manufacturing method 5]
The semiconductor package 40 shown in FIG. 33 can be manufactured by a manufacturing method including a wiring layer forming process in which at least one wiring layer is formed on the surface of the exposed composite material after the above [substrate removing process]. .
FIG. 33 is a schematic cross-sectional view showing a fifth example of a semiconductor package.
The semiconductor package 40 shown in FIG. 33 has the same configuration as the semiconductor package 40 shown in FIG. 29 except that the wiring substrate 50 is provided on the back surface 30b of the composite material 30.
In the wiring board 50, a wiring layer 54 is provided on an insulating base 52 having electrical insulation. One of the wiring layers 54 is electrically connected to the conductor 32 of the composite material 30, and the other is electrically connected to the solder balls 45. Thereby, a signal or the like can be taken out from the semiconductor package 40 from the semiconductor element 42. Further, a signal, voltage, current, or the like can be supplied to the semiconductor element 42 from the outside of the semiconductor package 40.

[Semiconductor Package Manufacturing Method 6]
FIG. 34 shows a manufacturing method including a step of bonding the semiconductor package and the package substrate on which the semiconductor element is mounted at least once after the wiring layer forming step of [Semiconductor package manufacturing method 5]. Thus, a PoP (Package on Package) substrate 41 in which semiconductor package substrates are stacked can be produced.

FIG. 34 is a schematic cross-sectional view showing a configuration in which semiconductor package substrates are stacked.
A PoP substrate 41 shown in FIG. 34 includes a semiconductor package substrate 40 a and a semiconductor package substrate 40 b that are stacked and electrically connected by solder balls 68. The semiconductor package substrate 40 a is provided with a wiring layer 56 on the surface 30 a of the composite material 30. The wiring layer 56 is provided with, for example, two wirings 58 on the insulating layer 57. Each wiring 58 is electrically connected to one semiconductor element 42 by a solder ball 45. The wiring layer 56 and one semiconductor element 42 are covered with a mold resin 44.
A wiring layer 60 is provided on the back surface 30 b of the composite material 30. The wiring layer 60 is provided with two wiring layers 62 on an insulating base 61. Each wiring layer 62 is electrically connected to the solder ball 45 via the conductor 32 of the composite material 30.
In the semiconductor package substrate 40b, for example, electrodes 65 are provided on both sides of the substrate 64, and two electrodes 66 are provided in the center. Each electrode 66 in the center is electrically connected to the semiconductor element 42 via the solder ball 45. The electrodes 65 on both sides of the substrate 64 are electrically connected to the wiring layer 62 of the semiconductor package substrate 40a via solder balls 68, respectively.

[Semiconductor package manufacturing method 7]
After the insulating layer forming step described in [Semiconductor Package Manufacturing Method 2], the manufacturing method includes a step of forming a hole in the insulating layer to expose the above-described wiring under the insulating layer. The semiconductor package 40 shown in FIG. 35 can be manufactured. In this way, a component built-in substrate can be manufactured.
FIG. 35 is a schematic cross-sectional view showing a sixth example of a semiconductor package.
The semiconductor package 40 shown in FIG. 35 has the same configuration as the semiconductor package 40 shown in FIG. 30 except that a hole 49 for exposing the wiring 47 is provided in the insulating layer 48.

  The present invention is not limited to the above-described embodiment, and examples of mounting forms include SoC (System on a chip), SiP (System in Package), PoP (Package on Package), and PiP (Polysilicon Insulater). Polysilicon), CSP (Chip Scale Package), TSV (Through Silicon Via), and the like.

  More specifically, for example, the composite material of the present invention can be used as a ground part and a heat conduction part in addition to a data signal of a semiconductor element and a connection of a power source.

Further, the composite material of the present invention can be used as a ground part and a heat conduction part in addition to connection of a data signal or a power source between two or more semiconductor elements. Examples of such an embodiment include those using the composite material of the present invention as an interposer in the following examples.
・ 3D SoC logic devices (for example, homogeneous substrates (multiple layers of FPGA (Field Programmable Gate Array) stacked on an interposer), heterogeneous substrates (digital devices, analog devices, and RF devices on an interposer) , MEMS and memory stacked)
3D SiP (Wide I / O) combining logic and memory (for example, a stack of CPU and DRAM above or below the interposer, and a stack of GPU and DRAM above or below the interposer , ASIC / FPGA and Wide I / O memory stacked above or below the interposer, APE and Wide I / O memory stacked above or below the interposer, etc.)
・ 2.5-dimensional heterogeneous substrate combining SoC and DRAM

  The composite material of the present invention can also be used for electrical connection between the semiconductor package 40 and the printed wiring board 70 as shown in FIG. The printed wiring board 70 is provided on the back surface 30 b of the composite material 30 of the semiconductor package 40. In the printed wiring board 70, for example, a wiring layer 74 is provided on an insulating base 72 made of resin. The wiring layer 74 is electrically connected to the conductor 32 on the back surface 30 b of the composite material 30.

The composite material of the present invention can also be used for connection (PoP) between two or more semiconductor packages. As an aspect in this case, for example, the composite material of the present invention is arranged on the upper and lower surface sides. A mode in which two semiconductor packages are connected to each other through a predetermined wiring can be cited.
The composite material of the present invention can also be used in a multichip package in which two or more semiconductor elements are stacked on a substrate or packaged in a flat manner. For example, the present invention includes, for example, the present invention. There is a mode in which two semiconductor elements are laminated on the composite material and connected via a predetermined wiring.

(Electronic device)
Hereinafter, an electronic device using the composite material for the anisotropic conductive member will be described.
FIG. 39 is a schematic view showing a first example of an electronic device according to an embodiment of the present invention. FIG. 40 is a schematic cross-sectional view showing an example of the configuration of the terminals of the semiconductor element of the electronic device according to the embodiment of the present invention. FIG. 41 is a schematic diagram illustrating a second example of the electronic device according to the embodiment of the invention. FIG. 42 is a schematic diagram illustrating a third example of the electronic device according to the embodiment of the invention. FIG. 43 is a schematic diagram illustrating a fourth example of the electronic device according to the embodiment of the invention. The joined body constitutes a part of the electronic device. A semiconductor element to be described later is, for example, a member having a conductive region of a bonded body and bonded to an anisotropic conductive member. The conductive region corresponds to a terminal or the like responsible for the conduction of the semiconductor element.

  Like the electronic device 80 shown in FIG. 39, the semiconductor element 84 and the semiconductor element 86 are joined in the stacking direction Ds via the anisotropic conductive member 82 having anisotropic conductivity, and the semiconductor element 84 and the semiconductor element 86 are joined. May be electrically connected. The anisotropic conductive member 82 includes a conductor 32 (see FIG. 10) that conducts in the stacking direction Ds, and functions as a TSV (Through Silicon Via). The anisotropic conductive member 82 can also be used as an interposer.

For example, as shown in FIG. 40, the semiconductor elements 84 and 86 each have a plurality of terminals 90. The plurality of terminals 90 are for bonding semiconductors. The terminal 90 includes a terminal 90a that electrically connects the semiconductor elements 84 and 86, and a terminal 90b that joins the semiconductor elements 84 and 86 but does not electrically connect them. The terminal 90a is for taking out signals from the semiconductor elements 84 and 86 to the outside. The terminal 90b is for radiating the heat generated in the semiconductor elements 84 and 86 to the outside and maintaining the bonding strength of the electronic device 80.
The terminal 90 has a configuration shown in FIG. 40, for example. As shown in FIG. 40, the semiconductor elements 84 and 86 include a semiconductor layer 92, a rewiring layer 94, and a passivation layer 96. The rewiring layer 94 and the passivation layer 96 are electrically insulated insulating layers. On the surface 92a of the semiconductor layer 92, an element region (not shown) in which a circuit or the like that exhibits a specific function is formed. The element region will be described later. The surface 92a of the semiconductor layer 92 corresponds to the surface on which the semiconductor terminals 90 are provided.
A rewiring layer 94 is provided on the surface 92 a of the semiconductor layer 92. In the rewiring layer 94, a wiring 97 that is electrically connected to the element region of the semiconductor layer 92 is provided. A pad 98 is provided on the wiring 97, and the wiring 97 and the pad 98 are electrically connected. With the wiring 97 and the pad 98, signals can be exchanged with the element region, and a voltage or the like can be supplied to the element region.

A passivation layer 96 is provided on the surface 94 a of the rewiring layer 94. In the passivation layer 96, a terminal 90 a is provided on a pad 98 provided on the wiring 97. The terminal 90a is electrically connected to the semiconductor layer 92.
Further, the rewiring layer 94 is not provided with the wiring 97, but only the pad 98 is provided. A terminal 90 b is provided on a pad 98 that is not provided on the wiring 97. The terminal 90b is not electrically connected to the semiconductor layer 92.

  The end surface 90c of the terminal 90a and the end surface 90c of the terminal 90b are both coincident with the surface 96a of the passivation layer 96 and are in a so-called flush state, and the terminals 90a and 90b protrude from the surface 96a of the passivation layer 96. Absent. The terminals 90a and 90b shown in FIG. 40 are flush with the surface 96a of the passivation layer 96, for example, by polishing.

The terminals 90a and 90b are not limited to being flush with the surface 96a of the passivation layer 96, and may protrude from the surface 96a of the passivation layer 96. In this case, the recess amount that is the protruding amount of the terminal 90a and the terminal 90b with respect to the surface 96a of the passivation layer 96 is, for example, not less than 200 nm and not more than 1 μm.
If the recess amount is less than 200 nm, it is substantially the same as the non-projecting configuration shown in FIG. On the other hand, when the recess amount exceeds 1 μm, it is the same as a general configuration in which a pad electrode is provided, and it is necessary to join using a solder ball or the like.
Since the terminals 90a and 90b protrude from the surface 96a of the passivation layer 96, a resin layer (not shown) for protecting the terminals 90a and 90b may be provided on the surface 96a of the passivation layer 96. .

The above-mentioned recess amount is obtained by obtaining an image of a cross section including the terminals 90a and 90b in the semiconductor elements 84 and 86, obtaining the outline of the terminal 90a and the outline of the terminal 90b by image analysis, and obtaining the end face 90c and the terminal 90c of the terminal 90a. The end face 90c of 90b is detected. It can be obtained by obtaining the distance from the surface 96a of the passivation layer 96 to the end face 90c of the terminal 90a and the distance from the end face 90c of the terminal 90b.
The end surface 90c of the terminal 90a and the end surface 90c of the terminal 90b are both surfaces that are farthest from the surface 96a of the passivation layer 96, and are generally referred to as upper surfaces.

The semiconductor layer 92 is not particularly limited as long as it is a semiconductor and is made of silicon or the like, but is not limited thereto, and may be silicon carbide, germanium, gallium arsenide, gallium nitride, or the like. Good.
The rewiring layer 94 is made of an electrically insulating material such as polyimide.
The passivation layer 96 is also made of an electrically insulating material, for example, silicon nitride (SiN) or polyimide.
The wiring 97 and the pad 98 are made of a conductive material, for example, copper, copper alloy, aluminum, aluminum alloy, or the like.

The terminal 90a and the terminal 90b are made of a conductive material like the wiring 97 and the pad 98, and are made of, for example, a metal or an alloy. Specifically, the terminals 90a and 90b are made of, for example, copper, copper alloy, aluminum, aluminum alloy, or the like.
Note that the terminals 90a and 90b are not limited to being made of metal or alloy as long as they have conductivity, and are used for what are called terminals or electrode pads in the semiconductor element field. Materials can be used as appropriate.

In addition to the configuration shown in FIG. 39, the electronic device 80 includes, for example, a semiconductor element 84, a semiconductor element 86, and a semiconductor element via an anisotropic conductive member 82 using a composite material like the electronic device 80 shown in FIG. 41. 88 may be stacked in the stacking direction Ds, joined, and electrically connected.
Further, as in the electronic device 80 shown in FIG. 42, the semiconductor element 84, the semiconductor element 86, and the semiconductor element 88 are stacked and bonded in the stacking direction Ds using the interposer 87 and the anisotropic conductive member 82, and An electrically connected configuration may be used.

Further, the electronic device 80 shown in FIG. 43 may function as an optical sensor. In the electronic device 80 shown in FIG. 43, the semiconductor element 110 and the sensor chip 112 are stacked in the stacking direction Ds via the anisotropic conductive member 82. The sensor chip 112 is provided with a lens 114.
The semiconductor element 110 is formed with a logic circuit, and the configuration thereof is not particularly limited as long as signals obtained by the sensor chip 112 can be processed.
The sensor chip 112 has an optical sensor that detects light. The optical sensor is not particularly limited as long as it can detect light. For example, a charge coupled device (CCD) image sensor or a complementary metal oxide semiconductor (CMOS) image sensor is used.
The configuration of the lens 114 is not particularly limited as long as it can collect light on the sensor chip 112. For example, a lens called a microlens is used.

Note that the semiconductor element 84, the semiconductor element 86, and the semiconductor element 88 described above have element regions (not shown).
The element region is a region where various element constituent circuits such as capacitors, resistors, and coils for functioning as electronic elements are formed. In the element region, for example, a memory circuit such as a flash memory, a region where a logic circuit such as a microprocessor and an FPGA (field-programmable gate array) is formed, a communication module such as a wireless tag, and wiring are formed. There are areas. In addition to this, a transmission circuit or MEMS (Micro Electro Mechanical Systems) may be formed in the element region. The MEMS is, for example, a sensor, an actuator, an antenna, or the like. Examples of the sensor include various sensors such as acceleration, sound, and light.

As described above, an element configuration circuit or the like is formed in the element region, and a rewiring layer (not shown) is provided in the semiconductor element, for example.
In a stacked device, for example, a combination of a semiconductor element having a logic circuit and a semiconductor element having a memory circuit can be used. Further, all the semiconductor elements may have a memory circuit, and all the semiconductor elements may have a logic circuit. Further, the combination of the semiconductor elements in the electronic device 80 may be a combination of a sensor, an actuator, an antenna, and the like, a memory circuit, and a logic circuit, and is appropriately determined according to the use of the electronic device 80 and the like.

[Semiconductor element]
The semiconductor element is used for the above-described semiconductor package and electronic device. The semiconductor element is not particularly limited, and other than those described above, for example, logic LSI (Large Scale Integration) (for example, ASIC (Application Specific Integrated Circuit), FPGA (Field Programmable Gate Array), ASSP (Application Specific Standard Product). )), Microprocessor (for example, CPU (Central Processing Unit), GPU (Graphics Processing Unit), etc.), memory (for example, DRAM (Dynamic Random Access Memory), HMC (Hybrid Memory Cube), MRAM (Magnetic RAM: magnetic memory) ) And PCM (Phase-Change Memory), ReRAM (Resistive RAM), FeRAM (Ferroelectric RAM), flash memory (NAND (Not AND) flash), etc.), LED (Light Emitting Diode), (for example, micro flash for portable terminals, in-vehicle use Projector light source, LCD backlight, general lighting, etc.), power device, analog IC (Integrated Circuit), (eg DC (Direct Current) -DC (Direct Current) converter, insulated gate bipolar transistor (IGBT), etc.), MEMS (Micro Electro Mechanical Systems) (for example, acceleration sensors, pressure sensors, vibrators, gyro sensors, etc.), wireless (for example, GPS (Global Positioning System), FM (Frequency Modulation), NFC (Nearfield communication), RFEM (RF Expansion) Module), MMIC (Monolithic Microwave Integrated Circuit), WLAN (Wireless Local Area Network), etc.), discrete element, BSI (Back Side Illumination), CIS (Contact Image Sensor), camera module, CMOS (Complementary Metal Oxide Semiconductor), Passive device, SAW (Surface A Examples include a coustic wave (RF) filter, an RF (Radio Frequency) filter, an RFIPD (Radio Frequency Integrated Passive Devices), and a BB (Broadband).
For example, a single semiconductor element is completed, and the semiconductor element alone exhibits a specific function such as a circuit or a sensor.

The electronic device is not limited to a one-to-multiple form in which a plurality of semiconductor elements are joined to one semiconductor element, but a plurality of forms in which a plurality of semiconductor elements and a plurality of semiconductor elements are joined. Multiple forms may be used.
44 is a schematic view showing a fifth example of the electronic device according to the embodiment of the present invention, FIG. 45 is a schematic view showing a sixth example of the electronic device according to the embodiment of the present invention, and FIG. FIG. 47 is a schematic diagram illustrating a seventh example of the electronic device according to the embodiment of the invention, and FIG. 47 is a schematic diagram illustrating an eighth example of the electronic device according to the embodiment of the present invention.

For example, as shown in FIG. 44, the semiconductor element 86 and the semiconductor element 88 are joined to one semiconductor element 84 by using an anisotropic conductive member 82, as shown in FIG. The electronic device 80a in the form connected to the is illustrated. The semiconductor element 84 may have an interposer function.
For example, a plurality of devices such as a logic chip having a logic circuit and a memory chip can be stacked on a device having an interposer function. In this case, bonding can be performed even if the electrode size is different for each device.
In the electronic device 80b shown in FIG. 45, the electrodes 118 are not the same in size but are mixed in different sizes. However, a semiconductor element 84 is used for the semiconductor element 84 by using the anisotropic conductive member 82. The element 86 and the semiconductor element 88 are joined and electrically connected. Further, the semiconductor element 116 is joined to the semiconductor element 86 using the anisotropic conductive member 82 and is electrically connected thereto. The semiconductor element 117 is joined and electrically connected across the semiconductor element 86 and the semiconductor element 88 using the anisotropic conductive member 82.

  In addition, as in the electronic device 80c shown in FIG. 46, the semiconductor element 86 and the semiconductor element 88 are joined and electrically connected to one semiconductor element 84 using the anisotropic conductive member 82. Yes. Further, the semiconductor element 116 and the semiconductor element 117 are bonded to the semiconductor element 86 using the anisotropic conductive member 82, the semiconductor element 121 is bonded to the semiconductor element 88 using the anisotropic conductive member 82, and electrically A connected configuration can also be adopted.

In the case of the configuration described above, a light emitting element such as a VCSEL (Vertical Cavity Surface Emitting Laser) and a light receiving element such as a CMOS (Complementary Metal Oxide Semiconductor) image sensor are stacked on the device surface including the optical waveguide. This makes it possible to support silicon photonics that assumes high frequencies.
For example, as in an electronic device 80d shown in FIG. 47, a semiconductor element 86 and a semiconductor element 88 are joined and electrically connected to one semiconductor element 84 using an anisotropic conductive member 82. Yes. Further, the semiconductor element 116 and the semiconductor element 117 are bonded to the semiconductor element 86 using the anisotropic conductive member 82, the semiconductor element 121 is bonded to the semiconductor element 88 using the anisotropic conductive member 82, and electrically It is connected. The semiconductor element 84 is provided with an optical waveguide 123. The semiconductor element 88 is provided with a light emitting element 125, and the semiconductor element 86 is provided with a light receiving element 126. The light Lo output from the light emitting element 125 of the semiconductor element 88 passes through the optical waveguide 123 of the semiconductor element 84 and is emitted as the outgoing light Ld to the light receiving element 126 of the semiconductor element 86. Thereby, it can respond to the above-mentioned silicon photonics.
In the anisotropic conductive member 82, a hole 122 is formed at a location corresponding to the optical path of the light Lo and the emitted light Ld.

  The present invention is basically configured as described above. The metal film, structure, composite material, metal film manufacturing method, structure manufacturing method, and composite material manufacturing method of the present invention have been described in detail above, but the present invention is not limited to the above-described embodiments. Of course, various improvements or modifications may be made without departing from the spirit of the present invention.

The features of the present invention will be described more specifically with reference to the following examples. The materials, reagents, substance amounts and ratios thereof, and operations shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the following examples.
In this example, defects were evaluated for Examples 1 to 9 and Comparative Examples 1 to 3 shown in Table 1 below. The evaluation results of the defects are shown in Table 1 below. In Table 1 below, “-” indicates that there is no applicable item. Next, defects that are evaluation items will be described.

(Number of defects)
The manufactured structure was filled with copper to obtain a composite material. After polishing one side of the composite material, an attempt was made to find defects by observing the polished surface with an optical microscope. Then, the number of defects was counted to determine the number of defects per area of 5 mm × 5 mm, and the number of defects was evaluated according to the following defect number evaluation criteria.
The above-described single-side polishing was performed as follows. First, the composite material manufactured on an 8-inch wafer was attached with Q-chuck (registered trademark) (manufactured by Maruishi Sangyo Co., Ltd.), and the composite material was subjected to arithmetic average roughness (JIS (Japanese Industrial Standard) using a polishing apparatus manufactured by MAT. ) Polishing was performed until B0601: 2001) was 0.02 μm. Abrasive grains containing alumina were used for polishing.
Evaluation criteria for the number of defects “A”: less than 100 pieces / (5 mm × 5 mm) “B”: more than 100 pieces / (5 mm × 5 mm) and less than 500 pieces / (5 mm × 5 mm) “C”: 500 pieces / (5 mm × 5 mm) or more and less than 1000 pieces / (5 mm × 5 mm) “D”: 1000 pieces / (5 mm × 5 mm) or more

Hereinafter, Examples 1 to 9 and Comparative Examples 1 to 3 will be described.
Example 1
<Production of metal film>
Using a continuous casting method, a molten aluminum having a purity of 99.992% by mass was solidified and rolled at a cooling rate of 600 ° C./second to obtain a 100 μm aluminum foil. This aluminum foil is bonded onto a wafer having a diameter of 200 mm (8 inches) using Q-chuck (registered trademark) (manufactured by Maruishi Sangyo Co., Ltd.), and then subjected to a smoothing process using electropolishing as shown below. A membrane was obtained.
The thickness of the metal film was 100 μm. The thickness of the metal film is a value obtained by directly measuring the above aluminum foil with a micrometer.
The purity of the aluminum foil was measured using an ICP (Inductively Coupled Plasma) emission analysis method after melting and hardening a molten aluminum used for continuous casting.

The number of the second phase particles was obtained by isolating the second phase particles of the metal film using a hot phenol method as described below. The number of second phase particles was counted to determine the number per 1 mm ³ .
A 0.1 g sample piece of a metal film was added to phenol (170 to 180 ° C., 150 ml) boiled in a state where steam was not leaked to the outside using a Liebig condenser or the like, and heated and dissolved for 1 to 5 minutes. After confirming dissolution, heating was stopped, air cooling was performed for 10 minutes, and when the temperature dropped to 140 ° C, 50 ml (milliliter) of benzyl alcohol was added and the phenol solution was diluted and cooled to 50 ° C or lower. After 800 ml of alcohol was added to dilute the solution 5 times, the solution was separated every 200 ml and filtered through a membrane filter having a mesh size of 0.1 micron. Each filter was washed twice with benzyl alcohol with methanol and dried to obtain an intermetallic compound as a dissolution residue. The number of intermetallic compound particles captured on each filter was counted from above by directly observing the filter surface with an electron microscope. The observation magnification is 10,000 times, the number of observation fields is 50 fields / one filter, the number of intermetallic compounds captured on one filter is calculated, and the total of five filters is the metal in 0.1 g of the base material. It calculated as the number of intermetallic compounds. It was identified by performing X-ray diffraction that the dissolution residue was an intermetallic compound.
In Example 1, the number of second phase particles (pieces / mm ³ ) was more than 10 ^{2 and} 10 ⁴ or less.
The surface roughness Rt of the metal film was measured using a tapping mode of AFM (Atomic Force Microscope, manufactured by SII (Seiko Instruments)). In Example 1, the surface roughness Rt was more than 0.05 μm and 0.1 μm or less.

<Smoothing process>
Electropolishing was performed as a smoothing treatment. Electropolishing was carried out on the above metal film using an electropolishing liquid having the following composition under conditions of a voltage of 25 V, a liquid temperature of 65 ° C., and a liquid flow rate of 3.0 m / min.
The cathode was a carbon electrode, and GP0110-30R (manufactured by Takasago Seisakusho Co., Ltd.) was used as the power source. Further, the flow rate of the electrolyte was measured using a vortex flow monitor FLM22-10PCW (manufactured by ASONE Corporation).
(Electrolytic polishing liquid composition)
-660 mL of 85% by mass phosphoric acid (reagent manufactured by Wako Pure Chemical Industries, Ltd.)
・ Pure water 160mL
・ Sulfuric acid 150mL
・ Ethylene glycol 30mL

The following treatment was performed on the metal film.
<Anodizing process>
Subsequently, the metal film after the electrolytic polishing treatment was subjected to anodizing treatment by a self-ordering method according to the procedure described in JP-A-2007-204802. The anodizing treatment was performed as a pre-anodizing treatment described later and a re-anodizing treatment described later, and the anodizing treatment was performed twice in total. A structure was formed by anodizing and removing the barrier layer described below.
The metal film after the electropolishing treatment was subjected to a preanodization treatment for 5 hours with an electrolyte solution of 0.50 mol / L oxalic acid at a voltage of 40 V, a liquid temperature of 16 ° C., and a liquid flow rate of 3.0 m / min. .
Thereafter, a film removal treatment was performed in which the metal film after the pre-anodizing treatment was immersed in a mixed aqueous solution (liquid temperature: 50 ° C.) of 0.2 mol / L chromic anhydride and 0.6 mol / L phosphoric acid for 12 hours.
Thereafter, reanodization treatment was performed for 3 hours and 45 minutes with an electrolyte solution of 0.50 mol / L oxalic acid under conditions of a voltage of 40 V, a liquid temperature of 16 ° C., and a liquid flow rate of 3.0 m / min, and a film thickness of 30 μm. An anodic oxide film was obtained.
In both the pre-anodizing treatment and the re-anodizing treatment, the cathode was a stainless electrode, and the power supply was GP0110-30R (manufactured by Takasago Seisakusho Co., Ltd.). Further, NeoCool BD36 (manufactured by Yamato Scientific Co., Ltd.) was used as the cooling device, and Pair Stirrer PS-100 (manufactured by EYELA Tokyo Rika Kikai Co., Ltd.) was used as the stirring and heating device. Furthermore, the flow rate of the electrolytic solution was measured using a vortex flow monitor FLM22-10PCW (manufactured by ASONE Corporation).

<Barrier layer removal process>
Next, electrolytic treatment (electrolytic removal treatment) was performed while the voltage was continuously decreased from 40 V to 0 V at a voltage drop rate of 0.2 V / sec under the same treatment liquid and treatment conditions as those of the above-described anodizing treatment.
After that, an etching process (etching removal process) is performed by immersing in 5% by mass phosphoric acid at 30 ° C. for 30 minutes to remove the barrier layer at the bottom of the micropore of the anodized film, and to expose aluminum through the micropore. It was.

Here, the average opening diameter of the micropores existing as through-holes in the structure was 60 nm. In addition, the average opening diameter was calculated as an average value obtained by taking a surface photograph (magnification 50000 times) with an FE-SEM (Field emission-Scanning Electron Microscope) and measuring 50 points.
The density of micropores present in the anodic oxide film was about 100 million / mm ² . The micropore density was measured and calculated by the method described in paragraphs [0168] and [0169] of JP-A-2008-270158.
The straight tube ratio of the structure is determined by immersing the metal film in a 20% by mass mercury chloride aqueous solution (sublimation) at 20 ° C. for 3 hours to dissolve and remove the metal film, and then microscopic per unit area on each side of the structure. The number of pores was determined, and the straight pipe ratio was calculated from the ratio of the number of micropores per unit area on both sides. In Example 1, the straight pipe ratio was 99%.

<Filling process>
Next, electrolytic plating was performed using the metal film as the cathode and platinum as the positive electrode.
Specifically, a copper plating solution having the composition shown below was used and constant current electrolysis was performed to produce a composite material in which copper was filled in the micropores.
Here, the constant current electrolysis is performed by cyclic voltammetry in a plating solution using a power source (HZ-3000) manufactured by Hokuto Denko Co., Ltd. using a plating apparatus manufactured by Yamamoto Metal Testing Co., Ltd. After confirming the potential, the treatment was performed under the following conditions.
(Copper plating composition and conditions)
・ Copper sulfate 100g / L
・ Sulfuric acid 50g / L
・ Hydrochloric acid 15g / L
・ Temperature 25 ℃
・ Current density 10A / dm ²

(Example 2)
Example 2 is different from Example 1 in that the metal film has a multilayer structure, the thickness of the metal film, the purity of aluminum, the number of second phase particles, the surface roughness Rt, the method for producing the aluminum layer, and The smoothing method was different, and the rest was the same as in Example 1. The aluminum layer corresponds to the metal film of Example 1.
In Example 2, the thickness of the metal film was 20 μm, and the purity of aluminum was 99.998% by mass. Further, the number of second phase particles was less than 100 / mm ³ . The surface roughness Rt was 0.05 μm or less.
The metal film has a three-layer structure of an aluminum layer, a titanium layer, and an aluminum layer, and the outermost layer is composed of an aluminum layer. The ratio of the titanium layer to the thickness of the metal film was 1%.
The aluminum layer was formed by the ion plating method shown below.
In the ion plating method, an aluminum material having a purity of 99.990% is used as an evaporation material while the inside of the chamber is maintained at 10 ⁻³ Pa, and high-frequency plasma (RF 13.5 MHz, output 300 W) is used as an acceleration source. The film was formed for a time to obtain an aluminum layer having a thickness of 10 μm. The thickness of the aluminum layer was measured with a film thickness meter.
The ion plating method had a cooling rate of 50 ° C./second. For the smoothing treatment, a gas cluster ion beam (GCIB) using argon was used. The titanium layer was formed on the aluminum layer by sputtering. The thickness of the titanium layer was measured with a film thickness meter.

(Example 3)
Example 3 was the same as Example 2 except that the magnesium layer was replaced with a titanium layer, and the ratio of the magnesium layer to the metal film thickness was 2%, as compared to Example 2. . Note that the magnesium layer was formed on the aluminum layer by sputtering. The thickness of the magnesium layer was measured with a film thickness meter.

(Example 4)
Example 4 is different from Example 1 in that the metal film has a multilayer structure, the thickness of the metal film, the purity of aluminum, the number of second phase particles, the straight pipe ratio, the method for producing the aluminum layer, and smoothing The method and the number of times of anodizing treatment were different, and the others were the same as in Example 1.
In Example 4, the thickness of the metal film was 10 μm, and the purity of aluminum was 99.998% by mass. Further, the number of second phase particles was less than 100 / mm ³ .
The metal film has a two-layer structure of an aluminum layer and a copper layer, and the outermost layer is composed of an aluminum layer. The copper layer was formed on the aluminum layer by sputtering, and the ratio of the copper layer to the metal film thickness was 3%. The thickness of the copper layer was measured with a film thickness meter.
The aluminum layer was formed by an ion plating method. The method for forming the aluminum layer was the same as in Example 2. For the smoothing treatment, a gas cluster ion beam (GCIB) using argon was used. The smoothing process was the same as in Example 2. The straight pipe ratio was 98%.
Moreover, the anodizing process was implemented only once.

(Example 5)
Example 5 is different from Example 1 in that the metal film has a multilayer structure, the thickness of the metal film, the purity of the aluminum, and the method for producing the aluminum layer, and the others are the same as Example 1. .
In Example 5, the thickness of the metal film was 15 μm, and the purity of aluminum was 99.99% by mass.
The metal film has a two-layer structure of an aluminum layer and a copper layer, and the outermost layer is composed of an aluminum layer. The ratio of the copper layer to the thickness of the metal film was 3%.
The aluminum layer was formed by the following vapor deposition method. In the vapor deposition method, an aluminum layer having a purity of 99.990% was used as an evaporation material in a state where the inside of the chamber was maintained at 10 ⁻³ Pa, and an aluminum layer having a thickness of 15 μm was obtained. The thickness of the aluminum layer was measured with a film thickness meter. The vapor deposition method had a cooling rate of 20 ° C./second. The copper layer was formed using a sputtering method. The thickness of the copper layer was measured with a film thickness meter.

(Example 6)
Example 6 is different from Example 1 in that the metal film has a multilayer structure, the thickness of the metal film, the purity of aluminum, the number of second phase particles, the straight pipe ratio, and the method for producing the aluminum layer, Otherwise, it was the same as Example 1.
In Example 6, the thickness of the metal film was 8 μm, and the purity of aluminum was 99.99% by mass. Further, the number of second phase particles was less than 100 / mm ³ .
The metal film has a two-layer structure of an aluminum layer and a copper layer, and the outermost layer is composed of an aluminum layer. The ratio of the copper layer to the thickness of the metal film was 3%.
The aluminum layer was formed by the sputtering method shown below. An RF magnetron sputtering apparatus was used for forming the aluminum layer.
In the sputtering method, a silicon wafer was used as the substrate, an aluminum lump (diameter 75 mm × thickness 3 mm) having a purity of 99.999%, and Ar (purity 99.999%) as a sputtering gas.
As a process for forming the aluminum layer, the distance between the sample and the target is 65 mm, and after evacuation to 3 × 10 Pa after the introduction of the sample, the substrate is heated to 200 ° C. when the argon gas pressure becomes 0.2 Pa. Sputtering was performed for 30 minutes at an output of cm ² to obtain an aluminum layer having a thickness of 8 μm. The thickness of the aluminum layer was measured with a film thickness meter. The sputtering method had a cooling rate of 90 ° C./second. The straight pipe ratio was 98%. The copper layer was formed using a sputtering method. The thickness of the copper layer was measured with a film thickness meter.

(Example 7)
Example 7 is different from Example 1 in that the metal film has a multilayer structure, the thickness of the metal film, the purity of aluminum, the number of second phase particles, the surface roughness Rt, and the method for producing the aluminum layer. Otherwise, the rest was the same as in Example 1.
In Example 7, the thickness of the metal film was 10 μm, and the purity of aluminum was 99.998% by mass. Further, the number of second phase particles was less than 100 / mm ³ . The surface roughness Rt was 0.05 μm or less.
The metal film has a two-layer structure of an aluminum layer and a copper layer, and the outermost layer is composed of an aluminum layer. The ratio of the copper layer to the thickness of the metal film was 3%.
The aluminum layer was formed by an ion plating method. The method for forming the aluminum layer was the same as in Example 2. For the smoothing treatment, a gas cluster ion beam (GCIB) using argon was used. The smoothing process was the same as in Example 2. The copper layer was formed using a sputtering method. The thickness of the aluminum layer and the copper layer was measured with a film thickness meter.
(Example 8)
Example 8 was the same as Example 2 except that the number of times of anodizing treatment was different from that of Example 2. In Example 8, the anodizing treatment was performed four times. In Example 8, compared with Example 2, the number of times of anodizing treatment was larger, so that the anodizing time was adjusted.
Example 9
Example 9 was the same as Example 7 except that the number of anodizing treatments was different from that in Example 7. In Example 9, the anodizing treatment was performed four times. In Example 9, the number of times of anodizing treatment was larger than that in Example 7, and thus the anodizing time was adjusted.

(Comparative Example 1)
In Comparative Example 1, the metal film has a multilayer structure as compared with Example 1, the thickness of the metal film, the purity of aluminum, the number of second phase particles, the surface roughness Rt, the straight pipe ratio, the aluminum layer The manufacturing method, the smoothing method, and the number of times of anodizing treatment were different, and the others were the same as in Example 1.
In Comparative Example 1, the thickness of the metal film was 4 μm, and the purity of aluminum was 99.990 mass%. Further, the number of second phase particles was less than 100 / mm ³ . The surface roughness Rt was 0.05 μm or less.
The metal film has a two-layer structure of an aluminum layer and a copper layer, and the outermost layer is composed of an aluminum layer. The ratio of the copper layer to the thickness of the metal film was 12%.
The aluminum layer was formed by an ion plating method. The method for forming the aluminum layer was the same as in Example 2, and the film thickness was measured in the same manner. The copper layer was formed using a sputtering method. The thickness of the copper layer was measured with a film thickness meter. For the smoothing treatment, a gas cluster ion beam (GCIB) using argon was used. The smoothing process was the same as in Example 2. Further, the straight pipe ratio was 82%. The anodizing treatment was performed once.

(Comparative Example 2)
Comparative Example 2 differs from Example 1 in the thickness of the metal film, the purity of aluminum, the number of second phase particles, the surface roughness Rt, the straight pipe ratio, and the production method of the aluminum layer. The other points are the same as in Example 1 except that the method is not implemented.
In Comparative Example 2, the thickness of the metal film was 120 μm, and the purity of aluminum was 99.998% by mass. The number of second phase particles was more than 10 ⁴ / mm ³ and the surface roughness Rt was more than 0.1 μm. Further, the straight pipe ratio was 70%.
The aluminum layer was formed by the following DC (Direct Chill) casting method. Smoothing treatment was not performed.
In the method of forming the aluminum layer, in the DC casting, the bottom block lowering speed was adjusted so that the cooling rate was 0.8 ° C./second according to a conventional method, and an ingot having a thickness of 300 mm was produced. After the surface layer of 20 mm of the ingot was removed by cutting (facing), a soaking treatment was performed at a temperature of 500 ° C. for 24 hours. Thereafter, hot rolling was performed, and cold rolling was performed to obtain a rolled plate having a thickness of 0.12 mm. The hot rolling start temperature was 350 ° C., and a heat treatment (intermediate annealing) was performed at 450 ° C. for 2 minutes using a continuous annealing furnace during the cold rolling.
One surface of the obtained rolled plate was chemically etched and further physically polished to thin the aluminum layer to 120 μm. The thickness of the aluminum layer is a value measured directly with a micrometer.

(Comparative Example 3)
In Comparative Example 3, the metal film has a multilayer structure as compared with Example 1, the thickness of the metal film, the purity of aluminum, the configuration of the metal layer, the number of second phase particles, the surface roughness Rt, the straight pipe The rate and the manufacturing method of the aluminum layer were different, and the others were the same as in Example 1.
The metal film had a thickness of 15 μm and the purity of aluminum was 99.5% by mass. The ratio of the copper layer to the thickness of the metal film was 3%, and the straight tube ratio was 89%.
The aluminum layer was formed by vapor deposition. The method for forming the aluminum layer was the same as in Example 5, and the film thickness was measured in the same manner. The copper layer was formed using a sputtering method. The thickness of the copper layer was measured with a film thickness meter. The anodization treatment was performed twice.

As shown in Table 1, Examples 1 to 9 were able to increase the straight pipe ratio as compared with Comparative Examples 1 to 3. Thereby, the composite material with few defects and few filling defects was able to be obtained.
In Comparative Example 1, the metal film was thin, the micropores were hardly formed regularly, and the straight pipe ratio was low. In Comparative Example 1, the metal film is thin and no defect is evaluated.
In Comparative Example 2, since the number of second phase particles was large and the surface roughness Rt was poor, the straight tube ratio was low. Furthermore, the comparative example 2 had many defects.
In Comparative Example 3, the purity of aluminum was poor and the straight tube ratio was low. Furthermore, Comparative Example 3 had many defects.

DESCRIPTION OF SYMBOLS 10 Metal film 10a, 12a, 17a, 19a, 20a, 30a Surface 10b, 20b, 30b Back surface 11 Metal film 12 1st metal layer 14 2nd metal layer 16 Heterogeneous metal layer 17, 19 Support body 18 Peeling layer 19b Adhesion Layer 20 Structure 21 Through-hole 22 Barrier layer 24 Anodized film 25, 25b Metal 25a Metal layer 28 Resin layer 29 Core 30 Composite material 32 Conductor 32a, 32b Protruding portion 34 Resin layer 40 Semiconductor package 40a, 40b Semiconductor package substrate 41 PoP substrate 42, 84, 86, 88 Semiconductor element 44 Mold resin 45 Solder ball 46 Support body 46, 49 Hole 47 Wiring 48 Insulating layer 50 Wiring substrate 52 Insulating substrate 54, 56 Wiring layer 57 Insulating layer 58 Wiring 60 Wiring Layer 61 Insulating substrate 62 Wiring layer 64 Substrate 65 Electrode 6 Electrode 68 Solder ball 70 Printed wiring board 72 Insulating substrate 74 Wiring layer 80, 80a, 80b, 80c, 80d Electronic device 82 Anisotropic conductive member 87 Interposer 90, 90a, 90b Terminal 90c End face 92 Semiconductor layer 92a Surface 94 Rewiring layer 94a Surface 96 Passivation layer 96a Surface 97 Wiring 98 Pad 100 Linear conductor 101 Insulating substrate 102 Signal wiring 103 Ground wiring 104 Insulating layer 105 Wiring layers 110, 116, 117, 121 Semiconductor element 112 Sensor chip 114 Lens 118 Electrode 122 Hole 123 Optical waveguide 125 Light emitting element 126 Light receiving element Ds Stacking direction Dt Thickness direction Ld Emission light Lo Light h Thickness ht Thickness p Center distance t Thickness w Width between conductors x direction

Claims (13)

A metal film used to form an anodized film,
Made of aluminum with a purity of 99.9% by mass or more,
The number of second phase particles isolated by the hot phenol method is less than 10 ⁴ / mm ³ ;
A metal film having a thickness of 5 μm or more.   The metal film according to claim 1, wherein the surface roughness Rt is 0.1 μm or less. It is a metal film having a multilayer laminated structure used for forming an anodic oxide film,
A first metal layer made of aluminum having a purity of 99.9% by mass or more, wherein the number of second phase particles isolated by a hot phenol method is less than 10 ⁴ / mm ³ , and the thickness is 5 μm or more;
A second metal layer having a composition different from that of the first metal layer;
The second metal layer has a thickness ratio of less than 10% with respect to the thickness of the metal film,
A metal film in which the first metal layer is disposed on the outermost layer.   The metal film according to claim 3, wherein the first metal layer has a surface roughness Rt of 0.1 μm or less.   The metal film according to claim 3, wherein the second metal layer is a valve metal. It is formed with the anodized film which has a through-hole comprised using the metal film of any one of Claims 1-5,
A structure in which the straight tube ratio of the through hole is 98% or more.   The composite material which has the structure of Claim 6, and the conductor with which the said through-hole of the said structure was filled. A method for producing a metal film used for forming an anodized film,
A method for producing a metal film, comprising forming a film using aluminum having a purity of 99.9% by mass or more and forming a film at a cooling rate of 20 ° C./second or more.   The method for producing a metal film according to claim 8, further comprising a flattening step of flattening a surface after the film forming step.   The manufacturing method of a structure which has the process of implementing at least anodic oxidation to the metal film of any one of Claims 1-5, and forming the anodic oxide film which has a through-hole.   The method of manufacturing a structure according to claim 10, wherein the anodization is performed at least once. Carrying out at least anodization on the metal film according to any one of claims 1 to 5 to form an anodized film having a through hole;
And a step of filling a through hole formed by the anodization with a conductive substance.   The method for producing a composite material according to claim 12, wherein the anodization is performed at least once.