JP5886417B2 - Surface treated copper foil - Google Patents

Description

The present invention relates to a surface-treated copper foil for a copper clad laminate for producing a flexible printed wiring board (FPC) capable of efficiently transmitting a high-frequency electric signal.

A flexible printed circuit board is manufactured by etching a copper foil of a substrate to form various wiring patterns, and connecting and mounting electronic components with solder. Copper foils are classified into electrolytic copper foils and rolled copper foils because of their production methods, and rolled copper foils having excellent bending resistance have been used favorably as copper foils for flexible substrates. In addition, in electronic devices such as personal computers and mobile communications, with the increase in communication speed and capacity, the frequency of electrical signals is increasing, and printed wiring boards and copper foils that can cope with this are demanded. .

In electronic devices such as personal computers and mobile communications, the frequency of electrical signals is high, but when the frequency of electrical signals exceeds 1 GHz, the effect of the skin effect, in which current flows only on the surface of the conductor, becomes significant. The effect of changing the current transmission path and increasing the conductor loss cannot be ignored. Also from this point, it is desired that the surface roughness of the copper foil is small.

The surface of the electrolytic copper foil of the raw foil is formed by electrodeposition of copper, and the surface of the rolled copper foil of the raw foil is formed by contact with a rolling roll. Therefore, generally the surface roughness of the rolled copper foil of raw foil is smaller than the surface roughness of the electrolytic copper foil. The electrodeposited particles in the roughening treatment are finer in the rolled copper foil. From this meaning, it can be said that the rolled copper foil is excellent as a copper foil for a high-frequency circuit.

On the other hand, the amount of data transport increases as the frequency increases, but the loss (attenuation) of signal power also increases and data cannot be read, so the circuit length of the FPC is limited. In order to reduce such loss (attenuation) of signal power, the conductor side tends to shift to a copper foil with a small surface roughness, and the resin side tends to shift from polyimide to liquid crystal polymer. The most desirable from the viewpoint of the skin effect is considered to be a copper foil with small roughness that does not form a roughening treatment.

The loss (attenuation) of signal power in an electronic circuit can be roughly divided into two. One of them is a conductor loss, that is, a loss caused by a copper foil, and the second is a dielectric loss, that is, a loss caused by a substrate. In the conductor loss, there is a skin effect in a high frequency region, and current has a characteristic that the current flows on the surface of the conductor. For this reason, if the copper foil surface is rough, a current flows along a complicated path. As described above, since the rolled copper foil has a smaller roughness than the electrolytic copper foil, the conductor loss tends to be small.

On the other hand, a liquid crystal polymer (LCP) is a polymer that exhibits optical anisotropy in a liquid phase (molten or solution), and needs to be laminated without an adhesive with a copper foil. The wholly aromatic polyester-based liquid crystal polymer is a halogen-free material that exhibits molecular orientation even in the molten state and maintains this state even in the solid state and exhibits thermoplasticity.

The characteristic of liquid crystal polymer (LCP) is that it has a low dielectric constant and a low dielectric loss tangent. Incidentally, while the relative dielectric constant of LCP is 3.3, the relative dielectric constant of polyimide is 3.5, and the dielectric loss tangent is 0.002 for LCP, whereas that of polyimide is 0.01. Therefore, the liquid crystal polymer (LCP) is superior in characteristics. In addition, the liquid crystal polymer (LCP) has a feature of low water absorption and low moisture absorption, and has a great advantage that there is little change in electrical characteristics and little change in dimensions.

In the rolled copper foil, for the purpose of maintaining handling properties, a rolled material that is rolled after the final annealing is optimal (for example, see Patent Document 1).
However, the strength of liquid crystal polymer (LCP) is lower than that of polyimide, and a material obtained by laminating copper foil has a serious problem that peel strength is difficult to be obtained. Increasing the roughness of the copper foil tends to increase the peel strength because a physical anchor effect is obtained, but the electrical characteristics at high frequencies are deteriorated due to the effect of the skin effect described above.
There are some proposals for copper foil for high-frequency circuits (see, for example, Patent Documents 2, 3, 4, and 5), which are effective from the viewpoint of simplifying the manufacturing process of rolled copper foil and reducing high-frequency transmission loss. The current situation is that there is no special technology.

Japanese Patent Laid-Open No. 2003-19311 Japanese Patent Publication No. 61-54592 Japanese Patent Publication No. 3-34679 Japanese Patent Publication No. 7-10564 JP-A-5-55746

The present invention has been made in view of the above-described problems, and its object is to provide copper for a flexible printed circuit board (FPC) in which a copper foil is laminated on a liquid crystal polymer (LCP) suitable for high frequency applications. When providing foil, it makes it a subject to obtain the copper foil which improved the peel strength.

The present inventors have found that transmission loss can be reduced for the following reason.
One of them is that it is greatly influenced by the surface of the copper foil in the high frequency region. As the surface roughness increases, transmission loss increases. Therefore, it is effective to adjust the surface roughness of the copper foil as small as possible.
The second is the use of a liquid crystal polymer (LCP) laminated substrate. However, for this purpose, it is necessary to increase the adhesive strength (peel strength) with the copper foil.
The present inventors have obtained the knowledge that a flexible printed circuit board (FPC) in which signal power loss (attenuation) is suppressed can be provided by solving the above problems.

Based on the above findings, the present invention provides the following inventions.
1) A surface-treated copper foil characterized by having an Si concentration of 2.0% or more and an N concentration of 2.0% or more in XPS survey measurement on the surface of the copper foil.

2) The surface-treated copper foil as described in 1) above, which is a copper foil for a flexible printed circuit board.

3) Copper-foil is rolled copper foil or electrolytic copper foil, The surface-treated copper foil as described in any one of said 1) -2) characterized by the above-mentioned.

4) The surface-treated copper foil according to any one of 1) to 3) above, which is a copper foil bonded to a flexible printed circuit board made of a liquid crystal polymer.

5) The 90 degree normal peel strength when bonded to a flexible printed circuit board made of a liquid crystal polymer is 0.3 kg / cm or more, according to any one of 1) to 4) above Surface treated copper foil.

6) The surface-treated copper foil according to any one of 1) to 5) above, which is bonded to a flexible printed circuit board that can be used under a high frequency exceeding 1 GHz.

According to the present invention, a surface-treated copper foil that can be used for high-frequency circuit applications can be produced, and the adhesive strength (peel strength) can be increased by applying the copper foil to a liquid crystal polymer (LCP) laminated substrate. And the outstanding effect that the flexible printed circuit board which can be used under the high frequency exceeding 1 GHz is realizable is acquired.

The surface-treated copper foil that can be used for high-frequency circuit applications is characterized in that the Si concentration is 2.0% or more and the N concentration is 2.0% or more in the XPS survey measurement of the copper foil surface. This makes it possible to increase the adhesive strength (peel strength) when the copper foil is bonded to the liquid crystal polymer (LCP) laminated substrate. As one means for achieving the Si concentration and the N concentration on the copper foil surface, silane treatment of the copper foil surface can be mentioned. Moreover, it is effective to use the surface-treated copper foil of the present application for a copper foil for a high-frequency circuit.

In the XPS survey measurement on the copper foil surface, if the Si concentration is less than 2.0% and the N concentration is less than 2.0%, the adhesive strength is not sufficient. In the XPS survey measurement on the copper foil surface, the Si concentration is If it exceeds 20.0% and the N concentration exceeds 40.0%, foaming occurs during lamination with LCP.

The silane coating method may be any of spraying of a silane coupling agent solution, coating with a coater, dipping, pouring and the like. Since these are already known techniques (see, for example, Japanese Patent Publication No. 60-15654), details are omitted.

About the Si and N density | concentration of copper foil surface, the survey spectrum was measured for the bonding surface with the resin of the surface-treated copper foil by XPS, and Si density | concentration and N density | concentration of the outermost surface were calculated | required. The analysis conditions are shown below.
Device: ULVAC-PHI Co., Ltd. 5600MC
Ultimate vacuum: 2.0 × 10 ⁻⁹ Torr
Excitation source: Monochromatic AlKα
Output: 210 W
Detection area: 800 μmφ
Incident angle: 45 degrees Degree angle: 45 degrees Without neutralizing gun

The copper foil with increased adhesive strength is a copper foil for a high-frequency circuit that is optimal for a flexible printed circuit board made of a liquid crystal polymer. That is, the 90 degree normal peel strength when bonded to a flexible printed circuit board made of a liquid crystal polymer can be 0.3 kg / cm or more.

Moreover, since the adhesive strength of the copper foil can be increased, it can be applied to a rolled copper foil and an electrolytic copper foil having a small surface roughness (less conductor loss), and an optimum copper foil for high-frequency circuits can be obtained. it can. The copper foil for high-frequency circuits makes it possible to produce a flexible printed circuit board that can be used under a high frequency exceeding 1 GHz.

The surface-treated copper foil according to the present invention comprises a roughening treatment layer and / or a heat treatment treatment layer and / or a rust prevention treatment layer and / or a chromate treatment layer and / or a plating treatment layer and / or a silane coupling treatment layer. You may have. The roughening treatment layer is not particularly limited, and any roughening treatment layer or a known roughening treatment layer can be applied. The heat-resistant treatment layer is not particularly limited, and any heat-resistant treatment layer or a known heat-resistant treatment layer can be applied. The rust prevention treatment layer is not particularly limited, and any rust prevention treatment layer or a known rust prevention treatment layer can be applied. The plating layer is not particularly limited, and any plating layer or a known plating layer can be applied. The chromate treatment layer is not particularly limited, and any chromate treatment layer or a known chromate treatment layer can be applied.

For example, the surface-treated copper foil according to the invention of the present application may be provided with a roughened layer on the surface by performing a roughening treatment for improving the adhesion to the insulating substrate, for example. The roughening treatment can be performed, for example, by forming roughened particles with copper or a copper alloy. The roughening process may be fine. The roughening treatment layer is a single layer selected from the group consisting of copper, nickel, phosphorus, tungsten, arsenic, molybdenum, chromium, cobalt and zinc, or a layer made of an alloy containing one or more of them. Also good.

Moreover, after forming the roughened particles with copper or a copper alloy, a roughening treatment can be performed in which secondary particles or tertiary particles are further formed of nickel, cobalt, copper, zinc alone or an alloy. Thereafter, a heat-resistant treatment layer or a rust-proof treatment layer may be formed of nickel, cobalt, copper, zinc alone or an alloy, and the surface thereof may be further subjected to a treatment such as a chromate treatment or a silane coupling treatment. . Alternatively, without heat treatment, a heat-resistant or anti-rust layer is formed of nickel, cobalt, copper, zinc alone or an alloy, and the surface is further treated with chromate or silane coupling. May be.

That is, one or more layers selected from the group consisting of a heat-resistant treatment layer, a rust-proof treatment layer, a chromate treatment layer, and a silane coupling treatment layer may be formed on the surface of the roughening treatment layer. One or more layers selected from the group consisting of a heat-resistant treatment layer, a rust prevention treatment layer, a chromate treatment layer, and a silane coupling treatment layer may be formed on the surface of the foil. In addition, the above-mentioned heat-resistant layer, rust prevention treatment layer, chromate treatment treatment layer, and silane coupling treatment layer may each be formed of a plurality of layers (for example, two or more layers, three or more layers, etc.). In the present invention, the “rust prevention treatment layer” includes a “chromate treatment layer”.

In consideration of adhesion to the resin, it is preferable to provide a silane coupling treatment layer as the outermost layer of the surface-treated copper foil.
In addition, as a roughening process layer, it is preferable that the primary particle layer of copper and the secondary particle layer which consists of a ternary system alloy which consists of copper, cobalt, and nickel are formed on this primary particle layer.
More preferably, the average particle size of the primary particle layer is 0.25 to 0.45 μm, and the average particle size of the secondary particle layer is 0.05 to 0.25 μm.

Moreover, the following processes can be used as a rust prevention process or a chromate process.
<Ni-Co plating>: Ni-Co alloy plating (Liquid composition) Co: 1 to 20 g / L, Ni: 1 to 20 g / L
(PH) 1.5 to 3.5
(Liquid temperature) 30-80 ° C
(Current density) 1-20 A / dm ²
(Energization time) 0.5-4 seconds

<Zn—Ni plating>: Zn—Ni alloy plating (liquid composition) Zn: 10 to 30 g / L, Ni: 1 to 10 g / L
(PH) 3-4
(Liquid temperature) 40-50 ° C
(Current density) 0.5 to 5 A / dm ²
(Energization time) 1-3 seconds

<Ni-Mo plating>: Ni-Mo alloy plating (liquid composition) Nickel sulfate: 270-280 g / L, nickel chloride: 35-45 g / L, nickel acetate: 10-20 g / L, molybdenum (added as sodium molybdate) ): 0.1-10 g / L, trisodium citrate: 15-25 g / L, brightener: saccharin, butynediol, sodium dodecyl sulfate: 55-75 ppm
(PH) 4-6
(Liquid temperature) 55-65 degreeC
(Current density) 1 to 11 A / dm ²
(Energization time) 1 to 20 seconds

<Cu-Zn plating>: Cu-Zn alloy plating (Liquid composition) NaCN: 10-30 g / L, NaOH: 40-100 g / L, Cu: 60-120 g / L, Zn: 1-10 g / L
(Liquid temperature) 60-80 ° C
(Current density) 1-10 A / dm ²
(Energization time) 1 to 10 seconds

<Electrolytic chromate>
(Liquid composition) Chromic anhydride, chromic acid, or potassium dichromate: 1 to 10 g / L, zinc (added in the form of zinc sulfate when added): 0 to 5 g / L
(PH) 0.5 to 10
(Liquid temperature) 40-60 ° C
(Current density) 0.1-2.6 A / dm ²
(Coulomb amount) 0.5 to 90 As / dm ²
(Energization time) 1 to 30 seconds

<Immersion chromate>
(Liquid composition) Chromic anhydride, chromic acid, or potassium dichromate: 1 to 10 g / L, zinc (added in the form of zinc sulfate when added): 0 to 5 g / L
(PH) 2 to 10
(Liquid temperature) 20-60 ° C
(Processing time) 1 to 30 seconds

  In addition, when Si and N are attached to the surface of the copper foil in the silane coupling process, aminosilane is used for the silane coupling process. And it is necessary to perform a silane coupling process by making the density | concentration of the silane coupling agent in a silane coupling process liquid higher than before (for example, 1.5 vol% or more). Further, it is necessary that the drying temperature after the silane coupling treatment is not too high and the drying time is not too long. This is because if the drying temperature is too high or the drying time is too long, the silane coupling agent present on the copper foil surface may be detached.

The drying after the silane coupling treatment is performed, for example, at a drying temperature of 90 to 110 ° C., preferably 95 ° C. to 105 ° C., and a drying time of 1 to 10 seconds, preferably 1 to 5 seconds.
In a preferred embodiment, a silane containing one or more amino groups and / or imino groups can be used as the aminosilane. The number of amino groups and imino groups contained in aminosilane can be, for example, 1 to 4, preferably 1 to 3, and more preferably 1 to 2, respectively. In a preferred embodiment, the number of amino groups and imino groups contained in aminosilane can be one each.

An aminosilane in which the total number of amino groups and imino groups contained in the aminosilane is 1, particularly monoaminosilane, 2 aminosilanes in particular, diaminosilane, and 3 aminosilanes in particular can be called triaminosilane. . Monoaminosilane and diaminosilane can be preferably used in the present invention. In a preferred embodiment, monoaminosilane containing one amino group can be used as aminosilane. In a preferred embodiment, the aminosilane may comprise at least one, for example one amino group, at the end of the molecule, preferably at the end of a linear or branched chain molecule.

  Examples of aminosilane include N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 1- Aminopropyltrimethoxysilane, 2-aminopropyltrimethoxysilane, 1,2-diaminopropyltrimethoxysilane, 3-amino-1-propenyltrimethoxysilane, 3-amino-1-propynyltrimethoxysilane, 3- Aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N- (vinylbenzyl) -2-aminoethyl- 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N Examples include-(2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, and 3- (N-phenyl) aminopropyltrimethoxysilane.

In a preferred embodiment, it is preferable to use a silane having the following structural formula I for the silane coupling treatment.
Formula I: H ₂ N—R ¹ —Si (OR ² ) ₂ (R ³ ) (Formula I)
(However, in the above formula I,
R1 is linear or branched, saturated or unsaturated, substituted or unsubstituted, cyclic or acyclic, heterocyclic or non-heterocyclic, C1-C12 hydrocarbon. A divalent group,
R2 is a C1-C5 alkyl group,
R3 is a C1-C5 alkyl group or a C1-C5 alkoxy group. )

R1 is a substituted or unsubstituted C1-C12 linear saturated hydrocarbon divalent group, a substituted or unsubstituted C1-C12 branched saturated hydrocarbon divalent group, substituted or unsubstituted C1-C12 linear unsaturated hydrocarbon divalent group, substituted or unsubstituted C1-C12 branched unsaturated hydrocarbon divalent group, substituted or unsubstituted C1-C12 ring A group consisting of a divalent group of formula hydrocarbon, a substituted or unsubstituted divalent group of a C1-C12 heterocyclic hydrocarbon, a substituted or unsubstituted divalent group of a C1-C12 aromatic hydrocarbon, It is preferably a group selected from

Further, R1 _{is, - (CH 2) n -} , - (CH 2) n - (CH) m - (CH 2) j-1 -, - (CH 2) n - (CC) - (CH 2) n _{-1 -, - (CH 2)} n -NH- (CH 2) m -, - (CH 2) n -NH- (CH 2) m -NH- (CH 2) j -, - (CH 2) n _-1- (CH) NH _2- (CH ₂ ) _m-1 -,-(CH ₂ ) _n-1- (CH) NH _2- (CH ₂ ) _m-1 -NH- (CH ₂ ) _j- It is preferable that the group is a group selected from the group consisting of (where n, m, and j are integers of 1 or more).
R1 is preferably — (CH ₂ ) _n — or — (CH ₂ ) _n —NH— (CH ₂ ) _m —.
It is preferable that n, m and j are each independently 1, 2 or 3.
R2 is preferably a methyl group or an ethyl group.
R3 is preferably a methyl group, an ethyl group, a methoxy group or an ethoxy group.

In another embodiment, a layer containing Si and N may be provided on the surface of the copper foil by dry plating such as sputtering, CVD, and PDV. And you may heat at 150-250 degreeC after that for 1 second-300 seconds. This is because Si and N existing in the surface layer are diffused to the copper foil side by heating, so that the concentration of Si and N on the surface of the copper foil can be easily controlled within a predetermined range.

An example of sputtering conditions is shown below.
(Target): Si 15 to 65 mass%, N25 to 55 mass%, and the total of Si concentration and N concentration is 50 mass% or more. The balance may be any element.
(Device) Sputtering device manufactured by ULVAC, Inc. (Output) DC50W
(Argon pressure) 0.2 Pa

Hereinafter, the present invention will be described by way of examples. In addition, a present Example shows a suitable example, This invention is not limited to these Examples. Accordingly, all modifications and other examples or aspects included in the technical idea of the present invention are included in the present invention. For comparison with the present invention, a comparative example is also shown.

Example 1
An ingot in which 1200 ppm of Sn was added to oxygen-free copper was melted, and the ingot was hot-rolled from 900 ° C. to obtain a plate having a thickness of 10 mm. Then, cold rolling and annealing were repeated, and finally cold rolled into a 9 μm thick copper foil. The surface roughness of the rolled copper foil was Rz 0.63 μm.

Next, Ni plating was implemented on the said rolled copper foil on the following conditions (roughening process was not implemented).
The balance of the Ni plating solution is water. Further, the rest of the liquid used in the roughening treatment, plating, silane treatment, heat resistance treatment, rust prevention treatment and the like described in the present application was water unless otherwise specified.
Ni ion: 10-40 g / L
Temperature: 30-70 ° C
Current density: 1-9 A / dm ²
Plating time: 0.1 to 3.0 seconds pH: 1.0 to 5.0

Next, an immersion chromate treatment was performed on the rolled copper foil plated with Ni under the following conditions.
_{K 2 Cr 2 O 7: 1~10g} / L
Temperature: 20-60 ° C
Processing time: 1-5 seconds

Next, the silane coupling treatment shown in Table 1 was performed.
Silane type: N-2- (aminoethyl) -3-aminopropyltrimethoxysilane Silane concentration: 1.5 vol%
Temperature: 10-60 ° C
Treatment time: 1-5 seconds Drying after silane treatment: 100 ° C x 3 seconds

  As a result, the copper foil surface roughness Rz (ten-point average roughness) after the silane coupling treatment was 0.63 μm. Rz was measured using a contact roughness meter Surfcorder SE-3C stylus-type roughness meter manufactured by Kosaka Laboratory Co., Ltd. according to JIS B0601-1982. Regarding the Si concentration and the N concentration on the copper foil surface, the XP concentration was measured by XPS survey, the Si concentration was 2.2%, the N concentration was 5.0%, and the high frequency characteristics were also good. Note that the Si concentration and N concentration measured by XPS survey measurement are atomic concentrations (atom%). In addition, when Si and N are detected by this measurement, it can determine with the silane coupling process layer by aminosilane existing in surface treatment copper foil.

Since the measurement methods (evaluation methods) of the Si concentration and the N concentration on the copper foil surface in the following examples and comparative examples are carried out in the same manner, this operation method is described in order to avoid complications. Will be omitted.
The above results achieved the conditions of the present invention that the Si concentration was 2.0% or more and the N concentration was 2.0% or more in the XPS survey measurement on the copper foil surface.

The silane-treated rolled copper foil thus produced was bonded to a resin of a liquid crystal polymer (Kuraray, Vecstar CT-Z) having a thickness of 50 μm by a press. The 90-degree peel strength was measured using the sample thus obtained.
The peel strength is when the circuit width is 3 mm and the resin and the copper foil are peeled off at an angle of 90 degrees at a speed of 50 mm / min. It measured twice and it was set as the average value.

The measurement of the peel strength is based on JIS C6471-1995 (hereinafter the same). As a result, the 90 degree peel strength was 0.32 kg / cm. The results are shown in Table 1. As shown in Example 1, it can be seen that the surface-treated rolled copper foil of Example 1 has industrially sufficient surface performance as a material for a high-frequency circuit board.

Further, after bonding the copper foil to a 50 μm liquid crystal polymer, a microstrip line structure was formed in order to examine high frequency characteristics. At this time, the circuit was formed so that the characteristic impedance was 50Ω. Using this circuit, transmission loss was measured, and when the transmission loss at a frequency of 30 GHz was smaller than −0.6, the high frequency characteristic was expressed as “◎”.
Further, −0.6 to −0.8 is indicated by “◯”, −0.8 to −1.2 is indicated by “Δ”, and × is indicated when the transmission loss is larger than −1.2. In addition, this measured value is shown as reference and does not limit the range.

(Example 2)
The silane treatment conditions in Example 1 were changed (silane concentration was 1.7 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.61 μm.

As in Example 1, the Si concentration and the N concentration on the copper foil surface were determined. As a result, the Si concentration was 3.7%, the N concentration was 8.5%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. Furthermore, the high frequency characteristics were also good.
As a result, a 90 degree peel strength of 0.48 kg / cm was obtained. These are shown in Table 1. As shown in Example 2, it can be seen that the surface-treated rolled copper foil of Example 2 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 3)
The silane treatment conditions in Example 1 were changed (silane concentration was 2.0 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.61 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 5.7%, the N concentration was 10.7%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. Furthermore, the high frequency characteristics were also good.
As a result, a 90 degree peel strength of 0.55 kg / cm was obtained. These are shown in Table 1. As shown in Example 3, it can be seen that the surface-treated rolled copper foil of Example 3 has industrially sufficient surface performance as a material for a high-frequency circuit board.

Example 4
The silane treatment conditions in Example 1 were changed (silane concentration: 3.0 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.67 μm.

As in Example 1, the Si concentration and the N concentration on the copper foil surface were determined. As a result, the Si concentration was 5.5%, the N concentration was 10.1%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. Furthermore, the high frequency characteristics were also good.
As a result, a 90 degree peel strength of 0.63 kg / cm was obtained. These are shown in Table 1. As shown in Example 4, it can be seen that the surface-treated rolled copper foil of Example 4 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 5)
The silane treatment conditions in Example 1 were changed (silane concentration 4.0 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.65 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were determined. As a result, the Si concentration was 6.6%, the N concentration was 10.8%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. Furthermore, the high frequency characteristics were also good.
As a result, a 90 degree peel strength of 0.63 kg / cm was obtained. These are shown in Table 1. As shown in Example 5, it can be seen that the surface-treated rolled copper foil of Example 5 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 6)
The silane treatment conditions in Example 1 were changed (silane concentration was 5.0 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.61 μm.

As in Example 1, the Si concentration and the N concentration on the copper foil surface were determined. As a result, the Si concentration was 8.5%, the N concentration was 14.1%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. Furthermore, the high frequency characteristics were also good.
As a result, a 90 degree peel strength of 0.77 kg / cm was obtained. These are shown in Table 1. As shown in Example 6, it can be seen that the surface-treated rolled copper foil of Example 6 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 7)
The conditions for silane treatment in Example 1 were changed (silane concentration was 6.5 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.60 μm.

As in Example 1, the Si concentration and the N concentration on the copper foil surface were determined. As a result, the Si concentration was 9.0%, the N concentration was 12.1%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. Furthermore, the high frequency characteristics were also good.
As a result, a 90 degree peel strength of 0.83 kg / cm was obtained. These are shown in Table 1. As shown in Example 7, it can be seen that the surface-treated rolled copper foil of Example 7 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 8)
Roughening treatment was performed before nickel plating in Example 1, heat treatment and rust prevention treatment were performed thereafter, and the silane treatment conditions were changed (silane concentration was 5.0 vol%). Other conditions were the same as in Example 1. (That is, the rolled copper foil of Example 1 which was cold-rolled to a thickness of 9 μm was subjected to roughening treatment, heat and rust prevention treatment, immersion chromate treatment, and silane treatment. Nickel plating was not performed.) As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.90 μm. An example of roughening treatment conditions is given below. In this example, roughening treatment (roughening plating) was performed under the following plating conditions.
In addition, this plating condition shows a suitable example to the last, and even if it is plating conditions other than displaying below, there is no problem.

(Copper primary particle plating conditions)
Liquid composition: Copper 10-20 g / L, sulfuric acid 50-100 g / L
Liquid temperature: 25-50 degreeC
Current density: 1 to 58 A / dm ²
Plating time: 0.1 to 10 seconds

(Plating conditions for secondary particles)
Liquid composition: Copper 10-20 g / L, nickel 5-15 g / L, cobalt 5-15 g / L
pH: 2-3
Liquid temperature: 30-50 degreeC
Current density: 24 to 50 A / dm ²
Plating time: 0.5-4 seconds

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were determined. As a result, the Si concentration was 7.2%, the N concentration was 15.2%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. Furthermore, although it was a little inferior to Examples 1-7, the high frequency characteristic was also favorable.
As a result, a 90 degree peel strength of 0.95 kg / cm was obtained. These are shown in Table 1. As shown in Example 8, it can be seen that the surface-treated rolled copper foil of Example 8 has industrially sufficient surface performance as a material for a high-frequency circuit board.

Example 9
A roughening treatment was performed before the nickel plating in Example 1, followed by heat resistance and rust prevention treatment, and the silane treatment conditions were changed (silane concentration was 7.5 vol%). Other conditions were the same as in Example 1. (That is, the rolled copper foil of Example 1 which was cold-rolled to a thickness of 9 μm was subjected to roughening treatment, heat and rust prevention treatment, immersion chromate treatment, and silane treatment. Nickel plating was not performed.) As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.92 μm. In this example, roughening treatment (roughening plating) was performed under the same plating conditions as in Example 8.

As in Example 1, the Si concentration and the N concentration on the copper foil surface were determined. As a result, the Si concentration was 9.9%, the N concentration was 22.4%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. Furthermore, although it was a little inferior to Examples 1-7, the high frequency characteristic was also favorable.
As a result, 90 degree peel strength was 1.13 kg / cm. These are shown in Table 1. As shown in Example 9, it can be seen that the surface-treated rolled copper foil of Example 9 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 10)
A roughening treatment was performed before the nickel plating in Example 1, followed by heat resistance and rust prevention treatment, and the silane treatment conditions were changed (silane concentration was 7.5 vol%). Other conditions were the same as in Example 1. (That is, the rolled copper foil of Example 1 which was cold-rolled to a thickness of 9 μm was subjected to roughening treatment, heat and rust prevention treatment, immersion chromate treatment, and silane treatment. Nickel plating was not performed.) As a result, the copper foil surface roughness Rz after the silane coupling treatment was 1.48 μm.

As in Example 1, the Si concentration and the N concentration on the copper foil surface were determined. As a result, the Si concentration was 14.6%, the N concentration was 25.3%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. Furthermore, although somewhat inferior to Examples 1-7, the high frequency characteristics are also at a normal level and are not particularly problematic.
As a result, a 90-degree peel strength of 1.31 kg / cm was obtained. These are shown in Table 1. As shown in Example 10, it can be seen that the surface-treated rolled copper foil of Example 10 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 11)
The type and conditions of the silane treatment in Example 1 were changed (N-2-aminoethyl-3-aminopropylmethyldimethoxysilane, silane concentration was 5.0 vol%), and other conditions were the same as in Example 1. did. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.62 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 10.1%, the N concentration was 19.8%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. Furthermore, the high frequency characteristics were also good.
As a result, a 90 degree peel strength of 0.71 kg / cm was obtained. These are shown in Table 1. As shown in Example 11, it can be seen that the surface-treated rolled copper foil of Example 11 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 12)
The type and conditions of silane treatment in Example 1 were changed (3-aminopropylmethoxysilane, silane concentration was 7.0 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.65 μm.

As in Example 1, the Si concentration and the N concentration on the copper foil surface were determined. As a result, the Si concentration was 12.3%, the N concentration was 11.9%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. Furthermore, the high frequency characteristics were also good.
As a result, a 90 degree peel strength of 0.81 kg / cm was obtained. These are shown in Table 1. As shown in the present Example 12, it turns out that the surface-treated rolled copper foil of Example 12 has industrially sufficient surface performance as a raw material of the circuit board for high frequency.

(Example 13)
The silane treatment type and conditions in Example 1 were changed (3-triethoxysilyl-N-1, 3dimethyl-butylidenepropylamine, silane concentration 5.5 vol%), and other conditions were as in Example 1. And the same. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.64 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 8.3%, the N concentration was 8.5%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. Furthermore, the high frequency characteristics were also good.
As a result, a 90 degree peel strength of 0.71 kg / cm was obtained. These are shown in Table 1. As shown in Example 13, it can be seen that the surface-treated rolled copper foil of Example 13 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 14)
The type and conditions of the silane treatment in Example 1 were changed (N-phenyl-3-aminopropylmethoxysilane, the silane concentration was 7.5 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.60 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 18.5%, the N concentration was 16.5%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. Furthermore, the high frequency characteristics were also good.
As a result, a 90 degree peel strength of 0.79 kg / cm was obtained. These are shown in Table 1. As shown in this Example 14, it turns out that the surface-treated rolled copper foil of Example 14 has industrially sufficient surface performance as a raw material of the high frequency circuit board.

(Comparative Example 1)
The silane treatment conditions in Example 1 were changed (silane concentration 0.5 vol%), and 90 degree peel strength was measured in the same manner. Other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.60 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 1.1%, the N concentration was 3.3%, and the Si concentration was 2.0% or more. It was outside the scope of the present invention that the N concentration was 2.0% or more.
As a result, the 90 degree peel strength was as low as 0.11 kg / cm. These are shown in Table 1. As shown in Comparative Example 1, the surface-treated rolled copper foil of Comparative Example 1 could not have industrially sufficient surface performance as a material for a high-frequency circuit board.

(Comparative Example 2)
The silane treatment conditions in Example 1 were changed (silane concentration was 1.0 vol%), and 90 degree peel strength was measured in the same manner. Other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.61 μm.

As in Example 1, the Si concentration and the N concentration on the copper foil surface were determined. As a result, the Si concentration was 1.4%, the N concentration was 3.5%, and the Si concentration was 2.0% or more. It was outside the scope of the present invention that the N concentration was 2.0% or more.
As a result, the 90 degree peel strength was as low as 0.12 kg / cm. These are shown in Table 1. As shown in Comparative Example 2, the surface-treated rolled copper foil of Comparative Example 2 could not have industrially sufficient surface performance as a material for a high-frequency circuit board.

(Comparative Example 3)
The silane treatment in Example 1 was not performed. Accordingly, there is no Si or N on the surface of the copper foil. And 90 degree | times peel strength was measured similarly. Other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.61 μm.

Since neither Si nor N on the copper foil surface was present, the Si concentration on the copper foil surface was 2.0% or more, and the N concentration was 2.0% or more, which was outside the scope of the present invention.
As a result, the 90 degree peel strength was extremely low at 0.03 kg / cm. These are shown in Table 1. As shown in Comparative Example 3, the rolled copper foil in which Si and N do not exist on the copper foil surface could not have industrially sufficient surface performance as a material for the high-frequency circuit board.

(Comparative Example 4)
Roughening treatment was performed before nickel plating in Example 1, and then heat resistance and rust prevention treatment was performed, but silane treatment was not performed. (That is, the rolled copper foil of Example 1 which was cold-rolled to a thickness of 9 μm was subjected to roughening treatment, heat resistance and rust prevention treatment, and immersion chromate treatment. Nickel plating was not performed.) Therefore, the copper foil There is no Si or N on the surface. And 90 degree | times peel strength was measured similarly. Other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.92 μm. In this example, roughening treatment (roughening plating) was performed under the same plating conditions as in Example 8.

Since neither Si nor N on the copper foil surface was present, the Si concentration on the copper foil surface was 2.0% or more, and the N concentration was 2.0% or more, which was outside the scope of the present invention.
As a result, the 90 degree peel strength was as low as 0.32 kg / cm. These are shown in Table 1. Compared with Examples 8 and 9, the rolled copper foil in which Si and N are not present on the copper foil surface could not have industrially sufficient surface performance as a material for the circuit board for high frequency.

(Comparative Example 5)
Roughening treatment was performed before nickel plating in Example 1, and then heat resistance and rust prevention treatment was performed, but silane treatment was not performed. (That is, the rolled copper foil of Example 1 which was cold-rolled to a thickness of 9 μm was subjected to roughening treatment, heat resistance and rust prevention treatment, and immersion chromate treatment. Nickel plating was not performed.) Therefore, the copper foil There is no Si or N on the surface. And 90 degree | times peel strength was measured similarly. Other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 1.53 μm. In this example, roughening treatment (roughening plating) was performed under the same plating conditions as in Example 10.

Since neither Si nor N on the copper foil surface was present, the Si concentration on the copper foil surface was 2.0% or more, and the N concentration was 2.0% or more, which was outside the scope of the present invention.
As a result, the 90-degree peel strength was 0.66 kg / cm. These are shown in Table 1. Compared with Example 10, it could not be said that the rolled copper foil in which Si and N are not present on the surface of the copper foil has an industrially optimum surface performance as a material for a high-frequency circuit board.

(Comparative Example 6)
Roughening treatment was performed before nickel plating in Example 1, and then heat resistance and rust prevention treatment was performed, but silane treatment was not performed. (That is, the rolled copper foil of Example 1 which was cold-rolled to a thickness of 9 μm was subjected to roughening treatment, heat resistance and rust prevention treatment, and immersion chromate treatment. Nickel plating was not performed.) Therefore, the copper foil There is no Si or N on the surface. And 90 degree | times peel strength was measured similarly. Other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 3.21 μm.

Since neither Si nor N on the copper foil surface was present, the Si concentration on the copper foil surface was 2.0% or more, and the N concentration was 2.0% or more, which was outside the scope of the present invention.
As a result, the 90-degree peel strength was 0.89 kg / cm. These are shown in Table 1. Compared with other comparative examples, the peel strength is high, but this is a physical effect due to the rough surface roughness. However, as described above, since the loss is large due to the skin effect when the roughness is large, this copper Foil could not be said to have industrially optimal surface performance as a material for high-frequency circuit boards.

(Comparative Example 7)
Roughening treatment was performed before nickel plating in Example 1, and then heat resistance and rust prevention treatment was performed, but the conditions for silane treatment were further changed (silane concentration was 10.0 vol%). Other conditions were the same as in Example 1. (That is, the rolled copper foil of Example 1 which was cold-rolled to a thickness of 9 μm was subjected to roughening treatment, heat and rust prevention treatment, immersion chromate treatment, and silane treatment. Nickel plating was not performed.) As a result, the copper foil surface roughness Rz after the silane coupling treatment was 1.51 μm. In this example, roughening treatment (roughening plating) was performed under the same plating conditions as in Example 10.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were determined. As a result, the Si concentration was 20.6%, the N concentration was 40.1%, and the Si concentration was 2.0% or more. Although it was within the scope of the present invention that the N concentration was 2.0% or more, the presence of a large amount had a problem, and foaming occurred during lamination with a liquid crystal polymer (LCP). Therefore, the peel strength is not measured for this copper foil. These are shown in Table 1. As shown in Comparative Example 7, the surface-treated rolled copper foil of Comparative Example 7 could not have industrially sufficient surface performance as a material for a high-frequency circuit board.

(Comparative Example 8)
The silane treatment conditions in Example 1 were changed (glycidoxypropyltrimethoxysilane was used and the concentration was 1.5 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.62 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were determined. As a result, the Si concentration was 2.2%, the N concentration was 0.0%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90 degree peel strength was as low as 0.13 kg / cm. These are shown in Table 1. As shown in Comparative Example 8, the surface-treated rolled copper foil of Comparative Example 8 could not have industrially sufficient surface performance as a material for a high-frequency circuit board.

(Comparative Example 9)
The silane treatment conditions in Example 1 were changed (glycidoxypropyltrimethoxysilane was used and the concentration was 5.0 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.63 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 9.5%, the N concentration was 0.0%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90 degree peel strength was as low as 0.19 kg / cm. These are shown in Table 1. As shown in Comparative Example 9, the surface-treated rolled copper foil of Comparative Example 9 could not have industrially sufficient surface performance as a material for a high-frequency circuit board.

(Comparative Example 10)
The silane treatment conditions in Example 1 were changed (3-methacryloxypropyltrimethoxysilane was used and the concentration was 2.0 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.67 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 5.2%, the N concentration was 0.0%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90 degree peel strength was extremely low at 0.04 kg / cm. These are shown in Table 1. As shown in Comparative Example 10, the surface-treated rolled copper foil of Comparative Example 10 could not have industrially sufficient surface performance as a material for a high-frequency circuit board.

(Comparative Example 11)
The conditions for silane treatment in Example 1 were changed (vinyltrimethoxysilane was used and the concentration was 0.5 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.65 μm.

As in Example 1, the Si concentration and the N concentration on the copper foil surface were determined. As a result, the Si concentration was 1.4%, the N concentration was 0.0%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90 degree peel strength was extremely low at 0.07 kg / cm. These are shown in Table 1. As shown in Comparative Example 11, the surface-treated rolled copper foil of Comparative Example 11 could not have industrially sufficient surface performance as a material for a high-frequency circuit board.

(Comparative Example 12)
The silane treatment conditions in Example 1 were changed (vinyltrimethoxysilane was used and the concentration was 2.0 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.65 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 5.8%, the N concentration was 0.0%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90 degree peel strength was extremely low at 0.09 kg / cm. These are shown in Table 1. As shown in Comparative Example 12, the surface-treated rolled copper foil of Comparative Example 12 could not have industrially sufficient surface performance as a material for a high-frequency circuit board.

(Comparative Example 13)
The conditions for silane treatment in Example 1 were changed (vinyltrimethoxysilane was used and the concentration was 5.0 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.65 μm.

As in Example 1, the Si concentration and the N concentration on the copper foil surface were determined. As a result, the Si concentration was 11.1%, the N concentration was 0.0%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90 degree peel strength was extremely low at 0.11 kg / cm. These are shown in Table 1. As shown in Comparative Example 13, the surface-treated rolled copper foil of Comparative Example 13 could not have industrially sufficient surface performance as a material for a high-frequency circuit board.

(Comparative Example 14)
The conditions for the silane treatment in Example 1 were changed (3-mercaptopropyltrimethoxysilane was used and the concentration was 2.0 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.64 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were determined. As a result, the Si concentration was 5.6%, the N concentration was 0.0%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90 degree peel strength was extremely low at 0.07 kg / cm. These are shown in Table 1. As shown in Comparative Example 14, the surface-treated rolled copper foil of Comparative Example 14 could not have industrially sufficient surface performance as a material for a high-frequency circuit board.

(Comparative Example 15)
The conditions for silane treatment in Example 1 were changed (tetramethoxysilane was used and the concentration was 2.0 vol%), and other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.67 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 5.7%, the N concentration was 0.0%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90 degree peel strength was extremely low at 0.07 kg / cm. These are shown in Table 1. As shown in Comparative Example 15, the surface-treated rolled copper foil of Comparative Example 15 could not have industrially sufficient surface performance as a material for a high-frequency circuit board.

(Comparative Example 16)
The conditions for the silane treatment in Example 1 were changed (tetramethoxysilane and 3-mercaptopropyltrimethoxysilane mixed were used, and the concentration was 0.2 + 0.5 vol%). Other conditions were the same as in Example 1. did. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.64 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were determined. As a result, the Si concentration was 3.2%, the N concentration was 0.0%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90 degree peel strength was extremely low at 0.05 kg / cm. These are shown in Table 1. As shown in Comparative Example 16, the surface-treated rolled copper foil of Comparative Example 16 could not have industrially sufficient surface performance as a material for a high-frequency circuit board.

  Next, the example at the time of changing the kind of copper foil, a roughening process, a heat-resistant process, and a rust prevention process is shown. This example also includes an example in which heat treatment and / or rust prevention treatment is not performed (Examples 28, 29, 31 to 33). In this case, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane was used as the silane, and the silane concentration was 5.0 vol%. Drying after silane treatment was 100 ° C. × 3 seconds. The heat treatment is not limited as long as the heat resistance can be ensured when the copper foil and the liquid crystal polymer (LCP) are laminated.

Examples include single or alloy plating of Zn, Ni, Co, Mo, P, Cr, W or the like. In addition, the heat-resistant process layer which does not contain Zn may be sufficient. The production conditions and evaluation (peel strength) methods from Example 21 to Example 33 and Comparative Example 21 to Comparative Example 27 below are the same as in Example 1 except that they are described individually. Note that the treatment conditions for the Ni—Co plating treatment, the Zn—Ni plating treatment, the Ni—Mo plating treatment, the Cu—Zn plating treatment, the electrolytic chromate treatment, and the immersion chromate treatment were as described above. The conditions for the immersion chromate treatment were the same as in Example 1.

(Example 21)
The rolled copper foil having a plate thickness of 6 μm was subjected to a roughening treatment, and a Ni—Co plating treatment was performed as a heat treatment. Moreover, the electrolytic chromate process was performed as a rust prevention process. Further, silane treatment was performed thereon. The silane concentration was 5.0 vol%. Other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.82 μm. Table 2 shows the processing conditions.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 6.6%, the N concentration was 8.2%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved.
As a result, the 90 degree peel strength was as high as 0.88 kg / cm.
These results are shown in Table 3. As shown in Example 21, it can be seen that the surface-treated rolled copper foil of Example 21 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 22)
The rolled copper foil having a plate thickness of 12 μm was subjected to a roughening treatment, and a Zn—Ni plating treatment was carried out as a heat treatment. Moreover, the immersion chromate process as a rust prevention process was performed. Further, silane treatment was performed thereon. The silane concentration was 5.0 vol%.
Other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.90 μm. Table 2 shows the processing conditions.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were determined. As a result, the Si concentration was 6.8%, the N concentration was 9.0%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved.
As a result, the 90 degree peel strength was as high as 0.93 kg / cm. These results are shown in Table 3. As shown in Example 22, it can be seen that the surface-treated rolled copper foil of Example 22 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 23)
The rolled copper foil having a plate thickness of 35 μm was subjected to a roughening treatment, and a Ni—Mo plating treatment was performed as a heat treatment. Moreover, the immersion chromate process as a rust prevention process was performed. Further, silane treatment was performed thereon. The silane concentration was 5.0 vol%.

Other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 1.55 μm. Table 2 shows the processing conditions.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 5.5%, the N concentration was 7.3%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved.
As a result, the 90 degree peel strength was as high as 1.30 kg / cm. These results are shown in Table 3. As shown in this Example 23, it turns out that the surface-treated rolled copper foil of Example 23 has industrially sufficient surface performance as a raw material of the high frequency circuit board.

(Example 24)
The rolled copper foil having a plate thickness of 18 μm was subjected to a roughening treatment, and a Cu—Zn plating treatment was performed as a heat treatment. Moreover, the electrolytic chromate process as a rust prevention process was performed. Further, silane treatment was performed thereon. The silane concentration was 5.0 vol%.
Other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.81 μm. Table 2 shows the processing conditions.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 3.8%, the N concentration was 4.3%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved.
As a result, the 90 degree peel strength was as high as 0.85 kg / cm. These results are shown in Table 3. As shown in Example 24, it can be seen that the surface-treated rolled copper foil of Example 24 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 25)
The glossy surface of the electrolytic copper foil having a plate thickness of 18 μm was subjected to a roughening treatment, and a Ni—Co plating treatment was performed as a heat treatment. Moreover, the electrolytic chromate process as a rust prevention process was performed. Further, silane treatment was performed thereon. The silane concentration was 5.0 vol%.
Other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 1.62 μm. Table 2 shows the processing conditions.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 4.6%, the N concentration was 8.9%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved.
As a result, the 90 degree peel strength was as high as 1.29 kg / cm. These results are shown in Table 3. As shown in Example 25, it can be seen that the surface-treated electrolytic copper foil of Example 25 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 26)
The glossy surface of the electrolytic copper foil having a thickness of 5 μm was subjected to a roughening treatment, and a Zn—Ni plating treatment was performed as a heat treatment. Moreover, the immersion chromate process as a rust prevention process was performed. Further, silane treatment was performed thereon. The silane concentration was 5.0 vol%.
Other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 1.31 μm. Table 2 shows the processing conditions.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 5.2%, the N concentration was 5.9%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved.
As a result, the 90 degree peel strength was as high as 1.01 kg / cm. These results are shown in Table 3. As shown in Example 26, it can be seen that the surface-treated electrolytic copper foil of Example 26 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 27)
A roughening treatment was applied to the glossy surface of the electrolytic copper foil having a thickness of 12 μm, and a Ni—Mo plating treatment was performed as a heat treatment. Moreover, the immersion chromate process as a rust prevention process was performed. Further, silane treatment was performed thereon. The silane concentration was 5.0 vol%.
Other conditions were the same as in Example 1. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 1.42 μm. Table 2 shows the processing conditions.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 5.4%, the N concentration was 6.4%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved.
As a result, the 90 degree peel strength was as high as 1.18 kg / cm. These results are shown in Table 3. As shown in Example 27, it can be seen that the surface-treated electrolytic copper foil of Example 27 has industrially sufficient surface performance as a material for a high-frequency circuit board.

Next, the example at the time of changing the kind of copper foil, a roughening process, heat-resistant process, and a rust prevention process is shown. In this case, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane was used as the silane, and the silane concentration was 0.5 vol%. Drying after silane treatment was 100 ° C. × 3 seconds.
Further, for Comparative Examples 21 to 27, the types of base materials and the conditions of the roughening treatment, the rust prevention treatment, and the chromate treatment are the same conditions as in Examples 21 to 27, and only the silane concentration is changed. An example of (necessarily changing the adhesion amount of Si and N) is shown.

(Example 28)
A rolled copper foil having a thickness of 9 μm (tough pitch copper (JIS H3100 alloy number C1100) manufactured by JX Nippon Mining & Metals Co., Ltd.) was subjected to a roughening treatment under the following conditions, followed by a silane coupling treatment. In addition, the roughening process was performed by performing the process which provides the primary particle of copper on the surface of the said rolled copper foil, and then performs the process which provides a secondary particle. Further, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane was used as the silane-treated silane, and the silane concentration was 5.0 vol%. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.91 μm.

<Roughening treatment conditions>
(Copper primary particle plating conditions)
Liquid composition: Copper 10-20 g / L, sulfuric acid 50-100 g / L
Liquid temperature: 25-50 degreeC
Current density: 1 to 58 A / dm ²
Plating time: 0.1 to 10 seconds

(Plating conditions for secondary particles)
Liquid composition: Copper 10-20 g / L, nickel 5-15 g / L, cobalt 5-15 g / L
pH: 2-3
Liquid temperature: 30-50 degreeC
Current density: 24 to 50 A / dm ²
Plating time: 0.5-4 seconds

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 7.3%, the N concentration was 15.1%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. As a result, a 90 degree peel strength of 0.95 kg / cm was obtained.

Moreover, the surface of the surface-treated copper foil after silane treatment was photographed using a scanning electron microscope (SEM). And the particle | grains of the roughening process were observed using the said photograph. As a result, the average particle diameter of the primary particle layer of copper was 0.25 to 0.45 μm, and the average particle diameter of the secondary particle layer was 0.05 to 0.25 μm. In addition, the diameter of the smallest circle surrounding the particles was measured as the particle diameter, and the average particle diameter was calculated.
These are shown in Table 3. As shown in Example 28, it can be seen that the surface-treated copper foil of Example 28 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 29)
A rolled copper foil with a thickness of 9 μm (tough pitch copper (JIS H3100 alloy number C1100) manufactured by JIS Nippon Mining & Metals Co., Ltd.) is subjected to a roughening treatment under the following conditions, followed by an electrolytic chromate treatment, and then a silane coupling treatment. went. In addition, the roughening process was performed by performing the process which provides the primary particle of copper on the surface of the said rolled copper foil, and then performs the process which provides a secondary particle. Further, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane was used as the silane-treated silane, and the silane concentration was 5.0 vol%. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.91 μm.

<Roughening treatment conditions>
(Copper primary particle plating conditions)
Liquid composition: Copper 10-20 g / L, sulfuric acid 50-100 g / L
Liquid temperature: 25-50 degreeC
Current density: 1 to 58 A / dm ²
Plating time: 0.1 to 10 seconds

(Plating conditions for secondary particles)
Liquid composition: Copper 10-20 g / L, nickel 5-15 g / L, cobalt 5-15 g / L
pH: 2-3
Liquid temperature: 30-50 degreeC
Current density: 24 to 50 A / dm ²
Plating time: 0.5-4 seconds

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 7.5%, the N concentration was 15.4%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. As a result, a 90 degree peel strength of 0.96 kg / cm was obtained.

Moreover, the surface of the surface-treated copper foil after silane treatment was photographed using a scanning electron microscope (SEM). And the particle | grains of the roughening process were observed using the said photograph. As a result, the average particle diameter of the primary particle layer of copper was 0.25 to 0.45 μm, and the average particle diameter of the secondary particle layer was 0.05 to 0.25 μm. In addition, the diameter of the smallest circle surrounding the particles was measured as the particle diameter, and the average particle diameter was calculated.
These are shown in Table 3. As shown in Example 29, it can be seen that the surface-treated copper foil of Example 29 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 30)
A rolled copper foil with a thickness of 9 μm (tough pitch copper (JIS H3100 alloy number C1100) manufactured by JIS Nippon Mining & Metals Co., Ltd.) is subjected to a roughening treatment under the following conditions, followed by a Ni—Co plating treatment, followed by an electrolytic chromate treatment. After that, silane coupling treatment was performed. In addition, the said roughening process was performed by performing the process which provides the primary particle of copper on the surface of the said rolled copper foil, and then performs the process which provides a secondary particle. Further, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane was used as the silane-treated silane, and the silane concentration was 5.0 vol%. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.90 μm.

<Roughening treatment conditions>
(Copper primary particle plating conditions)
Liquid composition: Copper 10-20 g / L, sulfuric acid 50-100 g / L
Liquid temperature: 25-50 degreeC
Current density: 1 to 58 A / dm ²
Plating time: 0.1 to 10 seconds

(Plating conditions for secondary particles)
Liquid composition: Copper 10-20 g / L, nickel 5-15 g / L, cobalt 5-15 g / L
pH: 2-3
Liquid temperature: 30-50 degreeC
Current density: 24 to 50 A / dm ²
Plating time: 0.5-4 seconds

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 7.6%, the N concentration was 15.6%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. As a result, a 90 degree peel strength of 0.96 kg / cm was obtained.

Moreover, the surface of the surface-treated copper foil after silane treatment was photographed using a scanning electron microscope (SEM). And the particle | grains of the roughening process were observed using the said photograph. As a result, the average particle diameter of the primary particle layer of copper was 0.25 to 0.45 μm, and the average particle diameter of the secondary particle layer was 0.05 to 0.25 μm. In addition, the diameter of the smallest circle surrounding the particles was measured as the particle diameter, and the average particle diameter was calculated.
These are shown in Table 3. As shown in Example 30, it can be seen that the surface-treated copper foil of Example 30 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 31)
Electrolytic chromate treatment was performed on a rolled copper foil having a thickness of 12 μm (Tough pitch copper (JIS H3100 alloy number C1100) manufactured by JIS Nippon Mining & Metals Co., Ltd.), followed by silane coupling treatment. N-2- (aminoethyl) -3-aminopropyltrimethoxysilane was used as the silane-treated silane, and the silane concentration was 5.0 vol%. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.62 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 8.4%, the N concentration was 14.0%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. As a result, a 90 degree peel strength of 0.67 kg / cm was obtained.
These are shown in Table 3. As shown in Example 31, it can be seen that the surface-treated copper foil of Example 31 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 32)
A silane coupling treatment was performed on a high gloss rolled copper foil having a thickness of 12 μm (tough pitch copper (JIS H3100 alloy number C1100) manufactured by JX Nippon Mining & Metals Co., Ltd., 60 ° specular gloss of 500% or more). N-2- (aminoethyl) -3-aminopropyltrimethoxysilane was used as the silane-treated silane, and the silane concentration was 5.0 vol%. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.31 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 8.2%, the N concentration was 13.8%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. As a result, a 90 degree peel strength of 0.61 kg / cm was obtained.
These are shown in Table 3. As shown in Example 32, it can be seen that the surface-treated copper foil of Example 32 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Example 33)
A SiN film is formed on a high gloss rolled copper foil having a thickness of 12 μm (tough pitch copper (JIS H3100 alloy number C1100) manufactured by JIS Nippon Mining & Metals Co., Ltd., 60 ° specular gloss of 500% or more) under the following sputtering conditions, and then 200 ° C. For 5 minutes. The copper foil surface roughness Rz after sputtering was 0.30 μm.
(Target): Si 59.5 mass% or more, N39.5 mass% or more.
(Device) Sputtering device manufactured by ULVAC, Inc. (Output) DC50W
(Argon pressure) 0.2 Pa

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 8.5%, the N concentration was 11.3%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was achieved. As a result, a 90 degree peel strength of 0.65 kg / cm was obtained.
These are shown in Table 3. As shown in Example 33, it can be seen that the surface-treated copper foil of Example 33 has industrially sufficient surface performance as a material for a high-frequency circuit board.

(Comparative Example 21)
The rolled copper foil having a plate thickness of 6 μm was subjected to a roughening treatment, and a Ni—Co plating treatment was performed as a heat treatment. Moreover, the electrolytic chromate process was performed as a rust prevention process. Further, silane treatment was performed thereon. The silane concentration was 0.5 vol%. The silane concentration of 0.5 vol% is a concentration generally set by silane treatment. Moreover, since the specific gravity of silane is about 1.0, 0.5 vol% means about 0.5 wt%.
Other conditions were the same as in Example 1. Table 2 shows the processing conditions. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.82 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were determined. As a result, the Si concentration was 0.3%, the N concentration was 0.4%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90-degree peel strength decreased to 0.29 kg / cm. These results are shown in Table 3. As shown in Comparative Example 21, the surface-treated rolled copper foil of Comparative Example 21 did not have the industrially sufficient surface performance expected as a material for a high-frequency circuit board.

(Comparative Example 22)
The rolled copper foil having a plate thickness of 12 μm was subjected to a roughening treatment, and a Zn—Ni plating treatment was carried out as a heat treatment. Moreover, the immersion chromate process as a rust prevention process was performed. Further, silane treatment was performed thereon. The silane concentration was 0.5 vol%.
Other conditions were the same as in Example 1. Table 2 shows the processing conditions. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.90 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were determined. As a result, the Si concentration was 0.3%, the N concentration was 0.5%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90-degree peel strength was 0.32 kg / cm, which was reduced. These results are shown in Table 3. As shown in Comparative Example 22, the surface-treated rolled copper foil of Comparative Example 22 did not have the industrially sufficient surface performance expected as a material for the high-frequency circuit board.

(Comparative Example 23)
The rolled copper foil having a plate thickness of 35 μm was subjected to a roughening treatment, and a Ni—Mo plating treatment was performed as a heat treatment. Moreover, the immersion chromate process as a rust prevention process was performed. Further, silane treatment was performed thereon. The silane concentration was 0.5 vol%.
Other conditions were the same as in Example 1. Table 2 shows the processing conditions. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 1.55 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were determined. As a result, the Si concentration was 0.7%, the N concentration was 0.8%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90-degree peel strength decreased to 0.70 kg / cm. These results are shown in Table 3. As shown in Comparative Example 23, the surface-treated rolled copper foil of Comparative Example 23 did not have the industrially sufficient surface performance expected as a material for the high-frequency circuit board.

(Comparative Example 24)
The rolled copper foil having a plate thickness of 18 μm was subjected to a roughening treatment, and a Cu—Zn plating treatment was performed as a heat treatment. Moreover, the electrolytic chromate process as a rust prevention process was performed. Further, silane treatment was performed thereon. The silane concentration was 0.5 vol%.
Other conditions were the same as in Example 1. Table 2 shows the processing conditions. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.81 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 0.4%, the N concentration was 0.7%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90-degree peel strength was significantly reduced to 0.30 kg / cm. These results are shown in Table 3. As shown in Comparative Example 24, the surface-treated rolled copper foil of Comparative Example 24 did not have industrially sufficient surface performance as a material for a high-frequency circuit board.

(Comparative Example 25)
The glossy surface of the electrolytic copper foil having a plate thickness of 18 μm was subjected to a roughening treatment, and a Ni—Co plating treatment was performed as a heat treatment. Moreover, the electrolytic chromate process as a rust prevention process was performed. Further, silane treatment was performed thereon. The silane concentration was 0.5 vol%.
Other conditions were the same as in Example 1. Table 2 shows the processing conditions. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 1.62 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 1.0%, the N concentration was 1.1%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90-degree peel strength decreased to 0.65 kg / cm. These results are shown in Table 3. As shown in Comparative Example 25, the surface-treated electrolytic copper foil of Comparative Example 25 did not have the industrially sufficient surface performance expected as a material for a high-frequency circuit board.

(Comparative Example 26)
The electrolytic copper foil having a plate thickness of 5 μm was subjected to a roughening treatment, and a Zn—Ni plating treatment was performed as a heat treatment. Moreover, the immersion chromate process as a rust prevention process was performed. Further, silane treatment was performed thereon. The silane concentration was 0.5 vol%.
Other conditions were the same as in Example 1. Table 2 shows the processing conditions. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 1.31 μm.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were determined. As a result, the Si concentration was 0.8%, the N concentration was 1.3%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90-degree peel strength was lowered to 0.44 kg / cm. These results are shown in Table 3. As shown in Comparative Example 26, the surface-treated electrolytic copper foil of Comparative Example 26 did not have the industrially sufficient surface performance expected as a material for a high-frequency circuit board.

(Comparative Example 27)
The electrolytic copper foil having a plate thickness of 12 μm was subjected to a roughening treatment, and a Ni—Mo plating treatment was performed as a heat treatment. Moreover, the immersion chromate process as a rust prevention process was performed. Further, silane treatment was performed thereon. The silane concentration was 0.5 vol%.
Other conditions were the same as in Example 1. Table 2 shows the processing conditions. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 1.42 μm.

As in Example 1, the Si concentration and the N concentration on the copper foil surface were determined. As a result, the Si concentration was 1.1%, the N concentration was 1.1%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90-degree peel strength decreased to 0.45 kg / cm. These results are shown in Table 3. As shown in Comparative Example 27, the surface-treated electrolytic copper foil of Comparative Example 27 did not have the industrially sufficient surface performance expected as a material for a high-frequency circuit board.

(Comparative Example 28)
The glossy surface of the electrolytic copper foil having a plate thickness of 12 μm was subjected to Ni—Zn plating treatment as a heat treatment. Moreover, the electrolytic chromate process as a rust prevention process was performed. Further, silane treatment was performed thereon. The silane concentration was 0.5 vol%.
Other conditions were the same as in Example 1. Table 2 shows the processing conditions. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.60 μm. The coating weight of Ni and Zn in this case was the 600 [mu] g / dm ² and 90 [mu] g / dm ^2, respectively.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were determined. As a result, the Si concentration was 0.7%, the N concentration was 0.9%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90 degree peel strength was as low as 0.10 kg / cm. These results are shown in Table 3. As shown in Comparative Example 28, the surface-treated electrolytic copper foil of Comparative Example 28 did not have the industrially sufficient surface performance expected as a material for a high-frequency circuit board.
When the peel strength is measured by laminating the copper foil and polyimide, it becomes 0.8 kg / cm, and it can be confirmed that the peel strength difference is large depending on the resin.

(Comparative Example 29)
The electrolytic copper foil having a plate thickness of 12 μm was subjected to a roughening treatment, and a Ni—Mo plating treatment was performed as a heat treatment. Moreover, the immersion chromate process as a rust prevention process was performed. Further, silane treatment was performed thereon. The silane concentration was 0.5 vol%.
Other conditions were the same as in Example 1. Table 2 shows the processing conditions. As a result, the copper foil surface roughness Rz after the silane coupling treatment was 0.61 μm. At this time, the adhesion amounts of Ni and Zn were 2850 μg / dm ² and 190 μg / dm ² , respectively.

As in Example 1, the Si concentration and the N concentration on the surface of the copper foil were obtained. As a result, the Si concentration was 0.9%, the N concentration was 1.3%, and the Si concentration was 2.0% or more. The condition of the present invention that the N concentration was 2.0% or more was not satisfied.
As a result, the 90 degree peel strength was as low as 0.11 kg / cm. These results are shown in Table 3. As shown in Comparative Example 29, the surface-treated electrolytic copper foil of Comparative Example 29 did not have the industrially sufficient surface performance expected as a material for the high-frequency circuit board. When the peel strength is measured by laminating the copper foil and the polyimide, it is 1.2 kg / cm, and it can be confirmed that the peel strength difference is large depending on the resin.

In the present invention, a copper foil for a high frequency circuit can be manufactured, and by applying the copper foil to a liquid crystal polymer (LCP) laminated substrate, it is possible to increase the adhesive strength (peel strength) and exceed 1 GHz. An excellent effect that a flexible printed circuit board that can be used under a high frequency can be realized is obtained, which is extremely useful industrially.

Claims (28)

A surface-treated copper foil to be bonded to a liquid crystal polymer, wherein an XPS survey measurement of the surface-treated copper foil surface has an Si concentration of 2.2 to 18.5 atom % and an N concentration of 4.3 to 25. 3 the atom% der is, the surface-treated copper foil ten-point average roughness Rz of the surface treated copper foil surface, characterized in der Rukoto below 1.62. 2. The surface-treated copper foil according to claim 1, wherein in the XPS survey measurement of the surface-treated copper foil surface, the Si concentration is 3.7 atom % or more and the N concentration is 8.5 atom % or more. . 2. The surface-treated copper foil according to claim 1, wherein in the XPS survey measurement of the surface-treated copper foil surface, the Si concentration is 5.5 atom % or more and the N concentration is 10.1 atom % or more. . 2. The surface-treated copper foil according to claim 1, wherein in the XPS survey measurement of the surface-treated copper foil surface, the Si concentration is 6.6 atom % or more and the N concentration is 10.8 atom % or more. . 2. The surface-treated copper foil according to claim 1, wherein in the XPS survey measurement of the surface-treated copper foil surface, the Si concentration is 8.5 atom % or more and the N concentration is 12.1 atom % or more. . The surface-treated copper foil according to claim 1, wherein the surface-treated copper foil has a surface roughness Rz of 0.92 μm or less. The surface-treated copper foil according to claim 1, wherein the surface-treated copper foil has a surface roughness Rz of 0.82 μm or more and 1.62 μm or less.   It is a copper foil for flexible printed wiring boards, The surface-treated copper foil as described in any one of Claims 1-7 characterized by the above-mentioned.   The surface-treated copper foil according to any one of claims 1 to 8, wherein the copper foil is a rolled copper foil or an electrolytic copper foil.   It is used for the flexible printed circuit board used under the high frequency exceeding 1 GHz, The surface-treated copper foil as described in any one of Claims 1-9 characterized by the above-mentioned.   The copper foil surface has at least one layer selected from the group consisting of a roughening treatment layer, a heat treatment treatment layer, a rust prevention treatment layer, a chromate treatment layer, and a silane coupling treatment layer. The surface-treated copper foil as described in the item.   The surface as described in any one of Claims 1-10 which has 1 or more types of layers selected from the group which consists of a heat-resistant process layer, a rust prevention process layer, a chromate process layer, and a silane coupling process layer on the copper foil surface. Treated copper foil.   A heat-resistant treatment layer or a rust prevention treatment layer is provided on the surface of the copper foil, a chromate treatment layer is provided on the heat treatment treatment layer or the rust prevention treatment layer, and a silane coupling treatment layer is provided on the chromate treatment layer. The surface-treated copper foil as described in any one of claim | item 1 -12.   It has a heat resistant treatment layer on the copper foil surface, has a rust prevention treatment layer on the heat treatment treatment layer, has a chromate treatment layer on the rust prevention treatment layer, and has a silane cup on the chromate treatment layer. The surface-treated copper foil as described in any one of Claims 1-12 which has a ring treatment layer.   The surface-treated copper foil as described in any one of Claims 1-12 which has a chromate treatment layer on the copper foil surface, and has a silane coupling treatment layer on the said chromate treatment layer.   It has a roughening process layer on the copper foil surface, has a chromate process layer on the said roughening process layer, and has a silane coupling process layer on the said chromate process layer. The surface-treated copper foil as described in the item.   It has a roughened layer on the surface of the copper foil, and has at least one layer selected from the group consisting of a rust-proof layer and a heat-resistant layer on the roughened layer, It has a chromate treatment layer on one or more sorts of layers chosen from the group which consists of a heat-resistant treatment layer, and has a silane coupling treatment layer on the chromate treatment layer. The surface-treated copper foil of description.   It has a roughened layer on the copper foil surface, a heat-resistant layer on the roughened layer, a rust-proof layer on the heat-resistant layer, and a chromate on the rust-proof layer. The surface-treated copper foil as described in any one of Claims 1-11 which has a process layer and has a silane coupling process layer on the said chromate process layer.   A copper foil surface has a roughening process layer, The said roughening process layer has a primary particle layer and a secondary particle layer on this primary particle layer, The any one of Claims 1-11 and 16-18. The surface-treated copper foil as described in the item.   The surface-treated copper foil as described in any one of Claim 11, 16-18 in which the said roughening process layer has a secondary particle layer on a primary particle layer and this primary particle layer.   The said roughening process layer has a secondary particle layer which consists of a ternary system alloy which consists of a primary particle layer of copper, and this primary particle layer which consists of copper, cobalt, and nickel, either of Claim 11, 16-20 The surface-treated copper foil according to one item.   The roughening layer has a primary particle layer of copper, and a secondary particle layer made of a ternary alloy made of copper, cobalt and nickel on the primary particle layer, and the average particle size of the primary particle layer The surface-treated copper foil according to any one of claims 11 and 16 to 21, wherein the surface-treated copper foil is 0.25 to 0.45 µm, and the average particle size of the secondary particle layer is 0.05 to 0.25 µm.   The surface-treated copper foil as described in any one of Claim 11, 16-22 which has a chromate treatment layer on the said roughening treatment layer, and has a silane coupling treatment layer on the said chromate treatment layer.   The rust prevention treatment layer is provided on the roughening treatment layer, the chromate treatment layer is provided on the rust prevention treatment layer, and the silane coupling treatment layer is provided on the chromate treatment layer. The surface-treated copper foil as described in any one of 23.   The copper clad laminated board for manufacturing a flexible printed wiring board (FPC) provided with the surface-treated copper foil in any one of Claims 1-24.   The flexible printed wiring board using the surface-treated copper foil in any one of Claims 1-24.   The flexible printed circuit board using the surface-treated copper foil in any one of Claims 1-24.   The electronic device provided with the flexible printed wiring board of Claim 26.