KR101372519B1 - Copper foil attached to carrier foil, a method for preparing the same and printed circuit board using the same - Google Patents

Abstract

An ultrathin copper foil with a carrier foil formed by sequentially stacking a carrier foil, a peeling layer and an ultrathin copper foil, the ultrathin copper foil with a carrier foil having a low reflectance with respect to light having a wavelength oscillating from a carbon dioxide gas laser, a print comprising the same A wiring board and a manufacturing method thereof are provided.

Description

Copper foil attached to carrier foil, a method for preparing the same and printed circuit board using the same}

It is related with the ultra-thin copper foil with carrier foil, its manufacturing method, and the printed wiring board which employ | adopted this.

The printed wiring board can be manufactured, for example, as follows. First, ultra-thin copper foil is arrange | positioned on the surface of the insulating substrate which consists of resin etc., and it heats and pressurizes and manufactures a laminated board. Subsequently, through-hole plating and through-hole plating are performed on the laminated plate in order to provide plated through holes, and copper foil on the surface of the laminated plate is etched to form a wiring pattern having the necessary line width and line pitch. Then, finally, solder-resist formation or other processing is performed.

About the said copper foil, the surface on the side thermocompression-bonded to a board | substrate is made into a roughening surface, the anchoring effect with respect to a board | substrate is exhibited in this roughening surface, the joint strength of the said board | substrate and copper foil is raised, and reliability as a printed wiring board is improved. Secure.

In recent years, a rough surface of copper foil is previously bonded to an adhesive resin such as an epoxy resin, and the adhesive resin is used as an insulating resin layer in a semi-cured state (B stage), whereby a copper foil with a resin is used as a copper foil for surface circuit formation. While using, the said insulating resin layer is thermocompression-bonded to an insulated substrate, and manufacturing a printed wiring board, especially a build-up wiring board, is performed.

In such a build-up wiring board, various electronic components are required to be highly integrated, and correspondingly, the wiring pattern is also required to be densified, so that a wiring pattern consisting of wiring having a fine line width or line pitch, that is, a printed wiring board having a fine pattern is required. . For example, a high-density printed wiring board having a line width or line pitch of about 20 mu m is required.

Has a via hole (via hole) formed on the build-up wiring board, it has become a laser via process by CO ₂ gas laser liquor from the reason such as a high productivity. However, when a CO ₂ gas laser is used for a conventional ultra-thin copper foil, the wavelength of the CO ₂ gas laser is about 10,600 nm in the infrared region, so that the surface of the copper foil reflects most of the light of this region and does not perform direct via hole processing. Since the copper foil of the via hole formation part was not able to be etched and removed in advance, the conformal mask method which performs via hole processing to the base material was used. However, the conformal mask method, without coating an etching resist on the area you want to install compared hole of the ultra-thin copper foil, to the other part, coating the etched resistor, after etching the pre-pole bakdongbak substrate with a CO ₂ gas laser (Resin Take a complicated way of making via holes in the part). Therefore, via-hole processing can be simplified if an ultra-thin copper foil and a resin part can be simultaneously processed using a CO ₂ gas laser.

On the other hand, in order to absorb light of the CO ₂ wavelength well, a method of laser processing after forming a separate oxide layer on copper was also used. However, when the ultra-thin thickness is thin, about 70% of copper is lost when the actual oxide layer is formed, and it is difficult to secure a copper seed layer having a uniform thickness required for chemical copper plating.

Therefore, there is a need for a carrier foil ultrathin copper foil that can be via hole processed simultaneously in ultrathin copper foil and resin while having low reflectance for a CO ₂ gas laser without forming an additional oxide layer.

One aspect is to provide an ultrathin copper foil with a carrier foil having a low reflectance with respect to a carbon dioxide laser.

Another aspect is to provide a printed wiring board employing the ultra-thin copper foil with a carrier foil.

Another aspect is to provide a method for producing the ultrathin copper foil with a carrier foil.

On one side

As an ultrathin copper foil with a carrier foil in which a carrier foil, a peeling layer, and an ultrathin copper foil are laminated sequentially,

The ultra-thin copper foil with a carrier foil which has a low reflectance with respect to the light of the wavelength which the said peeling layer oscillates from a carbon dioxide gas laser is provided.

According to another aspect,

The printed wiring board which laminates the ultra-thin copper foil with carrier foil which concerns on the above to a resin substrate is provided.

According to another aspect,

An ultra-thin copper foil with a carrier foil comprising the step of forming a plated release layer from a plating bath having a pH of 9.5 or higher to which a first metal, a second metal, a third metal, a metal salt of citric acid, and ammonia water have been added to the smooth surface of the carrier copper foil. A method for producing is provided.

According to one aspect, the laser workability of the ultra-thin copper foil with a carrier foil can be improved by including a peeling layer having a low reflectance with respect to a carbon dioxide laser.

1 is a schematic cross-sectional view of an ultra-thin copper foil with a carrier foil according to an exemplary embodiment of the present invention.
FIG. 2 is an image of a surface layer via hole formed with a carbon dioxide laser for the specimen of Example 2. FIG.

Hereinafter, the ultra-thin copper foil with a carrier foil, a manufacturing method thereof, and a printed circuit board employing the same according to at least one exemplary embodiment will be described in more detail.

The ultra-thin copper foil with a carrier foil according to one embodiment of the present invention is an ultra-thin copper foil with a carrier foil formed by sequentially stacking a carrier foil, a peeling layer, and an ultra-thin copper foil, with respect to light having a wavelength oscillating from the carbon dioxide gas laser. Has a low reflectance. The schematic diagram of the ultra-thin copper foil with a carrier foil is shown in FIG. The low reflectance of the release layer means that the release layer has a lower reflectance for light of a wavelength oscillated from carbon dioxide than pure copper. Since the exfoliation layer includes a component that exhibits a low reflectance with respect to the light emitted from the carbon dioxide gas laser, the carbon dioxide gas laser absorbs the light emitted without reflection and forms a via hole having a uniform size. It can also satisfy the role of inhibiting oxidation of the copper foil surface. Therefore, the release layer may simultaneously perform two roles of the laser absorption layer and the release layer, and the structure of the ultra-thin copper foil with carrier foil may be simplified.

1st metal (A) which the said peeling layer has peelability in the said carrier foil ultra-thin copper foil; And a second metal (B) and a third metal (C) for facilitating the plating of the first metal, wherein the content (a) of the first metal constituting the release layer is 30 to 89 wt%, It is preferable that content (b) of 2nd metal is 10-60 weight%, and content (c) of 3rd metal is more than 20-40 weight%. Preferably, the release layer consists of an alloy layer of the first metal, the second metal and the third metal.

When the content (a) of the first metal and the content (b) of the second metal are outside the content ranges, the peelability of the ultrathin copper foil may decrease, and the content (c) of the third metal is the content. Outside the range, peelability and laser workability may be degraded.

For example, if the content of the third metal is 20% by weight or less, the peelability is good, but the deviation of the via hole is severe during carbon dioxide gas laser processing, and the quality is degraded. In addition, uniform plating is difficult when the content of the third metal is more than 40% by weight.

In addition, the second metal and the third metal may be adsorbed on the surface of the carrier foil to serve as a catalyst in the plating of the first metal. The above-mentioned carrier ultrathin copper foil can suppress generation | occurrence | production of a float in high temperature environment, and can easily peel an ultrathin copper foil from carrier foil. If only one type of metal is used as the metal serving as a catalyst for the plating of the first metal, the uniformity of the release layer is lowered.

The contents a, b, and c of the metals are set such that the amount (coating amount) of the first metal (A) per unit area of 1 dm ² of the release layer is less than the amount of the first metal (A), the second metal (Coating amount) of the metal (C) divided by the sum of the amount of the coating amount of the metal (C).

According to another embodiment of the present invention, the first metal is Mo or W, and the second metal and the third metal are preferably two different metals selected from the group consisting of Fe, Co, and Ni. More preferably, the first metal is Mo, the second metal is Ni and the third metal is Fe.

When a peeling layer is formed only by the said 1st metal and a 2nd metal, the phenomenon in which peelability of a peeling layer is nonuniform arises. And the peeling layer shows the tendency which peels with an ultra-thin copper foil at the time of peeling. In addition, the laser reflectance increases, which lowers the laser workability. For example, the diameter of the via hole formed by the carbon dioxide laser becomes small and the deviation also increases.

On the contrary, in the present invention, when the peeling layer is formed only of the first metal and the second metal (for example, Mo-Ni alloy layer), the peeling property is unstable, In order to increase the plating amount of the Mo metal, Fe ions serving as a catalyst for plating the Mo metal are additionally added as a third metal. The addition of Fe ions allows for uniform plating of the release layer and increased absorption of the carbon dioxide gas laser.

According to another embodiment of the present invention, the sum of the adhesion amounts of the release layer formed on the surface of the carrier foil is preferably 0.05 to 10 mg / dm ² . If the adhesion amount is less than 0.05 mg / dm ² , it is not preferable because it does not exhibit sufficient function as a release layer. If the adhesion amount is more than 10 mg / dm ² , it is not an oxidizable substance, which is a peelable substance, but a metallic substance, and thus peelability is lost. . It is preferable that the surface roughness of the said peeling layer is 1.5 times or less of the roughness of the carrier foil surface, and the surface area of the said peeling layer is also 1.5 times or less of the surface area of the said carrier foil. The greater the surface roughness and the surface area, the greater the peeling strength and the greater the variation.

The ultrathin copper foil is formed by electrolytic plating on a release layer using an electrolytic bath such as copper sulfate, pyrophosphoric acid copper, cyanated copper, or sulfamic acid copper. The plating bath is preferably a copper plating bath having a pH between 1 and 12.

The formation of ultrathin copper foil is performed when the surface of the peeling layer is formed of a metal which is easily dissolved in a plating solution such as Cu. The immersion time in the plating solution, the current value, the plating solution removal in the plating finishing process, water washing, and the plating solution pH immediately after the metal plating are peeled off. Since the state of the layer surface is determined, the type of bath needs to be selected in consideration of the relationship between the surface of the release layer and the metal formed thereon.

Further, it is very difficult to form an ultra-thin copper foil on the release layer due to the peelability of the release layer, which may result in the presence of a large number of pinholes in the ultra-thin copper foil. In such plating conditions, it is preferable to perform strike copper plating first, followed by ordinary electrolytic plating. When strike plating is performed, it is possible to perform uniform plating on the release layer, which can greatly reduce the number of pinholes generated in the ultrathin copper foil.

The thickness of the copper plating to be adhered by the strike plating is preferably 0.001 to 1 µm, and the conditions vary depending on the type of bath, but the current density is preferably 0.1 to 20 A / dm ² and the plating time is 0.1 to 300 seconds. It is difficult to make the plating uniform on the exfoliation layer at a current density of 0.1 A / dm ² or less, and at a current density of more than 20 A / dm ² , the metal oxide is caused by plating above the limit current density in the strike plating which lowers the metal concentration of the plating solution. It becomes difficult to obtain a uniform copper foil layer due to plating (burning phenomenon occurs). If the plating time is less than 0.1 second, it is difficult to obtain a sufficient plating layer. If the plating time is 300 seconds or more, the productivity decreases.

A copper plating layer having a thickness of 0.001 µm or more, which is a thickness that does not lower the peelability of the release layer, is formed on the release layer by strike plating, and then copper electroplating is performed to a predetermined thickness to form an ultrathin copper foil. As for the thickness of ultra-thin copper foil, 1-5 micrometers is preferable. In the case of ultra-thin copper foil, copper foil having rough and non-coarse screens is possible depending on the application. In the case of rough screen, it is formed through nodulation treatment. do.

Moreover, surface treatment can be given to one surface (surface joined with resin) of the ultra-thin copper foil which concerns on one Embodiment of this invention in order to make adhesiveness of metal foil and insulating resin into a practical level or more. Examples of the surface treatment on the copper foil include any one or a combination of heat and chemical resistance treatment, chromate treatment, silane coupling treatment, and the like, and what kind of surface treatment is performed depending on the resin used as the insulating resin. It is desirable to examine appropriately.

The heat resistant and chemical resistance treatment is carried out by forming a thin film on a metal foil by sputtering, electroplating or electroless plating, for example, any one of metals such as nickel, tin, zinc, chromium, molybdenum and cobalt or their alloys can do. In terms of cost, electroplating is preferable. In order to facilitate precipitation of metal ions, a complexing agent such as citrate, tartarate, and sulfamic acid may be added in a required amount.

As the chromate treatment, an aqueous solution containing hexavalent chromium ions is preferably used. The chromate treatment may be a simple immersion treatment, but is preferably performed by a negative treatment. At a bath temperature of from 15 to 60 DEG C, at a current density of from 0.1 to 5 A / dm < 2 > and at an electrolysis time of from 0.1 to 100 seconds. Chromic acid or potassium dichromate may be used instead of sodium dichromate. The chromate treatment is preferably carried out in the rust-preventive treatment, whereby the moisture resistance and the heat resistance can be further improved.

Examples of the silane coupling agent used in the silane coupling treatment include epoxy functional silanes such as 3-glycidoxypropyltrimethoxysilane and 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, Aminopropyltrimethoxysilane such as 3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane and N-2- (aminoethyl) , Vinyltrimethoxysilane, vinylphenyltrimethoxysilane, vinyltris (2-methoxyethoxy) silane and the like, acrylic functional silanes such as 3-acryloxypropyltrimethoxysilane, 3- Methacrylic functional silanes such as methacryloxypropyltrimethoxysilane, and mercapto functional silanes such as 3-mercaptopropyltrimethoxysilane. These may be used alone, or a plurality of them may be mixed and used. Such a coupling agent is dissolved in a solvent such as water at a concentration of 0.1 to 15 g / L, applied to a metal foil at a temperature of room temperature to 50 ° C, or electrodeposited to adsorb. These silane coupling agents form a film by condensation-bonding with the hydroxyl group of the antirust process metal on the metal foil surface. After the silane coupling treatment, a stable bond is formed by heating, ultraviolet irradiation or the like. The heating is dried for 2 to 60 seconds at a temperature of 100 to 200 ° C. Ultraviolet irradiation is performed in the range of 200-400 nm and 200-2500 mJ / cm <2>. Moreover, it is preferable to perform a silane coupling process to outermost layer of copper foil, and can improve the adhesiveness of a moisture-proof and an insulated resin composition layer and metal foil further by this.

According to another embodiment of the present invention, a printed wiring board is formed by stacking ultra-thin copper foil of the ultra-thin copper foil with carrier foil on a resin substrate. The printed wiring board is suitable for a printed circuit wiring board for a high density fine pattern, a multilayer printed wiring board, a wiring board for chip on film, and a flexible substrate.

The manufacturing method of the ultra-thin copper foil with carrier foil which concerns on other embodiment of this invention is pH 9.5 or more which the 1st metal, the 2nd metal, the 3rd metal, the metal salt of citric acid, and the ammonia water or ammonium salt were added to the smooth surface of a carrier copper foil. Forming a plated release layer from the plating bath.

In the manufacturing method, it is preferable that the first metal is Mo or W, and the second metal and the third metal are two different metals selected from the group consisting of Fe, Co and Ni, more preferably the first metal. The metal is Mo, the second metal is Ni and the third metal is Fe.

In the production method, the concentration of the first metal included in the plating bath is 1 to 100 g / L, the concentration of the second metal is 1 to 40 g / L, and the concentration of the third metal is preferably 1 to 50 g / L. The range is suitable for achieving the object of the present invention.

When the metal salt of citric acid is added to the plating bath, it becomes a citrate ion. The metal salt of citric acid is preferably potassium citrate, sodium citrate, iron citrate, calcium citrate, tin citrate, iron ammonium citrate or a mixture thereof. The citrate ions serve to help the first metal to be plated with the metal oxide and to lower the voltage of the plating bath. For example, in a plating bath to which Mo, Ni and Fe are added, when a citrate ion reacts with Ni to form a complex of Ni and citrate, MoO ₄ ^2- easily forms a plating layer in the form of MoO ₂ . The concentration of the metal citrate salt contained in the plating bath is preferably 5 to 200 g / L, more preferably 15 to 150 g / L.

The pH of the plating bath is preferably at least 9.5. If the pH is less than 9.5, it is difficult to form in the peeling layer. For example, the pH of the plating bath may be 9.6 or more. For example, the pH of the plating bath may be 10.0 or more. As the compound added to adjust the pH of the plating bath, ammonia water or ammonium salt is preferable. The content of ammonia water or ammonium salt is preferably 0.001 to 0.5N.

According to another embodiment of the present invention, the concentration of the first metal in the plating bath is 1-100 g / L, the concentration of the second metal is 1-40 g / L, and the concentration of the third metal is 1- in the manufacturing method. It is preferable that the concentration of 50 g / L, the metal salt of citric acid is 5 to 200 g / L, and the content of aqueous ammonia or ammonium salt is 0.001 to 1N.

The manufacturing method of the ultra-thin copper foil with carrier foil which concerns on one Embodiment of this invention is as follows. First, an electrolytic copper foil having a predetermined surface roughness and thickness is pickled by strong acid such as sulfuric acid and washed with pure water to prepare a carrier copper foil. The peeling layer plated from the plating bath of pH 9.5 or more which immersed the said carrier copper foil in the plating bath, and added the 1st metal, the 2nd metal, the 3rd metal, the metal salt of citric acid, and the ammonia water or ammonium salt to the smooth surface of the said carrier copper foil. To form. Subsequently, a predetermined copper foil layer is formed on the surface of the release layer through strike plating, and then ultra-thin copper foil is formed by electrolytic plating. Specific implementation conditions for the carrier copper foil preparation, strike plating layer formation and ultra-thin copper foil formation can be appropriately adjusted as necessary.

Hereinafter, the present invention will be described in further detail with reference to preferred examples, but the present invention is not limited thereto.

(Production of ultrathin copper foil with carrier foil)

Example 1

1. Preparation of carrier foil

An electrolytic copper foil having a surface roughness (Rz) of 1.5 μm or less and a thickness of 18 μm on a glossy surface was immersed in 100 g / L sulfuric acid for 5 seconds, and then washed with pure water after pickling treatment.

2. Formation of release layer

A peeling layer of Mo-Ni-Fe plating was formed in a plating bath under the following conditions.

Mo concentration: 20g / L, Ni concentration: 6.5g / L, Fe concentration: 6.5g / L

Sodium Citrate: 150g / L

pH 10.31 (30 mL / L of ammonia water added)

Plating bath temperature: 25 ℃

Current Density: 10A / dm ²

Current duration: 7 seconds

The adhesion amount of the formed release layer was 1.07 mg / dm ² , and the composition of the release layer was 45 wt% Mo, 24 wt% Ni, and 31 wt% Fe.

3. Strike Plating Layer Formation

A pyrophosphoric acid copper strike plating bath or a copper cyanide strike plating bath having the following composition was selected to form a strike plating layer under the following conditions.

Plating bath temperature: 25 ℃

Current density: 5 A / dm ²

Current duration: 7 seconds

Pyrophosphoric acid copper strike plating bath composition

K ₄ P ₂ O ₇ : 125 g / L, Cu ₂ P ₂ O ₇ 4H ₂ O: 25 g / L

KNO ₃ : 2 g / L, pH 8

Cyanide copper plated bath composition

CuCN 5H ₂ O: 30 g / L, KCN: 60 g / L, pH 12

4. Formation of ultrathin copper foil

Ultrathin copper foil was formed in the plating bath of the following conditions.

H ₂ SO ₄ 5H ₂ O: 350 g / L, H ₂ SO ₄ : 150 g / L

Plating bath temperature: 60 ℃

Current Density: 10A / dm ²

Current duration: 7 seconds

Example 2

The same process as in Example 1 was carried out except that the plating bath composition for the release layer formation was changed as follows.

2. Formation of release layer

Mo concentration: 20g / L, Ni concentration: 6.5g / L, Fe concentration: 5g / L

Sodium Citrate: 150g / L

pH 10.28 (add 30 mL / L of ammonia water)

Plating bath temperature: 25 ℃

Current Density: 10A / dm ²

Current duration: 7 seconds

The adhesion amount of the formed release layer was 1.04 mg / dm ² , and the composition of the release layer was 40 wt% Mo, 27 wt% Ni, and 23 wt% Fe.

Comparative Example 1

The same process as in Example 1 was carried out except that the plating bath composition for the release layer formation was changed as follows.

2. Formation of release layer

Mo concentration: 20g / L, Ni concentration: 6.5g / L, Fe concentration: 3g / L

Sodium Citrate: 150g / L

pH 10.28 (add 30 mL / L of ammonia water)

Plating bath temperature: 25 ℃

Current Density: 10A / dm ²

Current duration: 7 seconds

The adhesion amount of the formed release layer was 1.03 mg / dm ² , and the composition of the release layer was 63 wt% Mo, 24 wt% Ni, and 13 wt% Fe.

Comparative Example 2

The same process as in Example 1 was carried out except that the plating bath composition for the release layer formation was changed as follows.

2. Formation of release layer

Mo concentration: 20g / L, Ni concentration: 6.5g / L, Fe concentration: 1g / L

Sodium Citrate: 150g / L

pH 10.28 (add 30 mL / L of ammonia water)

Plating bath temperature: 25 ℃

Current Density: 10A / dm ²

Current duration: 7 seconds

The adhesion amount of the formed release layer was 1.07 mg / dm ² , and the composition of the release layer was 59 wt% Mo, 36 wt% Ni, and 5 wt% Fe.

Comparative Example 3

The same process as in Example 1 was carried out except that the plating bath composition for the release layer formation was changed as follows.

2. Formation of release layer

Mo concentration: 20g / L, Ni concentration: 6.5g / L

Sodium Citrate: 150g / L

pH 10.28 (add 30 mL / L of ammonia water)

Plating bath temperature: 25 ℃

Current Density: 10A / dm ²

Current duration: 7 seconds

The adhesion amount of the formed release layer was 0.867 mg / dm ² , and the composition of the release layer was 66% by weight of Mo and 34% by weight of Ni.

Evaluation Example 1: Evaluation of Laser Processing Characteristics

The ultra-thin copper foil with a carrier foil prepared in Examples 1 to 2 and Comparative Examples 1 to 3 was disposed on the bismaleimide-triazine resin (BT-resin, Mitsubish Gas Chemical Inc.) so as to face the ultra-thin copper foil, and the whole was 2 The specimens were prepared by inserting them into two smooth-rolled stainless steel sheets and thermocompressing them for 120 minutes at a temperature of 220 ° C. and an eye pressure of 45 kgf / cm ² .

The size of the formed via holes was evaluated after irradiating a laser of 32 W with a carbon dioxide (CO ₂ ) gas laser via hole processor. The via hole formed with respect to the ultra-thin copper foil with a carrier foil manufactured in Example 2 is shown by FIG.

Diameter of via hole surface layer [占 퐉] Diameter deviation
[Mu m] Example 1 79-82 3 Example 2 77 ~ 83.2 6.2 Comparative Example 1 72-81 9 Comparative Example 2 65-77 12 Comparative Example 3 65-79 14

At present, the commercially required via hole diameter of the surface layer is 70 to 90 mu m.

As shown in Table 1, the specimens of Examples 1 and 2 are in the range of 70 to 90㎛ surface layer diameter and the diameter was small. That is, the specimens of Examples 1 to 2 had low reflectances of lasers, so that via holes having a uniform diameter were formed.

In contrast, the specimens of Comparative Examples 1 to 3 had a surface layer diameter of 70 μm or less, or a large variation in via hole diameter. That is, the specimens of Comparative Examples 1 to 3 do not satisfy the required via hole diameter due to the high reflectance of the laser, or do not form via holes having a uniform diameter.

Carrier Copper Foil 1 Peeling Layer 2
Ultrathin copper foil 3

Claims (13)

As an ultrathin copper foil with a carrier foil in which a carrier foil, a peeling layer, and an ultrathin copper foil are laminated sequentially,
The exfoliation layer has a low reflectance for light of a wavelength oscillating from a carbon dioxide gas laser,
The content (a) of the first metal constituting the release layer is 30 to 63% by weight, the content (b) of the second metal is 10 to 36% by weight and the content (c) of the third metal is more than 20 to 40% by weight. Ultrathin copper foil with a carrier foil, which is%. The method according to claim 1, wherein the release layer comprises a first metal (A) having releasability; And a second metal (B) and a third metal (C) for facilitating plating of the first metal. delete 3. The ultrathin with carrier foil according to claim 2, wherein the first metal is Mo or W, and the second metal and the third metal are two different metals selected from the group consisting of Fe, Co, and Ni. Copper foil. The ultra-thin copper foil with a carrier foil according to claim 2, wherein the first metal is Mo, the second metal is Ni, and the third metal is Fe. The ultra-thin copper foil with a carrier foil according to claim 1, wherein the total amount of the adhesion of the release layer is 0.05 to 10 mg / dm ² . The printed wiring board formed by laminating | stacking the ultra-thin copper foil of the ultra-thin copper foil with carrier foil as described in any one of Claims 1-2, and 4-6. As an ultra-thin copper foil manufacturing method with a carrier foil of claim 1,
Forming a release layer plated on a smooth surface of the carrier copper foil from a plating bath having a pH of 9.5 or higher to which a first metal, a second metal, a third metal, a metal salt of citric acid, and ammonia water or ammonium salt are added,
The concentration of the first metal contained in the plating bath is 1-100 g / L, the concentration of the second metal is 1-40 g / L, the concentration of the third metal is 1-50 g / L, and the concentration of the metal salt of citric acid is 5-. 200 g / L, and content of ammonia water or ammonium salt is 0.001-1N, The manufacturing method of the ultra-thin copper foil with a carrier foil characterized by the above-mentioned. 9. The ultra-thin carrier foil as claimed in claim 8, wherein the first metal is Mo or W, and the second metal and the third metal are two different metals selected from the group consisting of Fe, Co and Ni. The manufacturing method of copper foil. The said 1st metal is Mo, the said 2nd metal is Ni, and the said 3rd metal is Fe, The manufacturing method of the ultra-thin copper foil with a carrier foil of Claim 8 characterized by the above-mentioned. The ultra-thin copper foil with a carrier foil according to claim 8, wherein the metal salt of citric acid is one paper compound selected from the group consisting of potassium citrate, sodium citrate, iron citrate, calcium citrate, trisodium citrate and ammonium ferric citrate. Method of preparation. The pH of the said plating bath is 9.5 or more, The manufacturing method of the ultra-thin copper foil with carrier foil of Claim 8 characterized by the above-mentioned. delete

Images