WO2013118416A1

WO2013118416A1 - Copper foil with carrier, manufacturing method for copper foil with carrier, printed wiring board, printed circuit board and copper clad laminate

Info

Publication number: WO2013118416A1
Application number: PCT/JP2012/083722
Authority: WO
Inventors: 美里中願寺; 友太永浦
Original assignee: Jx日鉱日石金属株式会社
Priority date: 2012-02-06
Filing date: 2012-12-26
Publication date: 2013-08-15
Also published as: JPWO2013118416A1; TW201341600A; JP5903446B2; TWI465613B

Abstract

A copper foil with a carrier provided with a copper foil carrier, an intermediate layer laminated on the copper foil carrier, and an ultrathin copper layer laminated on the intermediate layer. The intermediate layer is configured by laminating nickel and chromate in said order on the copper foil carrier. The amount of adhering nickel is 100-40000 µg/dm² and the amount of adhering chromium is 5-100 µg/dm². If, when peeling between the intermediate layer and the ultrathin copper layer, the chromium atom concentration in the depth direction (x: in nm units) obtained from analysis in the depth direction from the surface using XPS is f(x), the nickel atom concentration is g(x) and the concentration of other atoms is l(x), the copper foil with a carrier satisfies ∫f(x)dx/(∫f(x)dx+∫g(x)dx+∫l(x)dx) being 1-30% and ∫g(x)dx/(∫f(x)dx+∫g(x)dx+∫l(x)dx) being 1-50% in the interval [0, 1.0] of the analysis in the depth direction from the surface of the intermediate layer and ∫g(x)dx/(∫f(x)dx+∫g(x)dx+∫l(x)dx) being 40% or more in the interval [1.0, 4.0].

Description

Copper foil with carrier, method for producing copper foil with carrier, printed wiring board, printed circuit board, and copper-clad laminate

The present invention relates to a copper foil with a carrier, a method for producing a copper foil with a carrier, a printed wiring board, a printed circuit board, and a copper clad laminate. More specifically, the present invention relates to a copper foil with a carrier used as a material for a printed wiring board for fine patterns, a method for producing the copper foil with a carrier, a printed wiring board, a printed circuit board, and a copper clad laminate.

Printed wiring boards have made great progress over the last half century, and today they are used in almost all electronic devices. In recent years, with the increasing demand for miniaturization and high performance of electronic devices, higher density mounting of components and higher frequency of signals have progressed, and conductor patterns have become finer (fine pitch) and printed circuit boards. There is a demand for high frequency response, and in particular, when an IC chip is mounted on a printed wiring board, a fine pitch of L / S = 20/20 or less is required.

First, a printed wiring board is manufactured as a copper clad laminate in which an insulating substrate mainly composed of a copper foil and a glass epoxy substrate, a BT resin, a polyimide film or the like is bonded. Bonding is performed by laminating an insulating substrate and a copper foil and applying heat and pressure (laminating method), or by applying a varnish that is a precursor of an insulating substrate material to a surface having a coating layer of copper foil, A heating / curing method (casting method) is used.

With the fine pitch, the thickness of the copper foil used for the copper clad laminate is 9 μm, and further the thickness is becoming 5 μm or less. However, when the foil thickness is 9 μm or less, the handleability when forming a copper clad laminate by the above-described lamination method or casting method is extremely deteriorated. Therefore, a copper foil with a carrier has appeared, in which a thick metal foil is used as a carrier, and an ultrathin copper layer is formed on the metal foil via a release layer. A general method of using a copper foil with a carrier is to peel the carrier through a release layer after the surface of the ultrathin copper layer is bonded to an insulating substrate and thermocompression bonded.

As a technique related to a copper foil with a carrier, for example, in Patent Document 1, a diffusion prevention layer, a release layer, and an electrolytic copper plating are formed in this order on the surface of a carrier, and a Cr or Cr hydrated oxide layer is formed as a release layer. A method for maintaining good peelability after hot pressing by using a simple substance or an alloy of Ni, Co, Fe, Cr, Mo, Ta, Cu, Al, P as a diffusion preventing layer is disclosed.

It is also known that the release layer is formed of Cr, Ni, Co, Fe, Mo, Ti, W, P, alloys thereof or hydrates thereof. Furthermore,

Patent Documents

2 and 3 describe that it is effective to provide Ni, Fe or an alloy layer thereof as a base of the release layer in order to stabilize the peelability in a high temperature use environment such as a hot press. Has been.

JP 2006-022406 A JP 2010-006071 A JP 2007-007937 A

In copper foil with a carrier, it is necessary to avoid the peeling of the ultrathin copper layer from the carrier before the lamination process on the insulating substrate, while the ultrathin copper layer from the carrier is removed after the lamination process to the insulating substrate. Must be peelable. In addition, in the copper foil with a carrier, the presence of pinholes on the surface of the ultrathin copper layer is not preferable because it leads to poor performance of the printed wiring board.

These points have not been sufficiently studied in the prior art, and there is still room for improvement. Therefore, an object of the present invention is to provide a copper foil with a carrier that can be peeled off after a lamination process on an insulating substrate, while the ultrathin copper layer does not peel off from the carrier before the lamination process on the insulating substrate. . Another object of the present invention is to provide a carrier-attached copper foil in which the generation of pinholes on the ultrathin copper layer side surface is suppressed.

In order to achieve the above object, the present inventor conducted extensive research and used copper foil as a carrier, formed an intermediate layer between the ultrathin copper layer and the carrier, and formed this intermediate layer on the copper foil carrier. Consist of nickel and chromate in order, control the amount of nickel and chromium deposited, and control the chromium and nickel atom concentration on the intermediate layer surface when peeled between the intermediate layer and ultrathin copper layer Has been found to be extremely effective. It is also extremely effective to control the chromium and nickel atom concentration on the surface of the intermediate layer when the insulating substrate is thermocompression bonded to the ultrathin copper layer and the carrier is peeled off from the ultrathin copper layer. I found.

The present invention has been completed on the basis of the above knowledge, and in one aspect, includes a copper foil carrier, an intermediate layer laminated on the copper foil carrier, and an ultrathin copper layer laminated on the intermediate layer. A copper foil with a carrier,
The intermediate layer is configured by laminating nickel and chromate in this order on the copper foil carrier,
Adhesion amount 100 ~ 40000μg / dm ² of nickel, the adhesion amount of chromium is 5 ~ 100μg / dm ^2,
When peeling between the intermediate layer and ultrathin copper layer, the atomic concentration (%) of chromium in the depth direction (x: unit nm) obtained from the depth direction analysis from the surface by XPS is defined as f (x). The atomic concentration (%) of nickel is g (x), the atomic concentration (%) of copper is h (x), the total atomic concentration (%) of oxygen is i (x), and the atomic concentration of carbon (% ) Is j (x) and other atomic concentration (%) is k (x),
In the section [0, 1.0] of the depth direction analysis from the intermediate layer surface, ∫f (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) is 1-30%, ∫g (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) is 1 to 50%, and [1.0, 4.0], ∫g (x) dx / With carrier satisfying (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) Copper foil.

In one embodiment of the carrier-attached copper foil according to the present invention, when peeling between the intermediate layer / ultra-thin copper layer, a section [0, 1.0] of depth direction analysis from the intermediate layer surface by XPS ∫f (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx ) Satisfies 2 to 25%.

In another embodiment of the copper foil with a carrier according to the present invention, when peeling between the intermediate layer / ultra-thin copper layer, the section [1.0, 4.0], ∫h (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) satisfies 1 to 30.

In yet another embodiment of the copper foil with a carrier according to the present invention, the binding energy of the 2P3 / 2 orbit of chromium detected by XPS of the intermediate layer is in the range of 576 to 580 eV.

In yet another embodiment of the copper foil with a carrier according to the present invention, the ultrathin copper layer is thermocompression-bonded under the conditions of an insulating substrate in the atmosphere, pressure: 20 kgf / cm ² , 220 ° C. × 2 hours, When peeling between the intermediate layer and ultrathin copper layer, the atomic concentration (%) of chromium in the depth direction (x: unit nm) obtained from the depth direction analysis from the surface by XPS is defined as f (x). The atomic concentration (%) of nickel is g (x), the atomic concentration (%) of copper is h (x), the total atomic concentration (%) of oxygen is i (x), and the atomic concentration of carbon (% ) Is j (x) and other atomic concentration (%) is k (x),
In the section [0, 1.0] of the depth direction analysis from the intermediate layer surface, ∫f (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) is 0.5-30%, ∫g (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) is 1 to 50% and [1.0, 4.0], ∫g (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) satisfies 40% or more .

In yet another embodiment of the copper foil with a carrier according to the present invention, the ultrathin copper layer is thermocompression-bonded under the conditions of an insulating substrate in the atmosphere, pressure: 20 kgf / cm ² , 220 ° C. × 2 hours, When delamination is performed between the intermediate layer and the ultrathin copper layer, ∫f (x) dx / (∫f (x) in the section [0, 1.0] in the depth direction analysis from the intermediate layer surface by XPS dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) satisfies 1 to 25%.

In yet another embodiment of the copper foil with a carrier according to the present invention, the ultrathin copper layer is thermocompression-bonded under the conditions of an insulating substrate in the atmosphere, pressure: 20 kgf / cm ² , 220 ° C. × 2 hours, When peeling between the intermediate layer / ultra-thin copper layer, in the section [1.0, 4.0] of the depth direction analysis from the intermediate layer surface by XPS, ∫h (x) dx / (∫f ( x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) satisfies 2 to 40%.

In yet another embodiment of the copper foil with a carrier according to the present invention, the copper foil carrier is formed of an electrolytic copper foil or a rolled copper foil.

In yet another embodiment of the copper foil with a carrier according to the present invention, the surface of the ultrathin copper layer has a roughening treatment layer.

In still another embodiment of the copper foil with a carrier according to the present invention, the roughening treatment layer is any one selected from the group consisting of copper, nickel, cobalt and zinc, or any one or more. It is a layer made of an alloy containing.

In still another embodiment of the copper foil with a carrier according to the present invention, one or more types selected from the group consisting of a rust prevention layer, a chromate treatment layer and a silane coupling treatment layer on the surface of the roughening treatment layer. It has a layer of.

In still another embodiment of the copper foil with a carrier according to the present invention, one or more selected from the group consisting of a rust prevention layer, a chromate treatment layer and a silane coupling treatment layer on the surface of the ultrathin copper layer. It has a layer of.

In another aspect of the present invention, a nickel plating is formed on a copper foil carrier, and then an intermediate layer is formed by forming a chromate layer by electrolytic chromate, and an extremely thin layer is formed by electrolytic plating on the intermediate layer. And a step of forming a copper layer.

In another aspect of the present invention, a nickel plating is formed on a copper foil carrier and then an intermediate layer is formed by forming a chromate layer by electrolytic chromate, and an electrode is formed on the intermediate layer by electrolytic plating. It is a manufacturing method of copper foil with a carrier including the process of forming a thin copper layer, and the process of forming a roughening process layer on the said ultra-thin copper layer.

In yet another aspect, the present invention is a printed wiring board manufactured using the carrier-attached copper foil of the present invention.

In still another aspect, the present invention is a printed circuit board manufactured using the carrier-attached copper foil of the present invention.

In yet another aspect, the present invention is a copper clad laminate manufactured using the carrier-attached copper foil of the present invention.

The copper foil with a carrier according to the present invention has high adhesion between the carrier and the ultrathin copper layer before the lamination process to the insulating substrate, while the carrier and the ultrathin copper layer after the lamination process to the insulation substrate. Adhesiveness is lowered, it can be easily peeled off at the carrier / ultra-thin copper layer interface, and the occurrence of pinholes on the surface of the ultra-thin copper layer can be well suppressed.

It is a XPS depth profile of the depth direction of the intermediate | middle layer surface before board | substrate bonding of Example 2. FIG. It is an XPS depth profile of the depth direction of the intermediate | middle layer surface before the board | substrate bonding of the comparative example 3. FIG. It is the XPS depth profile of the depth direction of the ultra-thin copper layer surface before board | substrate bonding of Example 2. FIG.

<1. Career>
A copper foil is used as a carrier that can be used in the present invention. The carrier is typically provided in the form of rolled copper foil or electrolytic copper foil. In general, the electrolytic copper foil is produced by electrolytic deposition of copper from a copper sulfate plating bath onto a drum of titanium or stainless steel, and the rolled copper foil is produced by repeating plastic working and heat treatment with a rolling roll. In addition to high-purity copper such as tough pitch copper and oxygen-free copper, the copper foil material is, for example, Sn-containing copper, Ag-containing copper, copper alloy added with Cr, Zr, Mg, etc., and Corson-based added with Ni and Si Copper alloys such as copper alloys can also be used. In addition, when the term “copper foil” is used alone in this specification, a copper alloy foil is also included.

The thickness of the carrier that can be used in the present invention is not particularly limited, but may be appropriately adjusted to a thickness suitable for serving as a carrier, for example, 12 μm or more. However, if it is too thick, the production cost becomes high, so generally it is preferably 35 μm or less. Accordingly, the thickness of the carrier is typically 12-70 μm, more typically 18-35 μm.

<2. Intermediate layer>
An intermediate layer is provided on the copper foil carrier. The intermediate layer is formed by laminating nickel and chromate in this order on a copper foil carrier. Since the adhesive strength between nickel and copper is higher than the adhesive strength between chromium and copper, when the ultrathin copper layer is peeled off, it peels at the interface between the ultrathin copper layer and chromate. Further, the nickel of the intermediate layer is expected to have a barrier effect that prevents the copper component from diffusing from the carrier into the ultrathin copper layer.
Also, chromate is formed on the intermediate layer instead of chrome plating. Since chromium plating forms a dense chromium oxide layer on the surface, when an ultrathin copper foil is formed by electroplating, the electrical resistance increases and pinholes are likely to occur. Since the chromium oxide layer that is not as dense as chromium plating is formed on the surface on which the chromate is formed, it is difficult to become resistance when forming an ultrathin copper foil by electroplating, and pinholes can be reduced.
When using electrolytic copper foil as a carrier, it is preferable to provide an intermediate layer on the shiny surface from the viewpoint of reducing pinholes.

Among the intermediate layers, the chromate layer is thin at the interface of the ultrathin copper layer, while the ultrathin copper layer does not peel from the carrier before the lamination process to the insulating substrate, while the carrier after the lamination process to the insulating substrate From the viewpoint of obtaining the property that the ultrathin copper layer can be peeled off. When the chromate layer is present at the boundary between the carrier and the ultrathin copper layer without providing the nickel layer, the peelability is hardly improved, and when there is no chromate layer and the nickel layer and the ultrathin copper layer are laminated directly, nickel Depending on the amount of nickel in the layer, the peel strength is too strong or too weak to obtain an appropriate peel strength.

Also, if the chromate layer is present at the boundary between the carrier and the nickel layer, the intermediate layer is also peeled along with the peeling of the ultrathin copper layer, that is, peeling occurs between the carrier and the intermediate layer. Such a situation can occur not only when the chromate layer is provided at the interface with the carrier, but also when the amount of chromium is excessive even if the chromate layer is provided at the interface with the ultrathin copper layer. This is because copper and nickel are likely to be in solid solution, so if they are in contact with each other, the adhesive force increases due to mutual diffusion and is difficult to peel off, while chromium and copper are less likely to dissolve and cause mutual diffusion. It is considered that the adhesion between the chromium and copper interface is weak and easy to peel off. Further, when the nickel amount in the intermediate layer is insufficient, there is only a very small amount of chromium between the carrier and the ultrathin copper layer, so that they are in close contact with each other and are difficult to peel off.

The nickel of the intermediate layer can be formed by wet plating such as electroplating, electroless plating and immersion plating, or dry plating such as sputtering, CVD and PDV. Electroplating is preferable from the viewpoint of cost.
Also, chromate can be formed with, for example, electrolytic chromate, immersion chromate, etc., but the chromium concentration can be increased, and the peel strength of the ultrathin copper layer from the copper foil carrier is improved. Preferably formed.

In the intermediate layer, the adhesion amount of nickel is 100 to 40000 μg / dm ² , and the adhesion amount of chromium is 5 to 100 μg / dm ² . Although the amount of pinholes tends to increase as the amount of nickel increases, the number of pinholes is also suppressed within this range. From the viewpoint of evenly peeling the ultrathin copper layer uniformly and from the viewpoint of suppressing pinholes, the nickel adhesion amount is preferably 300 to 10,000 μg / dm ^2, and preferably 500 to 3000 μg / dm ^2. More preferably, the chromium adhesion amount is preferably 10 to 50 μg / dm ² , more preferably 12 to 30 μg / dm ² .

<3. Strike plating>
An ultrathin copper layer is provided on the intermediate layer. Before that, strike plating with a copper-phosphorus alloy may be performed to reduce pinholes in the ultrathin copper layer. Examples of the strike plating include a copper pyrophosphate plating solution.

<4. Ultra-thin copper layer>
An ultrathin copper layer is provided on the intermediate layer. The ultra-thin copper layer can be formed by electroplating using an electrolytic bath such as copper sulfate, copper pyrophosphate, copper sulfamate, copper cyanide, etc., and is used in general electrolytic copper foil with high current density. Since a copper foil can be formed, a copper sulfate bath is preferable. The thickness of the ultrathin copper layer is not particularly limited, but is generally thinner than the carrier, for example, 12 μm or less. Typically 0.5 to 12 μm, more typically 2 to 5 μm.

<5. Roughening>
A roughening treatment layer may be provided on the surface of the ultrathin copper layer by performing a roughening treatment, for example, in order to improve the adhesion to the insulating substrate. 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 may be a single layer selected from the group consisting of copper, nickel, cobalt and zinc, or a layer made of an alloy containing one or more of them. In addition, after roughening treatment or without roughening treatment, secondary particles, tertiary particles and / or rust preventive layers are formed of nickel, cobalt, copper, zinc alone or an alloy, and further on the surface. Treatments such as chromate treatment and silane coupling treatment may be applied. That is, on the surface of the roughening treatment layer, one or more layers selected from the group consisting of a rust prevention layer, a chromate treatment layer and a silane coupling treatment layer may be formed, and on the surface of the ultrathin copper layer, You may form 1 or more types of layers selected from the group which consists of a rust prevention layer, a chromate treatment layer, and a silane coupling treatment layer.

<6. Copper foil with carrier>
Thus, the copper foil with a carrier provided with the copper foil carrier, the intermediate | middle layer formed on the copper foil carrier, and the ultra-thin copper layer laminated | stacked on the intermediate | middle layer is manufactured. How to use the copper foil with carrier itself is well known to those skilled in the art. For example, the surface of the ultra-thin copper layer is made of paper base phenol resin, paper base epoxy resin, synthetic fiber cloth base epoxy resin, glass cloth / paper composite. A copper-clad laminate can be obtained by bonding to an insulating substrate such as a base epoxy resin, glass cloth / glass nonwoven fabric composite base epoxy resin and glass cloth base epoxy resin, polyester film, polyimide film, etc., and peeling the carrier after thermocompression bonding. Further, an ultrathin copper layer bonded to the insulating substrate of the copper-clad laminate can be etched into a target conductor pattern, and finally a printed wiring board or a printed circuit board can be manufactured. In the case of the copper foil with a carrier according to the present invention, the peeled portion is mainly the interface between the intermediate layer and the ultrathin copper layer.

When the copper foil with a carrier of the present invention is peeled between the intermediate layer / ultra thin copper layer, the atomic concentration of chromium in the depth direction (x: unit nm) obtained from the depth direction analysis from the surface by XPS ( %) Is f (x), nickel atomic concentration (%) is g (x), copper atomic concentration (%) is h (x), and oxygen total atomic concentration (%) is i (x). And the atomic concentration (%) of carbon is j (x) and the other atomic concentration (%) is k (x), in the interval [0, 1.0] of the depth direction analysis from the intermediate layer surface , ∫f (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) Is 1-30%, ∫g (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k When (x) dx) is 1 to 50% and [1.0, 4.0], ∫g (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) satisfies 40% or more.
Further, when the copper foil with a carrier of the present invention is peeled between the intermediate layer / ultra-thin copper layer, in the section [0, 1.0] in the depth direction analysis from the intermediate layer surface by XPS, ∫f (x ) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) is 2-25% It is preferable to satisfy.
Moreover, the copper foil with a carrier of the present invention is obtained by thermocompression bonding an insulating substrate to an ultrathin copper layer under the conditions of pressure: 20 kgf / cm ² , 220 ° C. × 2 hours between the intermediate layer and the ultrathin copper layer. When exfoliated, the atomic concentration (%) of chromium in the depth direction (x: unit nm) obtained from XPS depth direction analysis is defined as f (x), and the atomic concentration (%) of nickel is g (x), copper atomic concentration (%) as h (x), oxygen total atomic concentration (%) as i (x), carbon atomic concentration (%) as j (x), etc. In the interval [0, 1.0] of the depth direction analysis from the intermediate layer surface, ∫f (x) dx / (∫f (x) dx + ∫ g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) is 0.5-30%, ∫g (x) dx / (∫ f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) is 1 to 50%, and [1. 0, 4.0], ∫g (x) dx / ( ∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx +) k (x) dx) preferably satisfies 40% or more. .
Moreover, the copper foil with a carrier of the present invention is obtained by thermocompression bonding an insulating substrate to an ultrathin copper layer under the conditions of pressure: 20 kgf / cm ² and 220 ° C. × 2 hours between the intermediate layer and the ultrathin copper layer. When exfoliated, 区間 f (x) dx / (∫f (x) dx + ∫g (x) dx + ∫ in the section [0, 1.0] in the depth direction analysis from the intermediate layer surface by XPS h (x) dx +) i (x) dx + ∫j (x) dx + ∫k (x) dx) preferably satisfies 1 to 25%.
Thus, in the copper foil with a carrier of the present invention, chromium is present in a certain amount or more on the outermost surface of the intermediate layer when peeled between the intermediate layer / ultra-thin copper layer, and nickel is present inside the outermost surface. The concentration is high. For this reason, generation | occurrence | production of the pinhole in an ultra-thin copper layer side surface is suppressed favorably. Also, in the copper foil with carrier after thermocompression bonding, chromium is present in a certain amount or more on the outermost surface of the intermediate layer when the copper foil carrier is peeled from the ultrathin copper layer, and nickel is more than the outermost surface. The concentration is high inside. For this reason, generation | occurrence | production of the pinhole in an ultra-thin copper layer side surface is suppressed favorably.

When the copper foil with carrier of the present invention is peeled between the intermediate layer / ultra-thin copper layer, in the section [1.0, 4.0] of the depth direction analysis from the intermediate layer surface by XPS, ∫h (x ) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) is 1-30% It is preferable to satisfy.
Moreover, the copper foil with a carrier of the present invention is obtained by thermocompression bonding an insulating substrate to an ultrathin copper layer under the conditions of pressure: 20 kgf / cm ² , 220 ° C. × 2 hours between the intermediate layer and the ultrathin copper layer. When exfoliated, 区間 h (x) dx / (∫f (x) dx + ∫g (x) dx in the section [1.0, 4.0] of depth direction analysis from the intermediate layer surface by XPS + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) preferably satisfies 2 to 40%.
Thus, in the copper foil with a carrier of the present invention, copper is present in a certain amount or more inside the intermediate layer when peeled between the intermediate layer / ultra thin copper layer. As the copper concentration in the intermediate layer increases, the adhesion between the intermediate layer and the ultrathin copper layer increases. Therefore, the peel strength can be controlled by controlling the copper concentration in nickel. Moreover, also in the copper foil with a carrier after thermocompression bonding, copper exists in a certain amount or more inside the intermediate layer when the copper foil carrier is peeled from the ultrathin copper layer. For this reason, there exists an effect that the fall of the extreme peeling strength after thermocompression-bonding can be prevented.
The higher the nickel current density is set to increase the electrodeposition rate per unit time, and the higher the transport speed of the carrier copper foil, the lower the density of the nickel layer. When the density of the nickel layer is reduced, the copper of the carrier copper foil is easily diffused into the nickel layer, and the concentration of copper in the nickel can be controlled. Further, when the current density in the chromate treatment is increased and the conveying speed of the carrier copper foil is decreased, the chromium concentration increases and the chromium concentration can be controlled.

Further, in the copper foil with a carrier of the present invention, it is preferable that the binding energy of the 2P3 / 2 orbit of chromium detected by XPS in the intermediate layer is in the range of 576 to 580 eV. According to such a configuration, chromium present in the intermediate layer becomes not chromium metal but chromium oxide, and the generation of pinholes on the surface of the ultrathin copper layer can be suppressed more favorably.

Hereinafter, the present invention will be described in more detail with reference to examples of the present invention, but the present invention is not limited to these examples.

1. Production of Copper Foil with Carrier As a copper foil carrier, a long electrolytic copper foil having a thickness of 35 μm (JTC made by JX Nippon Mining & Metals) and a rolled copper foil having a thickness of 33 μm (C1100 made by JX Nippon Mining & Metals) Prepared. With respect to the shiny surface of this copper foil, the intermediate layer forming process described in Tables 1 and 2 is performed in the following conditions in order on the carrier surface and the ultrathin copper layer side in a roll-to-roll type continuous line under the following conditions. went. Washing and pickling were performed between the processing steps on the carrier surface side and the ultrathin copper layer side.

・ Ni plating Nickel sulfate: 250-300 g / L
Nickel chloride: 35 to 45 g / L
Nickel acetate: 10-20g / L
Trisodium citrate: 15-30 g / L
Brightener: Saccharin, butynediol, etc. Sodium dodecyl sulfate: 30 to 100 ppm
pH: 4-6
Bath temperature: 50-70 ° C
Current density: 3 to 15 A / dm ²

-Cr plating solution composition: chromic anhydride 200-400 g / L, sulfuric acid 1.5-4 g / L
pH: 1 to 4
Liquid temperature: 45-60 ° C
Current density: 10 to 40 A / dm ²

・ Immersion chromate treatment Liquid composition (1): Potassium dichromate 1-10 g / L, Zinc 0-5 g / L
Liquid composition (2): chromic anhydride 1-10 g / L
pH: 3-4
Liquid temperature: 50-60 ° C
Immersion time: 1 to 20 seconds

Electrolytic chromate treatment Liquid composition (1): Potassium dichromate 1-10 g / L, Zinc 0-5 g / L
Liquid composition (2): chromic anhydride 1-10 g / L
pH: 3-4
Liquid temperature: 50-60 ° C
Current density: 0.1 to 2.6 A / dm ²
Coulomb amount: 0.5-30 As / dm ²

Subsequently, an ultrathin copper layer having a thickness of 35 μm was formed on the intermediate layer on the roll-to-roll-type continuous plating line by electroplating under the following conditions to produce a copper foil with a carrier. For Examples 1 to 3, 5, 7, 11, and 13 to 15, copper foils with a carrier having ultrathin copper layers with thicknesses of 1, 2, 3, 5, and 12 μm were also produced.
・ Ultra-thin copper layer Copper concentration: 30-120 g / L
H ₂ SO ₄ concentration: 20 to 120 g / L
Electrolyte temperature: 20-80 ° C
Current density: 10 to 100 A / dm ²

In Examples 2, 3, 7, and 11, the surface of the ultrathin copper layer was subjected to the following roughening treatment, rust prevention treatment, chromate treatment, and silane coupling treatment in this order.
・ Roughening treatment Cu: 10 to 20 g / L
Co: 1 to 10 g / L
Ni: 1 to 10 g / L
pH: 1-4
Temperature: 40-50 ° C
Current density Dk: 20 to 30 A / dm ²
Time: 1-5 seconds Cu adhesion amount: 15-40 mg / dm ²
Co adhesion amount: 100 to 3000 μg / dm ²
Ni adhesion amount: 100 to 1000 μg / dm ²
・ Rust prevention treatment Zn: 0-20g / L
Ni: 0-5g / L
pH: 3.5
Temperature: 40 ° C
Current density Dk: 0 to 1.7 A / dm ²
Time: 1 second Zn deposition amount: 5 to 250 μg / dm ²
Ni adhesion amount: 5 to 300 μg / dm ²
・ Chromate treatment K ₂ Cr ₂ O ₇
(Na ₂ Cr ₂ O ₇ or CrO ₃ ): 2 to 10 g / L
NaOH or KOH: 10-50g / L
ZnO or ZnSO ₄ 7H ₂ O: 0.05 to 10 g / L
pH: 7-13
Bath temperature: 20-80 ° C
Current density 0.05-5A / dm ²
Time: 5 to 30 seconds Cr adhesion amount: 10 to 150 μg / dm ²
・ Silane coupling treatment Vinyltriethoxysilane aqueous solution (vinyltriethoxysilane concentration: 0.1 to 1.4 wt%)
pH: 4-5
Time: 5-30 seconds

2. Various evaluations of copper foil with carrier Various evaluations were carried out by the following methods for the copper foil with carrier obtained as described above. The results are shown in Tables 1 and 2.

<Measurement of adhesion amount>
The amount of nickel deposited is measured by ICP emission analysis after dissolving the sample in nitric acid with a concentration of 20% by mass. The amount of chromium deposited is quantitatively analyzed by atomic absorption spectrometry after dissolving the sample in 7% by mass of hydrochloric acid. Measured with

<XPS analysis>
After bonding the ultrathin copper layer side of the copper foil with a carrier on an insulating substrate and performing pressure bonding under the conditions of 20 kgf / cm ² and 220 ° C. × 2 hours, the copper foil carrier is peeled off from the ultrathin copper layer. It was. Subsequently, the exposed intermediate layer surface was subjected to XPS measurement to create a depth profile. XPS operating conditions are shown below.
・ Device: XPS measuring device (ULVAC-PHI, Model 5600MC)
・ Achieved vacuum: 3.8 × 10 ⁻⁷ Pa
X-ray: Monochromatic AlKα or non-monochromatic MgKα, X-ray output 300 W, detection area 800 μmφ, angle between sample and detector 45 °
Ion beam: ion species Ar ⁺ , acceleration voltage 3 kV, sweep area 3 mm × 3 mm, sputtering rate 2.8 nm / min (in terms of SiO ₂ )
Moreover, also about the copper foil with a carrier before the said thermocompression bonding, the copper foil carrier was peeled off from the ultra-thin copper layer, the XPS measurement was performed for the exposed copper foil carrier surface, and the depth profile was created.
In addition, whether it peeled between the intermediate | middle layer and the ultra-thin copper layer can be confirmed by producing the depth profile of the ultra-thin copper layer side like the intermediate | middle layer side. As shown in FIG. 3, nickel and chromium, which are constituent elements on the intermediate layer side, are hardly detected on the ultrathin copper foil side. When the atomic concentrations of nickel and chromium on the ultrathin copper layer side surface were each 5 at% or less, it was determined that the intermediate layer and the ultrathin copper layer were separated.
Further, the binding energy of the 2P3 / 2 orbit of chromium in the intermediate layer was detected by XPS.

<Pinhole>
The number of pinholes was visually measured using a consumer photographic backlight as a light source.

<Peel strength>
After bonding the ultra-thin copper layer side of the copper foil with carrier on the insulating substrate and performing pressure bonding under the conditions of 20 kgf / cm ² and 220 ° C. × 2 hours in the atmosphere, the peel strength is measured with a load cell. The foil carrier side was pulled and measured according to the 180 ° peeling method (JIS C 6471 8.1). Further, the peel strength of the carrier-attached copper foil before being bonded onto the insulating substrate was also measured.

(Evaluation results)
In all of Examples 1 to 15, pinholes were well suppressed, and even better peel strength was exhibited. In addition, the copper foil with a carrier whose thickness of the ultra-thin copper layer produced for each of Examples 1 to 3, 5, 7, 11, and 13 to 15 is 1, 2, 3, 5, and 12 μm is also an ultra-thin copper layer. The results were the same as when the thickness of the film was 35 μm, and in all cases, pinholes were well suppressed, and even better peel strength was exhibited.
In Comparative Examples 1 and 2, the intermediate layer was not formed, and the adhesion amount of nickel and chromium was small, so that the carrier could not be peeled from the ultrathin copper layer even before thermocompression bonding.
In Comparative Examples 4, 5, 6, and 9, since the adhesion amount of nickel was small, the carrier could not be peeled from the ultrathin copper layer even before thermocompression bonding.
In Comparative Examples 3, 8, and 10, since the amount of chromium attached was small, the carrier could not be peeled after bonding to the substrate.
In Comparative Example 7, since the amount of nickel deposited was too large, pinholes in the ultrathin copper layer increased and the peel strength was too low.
Since Comparative Examples 11 to 13 used chrome plating instead of chromate, many pinholes were generated.
In Comparative Example 14, since the concentration of nickel on the surface of the intermediate layer formed on the carrier was high, the number of pinholes was increased and the peel strength was too low.
In Comparative Example 15, since the amount of chromium deposited was large, pinholes in the ultrathin copper layer occurred frequently, and the peel strength was too low.
FIG. 1 and FIG. 2 show XPS depth profiles in the depth direction of the surface of the intermediate layer before bonding the substrates of Example 2 and Comparative Example 3, respectively. FIG. 3 shows an XPS depth profile in the depth direction of the surface of the ultrathin copper layer before bonding the substrates in Example 2.
In addition, about the Example and comparative example which were able to peel an ultra-thin copper layer from a carrier, all peeled between the intermediate | middle layer and the ultra-thin copper layer.

Claims

A copper foil with a carrier comprising a copper foil carrier, an intermediate layer laminated on the copper foil carrier, and an ultrathin copper layer laminated on the intermediate layer,
The intermediate layer is configured by laminating nickel and chromate in this order on the copper foil carrier,
Adhesion amount 100 ~ 40000μg / dm 2 of nickel, the adhesion amount of chromium is 5 ~ 100μg / dm 2,
When peeling between the intermediate layer and ultrathin copper layer, the atomic concentration (%) of chromium in the depth direction (x: unit nm) obtained from the depth direction analysis from the surface by XPS is defined as f (x). The atomic concentration (%) of nickel is g (x), the atomic concentration (%) of copper is h (x), the total atomic concentration (%) of oxygen is i (x), and the atomic concentration of carbon (% ) Is j (x) and other atomic concentration (%) is k (x),
In the section [0, 1.0] of the depth direction analysis from the intermediate layer surface, ∫f (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) is 1-30%, ∫g (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) is 1 to 50%, and [1.0, 4.0], ∫g (x) dx / With carrier satisfying (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) Copper foil.
When delamination is performed between the intermediate layer and the ultrathin copper layer, ∫f (x) dx / (∫f (x) in the section [0, 1.0] in the depth direction analysis from the intermediate layer surface by XPS The carrier according to claim 1, wherein dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) satisfies 2 to 25%. Copper foil.
When peeling between the intermediate layer / ultra-thin copper layer, in the section [1.0, 4.0] of the depth direction analysis from the intermediate layer surface by XPS, ∫h (x) dx / (∫f ( x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) satisfy 1-30% The copper foil with a carrier as described in 2.
The copper foil with a carrier according to any one of claims 1 to 3, wherein the binding energy of the 2P3 / 2 orbit of chromium detected by XPS of the intermediate layer is within a range of 576 to 580 eV.
When the insulating substrate is thermocompression bonded to the ultrathin copper layer under the conditions of pressure: 20 kgf / cm 2 , 220 ° C. × 2 hours in the atmosphere, and peeled between the intermediate layer / ultrathin copper layer, the surface by XPS The atomic concentration (%) of chromium in the depth direction (x: unit nm) obtained from the analysis of the depth direction of copper is f (x), the atomic concentration (%) of nickel is g (x), and copper atoms The concentration (%) is h (x), the total atomic concentration (%) of oxygen is i (x), the atomic concentration (%) of carbon is j (x), and the other atomic concentration (%) is k ( x)
In the section [0, 1.0] of the depth direction analysis from the intermediate layer surface, ∫f (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) is 0.5-30%, ∫g (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) is 1 to 50% and [1.0, 4.0], ∫g (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i (x) dx + ∫j (x) dx + ∫k (x) dx) satisfies 40% or more The copper foil with a carrier according to any one of claims 1 to 4.
When the insulating substrate is thermocompression bonded to the ultrathin copper layer under the conditions of pressure: 20 kgf / cm 2 , 220 ° C. × 2 hours in the atmosphere and peeled between the intermediate layer / ultrathin copper layer, the intermediate by XPS In the interval [0, 1.0] of the depth direction analysis from the layer surface, ∫f (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + ∫i 6. The copper foil with a carrier according to claim 1, wherein (x) dx +) j (x) dx + ∫k (x) dx) satisfies 1 to 25%.
When the insulating substrate is thermocompression bonded to the ultrathin copper layer under the conditions of pressure: 20 kgf / cm 2 , 220 ° C. × 2 hours in the atmosphere and peeled between the intermediate layer / ultrathin copper layer, the intermediate by XPS In the section [1.0, 4.0] of the depth direction analysis from the layer surface, ∫h (x) dx / (∫f (x) dx + ∫g (x) dx + ∫h (x) dx + The copper foil with a carrier according to any one of claims 1 to 6, wherein (i (x) dx + (j (x) dx + (k) (x) dx)) satisfies 2 to 40%.
The carrier-attached copper foil according to any one of claims 1 to 7, wherein the copper foil carrier is formed of an electrolytic copper foil or a rolled copper foil.
The carrier-attached copper foil according to any one of claims 1 to 8, further comprising a roughened layer on the surface of the ultrathin copper layer.
10. The copper foil with a carrier according to claim 9, wherein the roughening layer is a layer made of any single element selected from the group consisting of copper, nickel, cobalt, and zinc, or an alloy containing any one or more of them.
The copper foil with a carrier according to claim 9 or 10, wherein the surface of the roughening treatment layer has one or more layers selected from the group consisting of a rust prevention layer, a chromate treatment layer and a silane coupling treatment layer.
The copper with carrier according to any one of claims 1 to 8, wherein the ultrathin copper layer has one or more layers selected from the group consisting of a rust prevention layer, a chromate treatment layer, and a silane coupling treatment layer on the surface of the ultrathin copper layer. Foil.
After forming nickel plating on the copper foil carrier, including a step of forming an intermediate layer by forming a chromate layer by electrolytic chromate, and a step of forming an ultrathin copper layer by electrolytic plating on the intermediate layer The manufacturing method of copper foil with a carrier.
Forming a nickel plating on the copper foil carrier, and then forming an intermediate layer by forming a chromate layer by electrolytic chromate; forming an ultrathin copper layer by electrolytic plating on the intermediate layer; and The manufacturing method of copper foil with a carrier including the process of forming a roughening process layer on an ultra-thin copper layer.
A printed wiring board manufactured using the carrier-attached copper foil according to any one of claims 1 to 12.
A printed circuit board manufactured using the carrier-attached copper foil according to any one of claims 1 to 12.
A copper-clad laminate produced using the carrier-attached copper foil according to any one of claims 1 to 12.