JP6329731B2 - Copper foil with carrier, method for producing copper-clad laminate, and method for producing printed wiring board - Google Patents

Description

  The present invention relates to a copper foil with a carrier, a printed wiring board, a printed circuit board, a copper-clad laminate, and a method for producing a printed wiring board, and in particular, a copper foil with a carrier used when producing a printed wiring board for a fine pattern, It is related with the manufacturing method of a wiring board, a printed circuit board, a copper clad laminated board, and a printed wiring board.

  Generally, a printed wiring board is manufactured through a process in which an insulating substrate is bonded to a copper foil to form a copper-clad laminate, and then a conductor pattern is formed on the copper foil surface by etching. In recent years, with the increasing needs for miniaturization and higher 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 higher frequency than printed circuit boards. Response is required.

  Recently, copper foils with a thickness of 9 μm or less and further with a thickness of 5 μm or less have been required in response to the fine pitch, but such ultra-thin copper foils have low mechanical strength and are used in the manufacture of printed wiring boards. Copper foil with a carrier has appeared, in which a thick metal foil is used as a carrier, and an ultrathin copper layer is electrodeposited through a release layer, since it is easily broken or wrinkled. After bonding the surface of the ultrathin copper layer to an insulating substrate and thermocompression bonding, the carrier is peeled and removed through the peeling layer. After forming a circuit pattern with a resist on the exposed ultrathin copper layer, the ultrathin copper layer is etched away with a sulfuric acid-hydrogen peroxide etchant (MSAP: Modified-Semi-Additive-Process). Is formed.

  Here, for the surface of the ultra-thin copper layer of the copper foil with carrier, which becomes the adhesive surface with the resin, the peel strength between the ultra-thin copper layer and the resin substrate is mainly sufficient, and the peel strength Is required to be sufficiently retained after high-temperature heating, wet processing, soldering, chemical processing, and the like. As a method of increasing the peel strength between the ultrathin copper layer and the resin base material, generally, a large amount of roughened particles are adhered on the ultrathin copper layer having a large surface profile (unevenness, roughness). The method is representative.

  However, if a very thin copper layer with such a large profile (irregularity, roughness) is used on a semiconductor package substrate that needs to form a particularly fine circuit pattern among printed wiring boards, unnecessary copper particles during circuit etching Will remain, causing problems such as poor insulation between circuit patterns.

  For this reason, Patent Document 1 attempts to use a copper foil with a carrier that is not subjected to roughening treatment on the surface of an ultrathin copper layer as a copper foil with a carrier for use in a fine circuit including a semiconductor package substrate. . The adhesion (peeling strength) between the ultrathin copper layer not subjected to such roughening treatment and the resin is affected by the low profile (unevenness, roughness, roughness) of the general copper foil for printed wiring boards. There is a tendency to decrease when compared. Therefore, the further improvement is calculated | required about copper foil with a carrier.

  Therefore, in Patent Document 2 and Patent Document 3, an Ni layer or / and an Ni alloy layer are provided on a surface that comes into contact (adhesion) with the polyimide resin substrate of the ultrathin copper foil with a carrier, a chromate layer is provided, Cr It is described that a layer or / and a Cr alloy layer are provided, a Ni layer and a chromate layer are provided, and a Ni layer and a Cr layer are provided. By providing these surface treatment layers, the adhesion strength between the polyimide resin substrate and the ultra-thin copper foil with carrier is not roughened, or the desired peel strength is achieved while reducing (miniaturizing) the level of the roughening treatment. It has gained. Further, it is described that the surface treatment is performed with a silane coupling agent or the rust prevention treatment is performed.

  In addition, as a technique for improving the peelability after adhesion between the copper foil and the resin, Patent Document 4 discloses that after the surface of the copper foil is roughened by copper-cobalt-nickel alloy plating, a cobalt plating layer or cobalt-nickel is used. A method for forming an alloy plating layer is disclosed. This is a copper foil treatment method in which a cobalt-nickel alloy plating layer is formed on the surface of the copper foil after a roughening treatment by copper-cobalt-nickel alloy plating, and further a zinc-nickel alloy plating layer is formed. It is a very effective invention and has become one of the main products of copper foil circuit materials today.

  There are many inventors about the surface treatment of the copper foil which forms the cobalt-nickel alloy plating layer after the roughening process by copper-cobalt-nickel alloy plating on the surface of the copper foil, and further forms the zinc-nickel alloy plating layer. There have been some major advances in improving the properties of copper foil. The initial techniques of the roughening treatment by copper-cobalt-nickel alloy plating are disclosed in Patent Document 5, Patent Document 6, and Patent Document 7.

WO2004 / 005588 JP 2007-007937 A JP 2010-006071 A Japanese Patent Publication No. 6-54831 Japanese Patent No. 2849059 Japanese Patent Laid-Open No. 4-96395 JP-A-10-18075

  However, the conventional copper foil formed with a cobalt-nickel alloy plating layer has a dendritic shape of roughened particles made of copper-cobalt-nickel alloy plating formed on the surface thereof, so It peeled off from the roots and caused a problem commonly referred to as the powdering phenomenon.

  This powder-off phenomenon is a troublesome problem, and the roughened layer of copper-cobalt-nickel alloy plating has excellent adhesion to the resin layer and is also excellent in heat resistance. Nevertheless, the particles easily fall off due to an external force, causing problems such as peeling due to “rubbing” during processing, contamination of the roll with peeling powder, and etching residue due to peeling powder.

  Therefore, the present invention provides a phenomenon in which the peel strength between the ultrathin copper layer and the resin base material is good and the roughened particles formed on the surface of the ultrathin copper layer peel off from the surface, so-called “powder off”. It is an object of the present invention to provide a carrier-attached copper foil whose generation is satisfactorily suppressed.

  The inventor forms a predetermined roughened particle layer on the surface of the ultrathin copper layer of the copper foil with carrier, and controls the ratio of the three-dimensional surface area to the two-dimensional surface area of the roughened particle layer. The present inventors have found that it is extremely effective for the peel strength between the ultrathin copper layer of the attached copper foil and the resin substrate and the suppression of powder falling on the surface of the ultrathin copper layer.

The present invention has been completed on the basis of the above knowledge, and in one aspect, a carrier, an intermediate layer, a copper foil with a carrier in which an ultrathin copper layer is laminated in this order, and on the surface of the ultrathin copper layer, having a primary particle layer on top of the primary particles layer has a secondary particle layer, three-dimensional relative two-dimensional surface area, as measured using a laser microscope of the surface forming the primary particles layer and the secondary particle layer It is a copper foil with a carrier whose surface area ratio is 2.03 or more and less than 2.2.

The present invention in another aspect is a method for producing a print wiring board using the copper foil with carrier of the present invention.

The present invention in yet another aspect, a method of producing a copper-clad laminate using a copper foil with carrier of the present invention.

  In yet another aspect of the present invention, the step of preparing the copper foil with carrier and the insulating substrate of the present invention, the step of laminating the copper foil with carrier and the insulating substrate, the copper foil with carrier and the insulating substrate, After the lamination, a copper-clad laminate is formed through a step of peeling the carrier of the copper foil with carrier, and then the circuit is formed by any of the semi-additive method, the subtractive method, the partial additive method, or the modified semi-additive method. It is a manufacturing method of a printed wiring board including the process of forming.

  According to the present invention, the peel strength between the ultrathin copper layer and the resin base material is good, and the roughened particles formed on the surface of the ultrathin copper layer are peeled off from the surface, so-called “powder off”. It is possible to provide a copper foil with a carrier in which generation is satisfactorily suppressed.

It is a conceptual explanatory drawing which shows the mode of the powder fall at the time of performing the roughening process which consists of copper-cobalt-nickel alloy plating on the conventional copper foil. Conceptual explanation of a copper foil treatment layer without powder falling, in which a primary particle layer is formed in advance on a copper foil and a secondary particle layer made of copper-cobalt-nickel alloy plating is formed on the primary particle layer of the present invention. FIG. It is the microscope picture of the surface at the time of performing the roughening process which consists of copper-cobalt-nickel alloy plating on the conventional copper foil. The primary particle layer is previously formed on the copper foil of the present invention, and the secondary particle layer made of copper-cobalt-nickel alloy plating is formed on the primary particle layer. It is a micrograph.

<Career>
Carriers that can be used in the present invention are typically metal foils or resin films, such as copper foil, copper alloy foil, nickel foil, nickel alloy foil, iron foil, iron alloy foil, stainless steel foil, aluminum foil, aluminum. It is provided in the form of alloy foil, insulating resin film, polyimide film, LCP (liquid crystal polymer) film, and fluororesin film.
Carriers that can be used in the present invention are 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. Examples of copper foil materials include high-purity copper such as tough pitch copper (JIS H3100 alloy number C1100) and oxygen-free copper (JIS H3100 alloy number C1020 or JIS H3510 alloy number C1011), for example, Sn-containing copper, Ag-containing copper, Cr A copper alloy such as a copper alloy added with Zr or Mg, or a Corson copper alloy added with Ni, Si or the like 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, and may be, for example, 5 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 8 to 70 μm, more typically 12 to 70 μm, and more typically 18 to 35 μm. Moreover, it is preferable that the thickness of a carrier is small from a viewpoint of reducing raw material cost. Therefore, the thickness of the carrier is typically 5 μm or more and 35 μm or less, preferably 5 μm or more and 18 μm or less, preferably 5 μm or more and 12 μm or less, preferably 5 μm or more and 11 μm or less, preferably 5 μm or more and 10 μm or less. It is as follows. In addition, when the thickness of a carrier is small, it is easy to generate | occur | produce a wrinkle in the case of a carrier foil. In order to prevent the generation of folding wrinkles, for example, it is effective to smooth the transport roll of the copper foil manufacturing apparatus with a carrier and to shorten the distance between the transport roll and the next transport roll.

<Intermediate layer>
An intermediate layer is provided on one or both sides of the carrier. In the intermediate layer used in the present invention, the ultrathin copper layer is hardly peeled off from the carrier before the copper foil with the carrier is laminated on the insulating substrate, while the ultrathin copper layer is separated from the carrier after the lamination step on the insulating substrate. There is no particular limitation as long as it can be peeled off. For example, the intermediate layer of the copper foil with a carrier of the present invention is Cr, Ni, Co, Fe, Mo, Ti, W, P, Cu, Al, Zn, alloys thereof, hydrates thereof, oxides thereof, One or two or more selected from the group consisting of organic substances may be included. The intermediate layer may be a plurality of layers.

  Further, for example, the intermediate layer is a single metal layer composed of one kind of element selected from the element group composed of Cr, Ni, Co, Fe, Mo, Ti, W, P, Cu, Al, Zn from the carrier side. Or forming an alloy layer composed of one or more elements selected from the group consisting of Cr, Ni, Co, Fe, Mo, Ti, W, P, Cu, Al, Zn, A layer made of a hydrate or oxide of one or more elements selected from the group consisting of Cr, Ni, Co, Fe, Mo, Ti, W, P, Cu, Al, and Zn. It can comprise by forming.

  When the intermediate layer is provided only on one side, it is preferable to provide a rust preventive layer such as a Ni plating layer on the opposite side of the carrier. When the intermediate layer is provided by chromate treatment, zinc chromate treatment, or plating treatment, it is considered that some of the attached metal such as chromium and zinc may be hydrates or oxides.

Further, for example, the intermediate layer can be configured by laminating nickel, a nickel-phosphorus alloy or a nickel-cobalt alloy, and chromium in this order on a 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 chromium. 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. Adhesion amount of nickel in the intermediate layer is preferably 100 [mu] g / dm ² or more 40000μg / dm ² or less, more preferably 100 [mu] g / dm ² or more 4000μg / dm ² or less, more preferably 100 [mu] g / dm ² or more 2500 g / dm ² or less, more Preferably, it is 100 μg / dm ² or more and less than 1000 μg / dm ² , and the amount of chromium deposited on the intermediate layer is preferably 5 μg / dm ² or more and 100 μg / dm ² or less. When the intermediate layer is provided only on one side, it is preferable to provide a rust preventive layer such as a Ni plating layer on the opposite side of the carrier.

  Further, an intermediate layer containing Ni may be provided on one side or both sides of the carrier. The intermediate layer is formed by laminating any one layer of nickel or an alloy containing nickel on the carrier and a layer containing any one or more of chromium, a chromium alloy, and an oxide of chromium in this order. It is preferable. In addition, it is preferable that zinc is contained in any one layer of nickel or an alloy containing nickel and / or a layer containing any one or more of chromium, a chromium alloy, and an oxide of chromium. Here, the alloy containing nickel is composed of nickel and one or more elements selected from the group consisting of cobalt, iron, chromium, molybdenum, zinc, tantalum, copper, aluminum, phosphorus, tungsten, tin, arsenic, and titanium. An alloy. The alloy containing nickel may be an alloy composed of three or more elements. The chromium alloy is an alloy composed of chromium and one or more elements selected from the group consisting of cobalt, iron, nickel, molybdenum, zinc, tantalum, copper, aluminum, phosphorus, tungsten, tin, arsenic, and titanium. Say. The chromium alloy may be an alloy composed of three or more elements. Further, the layer containing any one or more of chromium, a chromium alloy, and a chromium oxide may be a chromate treatment layer. Here, the chromate-treated layer refers to a layer treated with a liquid containing chromic anhydride, chromic acid, dichromic acid, chromate or dichromate. Chromate treatment layer is any element such as cobalt, iron, nickel, molybdenum, zinc, tantalum, copper, aluminum, phosphorus, tungsten, tin, arsenic and titanium (metal, alloy, oxide, nitride, sulfide, etc.) May be included). Specific examples of the chromate treatment layer include a pure chromate treatment layer and a zinc chromate treatment layer. In the present invention, a chromate treatment layer treated with an anhydrous chromic acid or potassium dichromate aqueous solution is referred to as a pure chromate treatment layer. In the present invention, a chromate treatment layer treated with a treatment liquid containing chromic anhydride or potassium dichromate and zinc is referred to as a zinc chromate treatment layer.

  In addition, the intermediate layer is any one of nickel, nickel-zinc alloy, nickel-phosphorus alloy, nickel-cobalt alloy, zinc chromate treatment layer, pure chromate treatment layer, and chromium plating layer on the carrier. It is preferable that one kind of layer is laminated in this order, and the intermediate layer is constituted by laminating a nickel layer or a nickel-zinc alloy layer and a zinc chromate treatment layer in this order on the carrier. It is more preferable that the nickel-zinc alloy layer and the pure chromate-treated layer or the zinc chromate-treated layer are laminated in this order. Since the adhesive force between nickel and copper is higher than the adhesive force between chromium and copper, when the ultrathin copper layer is peeled off, it peels at the interface between the ultrathin copper layer and the chromate treatment layer. 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. Further, it is preferable to form a chromate treatment layer 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. The surface on which the chromate treatment layer is formed has a chromium oxide layer that is less dense than chrome plating, so resistance to formation of ultrathin copper foil by electroplating is less likely to reduce pinholes. it can. Here, by forming a zinc chromate treatment layer as a chromate treatment layer, the resistance when forming an ultrathin copper foil by electroplating is lower than that of a normal chromate treatment layer, and the generation of pinholes is further suppressed. be able to.

  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 treatment layer is thinly present at the interface of the ultrathin copper layer, while the ultrathin copper layer does not peel off from the carrier before the laminating process on the insulating substrate, while after the laminating process on the insulating substrate It is preferable for obtaining the property that the ultrathin copper layer can be peeled from the carrier. If a chromate treatment layer is present at the boundary between the carrier and the ultrathin copper layer without providing a nickel layer or an alloy layer containing nickel (for example, a nickel-zinc alloy layer), the peelability is hardly improved and the chromate treatment layer If the nickel layer or nickel-containing alloy layer (for example, nickel-zinc alloy layer) and the ultrathin copper layer are directly laminated, the nickel amount in the nickel layer or nickel-containing alloy layer (for example, nickel-zinc alloy layer) Accordingly, the peel strength is too strong or too weak to obtain an appropriate peel strength.

  In addition, if the chromate treatment layer is present at the boundary between the carrier and the nickel layer or an alloy layer containing nickel (for example, a nickel-zinc alloy layer), the intermediate layer is also peeled off along with the peeling of the ultrathin copper layer. And the intermediate layer is undesirably peeled off. Such a situation may occur not only when the chromate treatment layer is provided at the interface with the carrier, but also when the amount of chromium is excessive even if the chromate treatment 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.

Intermediate nickel layer or nickel-containing alloy layer (eg nickel-zinc alloy layer) is formed by wet plating such as electroplating, electroless plating and immersion plating, or dry plating such as sputtering, CVD and PDV can do. Electroplating is preferable from the viewpoint of cost. When the carrier is a resin film, the intermediate layer can be formed by dry plating such as CVD and PDV or wet plating such as electroless plating and immersion plating.
In addition, the chromate treatment layer can be formed with, for example, electrolytic chromate or immersion chromate, but the chromium concentration can be increased, and the peel strength of the ultra-thin copper layer from the carrier is improved. Preferably formed.
Further, the amount of adhered 100~40000μg / dm ² of nickel in the intermediate layer, the adhesion amount of chromium 5~100μg / dm ^2, the amount of deposition of zinc is preferably 1~70μg / dm ^2. Moreover, it is preferable when the Ni adhesion amount on the surface of the ultrathin copper layer on the carrier side after peeling the ultrathin copper layer from the carrier is 5 to 300 μg / dm ² because the etching property of the ultrathin copper layer is improved. In order to control the amount of Ni on the surface of the ultrathin copper layer after peeling the carrier, a metal species (Cr that suppresses the diffusion of Ni to the ultrathin copper layer side while reducing the Ni adhesion amount of the intermediate layer) , Zn) is preferably contained in the intermediate layer. From this point of view, Ni content of the intermediate layer is preferably from 100~40000μg / dm ^2, more preferably not less 200 [mu] g / dm ² or more 20000μg / dm ² or less, 500 [mu] g / dm ² or more 10000 / more preferably at dm ² or less, and even more preferably 700 [mu] g / dm ² or more 5000 [mu] g / dm ² or less. Further, Cr is preferably contained 5~100μg / dm ^2, more preferably not less 8 [mu] g / dm ² or more 50 [mu] g / dm ² or less, more preferably at 10 [mu] g / dm ² or more 40 [mu] g / dm ² or less, More preferably, it is 12 μg / dm ² or more and 30 μg / dm ² or less. Zn is preferably contained 1~70μg / dm ^2, more preferably not less 3 [mu] g / dm ² or more 30 [mu] g / dm ² or less, and even more preferably 5 [mu] g / dm ² or more 20 [mu] g / dm ² or less.

<Ni adhesion amount on ultrathin copper layer surface>
The amount of Ni deposited on the surface of the ultrathin copper layer can be measured as follows.
The copper foil with a carrier was bonded to a BT resin (triazine-bismaleimide resin, manufactured by Mitsubishi Gas Chemical Co., Ltd.) on the ultrathin copper layer side and thermocompression bonded at 220 ° C. for 2 hours. Thereafter, the ultrathin copper layer was peeled off from the copper foil carrier in accordance with JIS C 6471 (Method A). Subsequently, the adhesion amount of Ni on the surface on the intermediate layer side of the ultrathin copper layer was measured by dissolving the sample with nitric acid having a concentration of 20% by mass and performing ICP emission analysis. In addition, when the surface treatment containing Ni is performed on the surface opposite to the surface on the intermediate layer side of the ultrathin copper layer, only the vicinity of the surface on the intermediate layer side of the ultrathin copper layer is dissolved (from the surface). It is possible to measure the adhesion amount of Ni on the surface of the ultrathin copper layer on the intermediate layer side by dissolving only 0.5 μm thickness or 10% of the thickness of the ultrathin copper layer.

<Metal adhesion amount of intermediate layer>
The metal adhesion amount of the intermediate layer can be measured as follows.
The amount of nickel deposited was measured by ICP emission analysis after dissolving the sample in nitric acid at a concentration of 20% by mass. The amount of zinc, chromium and molybdenum deposited was dissolved in hydrochloric acid at a concentration of 7% by mass and determined by atomic absorption spectrometry. It was measured by performing an analysis. In addition, the measurement of the said nickel, zinc, chromium, and molybdenum adhesion amount was performed as follows. First, after peeling an ultrathin copper layer from a copper foil with a carrier, only the vicinity of the surface on the intermediate layer side of the ultrathin copper layer is dissolved (only 0.5 μm thickness from the surface or 10 of the thickness of the ultrathin copper layer). %), And measure the amount of adhesion on the surface of the intermediate layer side of the ultrathin copper layer. Further, after peeling off the ultrathin copper layer, only the vicinity of the surface on the intermediate layer side of the carrier is dissolved (only the thickness of 0.5 μm from the surface is dissolved), and the amount of adhesion on the surface of the carrier on the intermediate layer side is measured. And the value which totaled the adhesion amount of the surface by the side of the intermediate | middle layer of an ultra-thin copper layer and the adhesion amount of the surface by the side of the intermediate | middle layer of a carrier was made into the metal adhesion amount of an intermediate | middle layer.

The intermediate layer of the carrier-attached copper foil of the present invention is laminated in the order of a nickel layer or an alloy layer containing nickel, and an organic material layer containing any of a nitrogen-containing organic compound, a sulfur-containing organic compound and a carboxylic acid on the carrier. The adhesion amount of nickel in the intermediate layer may be 100 to 40,000 μg / dm ² . The alloy containing nickel is an alloy composed of nickel and one or more elements selected from the group consisting of cobalt, iron, chromium, molybdenum, zinc, tantalum, copper, aluminum, phosphorus, tungsten, tin, arsenic, and titanium. I mean. The alloy containing nickel may be an alloy composed of three or more elements. Moreover, the intermediate layer of the copper foil with a carrier of the present invention is an organic layer containing any one of a nitrogen-containing organic compound, a sulfur-containing organic compound and a carboxylic acid on the carrier, and a nickel layer or an alloy layer containing nickel. It is constituted by being laminated, and the adhesion amount of nickel in the intermediate layer may be 100 to 40,000 μg / dm ² . The alloy containing nickel is an alloy composed of nickel and one or more elements selected from the group consisting of cobalt, iron, chromium, molybdenum, zinc, tantalum, copper, aluminum, phosphorus, tungsten, tin, arsenic, and titanium. I mean. The alloy containing nickel may be an alloy composed of three or more elements. Moreover, it is preferable when the Ni adhesion amount on the surface of the ultrathin copper layer on the carrier side after peeling the ultrathin copper layer from the carrier is 5 to 300 μg / dm ² because the etching property of the ultrathin copper layer is improved. In order to control the amount of Ni on the surface of the ultrathin copper layer after peeling the carrier, the nitrogen-containing organic compound that suppresses the diffusion of Ni to the ultrathin copper layer side while reducing the amount of Ni deposited on the intermediate layer It is preferable that the intermediate layer includes an organic material layer containing any of a sulfur-containing organic compound and a carboxylic acid. From this point of view, Ni content of the intermediate layer is preferably from 100~40000μg / dm ^2, more preferably not less 200 [mu] g / dm ² or more 20000μg / dm ² or less, 300 [mu] g / dm ² or more 10000 / more preferably at dm ² or less, and even more preferably 500 [mu] g / dm ² or more 5000 [mu] g / dm ² or less. Moreover, BTA (benzotriazole), MBT (mercaptobenzothiazole), etc. are mentioned as an organic substance containing either the said nitrogen containing organic compound, sulfur containing organic compound, and carboxylic acid.

Moreover, as an organic substance which an intermediate | middle layer contains, it is preferable to use what consists of 1 type, or 2 or more types selected from a nitrogen containing organic compound, a sulfur containing organic compound, and carboxylic acid. Among the nitrogen-containing organic compound, the sulfur-containing organic compound, and the carboxylic acid, the nitrogen-containing organic compound includes a nitrogen-containing organic compound having a substituent. Specific nitrogen-containing organic compounds include 1,2,3-benzotriazole, carboxybenzotriazole, N ′, N′-bis (benzotriazolylmethyl) urea, 1H-1 which are triazole compounds having a substituent. 2,4-triazole, 3-amino-1H-1,2,4-triazole and the like are preferably used.
For the sulfur-containing organic compound, it is preferable to use mercaptobenzothiazole, 2-mercaptobenzothiazole sodium, thiocyanuric acid, 2-benzimidazolethiol, and the like.
As the carboxylic acid, it is particularly preferable to use a monocarboxylic acid, and it is particularly preferable to use oleic acid, linoleic acid, linolenic acid, or the like.
The organic material is preferably contained in a thickness of 25 nm to 80 nm, more preferably 30 nm to 70 nm. The intermediate layer may contain a plurality of types (one or more) of the aforementioned organic substances.
In addition, the thickness of organic substance can be measured as follows.

<Thickness of organic material in the intermediate layer>
After peeling off the ultrathin copper layer of the carrier-attached copper foil from the carrier, the surface of the exposed ultrathin copper layer on the intermediate layer side and the exposed surface of the intermediate layer side of the carrier are subjected to XPS measurement to create a depth profile. The depth at which the carbon concentration first becomes 3 at% or less from the surface on the intermediate layer side of the ultrathin copper layer is defined as A (nm), and the carbon concentration is initially 3 at% or less from the surface on the intermediate layer side of the carrier. The resulting depth can be defined as B (nm), and the sum of A and B can be defined as the thickness (nm) of the organic substance in the intermediate layer.
XPS operating conditions are shown below.
・ Device: XPS measuring device (ULVAC-PHI, Model 5600MC)
・ Achieving 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 )

  The method for using the organic substance contained in the intermediate layer will be described below with reference to the method for forming the intermediate layer on the carrier foil. The intermediate layer is formed on the carrier by dissolving the above-mentioned organic substance in a solvent and immersing the carrier in the solvent, or showering, spraying method, dropping method and electrodeposition method on the surface on which the intermediate layer is to be formed. Etc., and there is no need to adopt a particularly limited method. At this time, the concentration of the organic agent in the solvent is preferably in the range of a concentration of 0.01 g / L to 30 g / L and a liquid temperature of 20 to 60 ° C. in all the organic substances described above. The concentration of the organic substance is not particularly limited, and there is no problem even if the concentration is originally high or low. In addition, the organic substance thickness of an intermediate | middle layer tends to become large, so that the density | concentration of organic substance is high, and the contact time of the carrier to the solvent which dissolved the organic substance mentioned above is long. And when the organic substance thickness of an intermediate | middle layer is thick, it exists in the tendency for the effect of organic substance to suppress the spreading | diffusion to the ultra-thin copper layer side of Ni to become large. In addition, the intermediate layer is preferably configured by stacking nickel and molybdenum or cobalt or a molybdenum-cobalt alloy in this order on a carrier. Since the adhesion force between nickel and copper is higher than the adhesion force between molybdenum or cobalt and copper, when peeling the ultrathin copper layer, the interface between the ultrathin copper layer and molybdenum or cobalt or molybdenum-cobalt alloy It will come off. 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.

  The aforementioned nickel may be an alloy containing nickel. Here, the alloy containing nickel is composed of nickel and one or more elements selected from the group consisting of cobalt, iron, chromium, molybdenum, zinc, tantalum, copper, aluminum, phosphorus, tungsten, tin, arsenic, and titanium. An alloy. The molybdenum described above may be an alloy containing molybdenum. Here, the alloy containing molybdenum is composed of molybdenum and one or more elements selected from the group consisting of cobalt, iron, chromium, nickel, zinc, tantalum, copper, aluminum, phosphorus, tungsten, tin, arsenic, and titanium. An alloy. The cobalt described above may be an alloy containing cobalt. Here, the alloy containing cobalt is made of cobalt and one or more elements selected from the group consisting of molybdenum, iron, chromium, nickel, zinc, tantalum, copper, aluminum, phosphorus, tungsten, tin, arsenic, and titanium. An alloy.

Molybdenum-cobalt alloy is an element other than molybdenum and cobalt (for example, one or more elements selected from the group consisting of cobalt, iron, chromium, molybdenum, zinc, tantalum, copper, aluminum, phosphorus, tungsten, tin, arsenic, and titanium). May be included.
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 molybdenum or cobalt or molybdenum-cobalt alloy layer is thinly present at the interface of the ultrathin copper layer, while the ultrathin copper layer does not peel off from the carrier before the lamination process to the insulating substrate, while the insulating substrate It is preferable for obtaining the property that the ultrathin copper layer can be peeled off from the carrier after the lamination step. If a molybdenum or cobalt or molybdenum-cobalt alloy layer is present at the boundary between the carrier and the ultrathin copper layer without providing a nickel layer, the peelability may be hardly improved, and the molybdenum or cobalt or molybdenum-cobalt alloy layer When the nickel layer and the ultrathin copper layer are directly laminated, the peel strength may be too strong or too weak depending on the amount of nickel in the nickel layer, and an appropriate peel strength may not be obtained.

  In addition, if the molybdenum or cobalt or molybdenum-cobalt alloy layer is present at the boundary between the carrier and the nickel layer, the intermediate layer may be additionally peeled off when the ultrathin copper layer is peeled off, that is, between the carrier and the intermediate layer. May cause undesirable peeling. Such a situation is not only when a molybdenum or cobalt or molybdenum-cobalt alloy layer is provided at the interface with the carrier, but also when a molybdenum or cobalt or molybdenum-cobalt alloy layer is provided at the interface with the ultrathin copper layer. This can occur if the amount of molybdenum or cobalt is too high. 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 it is difficult to peel off, while molybdenum or cobalt and copper are less likely to dissolve and mutual diffusion. This is considered to be because the adhesive force is weak at the interface between the molybdenum or cobalt or molybdenum-cobalt alloy layer and copper and is easily peeled off. Further, when the amount of nickel in the intermediate layer is insufficient, since only a small amount of molybdenum or cobalt is present between the carrier and the ultrathin copper layer, they may be in close contact and difficult to peel off.

  The intermediate layer nickel and cobalt or molybdenum-cobalt alloy can be formed by wet plating such as electroplating, electroless plating and immersion plating, or dry plating such as sputtering, CVD and PDV. Molybdenum can be formed only by dry plating such as CVD and PDV. Electroplating is preferable from the viewpoint of cost.

In the intermediate layer, the adhesion amount of nickel is preferably 100 to 40000 μg / dm ² , the adhesion amount of molybdenum is 10 to 1000 μg / dm ² , and the adhesion amount of cobalt is preferably 10 to 1000 μg / dm ² . Moreover, it is preferable when the Ni adhesion amount on the surface of the ultrathin copper layer on the carrier side after peeling the ultrathin copper layer from the carrier is 5 to 300 μg / dm ² because the etching property of the ultrathin copper layer is improved. In order to control the amount of Ni on the surface of the ultrathin copper layer after peeling off the carrier, the amount of Ni deposited on the intermediate layer is reduced and the metal species (Co) that suppresses the diffusion of Ni to the ultrathin copper layer side is reduced. , Mo) is preferably contained in the intermediate layer. From this viewpoint, the amount of nickel deposited is preferably to 100~40000μg / dm ^2, preferably to 200~20000μg / dm ^2, more preferably to 300~15000μg / dm ^2, 300~10000μg / Dm ² is more preferable. If included molybdenum in the intermediate layer, a molybdenum deposition amount is preferably set to 10~1000μg / dm ^2, the molybdenum deposition amount is preferably set to 20~600μg / dm ^2, and 30~400μg / dm ² More preferably. If included cobalt in the intermediate layer, the cobalt coating weight is preferably set to 10~1000μg / dm ^2, cobalt deposition amount is preferably set to 20~600μg / dm ^2, and 30~400μg / dm ² More preferably.

  As described above, the intermediate layer is plated for providing a molybdenum, cobalt, or molybdenum-cobalt alloy layer when nickel and molybdenum, cobalt, or a molybdenum-cobalt alloy are stacked in this order on a carrier. When the current density in the treatment is lowered and the carrier conveyance speed is lowered, the density of the molybdenum, cobalt, or molybdenum-cobalt alloy layer tends to increase. When the density of the layer containing molybdenum and / or cobalt increases, nickel in the nickel layer becomes difficult to diffuse, and the amount of Ni on the surface of the ultrathin copper layer after peeling can be controlled.

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

<Ultrathin copper layer>
An ultrathin copper layer is provided on the release 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. It is typically 0.5-12 μm, more typically 2-5 μm.

<Roughening treatment>
Usually, the surface of the copper foil of the copper foil with a carrier is used for the purpose of improving the peel strength of the ultrathin copper layer after lamination on the surface to be bonded to the resin substrate, that is, the roughened surface. In addition, a roughening treatment for performing “fist-knot” -shaped electrodeposition is performed. In the present invention, including such pretreatment and finishing treatment, a known treatment related to copper foil roughening is included as necessary, and is referred to as “roughening treatment”.

  When this roughening treatment is performed by a plating treatment such as plating containing a copper-cobalt-nickel alloy (in the following description, in order to clarify the difference between the roughening treatment of the plating and the previous step, “ Secondary particle layer "), simply by forming a plating layer such as a plating layer containing a copper-cobalt-nickel alloy on the copper foil, as described above, the shape of the roughened particles becomes dendritic. Therefore, problems such as “powder falling” that peels off from the upper part or root of this tree branch occur.

The microscope picture of the surface of the copper foil which formed the plating layer containing a copper-cobalt-nickel alloy on copper foil is shown in FIG. As shown in FIG. 3, fine particles developed in a dendritic shape can be seen. In general, the fine particles developed in a dendritic shape shown in FIG. 3 are produced at a high current density.
When processed at such a high current density, particle nucleation during initial electrodeposition is suppressed, and new particle nuclei are formed at the tip of the particle. Will grow.
Therefore, to prevent this, when electroplating is performed at a reduced current density, there is no sharp rise, the number of particles increases, and rounded particles grow. Even under such circumstances, powder falling is slightly improved, but sufficient peel strength cannot be obtained, which is not sufficient for achieving the object of the present invention.

  The state of powder falling when a plating layer containing a copper-cobalt-nickel alloy as shown in FIG. 3 is formed is shown in the conceptual explanatory diagram of FIG. The cause of this powder fall is that fine particles are formed in a dendritic shape on the copper foil as described above. However, the dendritic particles are easily broken by an external force and fall off from the root. The fine dendritic particles cause peeling due to “rubbing” during the process, contamination of the roll with peeling powder, and etching residue due to peeling powder.

In this invention, after forming a primary particle layer in advance on the surface of an ultrathin copper layer, a secondary particle layer is formed on the primary particle layer. FIG. 4 shows a photomicrograph of the surface on which the primary particles and secondary particles are formed on the ultrathin copper layer.
This eliminates peeling due to “rubbing” during processing, dirt on the roll due to peeling powder, etching residue due to peeling powder, suppressing occurrence of powder falling, and improving the peel strength of the copper foil with carrier. Can be obtained.

The optimum condition for preventing powder falling is to set the average particle size of the primary particle layer to 0.10 to 0.45 μm and the average particle size of the secondary particle layer to 0.35 μm or less.
The lower limit of the average particle diameter of the primary particle layer is preferably 0.27 μm or more, preferably 0.29 μm or more, more preferably 0.30 μm or more, more preferably 0.33 μm or more. The upper limit of the average particle diameter of the primary particle layer is preferably 0.44 μm or less, preferably 0.43 μm or less, preferably 0.40 μm or less, preferably 0.39 μm or less. The upper limit of the average particle size of the secondary particle layer is preferably 0.34 μm or less, preferably 0.33 μm or less, preferably 0.32 μm or less, preferably 0.31 μm or less, preferably 0.30 μm or less, preferably Is 0.28 μm or less, preferably 0.27 μm or less. Further, the lower limit of the average particle diameter of the secondary particle layer is not particularly limited. For example, 0.001 μm or more, or 0.01 μm or more, or 0.05 μm or more, or 0.09 μm or more, or 0.10 μm or more. Or 0.12 μm or more, or 0.15 μm or more.

The primary particle layer and the secondary particle layer are formed by an electroplating layer. The secondary particles are characterized by one or more dendritic particles grown on the primary particles. Or normal plating grown on the primary particles. That is, in the present specification, when the term “secondary particle layer” is used, a normal plating layer such as overlay plating is also included. Further, the secondary particle layer may be a layer having one or more layers formed of roughened particles, or may be a layer having one or more normal plating layers, and is normal with a layer formed of roughened particles. A layer having one or more plating layers may be used.
The peel strength of the primary particle layer and the secondary particle layer thus formed can be 0.80 kg / cm or more, and further, the adhesive strength can be 0.90 kg / cm or more.

In the copper foil with carrier in which the primary particle layer and the secondary particle layer are formed on an ultrathin copper layer, more importantly, the ratio of the three-dimensional surface area to the two-dimensional surface area measured using a laser microscope on the roughened surface Is 1.9 or more and less than 2.2.
Regarding the restriction and adjustment of the surface area ratio, the roughened surface of the ultrathin copper layer is formed from a particle layer that is an aggregate of individual roughened particles, and the particle layer is more macroscopic than particle growth control. By controlling in such a range, there is no fluctuation, that is, an effect of improving the stable peel strength and preventing a stable powder falling phenomenon. Further, even if the size of each roughened particle is controlled, if fine roughened particles are stacked in the height direction, powder falling occurs. Therefore, it is important to limit and adjust the surface area ratio that provides a three-dimensional roughened particle structure.

When the surface area ratio is less than 2.0, the peel strength is insufficient. As a result of measuring the three-dimensional surface roughness of the standard rolled copper foil before roughening using a laser microscope, it was 20043 μm ² and the ratio of the three-dimensional surface area to the two-dimensional surface area was 2.02. Therefore, it can be said that 2.03 or more is desirable for securing the peel strength. Moreover, since it will become easy to generate | occur | produce a powder fall phenomenon when it exceeds 2.2, it can be said that it is desirable to set it as said range.
The upper limit of the surface area ratio (three-dimensional surface area ratio to two-dimensional surface area) is preferably 2.19 or less, preferably 2.17 or less, preferably 2.15 or less. The lower limit of the surface area ratio (three-dimensional surface area ratio to two-dimensional surface area) is preferably 2.04 or more, preferably 2.05 or more, and preferably 2.06 or more.
The measurement method using a laser microscope is to measure a three-dimensional surface area in a range equivalent to 100 × 100 μm of the roughened surface using a laser microscope VK8500 manufactured by Keyence Corporation, and in the actual data range of 9944.4 μm ² . ÷ Set by the method of 2D surface area = surface area ratio.

  The primary particle layer may include copper. Further, the secondary particle layer contains one or more selected from the group consisting of nickel and cobalt, and may contain copper. Moreover, a secondary particle layer may contain copper, cobalt, and nickel, and may contain the alloy which consists of copper, cobalt, and nickel. When copper is contained in the primary particle layer and the secondary particle layer, the primary particle layer is easily removed by etching at the time of circuit formation, so that there is an advantage that productivity in producing a printed wiring board is improved. . In addition, when cobalt or nickel is contained in the secondary particle layer, there is an advantage that the peel strength between the heated resin and the ultrathin copper layer is hardly deteriorated.

(Plating conditions for forming primary particles)
An example of the primary particle plating conditions is as follows.
In addition, this plating condition shows a suitable example to the last, and a primary particle bears the role which prevents the powder fall produced by the particle | grains formed on copper foil with a carrier falling off. Therefore, as long as the average particle diameter falls within the range of the present invention, the plating conditions other than those indicated below are not disturbed. The present invention includes these.
In addition, the average particle diameter of primary particles can be controlled by controlling the current density and the coulomb amount as described below. Further, the surface area ratio can be controlled.
In addition to the following copper plating baths, plating baths for forming primary particles include silver plating baths, gold plating baths, nickel plating baths, cobalt plating baths, zinc plating baths, nickel zinc alloy plating baths, etc. These known plating baths can be used.
Various additives (metal ions, inorganic substances, organic substances) may be added to the plating solution.
Liquid composition: Copper 10-20 g / L, sulfuric acid 50-100 g / L
Liquid temperature: 25-50 degreeC
<First stage>
Current density: 40 to 65 A / dm ²
Coulomb amount: 30-80 As / dm ²
<Second stage>
Current density: 1 to 20 A / dm ²
Coulomb amount: 2-30 As / dm ²

(Cover plating conditions)
Various additives (metal ions, inorganic substances, organic substances) may be added to the plating solution.
Liquid composition: Copper 10-20 g / L, sulfuric acid 50-100 g / L
Liquid temperature: 25-35 degreeC
Current density: 15-20 A / dm ²
Coulomb amount: 30-60 As / dm ²

(Plating conditions for forming secondary particles)
As described above, this plating condition is merely a suitable example, the secondary particles are formed on the primary particles, and the average particle diameter plays a role in preventing powder falling. is there. Therefore, as long as the average particle diameter falls within the range of the present invention, the plating conditions other than those indicated below are not disturbed. The present invention includes these.
In addition, the average particle diameter of the secondary particles can be controlled by controlling the current density and the amount of coulomb as described below. Further, the surface area ratio can be controlled.
The plating bath for forming secondary particles is not limited to the following alloy plating baths of copper and other elements, but also alloy plating baths of silver and other elements, alloys of gold and other elements. Examples include plating baths, alloy plating baths of nickel and other elements, alloy plating baths of cobalt and other elements, alloy plating baths of zinc and other elements, nickel zinc alloy plating baths, and the like. The plating bath can be used.
Various additives (metal ions, inorganic substances, organic substances) may be added to the plating solution.
Liquid composition: Copper 10-20 g / L, nickel 5-15 g / L or / and cobalt 5-15 g / L
pH: 2-3
Liquid temperature: 30-50 degreeC
Current density: 20-30 A / dm ²
Coulomb amount: 10-30 As / dm ²

(Plating conditions for forming the heat-resistant layer 1)
In the present invention, a heat-resistant layer can be further formed on the secondary particle layer. The plating conditions are shown below.
Liquid composition: Nickel 5-20 g / L, cobalt 1-8 g / L
pH: 2-3
Liquid temperature: 40-60 degreeC
Current density: 5 to 20 A / dm ²
Coulomb amount: 10-20 As / dm ²

(Plating conditions for forming the heat-resistant layer 2)
In the present invention, the following heat-resistant layer can be further formed on the secondary particle layer. The plating conditions are shown below.
Liquid composition: nickel 2-30 g / L, zinc 2-30 g / L
pH: 3-4
Liquid temperature: 30-50 degreeC
Current density: 1 to ^{2 A} / dm ²
Coulomb amount: 1-2 As / dm ²

(Plating conditions for forming a rust prevention layer)
The present invention can further form the following antirust layer. The plating conditions are shown below. In the following, conditions for the immersion chromate treatment are shown, but electrolytic chromate treatment may be used.
Liquid composition: potassium dichromate 1-10 g / L, zinc 0-5 g / L
pH: 3-4
Liquid temperature: 50-60 degreeC
Current density: 0 to ^{2 A} / dm ² (for immersion chromate treatment)
Coulomb amount: 0 to ^{2 As} / dm ² (for immersion chromate treatment)

(Type of weather-resistant layer)
As an example, application of a diaminosilane aqueous solution can be mentioned.

The copper-cobalt-nickel alloy plating as the secondary particles is a ternary alloy of 10-30 mg / dm ² copper-100-3000 μg / dm ² cobalt-50-500 μg / dm ² nickel by electrolytic plating. A layer can be formed.
When the Co adhesion amount is less than 100 μg / dm ² , the heat resistance is deteriorated and the etching property is also deteriorated. If the amount of Co adhesion exceeds 3000 μg / dm ² , it is not preferable when the influence of magnetism must be taken into account, etching spots occur, and deterioration of acid resistance and chemical resistance can be considered.

When the Ni adhesion amount is less than 50 μg / dm ² , the heat resistance deteriorates. On the other hand, when the Ni adhesion amount exceeds 500 μg / dm ² , the etching property is lowered. That is, although it is not at a level where etching remains and etching cannot be performed, it becomes difficult to form a fine pattern. Preferred Co deposition amount is 500~2000μg / dm ^2, and preferably nickel coating weight is 50~300μg / dm ^2.
From the above, it can be said that the adhesion amount of the copper-cobalt-nickel alloy plating is desirably 10 to 30 mg / dm ² copper-100 to 3000 μg / dm ² cobalt-50 to 500 μg / dm ² nickel. Each adhesion amount of the ternary alloy layer is a desirable condition, and a range exceeding this amount is not denied.

Here, the etching stain means that Co remains without being dissolved when etched with copper chloride, and the etching residue means that Ni remains undissolved when alkaline etching is performed with ammonium chloride. It means to end.
In general, when a circuit is formed, an alkaline etching solution and a copper chloride based etching solution as described in the following examples are used. Although this etching solution and etching conditions are versatile, it should be understood that they are not limited to these conditions and can be arbitrarily selected.

In the present invention, as described above, after the secondary particles are formed (after the roughening treatment), a cobalt-nickel alloy plating layer can be formed on the roughened surface.
The cobalt-nickel alloy plating layer preferably has a cobalt adhesion amount of 200 to 3000 μg / dm ² and a cobalt ratio of 60 to 66 mass%. This treatment can be regarded as a kind of rust prevention treatment in a broad sense.
This cobalt-nickel alloy plating layer needs to be performed to such an extent that the peel strength between the copper foil and the substrate is not substantially lowered. A cobalt adhesion amount of less than 200 μg / dm ² is not preferable because the heat-resistant peel strength is lowered, the oxidation resistance and chemical resistance are deteriorated, and the treated surface becomes reddish.
On the other hand, when the cobalt adhesion amount exceeds 3000 μg / dm ² , it is not preferable when the influence of magnetism must be taken into consideration, etching spots occur, and deterioration of acid resistance and chemical resistance is considered. A preferable cobalt adhesion amount is 400 to 2500 μg / dm ² .

Moreover, when there is much cobalt adhesion amount, it may become a cause of generation | occurrence | production of a soft etching penetration. From this, it can be said that the ratio of cobalt is preferably 60 to 66 mass%.
As will be described later, the direct cause of soft etching soaking is a heat-resistant rust-preventing layer consisting of a zinc-nickel alloy plating layer, but cobalt may also cause stains during soft etching. The above adjustment is a more desirable condition.
On the other hand, when the nickel adhesion amount is small, the heat-resistant peel strength is lowered, and the oxidation resistance and chemical resistance are lowered. Further, when the nickel adhesion amount is too large, the alkali etching property is deteriorated, so it is desirable to determine the balance with the cobalt content.

In the present invention, a zinc-nickel alloy plating layer can be further formed on the cobalt-nickel alloy plating. The total amount of the zinc-nickel alloy plating layer is 150 to 500 μg / dm ² , and the nickel ratio is 16 to 40% by mass. This has a role of a heat-resistant rust-proof layer. This condition is also a preferable condition, and other known zinc-nickel alloy plating can be used. It will be understood that this zinc-nickel alloy plating is a preferred additional condition in the present invention.

Further, in the conventional technology, in a minute circuit provided with a zinc-nickel alloy plating layer in a two-layer material in which an ultra-thin copper layer is bonded to a resin by thermocompression bonding, the edge portion of the circuit is infiltrated during soft etching. Discoloration occurs. Nickel has an effect of suppressing penetration of an etching agent (etching aqueous solution of H ₂ SO ₄ : 10 wt%, H ₂ O ₂ : 2 wt%) used in soft etching.
As described above, the total amount of the zinc-nickel alloy plating layer is 150 to 500 μg / dm ² , the lower limit of the nickel ratio in the alloy layer is 16% by mass, the upper limit is 40% by mass, and nickel A content of 50 μg / dm ² or more serves as a heat-resistant rust-preventing layer and suppresses the penetration of the etchant used during soft etching to prevent weakening of the circuit joint strength due to corrosion. It has the effect that it can be done.

In addition, when the total amount of the zinc-nickel alloy plating layer is less than 150 μg / dm ² , the heat resistance and rust prevention ability is lowered and it becomes difficult to play a role as a heat resistance rust prevention layer, and when the total amount exceeds 500 μg / dm ² The hydrochloric acid resistance tends to deteriorate.
Moreover, if the lower limit of the nickel ratio in the alloy layer is less than 16% by mass, the amount of penetration at the time of soft etching exceeds 9 μm, which is not preferable. The upper limit of 40% by mass of the nickel ratio is a technical limit value at which a zinc-nickel alloy plating layer can be formed.

As described above, the present invention sequentially forms a cobalt-nickel alloy plating layer and further a zinc-nickel alloy plating layer as necessary on a plating layer containing a copper-cobalt-nickel alloy as a secondary particle layer. be able to. The total amount of cobalt and nickel deposited in these layers can also be adjusted. It is desirable that the total deposition amount of cobalt is 300 to 4000 μg / dm ² and the total deposition amount of nickel is 150 to 1500 μg / dm ² .
When the total deposition amount of cobalt is less than 300 μg / dm ² , the heat resistance and chemical resistance are lowered, and when the total deposition amount of cobalt exceeds 4000 μg / dm ² , etching spots may occur. Moreover, if the total adhesion amount of nickel is less than 150 μg / dm ² , heat resistance and chemical resistance are lowered. When the total adhesion amount of nickel exceeds 1500 μg / dm ² , an etching residue is generated.
Preferably, the total adhesion amount of the cobalt is 1500~3500μg / dm ^2, and the total deposition amount of nickel is 500~1000μg / dm ^2. If the above conditions are satisfied, the conditions described in this paragraph need not be particularly limited.

Thereafter, a rust prevention treatment is performed as necessary. In the present invention, a preferable antirust treatment is a coating treatment of chromium oxide alone or a mixture coating treatment of chromium oxide and zinc / zinc oxide. Chromium oxide and zinc / zinc oxide mixture coating treatment is zinc or zinc comprising zinc oxide and chromium oxide by electroplating using a plating bath containing zinc salt or zinc oxide and chromate. It is the process which coat | covers the antirust layer of a chromium group mixture.
As the plating bath, typically, at least one kind of dichromate such as K ₂ Cr ₂ O ₇ and Na ₂ Cr ₂ O ₇ and CrO ₃ and a water-soluble zinc salt such as ZnO 2, ZnSO ₄ · 7H are used. A mixed aqueous solution of at least one kind of ₂ O and an alkali hydroxide is used. A typical plating bath composition and electrolysis conditions are as follows.

The copper foil thus obtained has excellent heat resistance peel strength, oxidation resistance and hydrochloric acid resistance. In addition, a circuit having a pitch of 150 μm or less can be etched with the CuCl ₂ etching solution, and alkali etching can be performed. In addition, penetration into the circuit edge portion during soft etching can be suppressed.
As the soft etching solution, an aqueous solution of H ₂ SO ₄ : 10 wt% and H ₂ O ₂ : 2 wt% can be used. Processing time and temperature can be adjusted arbitrarily.
As the alkaline etching solution, for example, NH ₄ OH: 6 mol / liter, NH ₄ Cl: 5 mol / liter, CuCl ₂ : 2 mol / liter (temperature: 50 ° C.) and the like are known.

The copper foil obtained in all the above steps has a black to gray color. Black to gray is significant in terms of alignment accuracy and high heat absorption rate. For example, circuit boards including rigid boards and flexible boards are mounted with components such as ICs, resistors and capacitors in an automatic process, and chip mounting is performed while reading circuits with sensors. At this time, alignment on the copper foil treated surface may be performed through a film such as Kapton. This also applies to positioning when forming a through hole.
The closer the processing surface is to black, the better the light absorption and the higher the positioning accuracy. Furthermore, when producing a substrate, the copper foil and the film are often cured and bonded together while applying heat. At this time, when heating is performed using long waves such as far infrared rays and infrared rays, the heating efficiency is improved when the color tone of the treated surface is black.

Finally, if necessary, silane treatment for applying a silane coupling agent to at least the roughened surface on the rust preventive layer is performed mainly for the purpose of improving the adhesion between the ultrathin copper layer and the resin substrate.
Examples of the silane coupling agent used for the silane treatment include olefin silane, epoxy silane, acrylic silane, amino silane, and mercapto silane, and these can be appropriately selected and used. .
The application method may be any of spraying a silane coupling agent solution by spraying, coating with a coater, dipping, pouring and the like. For example, Japanese Patent Publication No. 60-15654 discloses that the adhesion between an ultrathin copper layer and a resin substrate is improved by subjecting the rough surface side of the ultrathin copper layer to chromate treatment and then silane coupling agent treatment. It is described. Refer to this for details. Thereafter, if necessary, an annealing treatment may be performed for the purpose of improving the ductility of the ultrathin copper layer.
In addition, a heat-resistant layer or a rust-proof layer may be formed on the secondary particle layer with a simple substance or alloy of nickel, cobalt, copper, zinc, etc., and further, a treatment such as chromate treatment or silane coupling treatment is performed on the surface. May be applied. That is, you may form 1 or more types of layers selected from the group which consists of a heat-resistant layer, a rust prevention layer, a chromate process layer, and a silane coupling process layer on the surface of a secondary particle layer. In addition, the above-mentioned heat-resistant layer, rust prevention layer, chromate treatment layer, and silane coupling treatment layer may each be formed of a plurality of layers (for example, 2 layers or more, 3 layers or more, etc.).

<Printed wiring boards, printed circuit boards, and copper-clad laminates>
A copper clad laminate can be produced by attaching a copper foil with a carrier to the insulating resin plate from the ultrathin copper layer side, thermocompression bonding, and peeling the carrier. Thereafter, a copper circuit of a printed wiring board or a printed circuit board can be formed by etching the ultrathin copper layer portion. The insulating resin plate used here is not particularly limited as long as it has characteristics applicable to a printed wiring board or a printed circuit board. For example, a paper base phenolic resin, a paper base epoxy resin for rigid PWB, Use synthetic fiber cloth base epoxy resin, glass cloth / paper composite base epoxy resin, glass cloth / glass non-woven composite base epoxy resin, glass cloth base epoxy resin, etc., polyester film or polyimide film etc. for FPC Can be used. The printed wiring board, printed circuit board, and copper-clad laminate produced in this manner can be mounted on various electronic components that require high-density mounting of the mounted components.

Moreover, the copper foil with a carrier provided with the copper foil carrier and the ultrathin copper layer laminated on the intermediate layer on the copper foil carrier is roughened on the ultrathin copper layer. A layer may be provided, and one or more layers selected from the group consisting of a heat-resistant layer, a rust prevention layer, a chromate treatment layer, and a silane coupling treatment layer may be provided on the roughening treatment layer.
Further, a roughening treatment layer may be provided on the ultrathin copper layer, a heat resistant layer and a rust prevention layer may be provided on the roughening treatment layer, and a chromate treatment is performed on the heat resistance layer and the rust prevention layer. A layer may be provided, and a silane coupling treatment layer may be provided on the chromate treatment layer.
The carrier-attached copper foil includes a resin layer on the ultrathin copper layer, the roughened layer, the heat-resistant layer, the rust-proof layer, the chromate-treated layer, or the silane coupling-treated layer. May be. The resin layer may be an insulating resin layer.

  The resin layer may be an adhesive, or an insulating resin layer in a semi-cured state (B stage state) for bonding. The semi-cured state (B stage state) is a state in which there is no sticky feeling even if the surface is touched with a finger, the insulating resin layer can be stacked and stored, and a curing reaction occurs when subjected to heat treatment. Including that.

  The resin layer may contain a thermosetting resin or may be a thermoplastic resin. The resin layer may include a thermoplastic resin. Although the type is not particularly limited, for example, a resin including an epoxy resin, a polyimide resin, a polyfunctional cyanate ester compound, a maleimide compound, a polyvinyl acetal resin, a urethane resin, or the like can be given as a preferable one. .

  These resins are dissolved in a solvent such as methyl ethyl ketone (MEK) or toluene to obtain a resin liquid, which is applied to the ultrathin copper layer, the heat-resistant layer, the rust-preventing layer, the chromate-treated layer, or the silane cup. On the ring agent layer, for example, it is applied by a roll coater method or the like, and then heat-dried as necessary to remove the solvent to obtain a B-stage state. For example, a hot air drying furnace may be used for drying, and the drying temperature may be 100 to 250 ° C, preferably 130 to 200 ° C.

  The copper foil with a carrier provided with the resin layer (copper foil with a carrier with resin) is superposed on the base material, and the whole is thermocompression bonded to thermally cure the resin layer, and then the carrier is peeled off. Thus, the ultrathin copper layer is exposed (which is naturally the surface on the intermediate layer side of the ultrathin copper layer), and a predetermined wiring pattern is formed thereon.

  If this resin-attached copper foil with a carrier is used, the number of prepreg materials used when manufacturing a multilayer printed wiring board can be reduced. In addition, the copper-clad laminate can be manufactured even if the resin layer is made thick enough to ensure interlayer insulation or no prepreg material is used. At this time, the surface smoothness can be further improved by undercoating the surface of the substrate with an insulating resin.

In addition, when the prepreg material is not used, the material cost of the prepreg material is saved and the laminating process is simplified, which is economically advantageous. Moreover, the multilayer printed wiring board manufactured by the thickness of the prepreg material is used. The thickness is reduced, and there is an advantage that an extremely thin multilayer printed wiring board in which the thickness of one layer is 100 μm or less can be manufactured.
The thickness of the resin layer is preferably 0.1 to 80 μm.

  When the thickness of the resin layer is less than 0.1 μm, the adhesive strength is reduced, and when the copper foil with a carrier with the resin is laminated on the base material provided with the inner layer material without interposing the prepreg material, the circuit of the inner layer material It may be difficult to ensure interlayer insulation between the two.

  On the other hand, if the thickness of the resin layer is greater than 80 μm, it is difficult to form a resin layer having a desired thickness in a single coating process, which is economically disadvantageous because of extra material costs and man-hours. Furthermore, since the formed resin layer is inferior in flexibility, cracks are likely to occur during handling, and excessive resin flow occurs during thermocompression bonding with the inner layer material, making smooth lamination difficult. There is.

  Furthermore, as another product form of this copper foil with a carrier with a resin, on the ultra-thin copper layer, or on the heat-resistant layer, rust-preventing layer, chromate-treated layer, or silane coupling-treated layer After coating with a resin layer and making it into a semi-cured state, the carrier can then be peeled off and manufactured in the form of a copper foil with resin without the carrier.

<Method for manufacturing printed wiring board>
In one embodiment of a method for producing a printed wiring board according to the present invention, a step of preparing a copper foil with a carrier and an insulating substrate according to the present invention, a step of laminating the copper foil with a carrier and an insulating substrate, the carrier After laminating the attached copper foil and the insulating substrate so that the ultrathin copper layer side faces the insulating substrate, a copper-clad laminate is formed through a step of peeling the carrier of the copper foil with carrier, and then a semi-additive method, The method includes a step of forming a circuit by any one of the modified semi-additive method, the partly additive method, and the subtractive method. It is also possible for the insulating substrate to contain an inner layer circuit.

  In the present invention, the semi-additive method refers to a method in which a thin electroless plating is performed on an insulating substrate or a copper foil seed layer, a pattern is formed, and then a conductive pattern is formed using electroplating and etching.

Therefore, in one embodiment of a method for producing a printed wiring board according to the present invention using a semi-additive method, a step of preparing a copper foil with a carrier and an insulating substrate according to the present invention,
Laminating the copper foil with carrier and an insulating substrate;
After laminating the copper foil with carrier and the insulating substrate, the step of peeling the carrier of the copper foil with carrier,
Removing all of the ultrathin copper layer exposed by peeling the carrier by a method such as etching or plasma using a corrosive solution such as acid,
Providing a through hole or / and a blind via in the resin exposed by removing the ultrathin copper layer by etching;
Performing a desmear process on the region including the through hole or / and the blind via,
Providing an electroless plating layer for the region including the resin and the through hole or / and the blind via;
Providing a plating resist on the electroless plating layer;
Exposing the plating resist, and then removing the plating resist in a region where a circuit is formed;
Providing an electrolytic plating layer in a region where the circuit from which the plating resist has been removed is formed;
Removing the plating resist;
Removing the electroless plating layer in a region other than the region where the circuit is formed by flash etching or the like;
including.

In another embodiment of the method for producing a printed wiring board according to the present invention using a semi-additive method, a step of preparing a copper foil with a carrier and an insulating substrate according to the present invention,
Laminating the copper foil with carrier and an insulating substrate;
After laminating the copper foil with carrier and the insulating substrate, the step of peeling the carrier of the copper foil with carrier,
Removing all of the ultrathin copper layer exposed by peeling the carrier by a method such as etching or plasma using a corrosive solution such as acid,
Providing an electroless plating layer on the surface of the resin exposed by removing the ultrathin copper layer by etching;
Providing a plating resist on the electroless plating layer;
Exposing the plating resist, and then removing the plating resist in a region where a circuit is formed;
Providing an electrolytic plating layer in a region where the circuit from which the plating resist has been removed is formed;
Removing the plating resist;
Removing the electroless plating layer and the ultrathin copper layer in a region other than the region where the circuit is formed by flash etching or the like;
including.

  In the present invention, the modified semi-additive method is a method in which a metal foil is laminated on an insulating layer, a non-circuit forming portion is protected by a plating resist, and the copper is thickened in the circuit forming portion by electrolytic plating, and then the resist is removed. Then, a method of forming a circuit on the insulating layer by removing the metal foil other than the circuit forming portion by (flash) etching is indicated.

Therefore, in one embodiment of the method for producing a printed wiring board according to the present invention using the modified semi-additive method, the step of preparing the copper foil with carrier and the insulating substrate according to the present invention,
Laminating the copper foil with carrier and an insulating substrate;
After laminating the copper foil with carrier and the insulating substrate, the step of peeling the carrier of the copper foil with carrier,
Providing a through hole or / and a blind via on the insulating substrate and the ultrathin copper layer exposed by peeling the carrier;
Performing a desmear process on the region including the through hole or / and the blind via,
Providing an electroless plating layer for the region including the through hole or / and the blind via;
Providing a plating resist on the surface of the ultrathin copper layer exposed by peeling the carrier,
Forming a circuit by electrolytic plating after providing the plating resist;
Removing the plating resist;
Removing the ultra-thin copper layer exposed by removing the plating resist by flash etching;
including.

In another embodiment of the method for producing a printed wiring board according to the present invention using the modified semi-additive method, the step of preparing the carrier-attached copper foil and the insulating substrate according to the present invention,
Laminating the copper foil with carrier and an insulating substrate;
After laminating the copper foil with carrier and the insulating substrate, the step of peeling the carrier of the copper foil with carrier,
Providing a plating resist on the exposed ultrathin copper layer by peeling off the carrier;
Exposing the plating resist, and then removing the plating resist in a region where a circuit is formed;
Providing an electrolytic plating layer in a region where the circuit from which the plating resist has been removed is formed;
Removing the plating resist;
Removing the electroless plating layer and the ultrathin copper layer in a region other than the region where the circuit is formed by flash etching or the like;
including.

  In the present invention, the partial additive method means that a catalyst circuit is formed on a substrate provided with a conductor layer, and if necessary, a substrate provided with holes for through holes or via holes, and etched to form a conductor circuit. Then, after providing a solder resist or a plating resist as necessary, it refers to a method of manufacturing a printed wiring board by thickening through holes, via holes, etc. on the conductor circuit by electroless plating.

Therefore, in one embodiment of the method for producing a printed wiring board according to the present invention using a partly additive method, a step of preparing the copper foil with carrier and the insulating substrate according to the present invention,
Laminating the copper foil with carrier and an insulating substrate;
After laminating the copper foil with carrier and the insulating substrate, the step of peeling the carrier of the copper foil with carrier,
Providing a through hole or / and a blind via on the insulating substrate and the ultrathin copper layer exposed by peeling the carrier;
Performing a desmear process on the region including the through hole or / and the blind via,
Applying catalyst nuclei to the region containing the through-holes and / or blind vias;
Providing an etching resist on the surface of the ultrathin copper layer exposed by peeling the carrier,
Exposing the etching resist to form a circuit pattern;
Removing the ultrathin copper layer and the catalyst nucleus by a method such as etching or plasma using a corrosive solution such as an acid to form a circuit;
Removing the etching resist;
A step of providing a solder resist or a plating resist on the surface of the insulating substrate exposed by removing the ultrathin copper layer and the catalyst core by a method such as etching or plasma using a corrosive solution such as an acid;
Providing an electroless plating layer in a region where the solder resist or plating resist is not provided,
including.

  In the present invention, the subtractive method refers to a method of forming a conductor pattern by selectively removing unnecessary portions of a copper foil on a copper clad laminate by etching or the like.

Therefore, in one embodiment of the method for producing a printed wiring board according to the present invention using a subtractive method, a step of preparing the carrier-attached copper foil and the insulating substrate according to the present invention,
Laminating the copper foil with carrier and an insulating substrate;
After laminating the copper foil with carrier and the insulating substrate, the step of peeling the carrier of the copper foil with carrier,
Providing a through hole or / and a blind via on the insulating substrate and the ultrathin copper layer exposed by peeling the carrier;
Performing a desmear process on the region including the through hole or / and the blind via,
Providing an electroless plating layer for the region including the through hole or / and the blind via;
Providing an electroplating layer on the surface of the electroless plating layer;
A step of providing an etching resist on the surface of the electrolytic plating layer or / and the ultrathin copper layer;
Exposing the etching resist to form a circuit pattern;
Removing the ultrathin copper layer and the electroless plating layer and the electrolytic plating layer by a method such as etching or plasma using a corrosive solution such as an acid to form a circuit;
Removing the etching resist;
including.

In another embodiment of the method for producing a printed wiring board according to the present invention using a subtractive method, a step of preparing the carrier-attached copper foil and the insulating substrate according to the present invention,
Laminating the copper foil with carrier and an insulating substrate;
After laminating the copper foil with carrier and the insulating substrate, the step of peeling the carrier of the copper foil with carrier,
Providing a through hole or / and a blind via on the insulating substrate and the ultrathin copper layer exposed by peeling the carrier;
Performing a desmear process on the region including the through hole or / and the blind via,
Providing an electroless plating layer for the region including the through hole or / and the blind via;
Forming a mask on the surface of the electroless plating layer;
Providing an electroplating layer on the surface of the electroless plating layer on which no mask is formed;
A step of providing an etching resist on the surface of the electrolytic plating layer or / and the ultrathin copper layer;
Exposing the etching resist to form a circuit pattern;
Removing the ultra-thin copper layer and the electroless plating layer by a method such as etching or plasma using a corrosive solution such as an acid to form a circuit;
Removing the etching resist;
including.

  The process of providing a through hole or / and a blind via and the subsequent desmear process may not be performed.

Hereinafter, description will be made based on Examples and Comparative Examples. In addition, a present Example is an example to the last, and is not restrict | limited only to this example. That is, other aspects or modifications included in the present invention are included. Example 16 is a reference example.

A long electrolytic copper foil (JTC made by JX Nippon Mining & Metals) having a thickness of 35 μm was prepared as a carrier. A Ni layer having an adhesion amount of 4000 μm / dm ² was formed on the glossy surface (shiny surface) of the copper foil by electroplating on a roll-to-roll continuous plating line under the following conditions.

(Ni layer)
Nickel sulfate: 200-300 g / L
Trisodium citrate: 2 to 10 g / L
pH: 2-4
Bath temperature: 40-70 ° C
Current density: 1-15 A / dm ²

After washing with water and pickling, on the roll-to-roll-type continuous plating line, a Cr layer having an adhesion amount of 11 μg / dm ² was deposited on the Ni layer by electrolytic chromate treatment under the following conditions. .
(Electrolytic chromate treatment)
Liquid composition: potassium dichromate 1-10 g / L, zinc 0-5 g / L
pH: 3-4
Liquid temperature: 50-60 degreeC
Current density: 0.1-2.6 A / dm ²
Coulomb amount: 0.5-30 As / dm ²

Subsequently, on a roll-to-roll type continuous plating line, an ultrathin copper layer having a thickness of 2 to 15 μm was formed on the Cr layer by electroplating under the conditions shown in the following examples and comparative examples. A copper foil with a carrier was produced.
-Ultrathin copper layer Copper concentration: 30-120 g / L
H ₂ SO ₄ concentration: 20 to 120 g / L
Electrolyte temperature: 20-80 ° C
Nika: 1-20ppm
Current density: 10 to 100 A / dm ²

(Examples 1 to 16)
A primary particle layer (Cu) and a secondary particle layer (copper-cobalt-nickel alloy plating, etc.) were formed on the surface of the ultrathin copper layer described above under the conditions shown below.
The used bath composition and plating conditions are as shown in Tables 1 to 3.

  Adjusting the conditions for the formation of the primary particle layer (Cu plating) and the formation of the secondary particle layer (Cu-Co-Ni alloy plating), and the two-dimensional surface area measured using a laser microscope on the roughened surface The ratio of the three-dimensional surface areas was 1.9 or more and less than 2.2. The surface area was measured by the measurement method using the laser microscope.

(Comparative Examples 1-6)
In the comparative example, the bath composition and plating conditions used for forming the roughened layer (primary particle layer and secondary particle layer) on the ultrathin copper layer are as shown in Tables 1 to 3.

When the primary particle layer (Cu plating) and the secondary particle layer (Cu—Co—Ni alloy plating) on the ultrathin copper layer formed by the above example are formed, the average particle size of the primary particles, Table 1 shows the results of measuring the average particle size, powder fall, peel strength, and the ratio of the three-dimensional surface area to the two-dimensional surface area measured using a laser microscope on the roughened surface. The average particle size of the primary particles and secondary particles of the roughened surface was observed with a magnification of 30000 times using S4700 manufactured by Hitachi High-Technologies Corporation, and the average value of the particle sizes was measured. The particle diameter is the diameter of the smallest circle surrounding the particle. And the particle diameter was measured about each 20 primary particles and secondary particles, and the average value was made into the average particle diameter of a primary particle, and the average particle diameter of a secondary particle, respectively. The powder-off characteristics are based on the fact that the tape is discolored due to falling rough particles adhering to the adhesive surface of the tape when a transparent mending tape is applied to the roughened surface of the ultra-thin copper layer. The falling characteristics were evaluated. In other words, when there is no discoloration of the tape ("◎" evaluation in the table), or when it is slight ("○" evaluation in the table), the powder is OK, and the tape turns gray ("×" in the table). Evaluation) was set to powder NG. The normal peel strength is obtained by laminating the ultrathin copper layer roughened surface and the FR4 resin substrate with a hot press to produce a copper clad laminate, and the total thickness of the ultrathin copper layer and the copper plating layer is 15 μm. After providing a copper plating layer on an ultra-thin copper layer, a 10 mm circuit is prepared using a general copper chloride circuit etchant, and the 10 mm circuit is peeled from the substrate, and the normal peel strength is obtained while pulling in the 90 ° direction. It was measured.
Moreover, the same result is shown in Table 1 as a comparative example.
In addition, in the example in which the current condition and two coulomb amounts are described in the primary particle current condition column in Table 1, after performing plating under the conditions described on the left, further plating is performed under the conditions described on the right. Means that For example, in the primary particle current condition column of Example 1, “(65 A / dm ² , 80 As / dm ² ) + (20 A / dm ² , 30 As / dm ² )” is described. After plating with a current density of 65 A / dm ² and a coulomb amount of 80 As / dm ² , plating was further performed with a current density of forming primary particles of 20 A / dm ² and a coulomb amount of 30 As / dm ² . It shows that.

As is apparent from Table 1, the results of the examples of the present invention are as follows.
In Example 1, the current density for forming the primary particles is 65 A / dm ² and 20 A / dm ² , and the coulomb amounts are 80 As / dm ² and 30 As / dm ^2. This is a case where 28 A / dm ² is used and the coulomb amount is 20 As / dm ² .
In addition, although the current density and the amount of Coulomb which form primary particles are two steps, when forming primary particles normally, two steps of electroplating are required. That is, the plating conditions for the first stage core particle formation and the electroplating for the second stage core particle growth.
The first plating conditions are electroplating conditions for forming the first stage nucleating particles, and the second plating conditions are electroplating conditions for growing the second stage nucleating particles. The same applies to the following examples and comparative examples, and the description is omitted.

  Examples 1 to 16 had a primary particle layer and a secondary particle layer, and the value of the ratio of the three-dimensional surface area to the two-dimensional surface area was 1.90 or more and less than 2.20. Was a good value.

On the other hand, the comparative example has the following results.
Comparative Example 1 is a case where secondary particles were not formed after primary particles were formed. As a result, the heat resistance deterioration rate (the peel strength after heating at 180 ° C. for 48 hours after the normal peel measurement was measured and the difference was taken as the deterioration rate) was deteriorated.

  Comparative Example 2 shows a conventional example in which there is no primary particle size and only a secondary particle layer. The ratio of the three-dimensional surface area to the two-dimensional surface area increased, and a large amount of powdered coarse particles occurred.

In Comparative Example 3, the amount of coulomb forming the secondary particles is increased to 73 As / dm ² .
As a result, the ratio of the three-dimensional surface area to the two-dimensional surface area was 2.20, which did not satisfy the conditions of the present invention. A large amount of powder fall occurred.

Comparative Examples 4 and 5 are cases where the current density for forming the secondary particles was increased to 31 A / dm ² and the coulomb amount was increased to 40 As / dm ² .
As a result, the ratio of the three-dimensional surface area to the two-dimensional surface area increased, and a large amount of powder falling occurred.

In Comparative Example 6, the current density of the first stage plating conditions for forming the primary particles is reduced to 40 A / dm ² , the coulomb amount is decreased to 25 As / dm ^2, and the current density for forming the secondary particles is 20 A / dm 2. ^This is a case where the coulomb amount is reduced to ^{2 As} / dm ² .
As a result, the ratio of the three-dimensional surface area to the two-dimensional surface area was reduced, and the peel strength was deteriorated.

Moreover, evaluation about the copper foil with a carrier provided with various intermediate | middle layers was performed as follows.
(Example 17)
A copper layer was formed under the same conditions as in Example 4 except that a Co—Mo alloy was formed as an intermediate layer between the carrier and the copper foil. In this case, the Co—Mo alloy intermediate layer was produced by plating in a plating solution having the following liquid composition.
Liquid composition: CoSO ₄ .7H ₂ O 0.5 to 100 g / L, Na ₂ MoO ₄ .2H ₂ O 0.5 to 100 g / L, sodium citrate dihydrate 20 to 300 g / L
Temperature: 10-70 ° C
pH: 3-5
Current density: 0.1 to 60 A / dm ²

(Example 18)
A copper layer was formed under the same conditions as in Example 4 except that Cr was formed as an intermediate layer between the carrier and the copper foil. In this case, the Cr intermediate layer was produced by plating in a plating solution having the following liquid composition.
Liquid composition: CrO ₃ 200 to 400 g / L, H ₂ SO ₄ 1.5 to ₄ g / L
pH: 1-4
Liquid temperature: 45-60 degreeC
Current density: 10 to 40 A / dm ²

(Example 19)
A copper layer was formed under the same conditions as in Example 4 except that Cr / CuP was formed as an intermediate layer between the carrier and the copper foil. In this case, the Cr / CuP intermediate layer was produced by plating in a plating solution having the following liquid composition.
Liquid composition _{1: CrO 3 200~400g / L,} H 2 SO 4 1.5~4g / L
pH: 1-4
Liquid temperature: 45-60 degreeC
Current density: 10 to 40 A / dm ²
Liquid composition _{2: Cu 2 P 2 O 7} · 3H 2 O 5~50g / L, K 4 P 2 O 7 50~300g / L
Liquid temperature: 30-60 degreeC
pH: 8-10
Current density: 0.1 to 1.0 A / dm ²

(Example 20)
A copper layer was formed under the same conditions as in Example 4 except that Ni / Cr was formed as an intermediate layer between the carrier and the copper foil. In this case, the Ni / Cr intermediate layer was produced by plating in a plating solution having the following liquid composition.
Liquid composition 1: NiSO ₄ · 6H ₂ O 250 to 300 g / L, NiCl ₂ · 6H ₂ O 35 to 45 g / L, boric acid 10 to 50 g / L
Liquid temperature: 30-70 degreeC
pH: 2-6
Current density: 0.1 to 50 A / dm ²
Liquid composition _{2: CrO 3 200~400g / L,} H 2 SO 4 1.5~4g / L
Liquid temperature: 45-60 degreeC
pH: 1-4
Current density: 10 to 40 A / dm ²

(Example 21)
A copper layer was formed under the same conditions as in Example 4 except that a Co / chromate-treated layer was formed as an intermediate layer between the carrier and the copper foil.
In this case, the Co / chromate intermediate layer was produced by plating in a plating solution having the following liquid composition.
Liquid composition _{1: CoSO 4 · 7H 2 O} 10~100g / L, sodium citrate dihydrate 30 to 200 g / L
Liquid temperature: 10-70 degreeC
pH: 3-5
Current density: 0.1 to 60 A / dm ²
Liquid composition 2: CrO ₃ 1-10 g / L
Liquid temperature: 10-70 degreeC
pH: 10-12
Current density: 0.1 to 1.0 A / dm ²

(Example 22)
A copper layer was formed under the same conditions as in Example 4 except that an organic layer was formed as an intermediate layer between the carrier and the copper foil.
In this case, the intermediate layer of the organic layer was prepared by spraying an aqueous carboxybenzotriazole solution having a liquid temperature of 40 ° C., pH 5, and a concentration of 1 to 10 g / L for 10 to 60 seconds.
Test conditions and evaluation results are shown in Table 4.

  In each of Examples 17 to 22, the ratio of the three-dimensional surface area to the two-dimensional surface area was 1.9 or more and less than 2.2, powder falling was suppressed well, and good peel strength was exhibited.

As is clear from the comparison of the above examples and comparative examples, after forming a primary particle layer of copper on the surface of the ultrathin copper layer, a ternary system composed of copper, cobalt and nickel is formed on the primary particle layer. When a secondary particle layer containing an alloy is formed, the ratio of the three-dimensional surface area to the two-dimensional surface area measured using a laser microscope on the roughened surface is 1.9 or more and less than 2.2. It has an excellent effect of being able to stably suppress the phenomenon called powder falling and can further increase the peel strength.
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 containing a ternary alloy composed of copper, cobalt and nickel is 0.30 μm or less. It is more effective in achieving the effect.

Claims (8)

Carrier, intermediate layer, ultrathin copper layer is a copper foil with a carrier laminated in this order,
The ultra-thin copper layer surface has a primary particle layer, and the primary particle layer has a secondary particle layer,
The copper foil with a carrier whose ratio of the three-dimensional surface area with respect to the two-dimensional surface area measured using the laser microscope of the surface in which the said primary particle layer and the secondary particle layer were formed is 2.03 or more and less than 2.2. The copper foil with a carrier according to claim 1 satisfying any one or more of the following (A) to (G).
(A) The average particle diameter of the primary particle layer is 0.10 to 0.45 μm.
(B) The average particle diameter of the secondary particle layer is 0.35 μm or less.
(C) the primary particle layer contains copper,
(D) the secondary particle layer includes one or more selected from the group consisting of nickel and cobalt, and includes copper;
(E) the secondary particle layer contains copper, cobalt and nickel;
(F) the secondary particle layer includes an alloy made of copper, cobalt and nickel,
(G) One or a plurality of dendritic particles grown on the primary particles contained in the primary particle layer, or normal plating grown on the primary particles. Is a layer. The surface side of the ultrathin copper layer having the primary particle layer and the secondary particle layer and the FR4 resin substrate are bonded to each other by hot pressing at 220 ° C. for 2 hours to produce a copper clad laminate, and after the carrier is peeled off, the ultrathin as the thickness of the copper layer and the copper plating layer is 15μm in total, after a copper plating layer provided on the ultra-thin copper layer, to prepare a 10mm circuits using copper chloride circuit etchant, a 10mm circuit the 3. The copper foil with a carrier according to claim 1, wherein the normal peel strength is 0.80 kg / cm or more when the normal peel strength is measured while peeling from the FR4 resin substrate and pulling in a 90 ° direction.   The surface of the said secondary particle layer has 1 or more types of layers selected from the group which consists of a heat-resistant layer, a rust preventive layer, a chromate treatment layer, and a silane coupling treatment layer. Copper foil with carrier.   5. The resin layer is provided on the secondary particle layer or on one or more layers selected from the group consisting of the heat-resistant layer, the rust prevention layer, the chromate treatment layer, and the silane coupling treatment layer. The copper foil with a carrier as described in crab.   The method to manufacture a printed wiring board using the copper foil with a carrier in any one of Claims 1-5.   The method to manufacture a copper clad laminated board using the copper foil with a carrier in any one of Claims 1-5. Preparing a copper foil with a carrier and an insulating substrate according to any one of claims 1 to 5,
Laminating the copper foil with carrier and an insulating substrate;
After laminating the carrier-attached copper foil and the insulating substrate, a copper-clad laminate is formed through a step of peeling the carrier of the carrier-attached copper foil,
Then, the manufacturing method of a printed wiring board including the process of forming a circuit by any method of a semi-additive method, a subtractive method, a partly additive method, or a modified semi-additive method.