TWI619409B - Method for manufacturing surface-treated copper foil, laminated board, printed wiring board, electronic device, copper foil with carrier and printed wiring board - Google Patents

Abstract

Provided is a surface-treated copper foil in which transmission loss is well suppressed even when used for a high-frequency circuit substrate. A surface-treated copper foil having a surface-treated layer formed on at least one surface. The total adhesion amount of Co, Ni, and Fe in the surface-treated layer is 1000 μg / dm ² or less. The surface-treated layer has a Zn metal layer or an alloy-treated layer containing Zn. The ratio of the three-dimensional surface area to the two-dimensional surface area measured by the laser microscope on the surface of the surface treatment layer is 1.0 to 1.9, and the surface roughness Rz JIS of at least one surface is 2.2 μm or less.

Description

Method for manufacturing surface-treated copper foil, laminated board, printed wiring board, electronic device, copper foil with carrier and printed wiring board

The present invention relates to a method for manufacturing a surface-treated copper foil, a laminated board, a printed wiring board, an electronic device, a copper foil with a carrier, and a printed wiring board, and more particularly to a surface-treated copper foil, a laminated board suitable for high-frequency circuit substrate applications Board, printed wiring board, electronic device, copper foil with carrier, and manufacturing method of printed wiring board.

Regarding printed wiring boards, great progress has been made in this half century, and it is now used in almost all electronic devices. As the demand for miniaturization and high performance of electronic devices has increased in recent years, high-density mounting of components and high-frequency signals have been continuously developed, and excellent high-frequency response is required for printed wiring boards.

For high frequency substrates, in order to ensure the quality of the output signal, it is required to reduce the transmission loss. The transmission loss is mainly due to the dielectric loss caused by the resin (substrate side) and the conductor loss caused by the conductor (copper foil side). Regarding the dielectric loss, the smaller the dielectric constant and the dielectric loss tangent of the resin, the smaller the dielectric loss. In high-frequency signals, the main reason for conductor losses is that the higher the frequency becomes, the smaller the cross-sectional area through which the current flows is due to the skin effect of current flowing only on the surface of the conductor, and the higher the resistance becomes.

As a technique for reducing the transmission loss of high-frequency copper foil, for example, Patent Document 1 It is disclosed that a metal foil for high-frequency circuits is coated on one or both sides of the surface of the metal foil with silver or a silver alloy, and the silver or silver alloy coating is provided with a silver or Coatings other than silver alloy. Furthermore, it is described that by this, it is possible to provide a metal foil that can reduce the loss due to the skin effect even in an ultra-high frequency region such as that used in satellite communications.

Further, Patent Document 2 discloses a roughened rolled copper foil for high-frequency circuits, which is characterized in that it is a material for a printed circuit board, and the rolled surface after recrystallization annealing of the rolled copper foil is wound by X-rays. The integrated intensity (I (200)) of the (200) plane obtained by injection is I (200) relative to the integrated intensity (I ₀ (200)) of the (200) plane obtained by X-ray diffraction of fine powder copper. ) / I ₀ (200)> 40, and the arithmetic average roughness (hereinafter, referred to as Ra) of the roughened surface after the roughening treatment using electroplating on the rolled surface is 0.02 μm to 0.2 μm, and the ten-point average roughness is The degree (hereinafter, referred to as Rz) is 0.1 μm to 1.5 μm. In addition, it is described that a printed circuit board that can be used at a high frequency exceeding 1 GHz can be provided.

Furthermore, Patent Document 3 discloses an electrolytic copper foil characterized in that a part of the surface of the copper foil is a concave-convex surface having a surface roughness of 2 to 4 μm which is formed by block-shaped protrusions. Furthermore, it is described that by this, it is possible to provide an electrolytic copper foil excellent in high-frequency transmission characteristics.

[Patent Document 1] Japanese Patent No. 4161304

[Patent Document 2] Japanese Patent No. 4704025

[Patent Document 3] Japanese Patent Laid-Open No. 2004-244656

Conductor loss due to conductor (copper foil side), as described above, due to skin effect The resistance is increased. It is known that the resistance is not only the influence of the resistance of the copper foil itself, but also the resistance of the surface treatment layer formed on the surface of the copper foil by a roughening treatment to ensure adhesion to the resin substrate. Specifically, the roughness of the copper foil surface is the main cause of conductor loss. The smaller the roughness, the lower the transmission loss.

When roughening is performed as the surface treatment of copper foil, it is usually In the case of a Cu-Ni alloy treatment or a Cu-Co-Ni alloy treatment, and a heat-resistant treatment and a rust prevention treatment, a Ni-Zn alloy treatment or a Co-Ni alloy treatment is usually used.

However, it is commonly used in the above-mentioned roughening treatment, heat resistance treatment, and rust prevention treatment. Co, Ni, and Fe are metals exhibiting strong magnetism at room temperature. When they are contained in the surface treatment layer as a component, the following problems arise: the influence of magnetic properties on the current distribution and magnetic field distribution in the conductor will be affected. , The transmission characteristics of copper foil become worse.

An object of the present invention is to provide a transmission loss even in a high-frequency circuit board. The surface treatment copper foil, laminated board, printed wiring board, electronic equipment, copper foil with carrier, and printed wiring board manufacturing method which also has good suppression of power consumption.

The inventors have found that, in order to suppress the influence of ferromagnetic metals on transmission characteristics, By controlling the total adhesion amount of Co, Ni, and Fe in the surface treatment layer of the copper foil to a predetermined amount or less, and containing Zn that does not exhibit strong magnetism at ordinary temperature as a substitute component, high-frequency transmission loss is further reduced. It was further found that, in addition to the previous effect on the surface roughness Rz of the copper foil controlled by high frequency, which significantly affected the transmission loss, the ratio of the three-dimensional surface area to the two-dimensional surface area of the contact area with the resin (dielectric) was more accurately represented It can also have a significant impact on transmission loss.

In one aspect, the present invention completed based on the above findings is a surface-treated copper foil having a surface-treated layer formed on at least one surface thereof. The total adhesion amount of Co, Ni, and Fe in the surface-treated layer is 1000 μg / dm. ² or less, the surface treatment layer a metal layer having a Zn or Zn alloy containing treatment layer of the surface treatment layer surface of a three-dimensional surface area measured using the two-dimensional laser microscope with respect to specific surface area of 1.0 to 1.9, at least one surface of The surface roughness Rz JIS is 2.2 μm or less.

In one embodiment of the surface-treated copper foil of the present invention, the total adhesion amount of Co, Ni, and Fe in the surface-treated layer is 500 μg / dm ² or less.

In another embodiment of the surface-treated copper foil of the present invention, the total adhesion amount of Co, Ni, and Fe in the surface-treated layer is 300 μg / dm ² or less.

In still another embodiment of the surface-treated copper foil of the present invention, the total adhesion amount of Co, Ni, and Fe in the surface-treated layer is 0 μg / dm ² .

In still another embodiment of the surface-treated copper foil of the present invention, the surface roughness Rz JIS of both surfaces is 2.2 μm or less.

In still another embodiment of the surface-treated copper foil of the present invention, the surface-treated layer includes a roughened layer.

In still another embodiment of the surface-treated copper foil of the present invention, the Cu adhesion amount in the roughened layer is 0.10 g / dm ² or less.

In still another embodiment of the surface-treated copper foil of the present invention, in the surface-treated layer, the roughened layer is provided with the Zn metal layer or an alloy-treated layer containing Zn.

In another embodiment, the surface-treated copper foil of the present invention contains Zn The alloy-treated layer is a Cu-Zn alloy layer.

In still another embodiment of the surface-treated copper foil of the present invention, the Zn adhesion amount in the surface-treated layer is 5 mg / dm ² or less.

In still another embodiment of the surface-treated copper foil of the present invention, the surface is In the physical layer, a chromate treatment layer is provided on the Zn metal layer or the Zn-containing alloy treatment layer.

In another embodiment, the surface-treated copper foil of the present invention is A silane coupling treatment layer is provided on the management layer.

In still another embodiment of the surface-treated copper foil of the present invention, the total adhesion amount of Cu, Zn, Co, Ni, and Fe in the surface-treated layer is 0.10 g / dm ² or less.

In another embodiment, the surface-treated copper foil of the present invention is used for flexible printing. Brush the wiring board.

In another embodiment, the surface-treated copper foil of the present invention is used at 5 GHz. The above high frequency circuit board.

In another aspect, the present invention relates to a method of combining the surface-treated copper foil and tree of the present invention. A laminated board prepared by laminating a lipid substrate.

The present invention, in yet another aspect, is a laminated board of the present invention as a material. Printed wiring board.

In still another aspect, the present invention is a printed wiring board using the printed wiring board of the present invention. Electronic machine.

In still another aspect, the present invention is a copper foil with a carrier on one side of the carrier. Or both sides have an intermediate layer and an ultra-thin copper layer in order. The above-mentioned ultra-thin copper layer is the surface-treated copper of the present invention. Foil.

In one embodiment of the copper foil with a carrier of the present invention, the intermediate layer, the ultra-thin copper layer are sequentially provided on one side of the carrier, and the roughened layer is provided on the other side of the carrier.

In still another aspect, the present invention is a laminated board prepared by laminating the copper foil with a carrier and a resin substrate of the present invention.

In yet another aspect, the present invention is a method for manufacturing a printed wiring board, comprising the steps of: preparing the copper foil with a carrier and an insulating substrate of the present invention; and laminating the copper foil with a carrier and the insulating substrate as described above; After the copper foil with a carrier and the insulating substrate are laminated, a metal-clad laminated board is formed through a step of peeling the carrier of the copper foil with a carrier, and then a semi-additive process and a subtractive method ( a step of forming a circuit by any one of a subtractive process, a partially additive process, or a modified semi-additive process.

In yet another aspect, the present invention is a method for manufacturing a printed wiring board, comprising the steps of: forming a circuit on the above-mentioned ultra-thin copper layer side surface or the above-mentioned carrier side surface of the copper foil with a carrier of the present invention; The method of burying the circuit, a step of forming a resin layer on the ultra-thin copper layer side surface of the copper foil with a carrier or the carrier side surface; a step of forming a circuit on the resin layer; and after forming a circuit on the resin layer, Step of peeling the carrier or the ultra-thin copper layer And after the carrier or the ultra-thin copper layer is peeled off, the ultra-thin copper layer or the carrier is removed, so that the circuit formed on the ultra-thin copper layer side surface or the carrier-side surface is buried by the resin layer Exposed steps.

According to the present invention, it is possible to provide a method for manufacturing a surface-treated copper foil, a laminated board, a printed wiring board, an electronic device, a copper foil with a carrier, and a printed wiring board that have a good transmission loss suppression even when used in a high-frequency circuit board.

FIG. 1 is a graph showing the relationship between the total adhesion amount of Co, Ni, and Fe and the surface roughness Rz in Examples and Comparative Examples.

FIG. 2 is a graph showing the relationship between the total adhesion amount of Co, Ni, and Fe and the ratio of the three-dimensional surface area to the two-dimensional surface area in the examples and comparative examples.

FIG. 3 is a graph showing the relationship between the total adhesion amount of Co, Ni, Fe, Cu, and Zn and transmission loss in Examples and Comparative Examples.

(Copper foil substrate)

The form of the copper foil base material that can be used in the present invention is not particularly limited. Typically, it can be used in the form of rolled copper foil or electrolytic copper foil. Generally speaking, electrolytic copper foil is produced by electrolyzing copper from a copper sulfate plating bath onto a titanium or stainless steel drum, and rolled copper foil is produced by repeatedly performing plastic processing and heat treatment using a calender roll. In applications where flexibility is required, rolled copper foil is mostly used.

As the material of the copper foil base material, in addition to high-purity copper such as fine copper or oxygen-free copper, which is usually used as a conductor pattern of printed wiring boards, for example, Sn-doped copper, Ag-doped copper, Cr, Copper alloys such as Zr or Mg, and copper alloys such as corson-based copper alloys to which Ni and Si are added. Furthermore, when the term "copper foil" is used alone in this specification, copper alloy foil is also included. When a copper alloy foil is used as a copper foil for a high-frequency circuit board, the resistivity may not be significantly increased compared to copper.

The thickness of the copper foil substrate is not particularly limited, and is, for example, 1 to 300 μm, or 3 to 100 μm, or 5 to 70 μm, or 6 to 35 μm, or 9 to 18 μm.

(Surface treatment layer)

On the surface of the copper foil substrate, a surface treatment layer based on one or more selected from the group consisting of a roughening treatment layer, a rust prevention layer, a heat-resistant layer, and a silane coupling treatment layer is preferably formed. The surface treatment layer of the present invention may be formed on the adhesion surface (M surface) with the resin as described above, or on the surface (S surface) opposite to the adhesion surface (M surface), or on both surfaces.

The roughening treatment can be performed, for example, by forming roughened particles with copper or a copper alloy. The roughening process may be fine. After the roughening treatment, a covering plating treatment may be performed. The surface treatment layer formed by such roughening treatment, rust prevention treatment, heat treatment, silane treatment, immersion treatment in a treatment liquid, or plating treatment may also contain a material selected from the group consisting of Cu, Ni, Fe, Co, and Zn. , Cr, Mo, W, P, As, Ag, Sn, Ge in any group of simple substance or any one or more alloys, or organic matter.

In order to suppress the influence of ferromagnetic metals on the transmission characteristics, The total adhesion amount of Co, Ni, and Fe in the physical layer is controlled to be less than a predetermined amount as described below, and Zn, which does not show strong magnetism at normal temperature, is used as an alternative component, thereby further reducing high-frequency transmission loss. Therefore, the surface treatment layer has a Zn metal layer or an alloy treatment layer containing Zn. The alloy-treated layer containing Zn may be a Cu-Zn alloy layer. By using a Cu-Zn alloy layer, heat resistance and chemical resistance can be improved compared to a metal layer made of Zn alone.

When the surface treatment layer is a roughened layer, a rust-proof layer, a heat-resistant layer, and a silane coupler In the case where any one of the treatment layers is formed, the order of the layers is not particularly limited. For example, a roughening treatment layer may be formed on the surface of a copper foil, and a Zn metal layer or a Zn-containing layer may be provided on the roughening treatment layer. The alloy-treated layer serves as a rust-proof and heat-resistant layer. A chromic acid treatment layer may be provided on the Zn metal layer or the Zn-containing alloy treatment layer. Furthermore, a silane coupling treatment layer may be provided on the chromic acid treatment layer.

(Metal adhesion amount)

In the surface-treated copper foil of the present invention, the total adhesion amount of Co, Ni, and Fe in the surface-treated layer is controlled to 1000 μg / dm ² or less. As described above, the surface-treated copper foil of the present invention controls the adhesion amount of Co, Ni, and Fe, which are relatively high in magnetic permeability and relatively low in electric conductivity, as a cause of transmission loss, so that high-frequency transmission loss can be reduced. The total adhesion amount of Co, Ni, and Fe in the surface treatment layer is preferably 500 μg / dm ² or less, more preferably 300 μg / dm ² or less, and even more preferably 0 μg / dm ² (indicating the quantitative lower limit of analysis).

When the surface treatment layer includes a roughening treatment layer, the Cu adhesion amount in the roughening treatment layer is preferably 0.10 g / dm ² or less. According to this configuration, high-frequency transmission loss can be further reduced. The Cu adhesion amount in the roughened layer is more preferably 0.09 g / dm ² or less, even more preferably 0.08 g / dm ² or less, and typically 0.04 to 0.08 g / dm ² .

The adhesion amount of Zn in the surface treatment layer is preferably 5 mg / dm ² or less. With this configuration, chemical resistance is improved, and heat resistance is improved. The Zn adhesion amount in the surface treatment layer is more preferably 4.5 mg / dm ² or less, even more preferably 4 mg / dm ² or less, and typically 0.1 to 4.5 mg / dm ² .

The total adhesion amount of Cu, Zn, Co, Ni, and Fe in the surface treatment layer is preferably 0.10 g / dm ² or less. According to this configuration, high-frequency transmission loss can be further reduced. The total adhesion amount of Cu, Zn, Co, Ni, and Fe in the surface treatment layer is more preferably 0.09 g / dm ² or less, even more preferably 0.08 g / dm ² or less, and typically 0.04 to 0.08 g / dm ² .

(Surface roughness Rz)

The roughness of the copper foil surface is the main cause of conductor loss. The smaller the roughness, the smaller the transmission loss. From such a viewpoint, the surface-treated copper foil of the present invention can control the surface roughness Rz JIS of at least one surface to 2.2 μm or less, and can reduce transmission loss well. The surface roughness Rz JIS of both surfaces is preferably 2.2 μm or less. According to this configuration, high-frequency transmission loss can be further reduced.

The surface roughness Rz JIS is more preferably 1.5 μm or less, even more preferably 1.2 μm or less, and typically 0.5 to 2.2 μm.

(Surface area ratio)

In addition to the surface roughness Rz previously controlled for high-frequency copper foil, the three-dimensional surface area must be more accurately represented than the two-dimensional surface area in contact with the resin (dielectric) that affects high-frequency transmission loss. The ratio is controlled in an appropriate range. From this point of view, the surface-treated copper foil of the present invention has a ratio of the three-dimensional surface area to the two-dimensional surface area measured by a laser microscope on the surface of the surface-treated layer controlled to 1.0 to 1.9, so that it can be used even in high-frequency circuit substrates. , Transmission loss can also be better suppressed. This surface area ratio cannot be defined as a value less than 1.0, and if it exceeds 1.9, there is a possibility that a high-frequency transmission loss may increase. The surface area is preferably 1.0 ~ 1.9, It is more preferably 1.0 to 1.6, and even more preferably 1.3 to 1.6.

(Manufacturing method of surface treated copper foil)

In the present invention, one or both surfaces of a copper foil substrate (rolled copper foil or electrolytic copper foil) is preferably subjected to a roughening treatment of nodular electrodeposition on the surface of the copper foil after pickling. By the roughening treatment, adhesiveness (peel strength) with the resin (dielectric) is obtained. In the present invention, the roughening treatment may be performed by any element or any one selected from the group consisting of Cu, Ni, Fe, Co, Zn, Cr, Mo, W, P, As, Ag, Sn, and Ge. One or more alloys are plated, or surface treatment of an organic substance is used. In general, copper plating or the like may be used as a pretreatment before roughening, or after the roughening, in order to impart heat resistance and chemical resistance, the above-mentioned metal may be subjected to cover plating as a surface treatment. In addition, without roughening, any elementary substance or any element selected from the group consisting of Cu, Ni, Fe, Co, Zn, Cr, Mo, W, P, As, Ag, Sn, and Ge may be performed. Plating of the above alloys. Then, in order to provide heat resistance and chemical resistance, cover plating with the above-mentioned metal may be used as a surface treatment. When the roughening treatment is performed, there is an advantage that the adhesion strength with the resin becomes high. In addition, when the roughening treatment is not performed, there are advantages in that the manufacturing steps of the surface-treated copper foil are simplified, so that productivity is improved, costs can be reduced, and roughness can be reduced. For rolled copper foil and electrolytic copper foil, the content of the treatment may be slightly different. By adjusting the composition, plating time, and current density of the plating treatment on the surface of such a copper foil, the total adhesion amount of Co, Ni, and Fe in the surface treatment layer of the present invention can be controlled to form Zn metal in the surface treatment layer. Layer or an alloy-treated layer containing Zn, and controls the ratio of the three-dimensional surface area to the two-dimensional surface area measured by the laser microscope on the surface of the surface-treated layer, thereby controlling the surface roughness Rz JIS.

The electrolytic copper foil having a surface roughness Rz in the above range can be obtained by the following method: Method of making.

<Electrolyte composition>

Copper: 90 ~ 110g / L

Sulfuric acid: 90 ~ 110g / L

Chlorine: 50 ~ 100ppm

Leveling agent 1 (bis (3-sulfopropyl) disulfide): 10 ~ 30ppm

Leveling agent 2 (amine compound): 10 ~ 30ppm

As the amine compound, an amine compound of the following chemical formula can be used.

(In the above chemical formula, R ₁ and R ₂ are selected from the group consisting of a hydroxyalkyl group, an ether group, an aryl group, an aromatic-substituted alkyl group, an unsaturated hydrocarbon group, and an alkyl group).

<Manufacturing conditions>

Current density: 70 ~ 100A / dm ²

Electrolyte temperature: 50 ~ 60 ℃

Linear speed of electrolyte: 3 ~ 5m / sec

Electrolysis time: 0.5 ~ 10 minutes

The surface-treated copper foil of the present invention can be bonded to a resin base from the surface-treated layer side Laminated board. If necessary, the surface-treated copper foil may be further processed to form a circuit, thereby producing a printed wiring board or the like. The resin substrate is not particularly limited as long as it has characteristics applicable to printed wiring boards or printed circuit boards. For example, for rigid PWB, paper substrate phenol resin, paper substrate epoxy resin, and synthetic fiber cloth substrate can be used. Material epoxy resin, fluororesin impregnated cloth, glass cloth-paper composite substrate epoxy resin, glass cloth-glass nonwoven composite substrate epoxy resin and glass cloth substrate epoxy resin, etc., flexible printed circuit board (FPC) Polyester film or polyimide film, liquid crystal polymer (LCP) film, fluororesin and fluororesin-polyimide composite materials can be used. Furthermore, since the dielectric loss of the liquid crystal polymer (LCP) is small, it is preferable to use a liquid crystal polymer (LCP) film for printed wiring boards or printed circuit boards for high-frequency circuit applications. Furthermore, in the present invention, the "printed wiring board" also includes a printed wiring board, a printed circuit board, and a printed circuit board on which components are mounted. In addition, two or more printed wiring boards of the present invention may be connected, and a printed wiring board to which two or more printed wiring boards are connected may be manufactured. At least one printed wiring board of the present invention may be connected to another printed wiring board. The printed wiring board of the present invention or a printed wiring board that is not equivalent to the printed wiring board of the present invention is connected, and an electronic device is manufactured using this printed wiring board. Furthermore, in the present invention, the "copper circuit" also includes copper wiring.

Regarding the bonding method, in the case of rigid PWB, prepare to make glass cloth The substrate is impregnated with resin, and the resin is hardened to a semi-hardened prepreg. This can be performed by overlapping a copper foil with a prepreg and applying heat and pressure. In the case of FPC, a substrate such as a liquid crystal polymer or a polyimide film is bonded to a copper foil laminate at a high temperature and pressure via a bonding agent or without a bonding agent, or a polyimide precursor is coated, By drying, hardening, etc., a laminated board can be manufactured.

The laminated board of the present invention can be used in various printed wiring boards (PWB) or printed wiring boards. There are no particular restrictions on road boards. As a printed wiring board, for example, from the viewpoint of the number of layers of a conductor pattern In other words, it can be applied to single-sided PWB, double-sided PWB, multilayer PWB (3 or more layers), and from the viewpoint of the type of insulating substrate material, it can be applied to rigid PWB, flexible PWB (FPC), and rigid-elastic PWB.

Furthermore, as another embodiment, the present invention may also be a surface-treated copper foil described below. A surface-treated layer is formed on at least one surface. The surface-treated layer includes a roughened layer. Co, The total adhesion amount of Ni and Fe is 300 μg / dm ² or less. The surface treatment layer has a Zn metal layer or an alloy treatment layer containing Zn. The surface of the surface treatment layer has a three-dimensional surface area relative to a two-dimensional surface area measured by a laser microscope. The ratio is 1.0 to 1.9, the surface roughness Rz JIS of at least one surface is 2.2 μm or less, the surface treatment layer is formed on both surfaces, and the surface roughness Rz JIS of the two surfaces is 2.2 μm or less.

Furthermore, as another embodiment, the present invention may also be a surface-treated copper foil described below. A surface-treated layer is formed on at least one surface. The surface-treated layer includes a roughened layer. Co, The total adhesion amount of Ni and Fe is 300 μg / dm ² or less. The surface treatment layer has a Zn metal layer or an alloy treatment layer containing Zn. The surface of the surface treatment layer has a three-dimensional surface area relative to a two-dimensional surface area measured by a laser microscope. The ratio is 1.0 to 1.9, the surface roughness Rz JIS of at least one surface is 2.2 μm or less, and the above-mentioned Zn-containing alloy treatment layer is a Cu-Zn alloy layer.

Furthermore, as another embodiment, the present invention may also be a surface-treated copper foil as described below. A surface-treated layer is formed on at least one surface. The surface-treated layer includes a roughened layer, and Co, The total adhesion amount of Ni and Fe is 300 μg / dm ² or less. The surface treatment layer has a Zn metal layer or an alloy treatment layer containing Zn. The surface of the surface treatment layer has a three-dimensional surface area relative to a two-dimensional surface area measured by a laser microscope. The ratio is 1.0 to 1.9, the surface roughness Rz JIS of at least one surface is 2.2 μm or less, and the total adhesion amount of Cu, Zn, Co, Ni, and Fe in the surface treatment layer is 0.10 g / dm ² or less.

Furthermore, as another embodiment, the present invention may be a surface-treated copper foil as described below. A surface-treated layer is formed on at least one surface. The total adhesion amount of Co, Ni, and Fe in the surface-treated layer is 986 μg / dm. ² or less, the surface treatment layer a metal layer having a Zn or Zn alloy containing treatment layer of the surface treatment layer surface measured by a laser microscope with respect to surface area ratio of the three-dimensional surface area is 1.0 to 1.9, is formed on both surfaces The surface treatment layer is provided, and the surface roughness Rz JIS of the two surfaces is 0.6 μm or less.

(With carrier copper foil)

As another embodiment of the present invention, the copper foil with a carrier has an intermediate layer and an ultra-thin copper layer in this order on one or both sides of the carrier. The ultra-thin copper layer is a surface-treated copper foil according to an embodiment of the present invention.

<Carrier>

The carrier that can be used in the present invention is typically a metal foil or a resin film, such as copper foil, copper alloy foil, nickel foil, nickel alloy foil, iron foil, iron alloy foil, stainless steel foil, aluminum foil, aluminum alloy foil, insulating resin film ( For example, polyimide film, liquid crystal polymer (LCP) film, polyethylene terephthalate (PET) Film, polyamide film, polyester film, fluororesin film, etc.).

As a carrier usable in the present invention, copper foil is preferably used. This is because the copper foil has a high electrical conductivity, so it is easy to form an intermediate layer and an extremely thin copper layer thereafter. The carrier is typically provided in the form of a rolled copper foil or an electrolytic copper foil. Generally speaking, electrolytic copper foil is produced by electrolyzing copper from a copper sulfate plating bath onto a titanium or stainless steel drum, and rolled copper foil is produced by repeatedly performing plastic processing and heat treatment using a calender roll. As the material of the copper foil, in addition to high-purity copper such as refined copper or oxygen-free copper, for example, copper doped with Sn, copper doped with Ag, copper alloy added with Cr, Zr, or Mg, and Ni may be added. Copper alloys such as Carson-based copper alloys such as Si.

Regarding the thickness of the carrier that can be used in the present invention, there is no particular limitation as long as it is appropriate What is necessary is just to adjust it to a suitable thickness as a carrier, and it can be set to 5 micrometers or more, for example. However, if it is too thick, the production cost will increase, so it is usually preferably 35 μm or less. Therefore, the thickness of the carrier is typically 12 to 70 μm, and more typically 18 to 35 μm.

In addition, the carrier used in the present invention can be controlled to form an intermediate layer as described below. The surface roughness Rz and the surface area ratio of the side, and the surface roughness Rz and the surface area ratio of the surface of the ultra-thin copper layer after the surface treatment (that is, the surface of the surface treatment layer) are controlled.

Regarding the carrier used in the present invention, the shape of the carrier before the intermediate layer is formed is controlled in advance The roughness (Rz) and surface area ratio of the TD of the surface forming the side of the intermediate layer are also important. Specifically, the surface roughness (Rz) of the TD of the carrier before the formation of the intermediate layer is 0.20 to 1.50 μm, preferably 0.20 to 1.00 μm, and the surface area ratio is 1.0 to 1.9, preferably 1.0 to 1.5. Such a copper foil can be produced by adjusting the oil film equivalent of the rolling oil to perform rolling, chemical polishing such as chemical etching or electrolytic polishing in a phosphoric acid solution, and adding predetermined additives to produce an electrolytic copper foil. . The surface roughness (Rz) of the TD of the copper foil before processing is The surface area ratio is set to the above range, and the surface roughness (Rz) and surface area ratio of the copper foil after processing can be easily controlled.

The rolling can be performed by setting the oil film equivalent specified in the following formula to 13,000 to 35,000.

Oil film equivalent = {(rolling oil viscosity [cSt]) × (crossing speed [mPm] + roller peripheral speed [mpm])} / {(roller bite angle [rad]) × (material falling stress [kg / mm ² ])}

The rolling oil viscosity [cSt] is a dynamic viscosity at 40 ° C.

In order to lower the oil film equivalent in the range of 13,000 to 35,000, a known method such as using a low-viscosity rolling oil or slowing down the board speed can be used. In addition, in order to make the oil film equivalent in the range of 13,000 to 35,000 higher, a known method such as using a high-viscosity calender oil or increasing the plate speed can be used.

An electrolytic copper foil having a surface roughness Rz and a surface area ratio within the above range can be produced by the following method. This electrolytic copper foil can be used as a carrier.

<Electrolyte composition>

Copper: 90 ~ 110g / L

Sulfuric acid: 90 ~ 110g / L

Chlorine: 50 ~ 100ppm

Leveling agent 1 (bis (3-sulfopropyl) disulfide): 10 ~ 30ppm

Leveling agent 2 (amine compound): 10 ~ 30ppm

As the amine compound, an amine compound of the following chemical formula can be used.

(In the above chemical formula, R ₁ and R ₂ are selected from the group consisting of a hydroxyalkyl group, an ether group, an aryl group, an aromatic-substituted alkyl group, an unsaturated hydrocarbon group, and an alkyl group).

<Manufacturing conditions>

Current density: 70 ~ 100A / dm ²

Electrolyte temperature: 50 ~ 60 ℃

Linear speed of electrolyte: 3 ~ 5m / sec

Electrolysis time: 0.5 ~ 10 minutes (adjusted according to the copper thickness and current density)

Furthermore, a roughening treatment layer may be provided on the surface on the side where the ultra-thin copper layer is provided on the carrier as the surface on the opposite side. The roughening treatment layer may be provided by a known method, or the roughening treatment layer may be provided by the above-mentioned roughening treatment. The case where the roughened layer is provided on the surface on the side where the ultra-thin copper layer is provided on the opposite side of the carrier has the advantage that when the carrier is laminated from a surface side having the roughened layer on a support such as a resin substrate, the carrier It becomes difficult to peel off from the resin substrate.

<Middle layer>

An intermediate layer is provided on the carrier. Other layers may be provided between the carrier and the intermediate layer. The intermediate layer used in the present invention is not particularly limited as long as it has a structure as follows: before the step of laminating the copper foil with a carrier onto an insulating substrate, it is difficult to peel the ultra-thin copper layer from the carrier. After the step of laminating the insulating substrate, the ultra-thin copper layer can be peeled from the carrier. For example, the intermediate layer of the copper foil with a carrier of the present invention may also contain a material selected from the group consisting of Cr, Ni, Co, Fe, Mo, Ti, W, P, Cu, Al, Zn, these alloys, these hydrates, One or two or more of these oxides and organic compounds. The intermediate layer may be a plurality of layers.

In addition, for example, the intermediate layer may be configured by forming one element selected from the group consisting of Cr, Ni, Co, Fe, Mo, Ti, W, P, Cu, Al, and Zn from the carrier side. A single metal layer or 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, and Zn, A hydrate, oxide, or organic substance of one or more elements selected from the group consisting of Cr, Ni, Co, Fe, Mo, Ti, W, P, Cu, Al, and Zn is formed thereon The layer of composition.

In addition, for example, the intermediate layer may be formed by forming one element selected from the group consisting of Cr, Ni, Co, Fe, Mo, Ti, W, P, Cu, Al, and Zn from the carrier side. A single metal layer, or 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, and A single metal layer composed of one element selected from the group consisting of Cr, Ni, Co, Fe, Mo, Ti, W, P, Cu, Al, and Zn is formed thereon, or a metal layer selected from Cr, Ni An alloy layer composed of one or two or more elements in the element group consisting of, Co, Fe, Mo, Ti, W, P, Cu, Al, and Zn.

The intermediate layer may use a known organic substance as the organic substance, and it is preferable to use any one or more of a nitrogen-containing organic compound, a sulfur-containing organic compound, and a carboxylic acid. For example, as the specific nitrogen-containing organic compound, 1,2,3-benzotriazole, carboxybenzotriazole, N ', N'-bis (benzotriazole), which is a triazole compound having a substituent, are preferably used. Oxazolylmethyl) urea, 1H-1,2,4-triazole, and 3-amino-1H-1,2,4-triazole.

As the sulfur-containing organic compound, mercaptobenzothiazole, sodium 2-mercaptobenzothiazole, thiocyanuric acid, 2-benzimidazole thiol, and the like are preferably used.

As the carboxylic acid, a monocarboxylic acid is particularly preferably used, and among them, oleic acid, linoleic acid, and linolenic acid are preferably used.

For example, the intermediate layer may be formed by sequentially stacking a nickel layer, a nickel-phosphorus alloy layer or a nickel-cobalt alloy layer, and a chromium-containing layer on a carrier. The adhesion force between nickel and copper is higher than the adhesion force between chromium and copper. Therefore, when the ultra-thin copper layer is peeled off, peeling occurs at the interface between the ultra-thin copper layer and the chromium-containing layer. Further, for the nickel in the intermediate layer, a barrier effect to prevent the copper component from diffusing from the carrier to the ultra-thin copper layer is expected. The amount of deposition of nickel intermediate layer is preferably from 100μg / dm ² or more 40000μg / dm ² or less, more preferably 100μg / dm ² or more 4000μg / dm ² or less, more preferably 100μg / dm ² or more 2500μg / dm ² or less, It is more preferably 100 μg / dm ² or more and less than 1000 μg / dm ² , and the adhesion amount of chromium in the intermediate layer is preferably 5 μg / dm ² or more and 100 μg / dm ² or less. When an intermediate layer is provided only on one side, it is preferable to provide a rust-proof layer such as a Ni plating layer on the opposite side of the carrier. The chromium layer of the intermediate layer can be provided by chromium plating or chromic acid treatment.

If the thickness of the intermediate layer becomes too large, the thickness of the intermediate layer may affect the surface roughness Rz and gloss of the surface of the ultra-thin copper layer after the surface treatment. The layer thickness is preferably 1 to 1000 nm, preferably 1 to 500 nm, preferably 2 to 200 nm, preferably 2 to 100 nm, and more preferably 3 to 60 nm. Furthermore, the intermediate layer may be provided on both sides of the carrier.

<Ultra-thin copper layer>

An extremely thin copper layer is provided on the intermediate layer. Other layers may be provided between the intermediate layer and the ultra-thin copper layer. An extremely thin copper layer having the carrier is a surface-treated metal according to an embodiment of the present invention material. The thickness of the ultra-thin copper layer is not particularly limited, and is generally thinner than the carrier, for example, 12 μm or less. It is typically 0.5 to 12 μm, and more typically 1.5 to 5 μm. In addition, before the ultra-thin copper layer is provided on the intermediate layer, in order to reduce pinholes in the ultra-thin copper layer, a strike plating using a copper-phosphorus alloy may be performed. Examples of the primer plating include copper pyrophosphate plating solution. Furthermore, an ultra-thin copper layer can also be provided on both sides of the carrier. The ultra-thin copper layer may be a layer containing a copper alloy or a layer composed of a copper alloy, and the ultra-thin copper layer may also contain an organic substance or an inorganic substance. Furthermore, as the ultra-thin copper layer, an ultra-thin copper layer having a Cu concentration of 75 mass% or more is preferably used. The reason is that an extremely thin copper layer having a Cu concentration of 75 mass% or more has high electrical conductivity, and is suitable for applications such as circuits.

The ultra-thin copper layer of the present invention may be an ultra-thin copper layer formed under the following conditions. The reason is that the surface roughness Rz and the surface area ratio of the surface treatment layer of the copper foil with a carrier are controlled by forming a smooth ultra-thin copper layer.

组成 Electrolyte composition

Copper: 80 ~ 120g / L

Sulfuric acid: 80 ~ 120g / L

Chlorine: 30 ~ 100ppm

Leveling agent 1 (bis (3-sulfopropyl) disulfide): 10 ~ 30ppm

Leveling agent 2 (amine compound): 10 ~ 30ppm

As the amine compound, an amine compound of the following chemical formula can be used.

(In the above chemical formula, R ₁ and R ₂ are selected from the group consisting of a hydroxyalkyl group, an ether group, an aryl group, an aromatic-substituted alkyl group, an unsaturated hydrocarbon group, and an alkyl group).

˙Manufacturing conditions

Current density: 70 ~ 100A / dm ²

Electrolyte temperature: 50 ~ 65 ℃

Linear speed of electrolyte: 1.5 ~ 5m / sec

Electrolysis time: 0.5 ~ 10 minutes (adjusted according to the copper thickness and current density)

Hereinafter, some examples of manufacturing steps of a printed wiring board using the copper foil with a carrier of the present invention will be disclosed.

An embodiment of the method for manufacturing a printed wiring board of the present invention includes the following steps: a step of preparing the copper foil with a carrier and an insulating substrate of the present invention; a step of laminating the copper foil with a carrier and an insulating substrate; After the copper foil and the insulating substrate are laminated in such a way that the ultra-thin copper layer side faces the insulating substrate, the copper-clad laminated board is formed through the step of peeling the carrier of the copper foil with a carrier, and then the semi-additive method is used to improve the semi-additive The steps of forming a circuit by any of the formation method, partial addition method, and subtraction method. The insulating substrate may also be an insulating substrate having an inner-layer circuit.

In the present invention, the so-called semi-additive method refers to the following method: on an insulating substrate or copper A thin electroless plating is performed on the foil seed layer to form a pattern, and then a conductor pattern is formed using plating and etching.

Therefore, a method for manufacturing a printed wiring board of the present invention using a semi-additive method The embodiment includes the following steps: a step of preparing the copper foil with a carrier and an insulating substrate of the present invention; a step of laminating the copper foil with a carrier and an insulating substrate; a layer of the copper foil with a carrier and an insulating substrate; The step of peeling the carrier of the copper foil; the step of completely removing the ultra-thin copper layer exposed by peeling the carrier by etching using an etching solution such as an acid or plasma, etc .; and removing the ultra-thin copper layer by etching The above-mentioned resin exposed and removed is provided with a step of through hole or / and blind via; a step of performing desmear treatment on the area containing the above hole or / and blind via; A step of providing an electroless plating layer on the above resin and the above-mentioned perforations or / and blind holes; a step of providing a plating resist on the above electroless plating layer; exposing the above plating resist, and then plating the area where the circuit is formed The step of removing the resist; the step of providing a plating layer in the area where the circuit is formed after removing the plating resist; the step of removing the plating resist; by rapid etching (f lash etching) and the like, a step of removing an electroless plating layer existing in a region other than a region where the circuit is formed.

Another embodiment of the method for manufacturing a printed wiring board of the present invention using a semi-additive method The embodiment includes the following steps: preparing the copper foil with a carrier and an insulating substrate of the present invention; laminating the copper foil with a carrier and an insulating substrate; laminating the copper foil with a carrier and the insulating substrate; The step of peeling the carrier of the copper foil; the step of removing all the ultra-thin copper layer exposed by peeling the carrier by etching using an etching solution such as an acid or a plasma; the method of removing the ultra-thin copper layer by etching A step of providing an electroless plating layer on the surface of the resin that is removed and exposed; a step of providing a plating resist on the electroless plating layer; and exposing the plating resist Light, and then the step of removing the plating resist in the area where the circuit is formed; the step of providing a plating layer in the area where the circuit is formed after removing the plating resist; the step of removing the plating resist; A step of removing an electroless plating layer and an ultra-thin copper layer existing in a region other than a region where the circuit is formed by etching or the like.

In the present invention, the so-called modified semi-additive method refers to the following method: on the insulating layer Laminated metal foil protects the non-circuit forming part with a plating resist. After the copper thickness of the circuit forming part is increased by electroplating, the resist is removed, and the metal foil other than the circuit forming part is removed by (rapid) etching. A circuit is formed on the insulating layer.

Therefore, a method for manufacturing a printed wiring board of the present invention using an improved semi-additive method In one embodiment, the method includes the following steps: preparing the copper foil with a carrier and an insulating substrate of the present invention; laminating the copper foil with a carrier and an insulating substrate; laminating the copper foil with a carrier and the insulating substrate; The step of peeling the carrier with the copper foil with the carrier; the step of setting a perforation or / and a blind hole in the ultra-thin copper layer and the insulating substrate exposed by peeling the above carrier; and removing the glue in the area containing the perforation or / and the blind hole Step of slag treatment; step of providing an electroless plating layer on the area containing the above-mentioned perforations or / and blind holes; step of setting a plating resist on the surface of the ultra-thin copper layer exposed by peeling the carrier; setting of the above-mentioned plating resist A step of forming a circuit by electroplating after plating; a step of removing the above-mentioned plating resist; a step of removing an extremely thin copper layer exposed by removing the above-mentioned plating resist by rapid etching.

In addition, the step of forming a circuit on the resin layer may be an additional step The carrier copper foil is bonded to the resin layer from the side of the ultra-thin copper layer, and the above-mentioned circuit is formed by using the copper foil with a carrier attached to the resin layer. Moreover, another copper foil with a carrier adhered to the said resin layer may also be the copper foil with a carrier of this invention. In addition, the step of forming a circuit on the resin layer, It may be performed by any one of a semi-additive method, a subtractive method, a partial additive method, or an improved semi-additive method. Moreover, the copper foil with a carrier which forms a circuit on the said surface may have a board | substrate or a resin layer on the surface of the said copper foil with a carrier.

Another method for manufacturing a printed wiring board of the present invention using an improved semi-additive method In one embodiment, the method includes the following steps: preparing the copper foil with a carrier and an insulating substrate according to the present invention; laminating the copper foil with a carrier and an insulating substrate; laminating the copper foil with a carrier and the insulating substrate; The step of peeling the carrier of the copper foil of the carrier; the step of setting a plating resist on the extremely thin copper layer exposed by peeling the carrier; exposing the above plating resist, and then plating the resist in the area where the circuit is formed A step of removing; a step of providing an electroplated layer in a region where the above-mentioned circuit is formed by removing the above-mentioned plating resist; a step of removing the above-mentioned plating resist; by rapid etching etc., it will exist outside the region where the above-mentioned circuit is formed Step of removing the electroless plating layer and the ultra-thin copper layer in the area.

In the present invention, the so-called partial addition method refers to a method in which a conductive layer is provided The formed substrate and the substrate with holes or via holes (if necessary) are provided with a catalyst core and etched to form a conductor circuit. If necessary, a solder resist or a plating resist is provided, and then the above conductor is provided. On a circuit, a printed wiring board is manufactured by thickening perforations, through holes, and the like by an electroless plating process.

Therefore, in the method for manufacturing a printed wiring board of the present invention using a partial addition method, In one embodiment, the method includes the following steps: preparing the copper foil with a carrier and an insulating substrate according to the present invention; laminating the copper foil with a carrier and an insulating substrate; laminating the copper foil with a carrier and the insulating substrate; The step of peeling the carrier of the copper foil of the carrier; the step of providing a perforation or / and a blind hole in the ultra-thin copper layer and the insulating substrate exposed by peeling the above carrier; / And the process of removing the glue residue in the area of the blind hole; the step of providing a catalyst core to the area containing the above-mentioned perforation or / and the blind hole; Step; a step of exposing the resist to form a circuit pattern; a step of forming a circuit by removing the ultra-thin copper layer and the catalyst core by an etching method using an etching solution such as an acid or a plasma; The step of removing the above-mentioned resist; setting a solder resist or plating on the surface of the insulating substrate exposed by removing the ultra-thin copper layer and the catalyst core by using etching or plasma using an etching solution such as an acid, etc. Resist step; a step of providing an electroless plating layer in an area where the above solder resist or plating resist is not provided.

In the present invention, the so-called subtractive method refers to the following method: selection by etching or the like The unnecessary part of the copper foil on the copper-clad laminated board is removed, and a conductor pattern is formed.

Therefore, it is one of the methods for manufacturing a printed wiring board of the present invention using a subtractive method. The embodiment includes the following steps: preparing the copper foil with a carrier and an insulating substrate of the present invention; laminating the copper foil with a carrier and an insulating substrate; laminating the copper foil with a carrier and the insulating substrate; The step of peeling the carrier of the copper foil; the step of providing perforations or blind holes in the ultra-thin copper layer and the insulating substrate exposed by peeling the above-mentioned carrier; Step; a step of providing an electroless plating layer on the area containing the above-mentioned perforations or / and blind holes; a step of providing a plating layer on the surface of the above-mentioned electroless plating layer; providing a resist on the surface of the above-mentioned plating layer or / and the ultra-thin copper layer Step of exposing the resist; forming a circuit pattern by exposing the resist; removing the ultra-thin copper layer, the electroless plating layer, and the electroplating layer by etching or plasma using an etching solution such as an acid, A step of forming a circuit; a step of removing the resist.

Another implementation of the printed wiring board manufacturing method of the present invention using the subtractive method The form includes the following steps: preparing the copper foil with a carrier and an insulating substrate of the present invention; laminating the copper foil with a carrier and the insulating substrate; laminating the copper foil with a carrier and the insulating substrate; The step of peeling the carrier of the foil; the step of providing perforations or blind holes in the ultra-thin copper layer and the insulating substrate exposed by peeling the above carrier; Steps: a step of providing an electroless plating layer on the area containing the above-mentioned perforations or / and blind holes; a step of forming a mask on the surface of the above electroless plating layer; a step of providing a plating layer on the surface of the above electroless plating layer where no mask is formed ; A step of providing a resist on the surface of the above-mentioned electroplated layer or / and the above-mentioned extremely thin copper layer; a step of exposing the above-mentioned resist to form a circuit pattern; by an etching method using an etching solution such as an acid or a plasma A step of removing the ultra-thin copper layer and the electroless plating layer to form a circuit; and a step of removing the resist.

The step of setting perforation or / and blind hole and the subsequent step of removing glue residue can be omitted. Row.

Here, the manufacturing of a printed wiring board using the copper foil with a carrier of the present invention will be described in detail. Specific examples of methods. Here, although a copper foil with a carrier having an ultra-thin copper layer formed with a roughened layer is described as an example, the present invention is not limited to this. The carrier copper foil can be similarly subjected to the following printed wiring board manufacturing method.

First, a copper foil with a carrier (first layer) having an ultra-thin copper layer having a roughened layer formed on the surface is prepared.

Next, a resist is coated on the roughened layer of the ultra-thin copper layer, exposed and developed, and the resist is etched into a predetermined shape.

Secondly, after forming a plating for a circuit, the resist is removed, thereby forming a circuit plating of a predetermined shape.

Next, the resin layer is laminated on the ultra-thin copper layer by covering the circuit plating method (the method of burying the circuit plating method), and then the other copper foil with a carrier (the second layer) is placed from the side of the ultra-thin copper layer. then.

Next, the carrier was peeled from the copper foil with a carrier of the second layer.

Secondly, laser drilling is performed at a predetermined position of the resin layer to expose the circuit plating and form blind holes.

Second, copper is buried in the blind via to form a via fill.

Next, a circuit plating is formed on the hole filling in the manner described above.

Next, the carrier was peeled from the first layer of copper foil with a carrier.

Secondly, the ultra-thin copper layers on both surfaces are removed by rapid etching, so that the surface of the circuit plating in the resin layer is exposed.

Second, bumps are formed on the circuit plating in the resin layer, and copper pillars are formed on the solder. In this way, a printed wiring board using the copper foil with a carrier of the present invention was produced.

The above additional copper foil with carrier (second layer) can be used with the carrier of the present invention As the copper foil, a conventional copper foil with a carrier may be used, and further, a usual copper foil may be used. In addition, a circuit of one layer or a plurality of layers can be formed on the circuit of the second layer, and any one of a semi-additive method, a subtractive method, a partial additive method, or an improved semi-additive method can be used. Perform such circuit formation.

The copper foil with a carrier of the present invention is preferably controlled to be extremely thin in a manner satisfying the following (1) Color difference on the surface of the copper layer. In the present invention, the "color difference on the surface of the ultra-thin copper layer" means the color difference on the surface of the ultra-thin copper layer, or the color difference on the surface of the surface-treated layer when various surface treatments such as roughening treatment are performed. That is, the copper foil with a carrier of the present invention preferably satisfies the following (1) to control the color difference of the roughened surface of the ultra-thin copper layer. Furthermore, the surface-treated gold of the present invention The term "roughened surface" refers to the case where after the roughening treatment, a surface treatment for providing a heat-resistant layer, a rust-proof layer, and a weather-resistant layer is performed, the surface treatment after the surface treatment is performed. The surface of a metal material (extremely thin copper layer). When the surface-treated metal material is an extremely thin copper layer with a copper foil with a carrier, the so-called "roughened surface" refers to the provision of a heat-resistant layer, a rust-proof layer, and weather resistance after the roughening treatment. In the case of a surface treatment of a layer or the like, the surface of the ultra-thin copper layer after the surface treatment is performed.

(1) Regarding the color difference on the surface of the ultra-thin copper layer, the color difference ΔE * ab based on JIS Z8730 is 45 or more.

Here, the color differences ΔL, △ a, and Δb are measured by a color difference meter, respectively, and the black / White / red / green / yellow / blue, a comprehensive indicator expressed using the L * a * b color system based on JIS Z8730, in the form of △ L: white and black, △ a: red and green, △ b: yellow and blue Means. In addition, ΔE * ab is expressed by the following formula using these color differences.

The aforementioned color difference can be adjusted by increasing the current density when forming an extremely thin copper layer, reducing the copper concentration in the plating solution, and increasing the linear flow velocity of the plating solution.

In addition, the aforementioned chromatic aberration can also be adjusted by providing a roughening treatment layer by performing a roughening treatment on the surface of the ultra-thin copper layer. When a roughening treatment layer is provided, an electrolytic solution containing copper and one or more elements selected from the group consisting of nickel, cobalt, tungsten, and molybdenum can be used to make the current density higher than the conventional current density ( For example, 40 to 60 A / dm ² ), the processing time is adjusted to be shorter than the conventional processing time (for example, 0.1 to 1.3 seconds). In the case where the surface of the ultra-thin copper layer is not provided with a roughening treatment layer, it can be achieved by using a plating bath having a Ni concentration of 2 times or more of other elements, and using a current density lower than that in the past ( 0.1 ~ 1.3A / dm ² ), and set the processing time (20 seconds ~ 40 seconds) longer, and the surface of the ultra-thin copper layer or heat-resistant layer or rust-proof layer or chromic acid-treated layer or silane coupling treatment layer Ni alloy plating (for example, Ni-W alloy plating, Ni-Co-P alloy plating, Ni-Zn alloy plating) is performed.

Regarding the color difference on the surface of the ultra-thin copper layer, if the color difference based on JIS Z8730 is △ E * If ab is 45 or more, for example, when a circuit is formed on the surface of an ultra-thin copper layer with a copper foil with a carrier, the contrast between the ultra-thin copper layer and the circuit becomes clear. As a result, the visibility is improved, and the circuit position can be accurately performed alignment. The color difference ΔE * ab of the surface of the ultra-thin copper layer based on JIS Z8730 is preferably 50 or more, more preferably 55 or more, and even more preferably 60 or more.

When the color difference of the surface of the ultra-thin copper layer is controlled in the above manner, The contrast becomes clear and the visibility becomes better. Therefore, in the manufacturing steps of the printed wiring board as described above, it is possible to form a circuit plating at a predetermined position with high accuracy. In addition, according to the manufacturing method of the printed wiring board as described above, the circuit plating is embedded with a resin layer. Therefore, for example, when the ultra-thin copper layer is removed by rapid etching as described above, the circuit plating is protected by the resin layer and has a shape. It is maintained, thereby making it easy to form a minute circuit. In addition, since the circuit plating is protected by the resin layer, the migration resistance is improved, and the conduction of the wiring of the circuit is well suppressed. Therefore, it becomes easy to form a fine circuit. In addition, when the ultra-thin copper layer is removed by rapid etching, the exposed surface of the circuit plating becomes a shape recessed from the resin layer, so it is easy to form bumps on the circuit plating, and it is easy to form the bumps thereon. Copper pillars improve manufacturing efficiency.

In addition, as the embedding resin (RESIN), a known resin or prepreg can be used. For example, BT (biscis ) Resin or prepreg of glass cloth impregnated with BT resin, ABF film or ABF made by Ajinomoto Fine-Techno Co., Ltd. As the embedding resin (resin), a resin layer and / or a resin and / or a prepreg described in this specification can be used.

The copper foil with a carrier used for the first layer is described in the table of the copper foil with a carrier. The surface may have a substrate or a resin layer. The copper foil with a carrier used for the first layer is supported by the substrate or the resin layer, and is not prone to wrinkles, so it has the advantage of improving productivity. In addition, as long as the substrate or the resin layer has the effect of supporting the copper foil with a carrier used in the first layer, all the substrates or the resin layer can be used. For example, a carrier, a prepreg, a resin layer or a known carrier, a prepreg, a resin layer, a metal plate, a metal foil, a plate of an inorganic compound, a plate of an inorganic compound, a plate of an organic compound, or an organic compound may be used as described in the specification of this case. The foil serves as the aforementioned substrate or resin layer.

[Example]

A rolled copper foil (C1100 manufactured by JX Nippon Nissei Metals Co., Ltd.) or an electrolytic copper foil with a thickness of 18 μm was prepared as the copper foil substrates of Examples 1 to 10 and Comparative Examples 1 to 6.

Next, plating was performed under the conditions shown in Tables 1 to 2 as a surface treatment. Examples 1 to 4 are surface-treated on the precipitation surface (Rz 0.6 μm) of the electrolytic copper foil produced by the above method. Examples 5 to 7 and Comparative Examples 1, 4 to 6 are for the above electrolytic copper foil. The roll surface (Rz 1.5 μm) of the foil was surface-treated. In Comparative Examples 2 and 3, the deposition surface (Rz 2.0 μm) of the produced electrolytic copper foil was surface-treated with an electrolytic solution containing no leveling agent. In addition, Examples 8 to 10 performed surface treatment on a rolled copper foil controlled to a predetermined surface roughness. Table 1 shows the liquid composition, pH value, temperature, and current density of each of the plating solutions 1 to 10. Table 2 shows that the plating treatments 1 to 3 were performed sequentially with the bath composition and time described. Furthermore, after the plating, Zn, Ni, or an alloy thereof is plated, And chromic acid treatment to ensure heat resistance and increase peel strength by applying a silane coupling agent.

The application conditions of the silane coupling agent are as follows.

˙3-Methacryl 醯 methoxypropyltrimethoxysilane

˙ Silane concentration: 0.6vol% (the rest: water)

˙Processing temperature: 30 ~ 40 ℃

˙ Processing time: 5 seconds

干燥 Drying after silane treatment: 100 ℃ × 3 seconds

In addition, the surface treatments of Examples 1, 9 and the following Example 11 are equivalent to a smooth plating treatment (a surface treatment that is not a roughening treatment), and the surface treatments in the other Examples and Comparative Examples are equivalent to a roughening treatment.化 处理。 Processed.

In addition, the copper foil with a carrier described below was prepared as a basis for Examples 11 to 15 material.

In Examples 11 to 13, an electrolytic copper foil with a thickness of 18 μm (HLP foil manufactured by JX Nippon Nissei Metal Co., Ltd.) was prepared as a carrier, and an electrolytic copper foil with a thickness of 18 μm (JX Nippon Nissei Metal Corp.) was prepared in Example 14 The manufactured JTC foil) was used as a carrier. In Example 15, a rolled copper foil (C1100 manufactured by JX Nippon Nissei Metal Co., Ltd.) with a thickness of 18 μm was prepared as a carrier. In addition, under the following conditions, an intermediate layer was formed on the surface of the carrier precipitation surface side in Examples 11 to 13, and in Example 14, an intermediate layer was formed on the surface of the carrier roller surface (gloss surface side) of the carrier. In Example 15, an intermediate layer is formed on the surface of the carrier. Then, in each embodiment, an ultra-thin copper layer is formed on the surface of the intermediate layer. In addition, when the carrier is required, the surface roughness of the surface on the side where the intermediate layer is formed before the intermediate layer is formed is controlled by the above method.

˙Example 11

<Middle layer>

(1) Ni layer (Ni plating)

The carrier was plated on a roll-to-roll continuous plating line under the following conditions to form a Ni layer with an adhesion amount of 1000 μg / dm ² . The specific plating conditions are described below.

Nickel sulfate: 270 ~ 280g / L

Nickel chloride: 35 ~ 45g / L

Nickel acetate: 10 ~ 20g / L

Boric acid: 30 ~ 40g / L

Gloss agent: saccharin, butynediol, etc.

Dodecyl sodium sulfate: 55 ~ 75ppm

pH value: 4 ~ 6

Bath temperature: 55 ~ 65 ℃

Current density: 10A / dm ²

(2) Cr layer (electrolytic chromic acid treatment)

Next, the surface of the Ni layer formed in (1) was washed with water and pickled, and then subjected to electrolytic chromic acid treatment on a roll-to-roll continuous plating line under the following conditions to make 11 μg / dm ² The Cr layer with an adhesion amount is attached to the Ni layer.

Potassium dichromate 1 ~ 10g / L, zinc 0g / L

pH value: 7 ~ 10

Liquid temperature: 40 ~ 60 ℃

Current density: 2A / dm ²

<Ultra-thin copper layer>

Next, the surface of the Cr layer formed in (2) was washed with water and pickled, and then plated on a roll-to-roll continuous plating line under the following conditions to form a 1.5 μm thick Cr layer. Ultra-thin copper layer to make ultra-thin copper foil with carrier.

Copper concentration: 90 ~ 110g / L

Sulfuric acid concentration: 90 ~ 110g / L

Chloride ion concentration: 50 ~ 90ppm

Leveling agent 1 (bis (3-sulfopropyl) disulfide): 10 ~ 30ppm

Leveling agent 2 (amine compound): 10 ~ 30ppm

The following amine compound was used as the leveling agent 2.

(In the above chemical formula, R ₁ and R ₂ are selected from the group consisting of a hydroxyalkyl group, an ether group, an aryl group, an aromatic-substituted alkyl group, an unsaturated hydrocarbon group, and an alkyl group).

Electrolyte temperature: 50 ~ 80 ℃

Current density: 100A / dm ²

Linear speed of electrolyte: 1.5 ~ 5m / sec

˙Example 12

<Middle layer>

(1) Ni-Mo layer (nickel-molybdenum alloy plating)

The carrier was electroplated on a roll-to-roll continuous plating line under the following conditions to form a Ni-Mo layer with an adhesion amount of 3000 μg / dm ² . The specific plating conditions are described below.

(Liquid composition) Ni sulfate hexahydrate: 50 g / dm ³ , sodium molybdate dihydrate: 60 g / dm ³ , sodium citrate: 90 g / dm ³

(Liquid temperature) 30 ℃

(Current density) 1 ~ 4A / dm ²

(Power-on time) 3 ~ 25 seconds

<Ultra-thin copper layer>

An extremely thin copper layer is formed on the Ni-Mo layer formed in (1). An ultra-thin copper layer was formed under the same conditions as in Example 11 except that the thickness of the ultra-thin copper layer was set to 2 μm.

˙Example 13

<Middle layer>

(1) Ni layer (Ni plating)

A Ni layer was formed under the same conditions as in Example 11.

(2) Organic layer (organic layer forming treatment)

Next, after the surface of the Ni layer formed in (1) was washed with water and pickled, the liquid temperature of the carboxybenzotriazole (CBTA) containing a concentration of 1 to 30 g / L was 40 ° C and the pH was set under the following conditions. The aqueous solution of 5 was spray-washed on the surface of the Ni layer for 20 to 120 seconds, thereby forming an organic layer.

<Ultra-thin copper layer>

An extremely thin copper layer is formed on the organic layer formed in (2). An ultra-thin copper layer was formed under the same conditions as in Example 11 except that the thickness of the ultra-thin copper layer was 3 μm.

˙Examples 14, 15

<Middle layer>

(1) Co-Mo layer (cobalt-molybdenum alloy plating)

The carrier was electroplated on a roll-to-roll continuous plating line under the following conditions to form a Co-Mo layer with an adhesion amount of 4000 μg / dm ² . The specific plating conditions are described below.

(Liquid composition) Co sulfate: 50 g / dm ³ , sodium molybdate dihydrate: 60 g / dm ³ , sodium citrate: 90 g / dm ³

(Liquid temperature) 30 ℃

(Current density) 1 ~ 4A / dm ²

(Power-on time) 3 ~ 25 seconds

<Ultra-thin copper layer>

An extremely thin copper layer is formed on the Co-Mo layer formed in (1). In Example 14, the thickness of the ultra-thin copper layer was set to 3 μm, and in Example 15, the thickness of the ultra-thin copper layer was set to 5 μm. Except that, the ultra-thin copper was formed under the same conditions as in Example 11. Floor.

Various samples of the examples and comparative examples produced as described above were subjected to various evaluations as described below.

<Measurement of adhesion amount>

For the measurement of the adhesion amount of various metals other than Cu in the surface treatment layer, a 50 mm × 50 mm copper foil surface film was dissolved in a solution mixed with HNO ₃ (2% by weight) and HCl (5% by weight), and ICP was used. An emission spectrum analysis device (manufactured by Seiko Instruments Nano Technology Co., Ltd., SFC-3100) quantifies the metal concentration in the solution, and deduces the amount of metal per unit area (μg / dm ² ). At this time, if necessary, the amount of metal deposited on the side opposite to the side to be measured will not be mixed, and if necessary, it will be masked for analysis. The measurement is performed on a sample that has been subjected to the above-mentioned Zn, Co, Ni, Fe, or an alloy plating thereof, a chromic acid treatment, and a silane coupling treatment. As for the measurement of the Cu adhesion amount of the surface treatment layer, it is the weight of the surface-treated copper foil with a size of 100 mm × 100 mm minus the above-mentioned measurement of the adhesion amount of various metals per unit area except for Cu per unit area and the surface treatment. The weight per unit area of the front copper foil was obtained.

<Measurement of surface roughness Rz>

Ten-point average roughness (Rz) was measured on the surface treated surface using a contact roughness meter SP-11 manufactured by Kosaka Research Co., Ltd. in accordance with JIS B0601-1994. Under the conditions of a measurement reference length of 0.8 mm, an evaluation length of 4 mm, a cutoff value of 0.25 mm, and a conveying speed of 0.1 mm / sec, the measurement position was changed 10 times, and the average value of the 10 measured values was set to the value of surface roughness Rz . In addition, for each of the electrolytic copper foil and the rolled copper foil used in the examples and comparative examples, the roughness Rz before the surface treatment was also measured. The measurement of the ten-point average roughness is performed with respect to the TD direction (the width direction of the copper foil (the direction perpendicular to the copper foil advancement direction in the copper foil manufacturing apparatus)).

<Measurement of Surface Area Ratio>

As for the three-dimensional surface area, a laser microscope LEXT OLS4000 (laser wavelength 405 nm, differential drying method) manufactured by Olympus Co., Ltd. was used for a region having a two-dimensional surface area of 66455 μm ^{2 in} the precipitation surface of the surface-treated copper foil. measuring. The surface area ratio was obtained by dividing the measured three-dimensional surface area by the two-dimensional surface area.

<Measurement of transmission loss>

Each sample with a thickness of 18 μm and a commercially available liquid crystal polymer resin (Kuraray Co., Ltd. Vecstar CTZ-50μm manufactured by the company after bonding, forming a microwave transmission line by etching so that the characteristic impedance becomes 50Ω, using a network analyzer HP8720C manufactured by HP to measure the penetration coefficient, and finding the frequency at 20GHz Transmission loss. As the evaluation of the transmission loss at a frequency of 20 GHz, it is set to ◎ for 5.0 dB / 10 cm or less, and ○ for 5.0 dB / 10 cm or more and 6.0 dB / 10 cm or less, and × for 6.0 dB / 10 cm or more. The size of the transmission loss is affected by the relative dielectric constant, dielectric loss tangent, and thickness of the resin used. Therefore, it will be used for copper foils used in general printed wiring boards (copper foils used in Comparative Example 2). Those who have a significant reduction in transmission loss are set as the above-mentioned determination criterion.

The test results are shown in Table 3.

(Evaluation results)

Regarding Examples 1 to 15, the total adhesion amounts of Co, Ni, and Fe in the surface treatment layer were all 1000 μg / dm ² or less. The surface treatment layers all had a Zn metal layer or an alloy treatment layer containing Zn, and the surface area ratios were all 1.0 to 1.9, the surface roughness Rz JIS are all 2.2 μm or less. Therefore, the transmission losses of Examples 1 to 15 were all well suppressed.

In Comparative Example 1, since the surface area ratio exceeds 1.9, the transmission loss is large.

In Comparative Example 2, since the surface roughness Rz JIS exceeds 2.2 μm and the surface area ratio exceeds 1.9, the transmission loss is large.

In Comparative Example 3, since the surface roughness Rz JIS exceeds 2.2 μm, the transmission loss is large.

Comparative Examples 4 to 6 Comparative Example 4 to 6 changed the plating treatment 3 of Example 7 to those containing Co, Ni, and Fe, and the total adhesion amount of Co, Ni, and Fe in the surface treatment layer exceeded 1000 μg / dm ² . The transmission loss of 6 is larger than that of Embodiment 7.

FIG. 1 is a graph showing the relationship between the total adhesion amount of Co, Ni, and Fe and the surface roughness Rz in Examples and Comparative Examples. FIG. 2 is a graph showing the relationship between the total adhesion amount of Co, Ni, and Fe and the ratio of the three-dimensional surface area to the two-dimensional surface area in the examples and comparative examples. FIG. 3 is a graph showing the relationship between the total adhesion amount of Co, Ni, Fe, Cu, and Zn and transmission loss in Examples and Comparative Examples.

Claims (25)

A surface-treated copper foil having a surface-treated layer formed on at least one surface thereof. The total adhesion amount of Co, Ni, and Fe in the surface-treated layer is 1000 μg / dm ² or less. The surface-treated layer has a Zn metal layer or an alloy containing Zn. Treatment layer, the surface of the surface treatment layer has a two-dimensional surface area of 66455 μm ² , and the ratio of the three-dimensional surface area to the two-dimensional surface area measured by a laser microscope is 1.0 to 1.9, and the surface roughness Rz JIS of at least one surface is 2.2 μm or less. For example, the surface-treated copper foil of the first patent application scope, wherein the total adhesion amount of Co, Ni, and Fe in the surface-treated layer is 500 μg / dm ² or less. For example, the surface-treated copper foil according to item 2 of the scope of patent application, wherein the total adhesion amount of Co, Ni, and Fe in the surface-treated layer is 300 μg / dm ² or less. For example, the surface-treated copper foil of item 3 of the scope of application for a patent, wherein the total adhesion amount of Co, Ni, and Fe in the surface-treated layer is 0 μg / dm ² . For example, the surface-treated copper foil of the first scope of the patent application, wherein the surface roughness Rz JIS of both surfaces is 2.2 μm or less. For example, the surface-treated copper foil according to item 1 of the patent application scope, wherein the surface-treated layer includes a roughened layer. For example, the surface-treated copper foil of item 6 of the patent application scope, wherein the amount of Cu deposited in the roughened layer is 0.10 g / dm ² or less. For example, the surface-treated copper foil according to item 6 of the scope of patent application, wherein the surface-treated layer is provided with the Zn metal layer or an alloy-treated layer containing Zn on the roughened layer. For example, the surface-treated copper foil of the scope of application for patent No. 1, wherein the alloy containing Zn is treated The layer is a Cu-Zn alloy layer. For example, the surface-treated copper foil of item 1 of the patent application scope, wherein the Zn adhesion amount in the surface-treated layer is 5 mg / dm ² or less. For example, the surface-treated copper foil according to item 1 of the application, wherein a chromate treatment layer is provided on the Zn metal layer or an Zn-containing alloy treatment layer in the surface treatment layer. For example, the surface-treated copper foil according to item 11 of the application, wherein a silane coupling treatment layer is provided on the chromic acid treatment layer. For example, the surface-treated copper foil in the first scope of the patent application, wherein the total adhesion amount of Cu, Zn, Co, Ni, and Fe in the surface-treated layer is 0.10 g / dm ² or less. For example, the surface-treated copper foil according to any one of claims 1 to 13 is used for flexible printed wiring boards. For example, the surface-treated copper foil according to any one of claims 1 to 13 is used for high-frequency circuit substrates above 5 GHz. A laminated board is manufactured by laminating a surface-treated copper foil and a resin substrate in any one of the scope of application for patents 1 to 13. A printed wiring board is made of a laminated board with the scope of patent application No. 16 as a material. An electronic device using a printed wiring board having the scope of application for item 17 of the patent. A copper foil with a carrier is provided on one or both sides of the carrier with an intermediate layer and an ultra-thin copper layer in order. The ultra-thin copper layer is a surface-treated copper foil according to any one of claims 1 to 13. For example, the copper foil with a carrier of the scope of application for item 19 has the intermediate layer, the ultra-thin copper layer in order on one side of the carrier, and a roughening layer on the other side of the carrier. A laminated board is manufactured by laminating a copper foil with a carrier and a resin substrate in the scope of patent application No. 19 or 20. A printed wiring board is manufactured by using a laminated board with the scope of patent application No. 21. An electronic device using a printed wiring board having a scope of application for patent No. 22. A method for manufacturing a printed wiring board includes the following steps: a step of preparing a copper foil with a carrier and an insulating substrate for applying for a patent application No. 19 or 20; a step of laminating the copper foil with a carrier and an insulating substrate; After the foil and the insulating substrate are laminated, a metal-clad laminated board is formed through a step of peeling the carrier of the copper foil with the carrier, and then, by a semi-additive process, a subtractive process, a part A step of forming a circuit by a partially additive process or a modified semi-additive process. A method for manufacturing a printed wiring board includes the steps of: forming a circuit on the ultra-thin copper layer side surface of the copper foil with a carrier or on the carrier side surface of a copper foil with a carrier in the scope of application for a patent; A step of forming a resin layer on the ultra-thin copper layer side surface of the copper foil with a carrier or the carrier side surface; a step of forming a circuit on the resin layer; after forming a circuit on the resin layer, the carrier or the A step of peeling the ultra-thin copper layer; and removing the carrier or the ultra-thin copper layer, removing the ultra-thin copper layer or the carrier, thereby forming the side surface of the ultra-thin copper layer or the side surface of the carrier The step of exposing the buried circuit of the resin layer.