Copper member

Abstract

To provide a copper member with excellent handleability, in which it can be appropriately peeled when peeling is needed, and it cannot be easily peeled when peeling is not needed.SOLUTION: A copper member includes protrusions formed on a copper material and on part of or all of the surface of the copper material, in which the copper material and the protrusions are peelably formed. The protrusion includes copper and / or a copper oxide. The copper member has a 90-degree peel strength of 120 gf / cm or lower when it is crimped with a resin substrate and peeled apart.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to copper components. [Background technology]

[0002] In recent years, there has been an increasing demand for finer wiring in printed circuit boards such as printed wiring boards and semiconductor package substrates. Known methods for forming circuits on these boards include subtractive methods, semi-additive methods such as the SAP (Semi-Additive Process) and M-SAP (Modified Semi-Additive Process) (Patent Document 1), and full-additive methods.

[0003] The subtractive method involves preparing a laminate of a resin substrate and copper foil, covering the necessary areas of the copper foil (where the wiring is to be formed) with resist, and then etching the copper foil. After etching, the resist on the copper foil is removed, leaving the copper foil in the areas covered with resist, which becomes the copper wiring. The subtractive method has the problem of resulting in thin wiring because the copper in the wiring area is also affected when etching the copper foil (a phenomenon known as over-etching). While thinning the copper foil and shortening the etching time are effective ways to reduce this effect, thinning the copper foil tends to cause breaks, creases, and wrinkles during the laminate formation process and the preparation stage for this process, making it difficult to handle the copper foil alone. Therefore, the copper foil thickness is limited to approximately 9 μm.

[0004] The semi-additive method is a construction method that overcomes the drawbacks of the subtractive method. In the semi-additive method, a resin substrate with a metal seed layer on its surface is coated with a resist on the areas where wiring will not be made, and then plated. After removing the resist, the remaining seed layer is etched to form fine circuits. Known semi-additive methods include the SAP method and the M-SAP method. In the SAP method, a seed layer is formed on the surface of the resin substrate by electroless plating. In the M-SAP method, a resin substrate with copper foil attached is used as the seed layer.

[0005] The semi-additive method (particularly the M-SAP method) solves the problems of breakage, creases, and wrinkles that occur when copper foil is thinned by using a material (carrier-attached copper foil) in which an ultra-thin copper foil with a thickness of 6 μm or less is bonded to a carrier layer via a release layer. Therefore, although unnecessary copper foil portions must be dissolved and removed by etching, the thinness of the copper foil reduces the impact of over-etching, resulting in higher wiring accuracy than the subtractive method. An example of a material used in this method is carrier-attached copper foil, as described in Patent Document 1. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2001-089892 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the carrier-attached copper foil described above has the characteristic that the copper foil easily peels from the carrier layer, which can lead to problems such as unintended peeling. For example, when laminating the carrier-attached copper foil with a resin substrate, unintended contact between the copper foil and parts of the equipment during the lamination operation can lead to peeling, breakage, or wrinkles of the copper foil from the carrier layer. Furthermore, for example, peeling easily occurs even when the copper foil touches an unintended portion of the resin substrate, making it difficult to obtain the intended seed layer. When the copper foil peels from the carrier-attached copper foil, (1) resin components in the resin substrate may infiltrate the peel layer from the peeled portion (damaged portion) and cover the copper foil, potentially impairing the function of the covered portion as a seed layer. Furthermore, (2) adhesion between the resin components and the carrier layer can cause damage to the surface of the resin substrate during copper foil peeling, potentially resulting in problems such as loss of flatness. These problems can lead to short circuits, disconnections, and other problems in the formed wiring circuits during the manufacturing process of printed wiring boards. Therefore, from the above perspectives, the carrier-attached copper foil described above cannot be said to have sufficient handleability.

[0008] Therefore, an object of the present invention is to provide a copper member that is easy to handle in that it peels appropriately when peeling is required and is less likely to peel in unintended situations. [Means for solving the problem]

[0009] As a result of extensive research into achieving the above object, the inventors have found that the above problems can be solved by using a copper member having a specific structure. The present invention was completed based on these findings.

[0010] That is, in the present invention, there is provided a copper member including a copper material and protrusions formed on a part or all of the surface of the copper material, the copper material and the protrusions being formed so as to be separable from each other, the protrusions contain copper and / or copper oxide; Provided is a copper member that has a 90° peel strength of 120 gf / cm or less when pressed against a resin substrate and then peeled off.

[0011] the copper member includes a copper oxide layer; It is preferable that the copper oxide layer has the protrusions as a part or the whole of the copper oxide layer.

[0012] the copper member includes a metal layer other than copper, It is preferable that the metal layer other than copper is formed so as to cover a part or the whole of the surface of the copper oxide layer.

[0013] The height (average height) of the protrusions is preferably 30 nm or more.

[0014] The thickness of the copper oxide layer is preferably 500 nm or less.

[0015] In a resin substrate with a seed layer obtained by thermocompression bonding a resin substrate to the surface of the copper member on which the protrusions are formed to form a laminate, and then peeling the copper member from the resin substrate in the laminate, it is preferable that the thickness of the seed layer be 30 nm or more.

[0016] The copper member is preferably rated as category 0 in a cross-cut adhesion test in accordance with JIS K-5600-5-6:1999.

[0017] The present invention also provides a laminate in which the copper member and a resin base material are laminated together so that the resin base material and protrusions formed on the surface of the copper member abut against each other.

[0018] The resin substrate preferably contains at least one insulating resin selected from the group consisting of polyphenylene ether (PPE), epoxy, polyphenylene oxide (PPO), polybenzoxazole (PBO), polytetrafluoroethylene (PTFE), liquid crystal polymer (LCP), thermoplastic polyimide (TPI), fluororesin, polyetherimide, polyetheretherketone, polycycloolefin, bismaleimide resin, low dielectric constant polyimide, and cyanate resin.

[0019] The present invention also provides a method for producing a printed circuit board including a resin substrate and a wiring pattern formed on a surface of the resin substrate, the method comprising: forming protrusions containing copper and / or copper oxide on a part or all of the surface of a copper material; a step of treating the copper material with a release agent to obtain the copper member; a step of laminating a resin base material and the copper member such that the resin base material and the protrusions formed on the surface of the copper member abut against each other to form a laminate; a step of separating the resin substrate from the copper member and transferring protrusions formed on the surface of the copper member to the resin substrate, thereby forming a seed layer containing copper and / or copper oxide on the surface of the resin substrate; a step of plating the surface of the resin substrate using a plating solution; The present invention provides a method for manufacturing a printed circuit board, comprising:

[0020] The method for manufacturing the printed circuit board preferably includes a step of plating the surface of the copper member using a plating solution between the step of treating the copper material with a release agent and the step of forming the laminate.

[0021] In the method for manufacturing a printed circuit board, the step of forming the protrusions includes: It is preferable that the step be a step of forming protrusions containing copper oxide by oxidation treatment.

[0022] In the method for producing a printed circuit board, the oxidation treatment is preferably carried out using an oxidizing agent.

[0023] In the method for producing a printed circuit board, in the step of plating the surface of the resin base material with a plating solution, the plating is preferably an electroless plating treatment.

[0024] In the method for producing a printed circuit board, in the step of plating the surface of the resin base material with a plating solution, the plating is preferably an electroless plating treatment using Cu.

[0025] The present invention also provides a method for producing a resin substrate with a seed layer, the method comprising: a resin substrate; and a seed layer containing copper and / or copper oxide formed on a surface of the resin substrate, the method comprising: forming protrusions containing copper and / or copper oxide on a part or all of the surface of a copper material; a step of treating the copper material with a release agent to obtain the copper member; a step of laminating a resin base material and the copper member such that the resin base material and the protrusions formed on the surface of the copper member abut against each other to form a laminate; a step of separating the resin substrate from the copper member and transferring protrusions formed on the surface of the copper member to the resin substrate, thereby forming a seed layer containing copper and / or copper oxide on the surface of the resin substrate; The present invention provides a method for producing a resin substrate with a seed layer, comprising the steps of:

[0026] The method for producing the resin substrate with a seed layer preferably includes a step of plating the surface of the copper member using a plating solution between the step of treating the copper material with a release agent and the step of forming the laminate.

[0027] In addition, the present invention provides a method for manufacturing a copper substrate, comprising the steps of: forming protrusions containing copper and / or copper oxide on a part or all of a surface of a copper material; treating the copper material with a release agent; The present invention provides a method for producing the copper member, comprising:

[0028] The method for producing the copper member preferably includes a step of plating the surface of the copper member with a plating solution after the step of treating the copper material with a stripping improver. [Effects of the Invention]

[0029] The copper member of the present invention has excellent handleability. [Brief explanation of the drawings]

[0030] [Figure 1] 1 is a schematic cross-sectional view showing one embodiment of a copper member of the present invention. [Figure 2] 1 is a schematic cross-sectional view showing one embodiment of a laminate of the present invention. [Figure 3] 1 is a schematic diagram of a seed layer in a seed layer-attached resin substrate of the present invention. [Figure 4] FIG. 1 is a schematic diagram illustrating a printed circuit board on which electronic components are mounted. [Figure 5] 10A and 10B are diagrams illustrating a method for measuring / calculating the height of a protrusion. DETAILED DESCRIPTION OF THE INVENTION

[0031] One embodiment of the present invention (hereinafter referred to as embodiment 1) is a copper member. The copper member includes a copper material and protrusions formed on a part or all of a surface of the copper material, and the copper material and the protrusions are formed so as to be separable from each other, the protrusions contain copper and / or copper oxide; It is characterized by having a 90° peel strength of 120 gf / cm or less when pressed against a resin substrate and then peeled off.

[0032] More specifically, the 90° peel strength of the copper member is measured by the following method. (90° peel strength measurement method) A copper member and a resin substrate, R-1551 (manufactured by Panasonic Industries Co., Ltd.), were laminated so that the protrusions formed on the surface of the copper member abutted the resin substrate. The laminate was heated to 130°C and pressed under 1.2 MPa. After reaching 130°C, the temperature was maintained at 130°C for 10 minutes. The laminate was then heated to 190°C under a pressure of 2.3 MPa and maintained at 190°C for 50 minutes, completing the thermocompression bonding. The vacuum level was 2 kPa or less. The resulting sample (a laminate of a copper member and a resin substrate) was subjected to a 90° peel test (Japanese Industrial Standard (JIS) C5016) to measure the peel strength (gf / cm) when the copper member was peeled from the resin substrate in a 90° direction at a rate of 50 mm / min. The measurement width of the measurement sample was 10 mm.

[0033] The 90° peel strength of the copper member is the peel strength when the copper member is peeled from the resin substrate as described above, but it can also be explained as the peel strength when the copper material and the protrusions are peeled off. That is, when the copper member is peeled off from the resin substrate, the protrusions formed on the surface of the copper material are transferred to the surface of the resin substrate as a seed layer, and the protrusions peel off from the surface of the copper material. The 90° peel strength of the copper member can be explained as the peel strength in this phenomenon.

[0034] Another embodiment of the present invention (hereinafter referred to as embodiment 2) is a laminate. The laminate is a laminate of the copper member according to embodiment 1 and a resin base material. That is, the laminate is a laminate in which the copper member and the resin base material are laminated such that the resin base material and the protrusions formed on the surface of the copper member abut against each other.

[0035] Yet another embodiment of the present invention (hereinafter referred to as embodiment 3) is a method for producing a printed circuit board. The printed circuit board includes a resin base material and a wiring pattern formed on the surface of the resin base material. The method includes at least the following steps: a protrusion forming step, a peelability improving step, a laminate forming step, a laminate separating step, and a resin substrate plating step, which will be described later. The method may also include a copper material plating step. A step of forming protrusions containing copper and / or copper oxide on a part or all of the surface of the copper material (protrusion forming step) A step of treating the copper material with a release agent (release improving step) A step of plating the surface of the copper material using a plating solution (copper material plating step). A step of laminating a resin base material and the copper member so that the resin base material and the protrusions formed on the surface of the copper member come into contact with each other to form a laminate (laminate formation step). A step of separating the resin substrate from the copper member and transferring the protrusions formed on the surface of the copper member to the resin substrate, thereby forming a seed layer containing copper and / or copper oxide on the surface of the resin substrate (laminate separation step). A step of plating the surface of the resin substrate using a plating solution (resin substrate plating step).

[0036] Another embodiment of the present invention (hereinafter referred to as embodiment 4) is a method for producing a resin substrate with a seed layer, comprising a resin substrate and a seed layer containing copper and / or copper oxide formed on the surface of the resin substrate. The method includes at least a protrusion forming step, a releasability improving step, a laminate forming step, and a laminate separating step, and may further include a copper material plating step.

[0037] Yet another embodiment of the present invention (hereinafter referred to as embodiment 5) is a method for producing the copper member of embodiment 1. The method includes at least a protrusion forming step and a releasability improving step, and may further include a copper plating step.

[0038] Yet another embodiment of the present invention (hereinafter referred to as embodiment 6) is a method for producing the laminate of embodiment 2. The method includes at least a protrusion forming step, a releasability improving step, and a laminate forming step, and may further include a copper material plating step.

[0039] Hereinafter, there will be described a copper member according to embodiment 1 and a laminate according to embodiment 2. In this specification, the copper member according to embodiment 1 may be referred to as the "copper member of the present invention."

[0040] [Copper material] The copper member of the present invention includes a copper material and protrusions formed on a part or all of the surface of the copper material, and the copper material and the protrusions are formed so as to be separable from each other, the protrusions contain copper and / or copper oxide; It is characterized by having a 90° peel strength of 120 gf / cm or less when pressed against a resin substrate and then peeled off.

[0041] The copper member of the present invention has a structure different from that of conventional carrier-attached copper foils used in semi-additive processes. Specifically, the above-mentioned conventional carrier-attached copper foils have a three-layer structure in which a carrier foil, a release layer, and an ultra-thin copper foil are laminated in this order. On the other hand, the copper member does not have a release layer, and therefore its structure is clearly different from that of conventional carrier-attached copper foils. That is, the copper member has a structure different from that of conventional carrier-attached copper foils in that protrusions are formed on the surface of the copper material, and the copper material and the protrusions are formed so as to be peelable from each other.

[0042] The 90° peel strength is not particularly limited as long as it is 120 gf / cm or less, but is preferably 100 gf / cm or less, more preferably 80 gf / cm or less, even more preferably 60 gf / cm or less, and particularly preferably 40 gf / cm or less. When the 90° peel strength is within the above range, the protrusions formed on the surface of the copper material tend to peel along the surface and transfer to the resin substrate more easily.

[0043] The copper member of the present invention achieves a test result of Class 0 in a cross-cut adhesion test in accordance with JIS K-5600-5-6:1999. That is, it has excellent handleability in that peeling is unlikely to occur in unintended situations. More specifically, the cross-cut adhesion test can be carried out using the test method used in the examples described below.

[0044] The copper member of the present invention may include a copper oxide layer. More specifically, a copper oxide layer may be formed on the surface of the copper material. When a copper oxide layer is formed on the surface of the copper material, the protrusions are formed on the surface of the copper material as part or all of the copper oxide layer. Such an embodiment can be realized, for example, by a protrusion forming step.

[0045] In the copper member, protrusions are formed on the surface of the copper material, and the copper material and the protrusions are formed so as to be separable from each other. This embodiment can be obtained, for example, through the process described in the "Separability Improvement Process." Specifically, by treating a copper material on which protrusions containing copper and / or copper oxide are formed with a release property improver, the copper material and the protrusions become separable from each other. This means that the copper material and the protrusions are connected via a surface that allows them to be separated (referred to as the "surface of the copper material" in this specification). In other words, it can be explained that treating the copper material with the release property improver forms a surface that allows the copper material and the protrusions to be separated from each other. Because the copper member has this embodiment, when the resin substrate and the copper member are separated from each other in the laminate formed through the "laminate formation process" described below, the protrusions formed on the surface of the copper member peel along the surface and are transferred to the resin substrate.

[0046] The copper member may include a metal layer other than copper. More specifically, a metal layer other than copper may be formed so as to cover a part or all of the surface of the protrusion. When a copper oxide layer is formed on the surface of the copper material, a metal layer other than copper may be formed so as to cover a part or all of the surface of the copper oxide layer. Such an embodiment can be realized, for example, by a "copper material plating treatment step."

[0047] (copper material) In the copper member of the present invention, the copper material refers to a material whose surface is partially or entirely made of copper. The material inside the copper material (inside the copper present on the surface) may be copper or a material other than copper (for example, a metal other than copper, a resin substrate, etc.), but is preferably copper. In other words, the copper material is preferably a material made entirely of copper.

[0048] When the interior of the copper material is made of a substance other than copper, the thickness of the copper on the surface is not particularly limited, but is preferably 1 nm or more, more preferably 10 nm or more, and even more preferably 100 nm or more, for example. In this case, the copper on the surface of the copper material may be formed by plating using a copper plating solution.

[0049] The purity of the copper on the surface of the copper material is preferably, for example, 95% by mass or more, 99% by mass or more, or 99.9% by mass or more of pure copper. Even when the copper material is entirely made of copper, the purity of the copper is preferably within the above range. Examples of such copper include tough pitch copper, deoxidized copper, and oxygen-free copper. Among these, oxygen-free copper with an oxygen content of 0.001 to 0.0005% by mass is preferred.

[0050] Examples of the copper material include copper foils such as electrolytic copper foil, rolled copper foil, and copper foil with a carrier, and copper plates. Here, copper foil refers to a material having a thickness of 100 μm or less, and copper plates refers to a material having a thickness of more than 100 μm. The thickness of the copper foil is preferably, for example, 0.1 μm or more, more preferably 0.5 μm or more, and even more preferably 1 μm or more. It is also preferably 80 μm or less, more preferably 50 μm or less. The thickness of the copper plate is, for example, preferably 0.3 mm or more, more preferably 0.5 mm or more, even more preferably 1 mm or more, and particularly preferably 5 mm or more. It is also preferably 5 cm or less, more preferably 3 cm or less, and even more preferably 1 cm or less.

[0051] The protrusions formed on the surface of the copper material are not particularly limited as long as they contain copper and / or copper oxide, but preferably contain copper oxide. Examples of methods for forming copper-containing protrusions on the surface of a copper material include plating treatment using a copper plating solution. Examples of methods for forming copper oxide-containing protrusions on the surface of a copper material include oxidation treatment. When copper oxide-containing protrusions are formed by oxidation treatment, a copper oxide layer, which will be described later, is formed on the surface of the copper material.

[0052] The height (average height) of the protrusions is not particularly limited, but is preferably 30 nm or more, more preferably 50 nm or more, even more preferably 80 nm or more, and particularly preferably 120 nm or more. Also, for example, it is preferably 500 nm or less, more preferably 400 nm or less, even more preferably 300 nm or less, particularly preferably 250 nm or less, and most preferably 200 nm or less. The height of the protrusions can be measured, for example, by calculating the average height of the protrusions, taking the distance between the midpoint of a line segment connecting the minimum points of adjacent recesses at a predetermined interval across the protrusions, and the maximum point of the protrusion between the recesses.

[0053] The average height of the protrusions can be determined by, for example, using a FIB-SEM (AURIGA, manufactured by Carl Zeiss K.K.) to expose a cross section perpendicular to the copper member, capturing a cross-sectional image at an acceleration voltage of 2 kV and a magnification of 30,000x. In the obtained cross-sectional image, the protrusion height is measured by measuring the distance between the midpoint of the line segment connecting the minimum points of adjacent concave portions across the convex portion and the maximum point of the convex portion between the concave portions. The average height of the protrusions can be calculated by measuring the height of five protrusions in a similar manner and calculating the average. The five protrusions can be obtained by dividing the obtained cross-sectional image into six equal parts horizontally at equal distances and selecting the protrusion closest to the dividing line. Referring to Figure 5, 41 represents the copper member, 42 represents the protrusion, and L (white line) represents the protrusion height.

[0054] In a scanning electron microscope (SEM) image obtained by observing a cross section perpendicular to the surface of a copper member using a focused ion beam (FIB), the number of protrusions 50 nm or more in height per any 3.8 μm is not particularly limited, but is preferably 10 or more, more preferably 13 or more, even more preferably 16 or more, and particularly preferably 18 or more. Also, for example, it is preferably 60 or less, more preferably 50 or less, even more preferably 45 or less, and particularly preferably 40 or less. The magnification of the SEM observation is 30,000 times.

[0055] (copper oxide layer) The copper member of the present invention may have a copper oxide layer formed on the surface of a copper material. That is, the copper member may include a copper material and a copper oxide layer formed on the surface of the copper material. The copper oxide layer is a portion that is transferred from the surface of the copper member to the resin substrate in the laminate separation step, and constitutes a "seed layer containing copper and / or copper oxide" on the surface of the resin substrate by the same step.

[0056] Examples of copper oxides in the copper oxide layer include copper oxide (CuO) and cuprous oxide (CuO), and either or both may be contained in the copper oxide layer. The copper oxide layer may also contain copper. The copper oxide content in the copper oxide layer is not particularly limited, but may be, for example, 0.1% by mass or more, 0.3% by mass or more, 0.5% by mass or more, 1% by mass or more, 3% by mass or more, 5% by mass or more, or 10% by mass or more. The copper oxide layer may also contain copper hydroxide (Cu(OH)), and the content thereof may be, for example, 0.01% by mass or more, 0.03% by mass or more, 0.05% by mass or more, 0.1% by mass or more, 0.5% by mass or more, 1% by mass or more, 3% by mass or more, or 5% by mass or more.

[0057] The thickness of the copper oxide layer is preferably 500 nm or less, more preferably 300 nm or less, even more preferably 200 nm or less, particularly preferably 160 nm or less, and most preferably 90 nm or less. Furthermore, the thickness of the copper oxide layer is preferably 20 nm or more, more preferably 30 nm or more, and even more preferably 40 nm or more. The thickness of the copper oxide layer refers to the thickness measured, for example, by SERA measurement, converted into a uniform thickness. More specifically, the test methods used in the examples described below can be mentioned.

[0058] The method for forming the copper oxide layer is not particularly limited, but examples thereof include a method of subjecting a copper material to an oxidation treatment using an oxidizing agent, and a method of subjecting the copper material after the oxidation treatment to a reduction treatment using a reducing agent.

[0059] (metal layer other than copper) In the copper member of the present invention, a metal layer other than copper may be formed on part or all of the surface of the copper material so as to cover the protrusions formed on the surface of the copper material. When a copper oxide layer is formed on the surface of the copper material, a metal layer other than copper may be formed so as to cover part or all of the surface of the copper oxide layer. The formation of a copper oxide layer on the surface of the copper material tends to exhibit appropriate adhesion and improve reliability (e.g., heat resistance and chemical resistance). The metal other than copper can be identified, for example, by energy dispersive X-ray analysis (EDX) using a transmission electron microscope (TEM) on the surface and / or cross section of the metal layer.

[0060] The non-copper metal layer refers to a layer containing a metal other than copper, such as Ni, Co, Fe, Gd, Zn, Cr, Mo, Ti, Al, or Mn.

[0061] The metal layer other than copper is formed, for example, by plating the surface of the copper material or copper oxide layer using a plating solution. The plating solution is not particularly limited as long as it contains a metal other than copper. The plating method is not particularly limited, and plating can be performed by electrolytic plating, electroless plating, vacuum deposition, chemical conversion treatment, etc., but electrolytic plating is preferred because it is preferable to form a uniform plating layer. The plating method and materials used (e.g., plating solution) can be, for example, those described in the "Copper Material Plating Treatment Process" below.

[0062] The thickness (equivalent to a planar surface) of the metal layer other than copper is not particularly limited, but is preferably 1 to 190 nm, more preferably 5 to 160 nm, even more preferably 10 to 120 nm, particularly preferably 20 to 100 nm, and most preferably 25 to 80 nm. When the thickness of the metal layer is within the above range, the metal layer tends to be uniformly distributed, resulting in better adhesion to the resin substrate. The thickness (equivalent to a planar surface) of the metal layer other than copper can be calculated using the method described in the "Plating Thickness (equivalent to a planar surface)" section of the Examples below.

[0063] [Laminate] The laminate of the present invention is characterized in that it is obtained by laminating the copper member and a resin substrate. The resin substrate may be at least one insulating resin selected from the group consisting of polyphenylene ether (PPE), epoxy, polyphenylene oxide (PPO), polybenzoxazole (PBO), polytetrafluoroethylene (PTFE), liquid crystal polymer (LCP), thermoplastic polyimide (TPI), fluororesin, polyetherimide, polyetheretherketone, polycycloolefin, bismaleimide resin, low dielectric constant polyimide, and cyanate resin.

[0064] The thickness of the resin substrate is not particularly limited, but is preferably 0.1 to 100 μm, more preferably 0.5 to 80 μm, and even more preferably 1 to 60 μm. The resin substrate may further contain an inorganic filler or glass fiber. The relative dielectric constant of the resin substrate is preferably 5.0 or less, more preferably 4.0 or less, and even more preferably 3.8 or less.

[0065] FIG. 1 is a schematic cross-sectional view showing one embodiment of the copper member of the present invention. 1 is the copper member, 2 is a copper material, 3 is a copper oxide layer, 4 is a protrusion, and 5 is a metal layer other than copper. The copper material 2 and the protrusion 4 are connected via a surface (the surface of the copper material) that allows them to be peeled off. The copper material 2 and the protrusion 4 on the surface of the copper material may be connected entirely or partially. The protrusion 4 is part of the copper oxide layer 3 and contains copper oxide. The metal layer 5 is formed on the surface of the copper oxide layer 3. FIG. 2 is a schematic cross-sectional view showing one embodiment of the laminate of the present invention. 10 is the laminate, 11 is the copper member, and 12 is a resin substrate.

[0066] Below, we will explain the method for manufacturing a printed circuit board according to embodiment 3 of the present invention, the method for manufacturing a resin substrate with a seed layer according to embodiment 4, the method for manufacturing a copper component according to embodiment 5, and the method for manufacturing a laminate according to embodiment 6.

[0067] The method for producing a printed circuit board according to the third embodiment of the present invention includes at least a protrusion forming step, a peelability improving step, a laminate forming step, a laminate separating step, and a resin substrate plating step. In addition, a copper material plating step may be further included between the peelability improving step and the laminate forming step.

[0068] The method for producing a resin substrate with a seed layer according to embodiment 4 includes at least a protrusion-forming step, a releasability-improving step, a laminate-forming step, and a laminate-separating step. The method may further include a copper plating step between the releasability-improving step and the laminate-forming step.

[0069] The method for producing a copper member according to embodiment 5 includes at least a protrusion forming step and a releasability improving step, and may further include a copper material plating step after the releasability improving step.

[0070] The method for producing a laminate according to the sixth embodiment includes at least a protrusion forming step, a releasability improving step, and a laminate forming step. In addition, a copper plating step may be further included between the releasability improving step and the laminate forming step.

[0071] (Protrusion formation process) The protrusion-forming step is a step of forming protrusions containing copper and / or copper oxide on the surface of a copper material. The method for forming the protrusions is not particularly limited. For example, protrusions containing copper can be formed by forming particles of copper or a copper alloy through a plating process. Furthermore, protrusions containing copper oxide can be formed by subjecting the surface of a copper material to an oxidation process. In this way, forming protrusions on the surface of a copper material through a copper plating process or an oxidation process tends to further improve adhesion to a resin substrate. Furthermore, the handleability of the copper member tends to improve, in that it can be appropriately peeled off when peeling is required.

[0072] In this step, before the copper plating treatment or oxidation treatment, a surface roughening treatment such as soft etching or etching, a degreasing treatment, an acid washing treatment to remove a natural oxide film from the copper material, an alkali treatment after the acid washing treatment, etc. The alkali treatment is not particularly limited, but examples include a method of treating with a 0.1 to 10 g / L or 1 to 2 g / L alkaline aqueous solution (e.g., sodium hydroxide aqueous solution) at 30 to 50°C for about 0.5 to 2 minutes.

[0073] The method of oxidation treatment is not particularly limited, and examples thereof include a method using an oxidizing agent, a method using thermal oxidation, and a method using electrolytic oxidation. Among these, a method using an oxidizing agent is preferred from the viewpoint of improving adhesion to a resin substrate.

[0074] The oxidizing agent is not particularly limited, but an aqueous solution of a chlorate such as sodium chlorite, sodium hypochlorite, potassium chlorate, or potassium perchlorate is preferably used. The oxidizing agent may contain additives such as a phosphate such as trisodium phosphate dodecahydrate, or a surface-active molecule. The surface-active molecule is used to adjust the size of the formed protrusions, and examples thereof include porphyrin, porphyrin macrocycle, expanded porphyrin, ring-contracted porphyrin, linear porphyrin polymer, porphyrin sandwich coordination complex, porphyrin array, silane, tetraorgano-silane, aminoethyl-aminopropyltrimethoxysilane, (3-aminopropyl)trimethoxysilane, (1-[3-(trimethoxysilyl)propyl]urea), (3-aminopropyl)triethoxysilane, ((3-glycidyloxypropyl)trimethoxysilane, Examples of the oxidizing agent include (3-chloropropyl)trimethoxysilane, (3-glycidyloxypropyl)trimethoxysilane, dimethyldichlorosilane, 3-(trimethoxysilyl)propyl methacrylate, ethyltriacetoxysilane, triethoxy(isobutyl)silane, triethoxy(octyl)silane, tris(2-methoxyethoxy)(vinyl)silane, chlorotrimethylsilane, methyltrichlorosilane, silicon tetrachloride, tetraethoxysilane, phenyltrimethoxysilane, chlorotriethoxysilane, ethylene-trimethoxysilane, amines, and sugars. The above oxidizing agents may be used singly or in combination of two or more.

[0075] When oxidation treatment is performed using an oxidizing agent, the treatment temperature is not particularly limited, but is preferably, for example, 30 to 95°C, more preferably 35 to 80°C, and even more preferably 45 to 60°C. The treatment time is not particularly limited, but is preferably, for example, 0.2 to 20 minutes, and more preferably 0.4 to 10 minutes. The concentration of the components contained in the oxidizing agent (e.g., the concentration of the chlorate) is not particularly limited, but is, for example, preferably 5 to 400 g / L, more preferably 20 to 350 g / L, and even more preferably 50 to 300 g / L. When the treatment temperature, treatment time, and oxidizing agent concentration are within the above ranges, the crystallinity of the resulting copper oxide layer is improved, and the 90° peel strength falls within an appropriate range, which tends to improve the handleability of the copper member.

[0076] After the oxidation treatment, the surface of the copper material may be reduced with a reducing agent. The reduction treatment may result in the formation of cuprous oxide (copper(I) oxide) on the surface of the copper material. The reducing agent is not particularly limited, but examples thereof include aqueous solutions of boron compounds such as dimethylamine borane (DMAB), diborane, sodium borohydride, and hydrazine.

[0077] The size, thickness, height, length, etc. of the copper oxide-containing protrusions may be adjusted by chelating the surface of the copper material using a chelating agent (particularly a biodegradable chelating agent). The chelating agent is not particularly limited, but examples include solutions of ethylenediaminetetraacetic acid, diethanolglycine, tetrasodium L-glutamate diacetate, ethylenediamine-N,N'-disuccinic acid, sodium 3-hydroxy-2,2'-iminodisuccinate, trisodium methylglycine diacetate, tetrasodium aspartate diacetate, disodium N-(2-hydroxyethyl)iminodiacetate, and sodium gluconate. The pH of the chelating agent is not particularly limited, but is preferably alkaline, more preferably pH 8 to 10.5, even more preferably pH 9.0 to 10.5, and even more preferably pH 9.8 to 10.2. The chelating agents may be used singly or in combination of two or more.

[0078] (Releasability improvement process) The releasability improving step is a step of treating the copper material with a releasability improving agent after the protrusion forming step. This treatment is a treatment for facilitating the separation of the surface layer portion of the copper material including the protrusions from the copper material. In other words, the releasability improving agent can be said to have the properties of facilitating the separation of the surface layer portion of the copper material including the protrusions from the copper material.

[0079] The release property improver is not particularly limited, and examples thereof include aqueous solutions of chlorides (nickel chloride, zinc chloride, iron chloride, chromium chloride, tin(II) chloride, etc.), ammonium salts (ammonium citrate, ammonium chloride, ammonium sulfate, ammonium nickel sulfate, etc.), chelating agents (ethylenediaminetetraacetic acid, diethanolglycine, tetrasodium L-glutamate diacetate, ethylenediamine-N,N'-disuccinic acid, sodium 3-hydroxy-2,2'-iminodisuccinate, trisodium methylglycine diacetate, tetrasodium aspartate diacetate, disodium N-(2-hydroxyethyl)iminodiacetate, sodium gluconate, etc.), and citric acid.

[0080] The treatment temperature in this step is not particularly limited, but is preferably 20 to 90°C, more preferably 30 to 80°C, and even more preferably 40 to 55°C. The treatment time is not particularly limited, but is preferably 0.2 to 20 minutes, more preferably 0.4 to 10 minutes, and even more preferably 1 to 8 minutes. The concentration of the release improver is not particularly limited, but is preferably 3 to 100 g / L, more preferably 5 to 80 g / L, even more preferably 12 to 60 g / L, and particularly preferably 15 to 50 g / L. When the treatment temperature, treatment time, and release improver concentration are within the above ranges, the 90° peel strength of the copper member falls within an appropriate range, and handling tends to be more excellent. This tendency is particularly pronounced when the release improver is nickel chloride, which tends to make it easier to achieve the 90° peel strength of the copper member within the desired range.

[0081] (Copper material plating process) The plating process involves plating the surface of a copper material using a plating solution, which can form a metal layer other than copper. The plating method is not particularly limited, and examples include electrolytic plating, electroless plating, vacuum deposition, and chemical conversion treatment. However, electrolytic plating is preferred from the perspective of uniformly forming a plating layer. This process tends to improve the heat resistance and chemical resistance of the seed layer-attached resin substrate and printed circuit board obtained through the laminate separation process described below. This process is performed separately from the release property improvement process. The plating process in this process and the treatment using a release property improver in the release property improvement process significantly affect the 90° peel strength of the resulting copper member, so the treatment temperature and treatment time must be strictly controlled. Therefore, performing these processes (treatments) simultaneously is undesirable because the treatment temperature and treatment time cannot be individually adjusted, making it difficult to impart the desired 90° peel strength to the copper member. On the other hand, this problem can be solved by performing this process and the release property improvement process independently (i.e., separately). In particular, the peelability improving step is important for imparting the desired 90° peel strength, and it is preferable that this step is independent from the viewpoint that the peelability improving treatment can be carried out under appropriate conditions.

[0082] As the electrolytic plating, nickel plating and nickel alloy plating are preferred. Examples of metals contained in the plating layer formed by nickel plating and nickel alloy plating include pure nickel, Ni-Cu alloy, Ni-Cr alloy, Ni-Co alloy, Ni-Zn alloy, Ni-Mn alloy, Ni-Pb alloy, and Ni-P alloy. Only one of the above electrolytic plating materials may be used, or two or more may be used.

[0083] Examples of metal salts used for plating include nickel sulfate, nickel sulfamate, nickel chloride, nickel bromide, zinc oxide, zinc chloride, diamminedichloropalladium, iron sulfate, iron chloride, chromic anhydride, chromium chloride, sodium chromium sulfate, copper sulfate, copper pyrophosphate, cobalt sulfate, manganese sulfate, etc. The plating solution may contain additives such as a pH buffer and a brightener.

[0084] In nickel plating, the composition of the plating solution is not particularly limited, and is preferably, for example, one containing nickel sulfate (concentration, for example, 100 to 350 g / L), nickel sulfamate (concentration, for example, 100 to 600 g / L), nickel chloride (concentration, for example, greater than 0 g / L and less than or equal to 300 g / L), or a mixture thereof. Furthermore, the plating solution may further contain additives such as sodium citrate (concentration, for example, greater than 0 g / L and less than or equal to 100 g / L) or boric acid (concentration, for example, greater than 0 g / L and less than or equal to 60 g / L).

[0085] When electrolytic plating is applied to the surface of an oxidized copper material, first, the copper oxide on the surface is reduced to cuprous oxide or pure copper using an electric charge. Then, the metal corresponding to the electrolytic plating used begins to deposit, forming a metal layer. The amount of electric charge required varies depending on the type of plating solution and the amount of copper oxide. For example, when Ni plating is applied to a copper material, the area of ​​the copper material to be electrolytically plated is dm 2 It is preferable to apply a charge of 5 C or more and 90 C or less, and more preferable to apply a charge of 10 C or more and 65 C or less per unit area dm 2 It is preferable to apply a charge of 5 C or more and 90 C or less, and more preferable to apply a charge of 10 C or more and 65 C or less per charge.

[0086] The current density in electroplating is not particularly limited, but is preferably 0.2 to 10 A / dm 2 It is preferable to use a current having a different current density for the time until the oxide contained in the protrusions on the surface of the copper material is partially reduced and for the time during which the plating is being coated.

[0087] The amount of metal deposited on the surface of the copper material by plating is not particularly limited, but is preferably 0.8 to 6.0 mg / dm 2 The amount of metal adhesion can be calculated, for example, by dissolving the surface of the copper material in an acidic solution, measuring the amount of metal by ICP analysis, and dividing the amount by the plan view area of ​​the structure.

[0088] (Laminate formation process) The laminate formation step is a step of forming a laminate by laminating a resin substrate and a copper member so that the resin substrate and the protrusions formed on the surface of the copper member abut against each other. This step allows the laminate of embodiment 2 to be obtained. In this step, the laminate may be formed by applying pressure while heating the laminate as needed. That is, this step may be a step of laminating a resin substrate and a copper member so that the resin substrate and the protrusions formed on the surface of the copper member abut against each other, and then applying pressure while heating as needed to form a laminate. This step is performed after the peelability improvement step. If the present invention includes a copper material plating treatment step, this step may be performed thereafter.

[0089] When the resin substrate and the copper member are laminated together, the surface profile of the copper member, including the protrusions, is transferred to the resin substrate. Examples of methods for laminating the resin substrate and the copper member include, for example, laminating the resin substrate to the surface of the copper member while heating part or all of the copper member as necessary, and applying pressure from the copper member side, the resin substrate side, or both under predetermined conditions. The predetermined conditions (e.g., temperature, pressure, time, etc.) can be set appropriately, or conditions recommended by each substrate manufacturer can be used. The predetermined conditions are described below.

[0090] (A) When the resin substrate contains or is made of an epoxy resin, it is preferable to thermocompression bond the copper member to the resin substrate by applying a pressure of 0 to 20 MPa at a temperature of 50°C to 300°C for 1 minute to 5 hours.

[0091] When the (A-1) resin substrate is R-1551 (manufactured by Panasonic Industries Co., Ltd.), it is heated under a pressure of 1.2 MPa, and after reaching 130°C, it is held at that temperature for 10 minutes. Thereafter, it is further heated under a pressure of 2.3 MPa, and after reaching 190°C, it is held at that temperature for 50 minutes, thereby achieving thermocompression bonding. (A-2) When the resin substrate is R-1410A (manufactured by Panasonic Industries Co., Ltd.), it is heated under a pressure of 1 MPa, and after reaching 130°C, it is held at that temperature for 10 minutes. It is then further heated under a pressure of 2.9 MPa, and after reaching 200°C, it is held at that temperature for 70 minutes, thereby achieving thermocompression bonding. (A-3) When the resin substrate is EM-285 (manufactured by Elite Materials Co., Ltd.), it can be thermocompression bonded by heating it under a pressure of 0.4 MPa, and after it reaches 100°C, increasing the pressure to 2.4 to 2.9 MPa and heating it further, and after it reaches 195°C, holding it at that temperature for 50 minutes. (A-4) When the resin substrate is GX13 (manufactured by Ajinomoto Fine-Techno Co., Ltd.), thermocompression bonding can be achieved by heating while applying pressure at 1.0 MPa and maintaining the temperature at 180°C for 60 minutes.

[0092] (B) When the resin substrate contains or consists of a PPE resin, it is preferable to thermocompression bond the copper member to the resin substrate by applying a pressure of 0 to 20 MPa at a temperature of 50°C to 350°C for 1 minute to 5 hours.

[0093] (B-1) When the resin substrate is R-5620 (manufactured by Panasonic Industries Co., Ltd.), the substrate is thermocompression bonded while being heated to 100°C under a pressure of 0.5 MPa, and then the temperature and pressure are increased to 2.0 to 3.0 MPa and 200 to 210°C, and the substrate is held for 120 minutes, thereby achieving further thermocompression bonding. (B-2) When the resin substrate is R-5670 (manufactured by Panasonic Industries Co., Ltd.), thermocompression bonding can be achieved by heating to 110°C under a pressure of 0.49 MPa, then increasing the temperature and pressure and holding at 2.94 MPa and 210°C for 120 minutes. (B-3) When the resin substrate is R-5680 (manufactured by Panasonic Industries Co., Ltd.), thermocompression bonding can be achieved by heating under a pressure of 0.5 MPa until the temperature reaches 110°C, then increasing the temperature and pressure to 3.0 to 4.0 MPa and 195°C, and holding for 75 minutes. (B-4) When the resin substrate is N-22 (manufactured by Nelco Corporation), thermocompression bonding can be achieved by heating while applying pressure of 1.6 to 2.3 MPa, holding at 177°C for 30 minutes, and then further heating and holding at 216°C for 60 minutes.

[0094] (C) When the resin substrate contains or is made of a PTFE resin, it is preferable to thermocompression bond the copper member to the resin substrate by applying a pressure of 0 to 20 MPa at a temperature of 50°C to 400°C for 1 minute to 5 hours.

[0095] (C-1) When the resin substrate is NX9255 (manufactured by Park Electrochemical Co., Ltd.), it can be thermocompression bonded by heating it to 260°C while applying a pressure of 0.69 MPa, then increasing the pressure to 1.03 to 1.72 MPa and heating it to 385°C, and holding it at 385°C for 10 minutes. (C-2) If the resin substrate is RO3003 (manufactured by Rogers Co., Ltd.), thermocompression bonding can be achieved by applying a pressure of 2.4 MPa 50 minutes after the start of pressing (approximately 220°C) and holding at 371°C for 30 to 60 minutes.

[0096] (D) When the resin substrate contains or consists of a liquid crystal polymer (LCP), it is preferable to thermocompression bond the copper member to the resin substrate by applying a pressure of 0 to 20 MPa for 1 minute to 5 hours at a temperature of 50 to 400°C. For example, when the resin substrate is CT-Z (manufactured by Kuraray Co., Ltd.), thermocompression bonding can be achieved by heating under a pressure of 0 MPa, holding at 260°C for 15 minutes, then further heating while applying a pressure of 4 MPa, and holding at 300°C for 10 minutes.

[0097] (Laminate separation process) The laminate separation process is a process in which, after the laminate formation process, the resin substrate and the copper member are separated, and the protrusions formed on the surface of the copper member are transferred to the resin substrate, thereby forming a seed layer containing copper and / or copper oxide on the surface of the resin substrate. Here, "transfer" refers to the movement of the protrusions toward the resin substrate, and as a result, the surface profile of the copper member including the protrusions is imparted to the resin substrate. Methods for confirming the completion of the transfer include a change in color of the resin substrate surface, observation of the cross section of the resin substrate, and component analysis of the resin substrate surface (e.g., detection of copper member components by EDS analysis or XPS analysis).

[0098] The method for separating the resin substrate and the copper member is not particularly limited, but may be, for example, a method of peeling the copper member from the resin substrate. In this process, if necessary, copper oxide derived from the copper member that has transferred to a region other than the desired region on the surface of the resin substrate may be removed by etching. The desired region may be, for example, a region that represents the shape of an electronic circuit on a printed circuit board.

[0099] The seed layer will be explained using Figures 3(a) and (b). 21 and 23 are the resin substrate, 22 and 24 are the protrusions, and 25 is the ultra-thin copper foil. The black areas represent the protrusions transferred to the resin substrate. When the copper member and the resin substrate are separated, the protrusions formed on the surface of the copper member are transferred to the resin substrate by piercing the surface. The lower part of Figure 3, i.e., the area from the base of the protrusion to its tip, is the seed layer. D1 and D2 are schematic representations of the thickness of the seed layer. A seed layer formed using a conventional carrier-attached copper foil used in the semi-additive process can be illustrated in Figure 3(b). This seed layer is formed by transferring the ultra-thin copper foil from the carrier-attached copper foil to the resin substrate. The ultra-thin copper foil 25 has protrusions 24 on its surface. For example, if the thickness of the ultra-thin copper foil 25 is 1.5 μm and the height of the protrusions 24 is approximately 0.8 μm, the thickness of the seed layer D2 will also be approximately 2.3 μm.

[0100] As described above, the conventional carrier-attached copper foil has a three-layer structure in which a carrier foil, a release layer, and an ultrathin copper foil are laminated in this order. A specific material (e.g., a resin) is used as the release layer to enable the carrier foil and the ultrathin copper foil to be peeled from each other. Therefore, a release layer such as a resin remains on the surface of the seed layer, which may need to be removed by cleaning or other means. The present invention is preferable in that it does not require the removal of the release layer. Furthermore, since the carrier-attached copper foil has a release layer made of a specific material, the metal layer obtained by plating after peeling tends to be nonuniform. Since the present invention does not have a release layer, the metal layer obtained after plating tends to be uniform.

[0101] The method for peeling the copper member from the resin substrate is not particularly limited, but may be performed based on a 90° peel test (Japanese Industrial Standards (JIS) C5016 "Test Methods for Flexible Printed Wiring Boards"; corresponding international standards IEC249-1:1982, IEC326-2:1990). In this case, the angle in the direction of peeling the copper member is maintained at 90±5° relative to the surface on which pressure was applied for adhesion. Alternatively, the copper member may be peeled manually, in which case it is peeled at an angle of 80 to 180° relative to the surface on which pressure was applied.

[0102] In the resin substrate with a seed layer obtained by thermocompression bonding a resin substrate to the surface of the copper member having the protrusions to form a laminate, and then peeling the copper member from the resin substrate in the laminate, the thickness of the seed layer is, for example, preferably 30 nm or more, more preferably 50 nm or more, even more preferably 80 nm or more, and particularly preferably 120 nm or more. Also, for example, it is preferably 500 nm or less, more preferably 400 nm or less, even more preferably 300 nm or less, particularly preferably 250 nm or less, and most preferably 200 nm or less.

[0103] The thickness of the seed layer will be described more specifically below. A resin substrate, R-1551 (manufactured by Panasonic Industries Co., Ltd.), is heated to 130°C and pressure-bonded to the surface of the copper member on which the protrusions are formed (i.e., the treated surface) at 1.2 MPa. After reaching 130°C, the temperature is maintained at that temperature for 10 minutes. After reaching 190°C under a pressure of 2.3 MPa, the temperature is maintained at that temperature for 50 minutes to form a thermocompression bond, forming a laminate. The degree of vacuum is 2 kPa or less. The copper member is peeled from the resin substrate in a 90° direction at a rate of 50 mm / min using the resulting laminate in accordance with a 90° peel test (Japanese Industrial Standards (JIS) C5016), to obtain a resin substrate with a seed layer. The thickness of the seed layer may be the same as the thickness of the seed layer in the resin substrate with a seed layer obtained by the above method.

[0104] In addition, the thickness of the seed layer can be measured, similarly to the "average height of the protrusions" described using Figure 5, by taking the height of the protrusions as the distance between the midpoint of the line segment connecting the minimum points of adjacent recesses separated by a predetermined distance and the maximum point of the protrusion between the recesses in a cross-sectional image taken by a scanning electron microscope (SEM) and calculating the average value.

[0105] (Resin substrate plating process) The resin substrate plating step is a step of plating the surface of the resin substrate using a plating solution after the laminate separation step. More specifically, it is a step of plating copper or copper oxide on the surface of the resin substrate by plating the surface of the resin substrate on which the seed layer has been formed. In this step, the copper or copper oxide on the surface of the resin substrate is plated, while the resin substrate is not plated, so that the metal layer formed by plating can be used as wiring for printed circuit boards (particularly printed wiring boards, semiconductor package substrates, etc.).

[0106] The plating method is not particularly limited, and may be electrolytic plating or electroless plating. The metal contained in the plating is also not particularly limited, and for example, at least one metal selected from the group consisting of Ni, Sn, Al, Cr, Co, and Cu can be used. From the viewpoint of obtaining a highly accurate wiring pattern, electroless plating using copper is preferred. Furthermore, it is particularly preferred to perform electroless plating using copper in the absence of a catalyst. By not using a catalyst, it tends to be possible to perform electroless plating selectively on the transferred pattern. The thickness of the plating is not particularly limited, and may be approximately 0.02 to 2 μm.

[0107] The printed wiring board and semiconductor package substrate as printed circuit boards will be explained using Figure 4. In Figure 4, 31 is an example of a printed circuit board on which electronic components are mounted. 32 is a semiconductor chip, 33 is solder bumps, 34 is an encapsulant, 35 is a semiconductor package substrate, 36 is solder balls, 37 is an encapsulant, and 38 is a printed wiring board. The semiconductor package substrate 35 is a substrate used to transmit electrical signals between the semiconductor chip 32 and the printed wiring board 38. [Example]

[0108] The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples.

[0109] [Example 1 and Comparative Example 1] (1) Copper foil treatment The following treatment was carried out using the shiny side of a copper foil (product name: DR-WS, thickness: 18 μm, manufactured by Furukawa Electric Co., Ltd.). The shiny side is also called the glossy side, and refers to the side that is flatter than the other side. The other side is called the matte side (non-glossy side).

[0110] (1-1) Acid treatment The copper foil was immersed in 8% by volume sulfuric acid at a liquid temperature of 25° C. for 2 minutes to remove dirt from the copper surface, and then the copper foil was washed with water.

[0111] (1-2) Pretreatment The copper foil after the treatment according to (1-1) was degreased by immersing it in a 5 g / L aqueous potassium hydroxide solution at a liquid temperature of 25°C for 1 minute to remove dirt from the copper surface. Thereafter, the obtained copper foil was washed with water.

[0112] (1-3) Oxidation treatment The shiny side of the copper foil after the treatment in (1-2) was immersed in an oxidizing agent (sodium chlorite 227.5 g / L, potassium hydroxide 21 g / L, 3-glycidoxypropyltrimethoxysilane 0.5 g / L) at a temperature of 50°C for 1 minute to perform an oxidation treatment, thereby forming fine protrusions on the surface of the copper foil. The resulting copper foil was then washed with water and dried. The thickness of the formed copper oxide layer was 51 nm. The thickness of the copper oxide layer is measured using the SERA method and refers to the thickness when converted into a uniform state. Details of the measurement using the SERA method will be described later.

[0113] (1-4) Peelability improvement treatment The copper foil after the treatment according to (1-3) was immersed in a 45 g / L aqueous solution of nickel chloride hexahydrate at a liquid temperature of 45°C for 2 minutes as a pre-plating treatment. The obtained copper foil was then rinsed with water. This was designated Example 1. Furthermore, the solution temperature was changed to 60°C, the concentration of the nickel chloride hexahydrate aqueous solution was changed to 10 g / L, and the immersion time was changed to 10 minutes to designate Comparative Example 1.

[0114] (1-5) Electroplating The copper foil after the treatment according to (1-4) was immersed in a Ni electroplating solution (nickel sulfate hexahydrate 240 g / L, trisodium citrate 20 g / L) at a liquid temperature of 45°C, and then subjected to a current density of 0.5 A / dm 2 Electrolytic plating was performed under the conditions of 100°C, 41 seconds, and 100°F. The obtained copper foil was then washed with water and dried. The thickness of the obtained Ni was 31 nm. The amount of Ni attached was calculated by dissolving the copper foil surface in an acidic solution, measuring the amount of Ni by ICP analysis, and dividing the amount by the plan view area of ​​the structure. The same applies to the Ni thickness described below.

[0115] (2) Measurement of copper oxide layer thickness The thickness of the copper oxide layer before plating was measured by the SERA method for Example 1 and Comparative Example 1. The measurement device used was a Surface-Scan QC-100 (manufactured by ECI Corporation). Measurements were performed using a boric acid solution (6.18 g / L boric acid, 9.55 g / L sodium tetraborate) at a constant current (90 μA / cm 2 ) and the reduction time was measured within the following voltage range. Cu2O=-0.3V~-0.55V CuO=-0.55V~-0.85V The obtained reduction time and the current density were substituted into the following equation to convert into a film thickness. CuO film thickness (nm) = 0.0124 × current density (μA / cm 2 ) × reduction time (sec) × 0.1 CuO film thickness (nm) = 0.00639 × current density (μA / cm 2 ) × reduction time (sec) × 0.1 The "Thickness of copper oxide layer (nm)" section of Table 1 shows the calculated thickness of the copper oxide layer.

[0116] (3) Plating thickness (flat surface equivalent) The amount of Ni attached per unit area was measured. First, the copper member was dissolved in 12% nitric acid, and the concentration of Ni metal components in the resulting liquid was measured using an ICP optical emission spectrometer 5100 SVDV ICP-OES (manufactured by Agilent Technologies). This was used as the amount of Ni attached per unit area of ​​the copper member used.

[0117] The plating thickness in terms of planar surface was calculated using the following formula. "Plating thickness (flat surface equivalent) (nm)" = (metal deposition amount per unit area (mg / dm 2 ) / metal density (g / cm 3 ))×100 The density of Ni is 8.91 g / cm 3 In addition, the plating thickness was calculated assuming that the metal contained was Ni.

[0118] (4) Evaluation The copper members of Example 1 and Comparative Example 1, and the copper members of Comparative Examples 2 and 3 below, were evaluated as follows. Comparative Example 2: Ultra-thin copper foil with carrier manufactured by Mitsui Mining & Smelting Co., Ltd., product name: MT18FL, ultra-thin copper foil thickness: 1.5 μm Comparative Example 3: Ultra-thin copper foil with carrier manufactured by Fukuda Metal Foil & Powder Co., Ltd., product name: FUTF-3WAF-2, ultra-thin copper foil thickness: 2 μm

[0119] (Evaluation 1: 90° peel strength measurement) A resin substrate, R-1551 (manufactured by Panasonic Industries Co., Ltd.), was heated to 130°C and pressure-bonded to the treated surface of the copper members of Example 1 and Comparative Examples 1 to 3 at 1.2 MPa. After reaching 130°C, the temperature was maintained at 130°C for 10 minutes. The temperature was then maintained at 190°C under a pressure of 2.3 MPa for 50 minutes, completing the thermocompression bonding. The degree of vacuum was 2 kPa or less. The resulting samples (copper member and resin substrate laminates) were subjected to a 90° peel test (Japanese Industrial Standard (JIS) C5016) to measure the peel strength (gf / cm) when the copper member was peeled from the resin substrate at a rate of 50 mm / min in a 90° direction. The measurement width of the measurement sample was 10 mm. The measurement results are shown in the "Peel Strength (gf / cm)" section of Table 1.

[0120] (Evaluation 2: Adhesion evaluation) The treated surfaces of the copper members of Example 1 and Comparative Examples 1 to 3 were subjected to a cross-cut adhesion test in accordance with JIS K-5600-5-6:1999. Specifically, 25 cross-cuts with a width of 1 mm were made on the treated surfaces of the copper members, tape was adhered to the cross-cut areas and then peeled off, and adhesion was evaluated according to the following criteria. The evaluation results are shown in the "Evaluation of Adhesion" section of Table 1. [Evaluation criteria] Category 0: No peeling at all Category 1: Only small peeling of the paint film at the intersection of the cuts. Category 2: Peeling along the cut lines at the intersections. Peeling area is 5% to less than 15%. Category 3: Partial or complete peeling along the cut line. Peeling area is 15% or more but less than 35%. Category 4: Peeling occurs along the entire cut line. Peeling area is 35% or more but less than 65%. Category 5: Peeling is greater than Category 4.

[0121] [Table 1]

[0122] As can be seen from Table 1, the copper member of Comparative Example 1 had a high 90° peel strength, which meant that the copper member could not be easily peeled from the resin substrate, and the workability was insufficient, so the handleability was not good. Furthermore, Comparative Examples 2 and 3 had moderately low 90° peel strength values, meaning that the copper member could be easily peeled from the resin substrate, but the adhesion evaluation showed extremely low adhesion, meaning that peeling easily occurred even when the copper foil touched an unintended portion in the semi-additive process, and therefore the handleability was not good. On the other hand, the copper member of Example 1 had a moderately low 90° peel strength value, meaning that the copper member could be easily peeled from the resin substrate in the semi-additive process, and the adhesion evaluation showed moderately high adhesion, meaning that peeling did not occur even when the copper foil touched an unintended portion, so the handleability was good. [Explanation of symbols]

[0123] 1 Copper materials 2 Copper material 3 Copper oxide layer 4 protrusions 5 Metal layers other than copper 10 Laminate 11 Copper materials 12 Resin substrate 21 Resin substrate 22 protrusions 23 Resin substrate 24 protrusions 25 Ultra-thin copper foil D1 seed layer thickness D2 seed layer thickness 31 Printed circuit board with electronic components mounted 32 Semiconductor chips 33 Solder Bumps 34 Sealing body 35 Semiconductor package substrate 36 solder balls 37 Sealing body 38 Printed Wiring Board L Protrusion height 41 Copper foil 42 Protrusion

Claims

1. A copper member including a copper material and a protrusion formed on a part or all of a surface of the copper material, the copper material and the protrusion being formed so as to be separable from each other, the protrusions contain copper and / or copper oxide; A copper member having a 90° peel strength of 120 gf / cm or less when pressed against a resin substrate and then peeled off.

2. a copper oxide layer; The copper member according to claim 1 , wherein the protrusions are formed as part or all of the copper oxide layer.

3. including a metal layer other than copper, The copper member according to claim 2 , wherein a metal layer other than copper is formed so as to cover a part or all of the surface of the copper oxide layer.

4. The copper member according to claim 1 or 2, wherein the height (average height) of the protrusions is 30 nm or more.

5. The copper member according to claim 2 , wherein the copper oxide layer has a thickness of 500 nm or less.

6. 3. The copper member according to claim 1 or 2, wherein a resin substrate with a seed layer is obtained by thermocompression bonding a resin substrate to a surface of the copper member on which a protrusion is formed to form a laminate, and then peeling the copper member from the resin substrate in the laminate, and the seed layer has a thickness of 30 nm or more.

7. The copper member according to claim 1 or 2, wherein the evaluation is classification 0 in a cross-cut adhesion test in accordance with JIS K-5600-5-6:1999.

8. 3. A laminate comprising the copper member according to claim 1 and a resin base material laminated together such that the resin base material abuts against protrusions formed on the surface of the copper member.

9. 9. The laminate according to claim 8, wherein the resin substrate comprises at least one insulating resin selected from the group consisting of polyphenylene ether (PPE), epoxy, polyphenylene oxide (PPO), polybenzoxazole (PBO), polytetrafluoroethylene (PTFE), liquid crystal polymer (LCP), thermoplastic polyimide (TPI), fluororesin, polyetherimide, polyetheretherketone, polycycloolefin, bismaleimide resin, low dielectric constant polyimide, and cyanate resin.

10. A method for manufacturing a printed circuit board including a resin substrate and a wiring pattern formed on a surface of the resin substrate, forming protrusions containing copper and / or copper oxide on a part or all of the surface of a copper material; a step of treating the copper material with a release agent to obtain the copper member according to claim 1; a step of laminating a resin base material and the copper member such that the resin base material and the protrusions formed on the surface of the copper member abut against each other to form a laminate; a step of separating the resin substrate and the copper member, and transferring protrusions formed on the surface of the copper member to the resin substrate, thereby forming a seed layer containing copper and / or copper oxide on the surface of the resin substrate; a step of plating a surface of the resin substrate using a plating solution; A method for manufacturing a printed circuit board, comprising:

11. 11. The method for manufacturing a printed circuit board according to claim 10, further comprising the step of plating a surface of the copper member using a plating solution between the step of treating the copper material with a release agent and the step of forming the laminate.

12. The step of forming the protrusions includes: The method for producing a printed circuit board according to claim 10, wherein the step of forming protrusions containing copper oxide is carried out by oxidation treatment.

13. The method for manufacturing a printed circuit board according to claim 12, wherein the oxidation treatment is carried out using an oxidizing agent.

14. The method for producing a printed circuit board according to claim 10, wherein in the step of plating the surface of the resin base material using a plating solution, the plating is an electroless plating treatment.

15. 11. The method for producing a printed circuit board according to claim 10, wherein in the step of plating the surface of the resin base material with a plating solution, the plating is an electroless plating treatment using Cu.

16. A method for producing a resin substrate with a seed layer, the method comprising: a resin substrate; and a seed layer containing copper and / or copper oxide formed on a surface of the resin substrate, the method comprising: forming protrusions containing copper and / or copper oxide on a part or all of the surface of a copper material; a step of treating the copper material with a release agent to obtain the copper member according to claim 1; a step of laminating a resin base material and the copper member such that the resin base material and the protrusions formed on the surface of the copper member abut against each other to form a laminate; a step of separating the resin substrate and the copper member, and transferring protrusions formed on the surface of the copper member to the resin substrate, thereby forming a seed layer containing copper and / or copper oxide on the surface of the resin substrate; A method for producing a resin substrate with a seed layer, comprising:

17. 17. The method for producing a resin substrate with a seed layer according to claim 16, further comprising a step of plating a surface of the copper member using a plating solution between the step of treating the copper material with a release property improver and the step of forming the laminate.

18. forming protrusions containing copper and / or copper oxide on a part or all of the surface of a copper material; treating the copper material with a release agent; The method for producing a copper member according to claim 1 , comprising:

19. The method for producing a copper member according to claim 18, further comprising the step of plating a surface of the copper member with a plating solution after the step of treating the copper material with a strippability improver.

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