Metal foil with carrier and method for manufacturing the same

Abstract

Provided is a carrier-attached metal foil which has a metal layer that does not easily peel off at an edge of the carrier-attached metal foil, or at a cut position of the downsized carrier-attached metal foil, and therefore which makes it easy to form an intended circuit pattern, effectively curbs the decrease of strength of the carrier, and is able to be desirably used in a mass-production process. This carrier-attached metal foil comprises: a carrier; a peeling layer attached on the carrier; and a metal layer with a thickness ranging from 0.01 μm to 4.0 μm inclusive, attached on the peeling layer. The carrier has, at least on its surface on the metal layer side, a flat region with a developed interfacial area ratio Sdr of less than 5% measured in accordance with ISO25178, and an uneven region with a developed interfacial area ratio Sdr of 5% to 39% inclusive measured in accordance with ISO25178. The uneven region is formed into a line pattern surrounding the flat region.

Description

[Technical Field] 【0001】 The present invention relates to a metal foil with a carrier and a method for manufacturing the same. [Background technology] 【0002】 With the recent miniaturization and increased functionality of electronic devices such as portable electronic devices, there is a growing demand for even finer wiring patterns (fine pitch) on printed circuit boards. To meet this demand, there is a need for metal foils for the manufacture of printed circuit boards that are thinner and have lower surface roughness than before. For example, Patent Document 1 (Japanese Patent Application Publication No. 2005-76091) discloses a method for manufacturing ultra-thin copper foil with a carrier, which includes sequentially laminating a release layer and an ultra-thin copper foil onto the smooth surface of a carrier copper foil having an average surface roughness Rz of 0.01 μm to 2.0 μm. It also discloses obtaining a multilayer printed circuit board by applying high-density ultra-fine wiring (fine pattern) using this ultra-thin copper foil with a carrier. 【0003】 Furthermore, in order to further reduce the thickness and surface roughness of the metal layer in carrier-attached metal foil, it has recently been proposed to use glass substrates or polished metal substrates as ultra-smooth carriers instead of the resin carriers that have been typically used conventionally, and to form the metal layer on this ultra-smooth surface by a vapor phase method such as sputtering. For example, Patent Document 2 (International Publication No. 2017 / 150283) discloses a carrier-attached copper foil comprising a carrier (e.g., a glass carrier), a release layer, an anti-reflective layer, and an ultra-thin copper layer in that order, and it is described that the release layer, anti-reflective layer, and ultra-thin copper layer are formed by sputtering. Also, Patent Document 3 (International Publication No. 2017 / 150284) discloses a carrier-attached copper foil comprising a carrier (e.g., a glass carrier), an intermediate layer (e.g., an adhesive metal layer and a release assist layer), a release layer, and an ultra-thin copper layer, and it is described that the intermediate layer, release layer, and ultra-thin copper layer are formed by sputtering. In both Patent Documents 2 and 3, each layer is sputtered onto a carrier such as glass with excellent surface flatness, thereby achieving an extremely low arithmetic mean roughness Ra of 1.0 nm to 100 nm on the outer surface of the ultrathin copper layer. 【0004】 Incidentally, when transporting metal foil with a carrier, the laminated portion of the carrier and the metal layer may come into contact with other components, causing unexpected delamination of the metal layer. Several metal foils with carriers have been proposed to address this problem. For example, Patent Document 4 (JP 2016-137727 A) discloses a laminate in which part or all of the outer circumference of the metal carrier and the metal foil is covered with resin. This configuration prevents contact with other components and reduces delamination of the metal foil during handling. Patent Document 5 (International Publication No. 2014 / 054812) discloses a metal foil with a carrier in which the interface between the resin carrier and the metal foil is firmly bonded via an adhesive layer at at least four corners of the outer circumference, thereby preventing unexpected delamination at the corners. It also discloses that the metal foil with carrier can be cut at the portion inside the adhesive layer after transport is complete. Patent document 6 (Japanese Patent Publication No. 2000-331537) discloses a copper foil carrier in which the surface roughness of the areas near the left and right edges of the copper foil carrier is greater than that of the central area. It is stated that this prevents problems such as the copper layer peeling off from the carrier when handling the copper foil carrier or when manufacturing copper-clad laminates. Patent document 7 (International Publication No. 2019 / 163605) discloses providing a linear uneven region with a maximum height Rz of 1.0 μm to 30.0 μm as a cutting allowance on the surface of a flat glass carrier. It is stated that this prevents undesirable peeling of the copper layer during and after cutting of the copper foil carrier. [Prior art documents] [Patent Documents] 【0005】 [Patent Document 1] Japanese Patent Publication No. 2005-76091 [Patent Document 2] International Publication No. 2017 / 150283 [Patent Document 3] International Publication No. 2017 / 150284 [Patent Document 4] Japanese Patent Publication No. 2016-137727 [Patent Document 5] International Publication No. 2014 / 054812 [Patent Document 6] Japanese Patent Publication No. 2000-331537 [Patent Document 7] International Publication No. 2019 / 163605 [Overview of the Initiative] 【0006】 When mounting IC chips and other components onto a substrate, there is an upper limit to the size of the substrate that the mounting equipment can process, and a typical size of carrier-attached metal foil (e.g., 400mm x 400mm) exceeds this limit. Therefore, carrier-attached metal foil is cut to a size that the mounting equipment can process, downsizing it to, for example, a width of about 100mm. However, when cutting carrier-attached metal foil, the peel strength of the release layer exposed at the cutting interface is low, and the metal layer may peel off from the carrier due to the load during cutting. As a result, it may not be possible to form the intended circuit pattern, and the process may not be able to proceed to the next step. In addition, when using SiO2 substrates, Si single crystal substrates, or glass as carriers, defects such as chipping (breakage) at the carrier edges are likely to occur when cutting carrier-attached metal foil. 【0007】 To address these problems, as shown in Patent Document 7, it is conceivable to make it more difficult for the metal layer to peel off at the edges of the carrier-attached metal foil or at the cut edges of downsized carrier-attached metal foil by providing linear uneven regions on the surface of the carrier in the carrier-attached metal foil. On the other hand, if uneven regions are formed on the inherently flat carrier surface by physical methods such as blasting, the strength of the carrier decreases, and as a result, there is a high concern that the carrier will crack. A carrier that has cracked cannot be used in subsequent manufacturing processes, and therefore, mass production of carrier-attached metal foil and printed circuit boards using it will be hindered due to reduced yield and process stoppages. Therefore, there is room for improvement from the standpoint of achieving both the prevention of undesirable peeling of the metal layer from the edges or cut surfaces of the carrier-attached metal foil and the prevention of a decrease in the strength of the carrier. 【0008】 The present inventors have now found that, in a carrier-attached metal foil, by providing an uneven region on the inherently flat surface of the carrier, where the interface development area ratio Sdr is controlled to a predetermined range as a cutting allowance, the metal layer is less likely to peel off at the edges of the carrier-attached metal foil or at the cutting points of downsized carrier-attached metal foils, making it easier to form the intended circuit pattern, and moreover, the reduction in carrier strength is effectively suppressed, making it desirable for use in mass production processes. 【0009】 Therefore, the object of the present invention is to provide a carrier-attached metal foil in which the metal layer is less likely to peel off at the edges of the carrier-attached metal foil or at the cut points of a downsized carrier-attached metal foil, thus making it easier to form the intended circuit pattern, and in which the reduction in carrier strength is effectively suppressed, making it desirable for use in mass production processes. 【0010】 According to one aspect of the present invention, Career and, A release layer provided on the carrier, A metal layer with a thickness of 0.01 μm or more and 4.0 μm or less is provided on the aforementioned release layer, Equipped with, The carrier has a flat region with a surface development area ratio Sdr of less than 5% measured in accordance with ISO 25178 at least on the surface side of the metal layer, and a concavo-convex region with a surface development area ratio Sdr of 5% or more and 39% or less measured in accordance with ISO 25178, and the concavo-convex region is provided in a linear pattern surrounding the flat region. A metal foil with a carrier is provided. 【0011】 According to another aspect of the present invention, there is provided a method for manufacturing the metal foil with a carrier, a step of preparing a carrier having at least one surface that is a flat surface with a surface development area ratio Sdr of less than 5% measured in accordance with ISO 25178; a step of roughening at least the outer peripheral portion of the surface of the carrier to form a concavo-convex region with a surface development area ratio Sdr of 5% or more and 39% or less measured in accordance with ISO 25178 in a linear pattern; a step of forming a release layer on the carrier; a step of forming a metal layer with a thickness of 0.01 μm or more and 4.0 μm or less on the release layer; A manufacturing method including the above is provided. 【0012】 According to still another aspect of the present invention, there is provided a method for manufacturing a metal foil with a carrier, including cutting the metal foil with a carrier along the pattern in the concavo-convex region so that the metal foil with a carrier is divided into a plurality of sheets. 【Brief Description of the Drawings】 【0013】 [Figure 1] It is a perspective view schematically showing one aspect of the metal foil with a carrier of the present invention. [Figure 2] It is a schematic cross-sectional view showing the layer structure of a portion including the concavo-convex region surrounded by the dashed-dotted line of the metal foil with a carrier shown in FIG. 1. [Figure 3] It is a perspective view schematically showing the carrier included in the metal foil with a carrier shown in FIG. 1. [Figure 4]This is a schematic cross-sectional view showing a metal foil with a carrier cut on an uneven surface. [Figure 5] This is a schematic top view showing the carriers that have formed a masking layer. [Figure 6A] This is a schematic cross-sectional view illustrating the method for measuring the breaking load. [Figure 6B] Figure 6A is a schematic top view showing the positional relationship between the carrier and the support member S. [Modes for carrying out the invention] 【0014】 definition In this specification, "interface area ratio Sdr" or "Sdr" is a parameter that represents how much the expanded area (surface area) of a defined region increases relative to the area of ​​the defined region, as measured in accordance with ISO 25178. In this specification, the interface area ratio Sdr is expressed as the increase in surface area (%). A smaller value indicates a surface shape that is closer to flat, with a perfectly flat surface having an Sdr of 0%. On the other hand, a larger value indicates a surface shape with more irregularities. For example, if the Sdr of a surface is 30%, it indicates that the surface area of ​​this surface has increased by 30% compared to a perfectly flat surface. The interface area ratio Sdr is calculated using a predetermined measurement area (e.g., 12690 μm²) on the target surface. 2 The surface profile (in the two-dimensional region) can be calculated by measuring it with a commercially available laser microscope. In this specification, the numerical value of the interface development area ratio Sdr is the value measured without using cutoffs by S filters and L filters. 【0015】 Metal foil with carrier An example of the carrier-attached metal foil of the present invention is schematically shown in Figures 1 and 2. As shown in Figures 1 and 2, the carrier-attached metal foil 10 of the present invention comprises a carrier 12, a release layer 16, and a metal layer 18 in this order. The release layer 16 is a layer provided on the carrier 12. The metal layer 18 is provided on the release layer 16 and is a layer with a thickness of 0.01 μm or more and 4.0 μm or less. If desired, the carrier-attached metal foil 10 may further have an intermediate layer 14 between the carrier 12 and the release layer 16 that can contribute to improving adhesion. Furthermore, the carrier-attached metal foil 10 may further have a functional layer 17 between the release layer 16 and the metal layer 18 that can function as a stopper layer during etching. Furthermore, the above-mentioned various layers may be provided in order on both sides of the carrier 12 in an up-down symmetrical manner. The carrier-attached metal foil 10 is not particularly limited, except that it comprises a carrier 12 in the form described later, and can adopt any known layer configuration. In any case, in the present invention, as shown in Figures 2 and 3, the carrier 12 has one or more flat regions F on at least the surface facing the metal layer 18, where the interface area ratio Sdr is less than 5%, and uneven regions R where the interface area ratio Sdr is 5% or more and 39% or less. These uneven regions R are provided in a linear pattern surrounding the flat regions F. The uneven regions R may also be provided in a linear pattern that demarcates a plurality of individualized flat regions F. 【0016】 Thus, in a carrier-attached metal foil, by providing linear uneven regions R as a cutting allowance on the inherently flat surface of the carrier 12, the metal layer 18 is less likely to peel off at the edges of the carrier-attached metal foil or at the cut points of downsized carrier-attached metal foil, making it possible to form the intended circuit pattern. In other words, because the carrier 12 has a flat region F with a small interface development area ratio Sdr, the surface of the metal layer 18 laminated on the carrier 12 via the release layer 16 also becomes flat on the flat region F, and this flat surface of the metal layer 18 enables the formation of a fine pattern. Furthermore, the carrier 12 also has an uneven region R with a large interface development area ratio Sdr, and the anchoring effect caused by this unevenness increases the peel strength in the parts formed on the uneven region R of the release layer 16 and the metal layer 18. And since this uneven region R is formed at least on the outer periphery of the carrier 12 so as to surround the flat region F, unintended peeling of the metal layer 18 from the edges of the carrier-attached metal foil can be effectively prevented. Furthermore, the uneven region R of the carrier 12 may be provided in the shape of a linear pattern that demarcates a plurality of individualized flat regions F. In this case, when the carrier-attached metal foil 10 is cut according to the pattern of this uneven region R, a plurality of carrier-attached metal foils 10' can be obtained, each having its own flat region F and downsized to a size that can be processed by the circuit mounting equipment in the subsequent process. The carrier-attached metal foil 10' obtained by cutting along the uneven region R is shown in Figure 4. As shown in Figure 4, because the cut surface of the carrier-attached metal foil 10' is located in the uneven region R, the peel strength of the release layer 16 at the cut surface is high, and therefore, undesirable peeling of the metal layer 18 from the cut surface can be prevented very effectively, not only during cutting but also after cutting (for example, during transport and handling of the carrier-attached metal foil in the mounting process). As a result, it becomes easier to form the intended circuit pattern, and a fine-pitch circuit mounting substrate can be desirablely realized. 【0017】 Therefore, it is preferable that the carrier-attached metal foil 10 of the present invention is cut in a predetermined pattern in the uneven region R so that the carrier-attached metal foil 10 is divided into multiple pieces during the manufacturing process. That is, when downsizing for circuit mounting is required, it is preferable that the carrier-attached metal foil 10 is cut in the uneven region R in a predetermined pattern to be divided into multiple pieces. According to a preferred embodiment of the present invention, a method for manufacturing a carrier-attached metal foil (i.e., a downsized carrier-attached metal foil 10') is provided, which includes cutting the carrier-attached metal foil 10 in the uneven region R in a predetermined pattern so that the carrier-attached metal foil 10 is divided into multiple pieces. The cutting of the carrier-attached metal foil 10 can be carried out according to known methods and is not particularly limited. Examples of preferred cutting methods include dicing, water cutting, and laser cutting. 【0018】 On the other hand, as mentioned above, if an uneven region is formed on an inherently flat carrier surface by physical methods such as blasting, the strength of the carrier decreases, and there is a concern that this may result in the carrier cracking. A carrier that has cracked cannot be used in subsequent manufacturing processes, which can hinder the mass production of carrier-attached metal foil and printed circuit boards using it, such as process stoppages and a decrease in product yield. Thus, it is not easy to prevent both the undesirable peeling of the metal layer from the edges or cut surfaces of carrier-attached metal foil and the reduction in carrier strength. In this regard, the inventors investigated and found that by controlling the Sdr of the carrier's uneven region to a specific range of 5% to 39% in carrier-attached metal foil, it is possible to significantly improve the peeling strength between the carrier and the metal layer in the uneven region while effectively suppressing the reduction in carrier strength. The mechanism by which this effect is achieved is not entirely clear, but one possible factor is as follows: When unevenness exists locally on a flat carrier, compressive stress concentrates at these uneven areas, which easily leads to carrier failure. In this regard, the region where Sdr is between 5% and 39% can be said to have a uniform distribution of irregularities, and as a result of the dispersion of compressive stress, carrier failure is less likely to occur. Therefore, the carrier-attached metal foil 10 of the present invention is less prone to cracking of the carrier 12, so the carrier-attached metal foil itself can be mass-produced with high productivity, and can also be desirablely used in mass production processes of printed circuit boards and the like that are manufactured using the carrier-attached metal foil. 【0019】 The carrier 12 is preferably a silicon-containing substrate or a glass substrate, and more preferably a glass carrier. Any substrate containing Si as an element can be used as the silicon-containing substrate, such as an SiO2 substrate, SiN substrate, Si single-crystal substrate, or Si polycrystalline substrate. The carrier 12 may be in the form of a sheet, film, or plate. Furthermore, the carrier 12 may be a laminate of these sheets, films, and plates. For example, the carrier 12 is preferably a rigid support such as an SiO2 substrate, a Si single-crystal substrate, or a glass plate. More preferably, from the viewpoint of preventing warping of the carrier-attached metal foil 10 in heating processes, the carrier 12 is a Si single-crystal substrate or glass plate with a coefficient of thermal expansion (CTE) of less than 25 ppm / K (typically 1.0 ppm / K to 23 ppm / K). Also, from the viewpoint of handling and ensuring flatness during chip mounting, the micro-Vickers hardness of the carrier 12 is preferably 500 HV to 3000 HV, and more preferably 600 HV to 2000 HV. When glass is used as a carrier, it has advantages such as being lightweight, having a low coefficient of thermal expansion, high insulation properties, high rigidity, and a flat surface, which allows for an extremely smooth surface on the metal layer 18. Furthermore, when the carrier is glass, there are advantages such as excellent visibility when performing image inspection after the wiring layer is formed, having surface flatness (coplanarity) that is advantageous when mounting electronic components, having chemical resistance in desmear and various plating processes in the printed circuit board manufacturing process, and being able to employ a chemical separation method when peeling the carrier 12 from the carrier-attached metal foil 10. The carrier 12 is preferably glass containing SiO2, more preferably glass containing 50% by weight or more of SiO2, and even more preferably glass containing 60% by weight or more of SiO2. Preferred examples of the glass constituting the carrier 12 include quartz glass, borosilicate glass, alkali-free glass, soda-lime glass, aluminosilicate glass, and combinations thereof; more preferably, borosilicate glass, alkali-free glass, soda-lime glass, and combinations thereof; particularly preferably, alkali-free glass, soda-lime glass, and combinations thereof; and most preferably, alkali-free glass.It is preferable that the carrier 12 is composed of borosilicate glass, alkali-free glass, or soda-lime glass, as this reduces chipping of the carrier 12 when cutting the carrier-attached metal foil 10. Alkali-free glass is a glass that is substantially free of alkali metals, mainly composed of silicon dioxide, aluminum oxide, boron oxide, and alkaline earth metal oxides such as calcium oxide and barium oxide, and further containing boric acid. This alkali-free glass has the advantage of minimizing glass warping in processes involving heating, as its coefficient of thermal expansion is low and stable in the range of 3 ppm / K to 5 ppm / K over a wide temperature range from 0°C to 350°C. The thickness of the carrier 12 is preferably 100 μm to 2000 μm, more preferably 300 μm to 1800 μm, and even more preferably 400 μm to 1100 μm. If the carrier 12 has a thickness within this range, it is possible to make the printed circuit board thinner and reduce warping that occurs when mounting electronic components, while ensuring appropriate strength that does not hinder handling. 【0020】 The flat regions F of the carrier 12 (or each of the multiple flat regions F if there are multiple flat regions F) have an interface development area ratio Sdr of less than 5%, preferably 0.01% to 4.0%, more preferably 0.03% to 3.0%, even more preferably 0.05% to 1.0%, particularly preferably 0.07% to 0.50%, and most preferably 0.08% to 0.50%. The smaller the interface development area ratio Sdr of the flat regions F, the more desirable it is to obtain a low interface development area ratio Sdr on the outermost surface of the metal layer 18 laminated on the carrier 12 (i.e., the surface opposite to the release layer 16), which makes it suitable for forming highly miniaturized wiring patterns in printed circuit boards manufactured using the carrier-attached metal foil 10, with a line / space (L / S) of 13 μm or less / 13 μm or less (for example, from 12 μm / 12 μm to 2 μm / 2 μm). 【0021】 The uneven region R of the carrier 12 has an interface development area ratio Sdr of 5% to 39%, preferably 6% to 36%, more preferably 7% to 32%, even more preferably 7% to 25%, and particularly preferably 8% to 22%. This reduces the ease of peeling from the release layer 16 in the uneven region R (improves adhesion). As a result, unintended peeling of the metal layer 18 from the edges of the carrier-attached metal foil 10 can be effectively prevented. Furthermore, if the carrier 12 has a plurality of flat regions F, it is preferable that the uneven region R is provided in a linear pattern that demarcates the plurality of flat regions F. This ensures good peel strength at the cut surface when the carrier-attached metal foil 10 is cut according to the pattern of the uneven region R, and more effectively suppresses undesirable peeling of the metal layer 18 associated with cutting. In addition, since sharp or cracked portions are less likely to occur on the surface of the carrier 12, the number of particulate fragments of the carrier generated when the carrier-attached metal foil 10 is cut can be reduced. Furthermore, the reduction in the strength of the carrier 12 can be suppressed more effectively. The peel strength of the carrier 12 in the uneven region R is preferably 20 gf / cm to 3000 gf / cm, more preferably 25 gf / cm to 2000 gf / cm, even more preferably 30 gf / cm to 1000 gf / cm, particularly preferably 35 gf / cm to 500 gf / cm, and most preferably 50 gf / cm to 300 gf / cm. Within this range, undesirable peeling of the metal layer 18 from the edges or cut surfaces of the carrier-attached metal foil 10 can be effectively suppressed, and the uneven region R can be formed with good productivity. This peel strength is a value measured in accordance with JIS Z 0237-2009, as will be mentioned in the examples described later. 【0022】 The pattern of the uneven region R is preferably arranged in a grid, fence, or cross shape, as this makes it easier to partition the multiple flat regions F into uniform shapes and sizes suitable for a circuit mounting board. In particular, the pattern of the uneven region R is preferably arranged in a grid or fence shape. This allows the entire or most of the area around each flat region F to be surrounded by the uneven region R, making it less likely for a peeling point to occur at the end of each carrier-attached metal foil 10' that has been divided after cutting. 【0023】 The line width of the pattern in the uneven region R is preferably 1 mm to 50 mm, more preferably 1.5 mm to 45 mm, even more preferably 2.0 mm to 40 mm, and particularly preferably 2.5 mm to 35 mm. By keeping it within this range, it becomes easier to position cutting means such as cutters in the uneven region R and to perform cutting, while also allowing for the desirable realization of various advantages of the uneven region R while ensuring a large amount of flat region F. 【0024】 Furthermore, from the viewpoint of ensuring a sufficient area (i.e., a flat area F) in the metal layer 18 that can provide the flatness necessary for forming a fine pattern, it is preferable that the ratio of the area of ​​the uneven area R to the total area of ​​the flat area F and the uneven area R of the carrier 12 is 0.01 or more and 0.5 or less, more preferably 0.02 or more and 0.45 or less, even more preferably 0.05 or more and 0.40 or less, and particularly preferably 0.1 or more and 0.35 or less. 【0025】 The optional intermediate layer 14 is interposed between the carrier 12 and the release layer 16, contributing to ensuring adhesion between the carrier 12 and the release layer 16. Examples of metals constituting the intermediate layer 14 include Cu, Ti, Al, Nb, Zr, Cr, W, Ta, Co, Ag, Ni, In, Sn, Zn, Ga, Mo, and combinations thereof (hereinafter referred to as metal M), preferably Cu, Ti, Al, Nb, Zr, Cr, W, Ta, Co, Ag, Ni, Mo, and combinations thereof, more preferably Cu, Ti, Zr, Al, Cr, W, Ni, Mo, and combinations thereof, even more preferably Cu, Ti, Al, Cr, Ni, Mo, and combinations thereof, and particularly preferably Cu, Ti, Al, Ni, and combinations thereof. The intermediate layer 14 may be a pure metal or an alloy. The metal constituting the intermediate layer 14 may contain unavoidable impurities resulting from the raw material components or the film formation process. Furthermore, although not particularly limited, the presence of oxygen mixed in when the intermediate layer 14 is exposed to the atmosphere after film formation is acceptable. The upper limit of the metal content is not particularly limited and may be 100 atomic percent. The intermediate layer 14 is preferably a layer formed by physical vapor deposition (PVD), and more preferably a layer formed by sputtering. From the viewpoint of uniformity of film thickness distribution, the intermediate layer 14 is particularly preferably a layer formed by magnetron sputtering using a metal target. The thickness of the intermediate layer 14 is preferably 10 nm to 1000 nm, more preferably 30 nm to 800 nm, even more preferably 60 nm to 600 nm, and particularly preferably 100 nm to 400 nm. By setting such a thickness, it is possible to create an intermediate layer having a roughness equivalent to that of the carrier. This thickness is measured by analyzing the layer cross-section with an energy-dispersive X-ray spectrometer (TEM-EDX) on a transmission electron microscope. 【0026】 The intermediate layer 14 may be a single layer or a layer of two or more layers. When the intermediate layer 14 is a single layer, it is preferable that the intermediate layer 14 consists of a layer containing a metal composed of Cu, Al, Ti, Ni, or a combination thereof (e.g., alloys or intermetallic compounds), more preferably Al, Ti, or a combination thereof (e.g., alloys or intermetallic compounds), and even more preferably a layer mainly containing Al or a layer mainly containing Ti. On the other hand, when a metal or alloy that does not have sufficiently high adhesion to the carrier 12 is used for the intermediate layer 14, it is preferable to have a two-layer intermediate layer 14. That is, by providing a layer made of a metal (e.g., Ti) or alloy with excellent adhesion to the carrier 12 adjacent to the carrier 12, and providing a layer made of a metal (e.g., Cu) or alloy with poor adhesion to the carrier 12 adjacent to the release layer 16, the adhesion to the carrier 12 can be improved. Therefore, an example of a preferred two-layer intermediate layer 14 is a laminated structure consisting of a Ti-containing layer adjacent to the carrier 12 and a Cu-containing layer adjacent to the release layer 16. Furthermore, since changing the balance of constituent elements and thickness of each layer in the two-layer structure also changes the peel strength, it is preferable to appropriately adjust the constituent elements and thickness of each layer. In this specification, the category of "metal M-containing layer" includes alloys containing elements other than metal M, as long as they do not impair the carrier peelability. Therefore, the intermediate layer 14 can also be said to be a layer mainly containing metal M. From the above point of view, the metal M content in the intermediate layer 14 is preferably 50 atomic% or more and 100 atomic% or less, more preferably 60 atomic% or more and 100 atomic% or less, even more preferably 70 atomic% or more and 100 atomic% or less, particularly preferably 80 atomic% or more and 100 atomic% or less, and most preferably 90 atomic% or more and 100 atomic% or less. 【0027】 When the intermediate layer 14 is made of an alloy, a preferred example of an alloy is a Ni alloy. The Ni alloy preferably has a Ni content of 45% to 98% by weight, more preferably 55% to 90% by weight, and even more preferably 65% ​​to 85% by weight. A preferred Ni alloy is an alloy of Ni and at least one selected from the group consisting of Cr, W, Ta, Co, Cu, Ti, Zr, Si, C, Nd, Nb, and La, and more preferably an alloy of Ni and at least one selected from the group consisting of Cr, W, Cu, and Si. When the intermediate layer 14 is a Ni alloy layer, it is particularly preferable from the viewpoint of uniformity of film thickness distribution that the layer is formed by a magnetron sputtering method using a Ni alloy target. 【0028】 The release layer 16 is a layer that enables or facilitates the release of the carrier 12 and, if present, the intermediate layer 14. The release layer 16 may be either an organic release layer or an inorganic release layer. Examples of organic components used in the organic release layer include nitrogen-containing organic compounds, sulfur-containing organic compounds, and carboxylic acids. Examples of nitrogen-containing organic compounds include triazole compounds and imidazole compounds. On the other hand, examples of inorganic components used in the inorganic release layer include metal oxides or metal oxynitrides containing at least one of Ni, Mo, Co, Cr, Fe, Ti, W, P, Zn, Cu, Al, Nb, Zr, Ta, Ag, In, Sn, and Ga, or a carbon layer. In particular, the release layer 16 is preferably a carbon-containing layer, i.e., a layer mainly containing carbon, from the viewpoint of ease of release and film formation, more preferably a layer mainly consisting of carbon or hydrocarbons, and even more preferably a layer made of amorphous carbon, which is a hard carbon film. In this case, the carbon concentration of the release layer 16 (i.e., the carbon-containing layer) measured by XPS is preferably 60 atomic percent or more, more preferably 70 atomic percent or more, even more preferably 80 atomic percent or more, and particularly preferably 85 atomic percent or more. The upper limit of the carbon concentration is not particularly limited and may be 100 atomic percent, but 98 atomic percent or less is practical. The release layer 16 may contain unavoidable impurities (e.g., oxygen, hydrogen, etc., originating from the surrounding environment such as the atmosphere). In addition, metal atoms of types other than the metal contained in the release layer 16 may be mixed into the release layer 16 due to the film formation method of the functional layer 17 or the metal layer 18. When a carbon-containing layer is used as the release layer 16, the interdiffusion and reactivity with carriers are low, and even when subjected to press processing at temperatures exceeding 300°C, the formation of metallic bonds due to high-temperature heating between the metal layer and the bonding interface can be prevented, and a state in which carrier peeling and removal is easy can be maintained. It is preferable that the release layer 16 is also formed by a vapor phase method such as sputtering, in order to suppress excessive impurities in the release layer 16 and to enable continuous production with the formation of the optional intermediate layer 14. When a carbon-containing layer is used as the release layer 16, its thickness is preferably 1 nm to 20 nm, and more preferably 1 nm to 10 nm.By achieving this thickness, it becomes possible to create a delamination layer that has a roughness equivalent to that of the carrier and possesses delamination functionality. This thickness is measured by analyzing the cross-section of the layer with an energy-dispersive X-ray spectrometer (TEM-EDX) on a transmission electron microscope. 【0029】 The release layer 16 may include a metal oxide layer and a carbon-containing layer, or it may be a layer containing both metal oxide and carbon. In particular, when the carrier-attached metal foil 10 includes an intermediate layer 14, the carbon-containing layer contributes to the stable release of the carrier 12, and the metal oxide layer can suppress the diffusion of metal elements originating from the intermediate layer 14 and the metal layer 18 during heating. As a result, stable release properties can be maintained even after heating at high temperatures, such as 350°C or higher. The metal oxide layer is preferably a layer containing an oxide of a metal composed of Cu, Ti, Al, Nb, Zr, Cr, W, Ta, Co, Ag, Ni, In, Sn, Zn, Ga, Mo, or a combination thereof. The metal oxide layer is preferably formed by a reactive sputtering method using a metal target and sputtering in an oxidizing atmosphere, as the film thickness can be easily controlled by adjusting the film formation time. The thickness of the metal oxide layer is preferably 0.1 nm to 100 nm. The upper limit of the thickness of the metal oxide layer is more preferably 60 nm or less, even more preferably 30 nm or less, and particularly preferably 10 nm or less. This thickness is measured by analyzing the cross-section of the layer with an energy-dispersive X-ray spectrometer (TEM-EDX) on a transmission electron microscope. In this case, the order in which the metal oxide layer and the carbon layer are stacked as the release layer 16 is not particularly limited. Furthermore, the release layer 16 may exist in a multiphase state (i.e., a layer containing both metal oxide and carbon) where the boundary between the metal oxide layer and the carbon-containing layer is not clearly defined. 【0030】 Similarly, from the viewpoint of maintaining stable release properties even after heat treatment at high temperatures, the release layer 16 may be a metal-containing layer whose surface adjacent to the metal layer 18 is a fluorinated surface and / or a nitrided surface. Preferably, the metal-containing layer has a region (hereinafter referred to as the "(F+N) region") over a thickness of 10 nm or more in which the sum of the fluorine content and nitrogen content is 1.0 atomic% or more, and the (F+N) region is preferably located on the metal layer 18 side of the metal-containing layer. The thickness of the (F+N) region (in terms of SiO2) is determined by performing depth-direction elemental analysis of the carrier-attached metal foil 10 using XPS. The fluorinated surface or nitrided surface can preferably be formed by reactive ion etching (RIE) or reactive sputtering. On the other hand, it is preferable that the metal elements contained in the metal-containing layer have a negative standard electrode potential. Preferred examples of metal elements included in the metal-containing layer include Cu, Ag, Sn, Zn, Ti, Al, Nb, Zr, W, Ta, Mo, and combinations thereof (e.g., alloys and intermetallic compounds). The metal element content in the metal-containing layer is preferably 50 atomic% to 100 atomic%. The metal-containing layer may be a single layer or a multilayer composed of two or more layers. The overall thickness of the metal-containing layer is preferably 10 nm to 1000 nm, more preferably 30 nm to 500 nm, even more preferably 50 nm to 400 nm, and particularly preferably 100 nm to 300 nm. The thickness of the metal-containing layer itself is measured by analyzing the cross-section of the layer with an energy-dispersive X-ray spectrometer (TEM-EDX) on a transmission electron microscope. 【0031】 Alternatively, the release layer 16 may be a metal oxynitride-containing layer instead of a carbon layer or the like. The surface of the metal oxynitride-containing layer opposite to the carrier 12 (i.e., the metal layer 18 side) preferably contains at least one metal oxynitride selected from the group consisting of TaON, NiON, TiON, NiWON, and MoON. Furthermore, in order to ensure adhesion between the carrier 12 and the metal layer 18, the surface of the metal oxynitride-containing layer on the carrier 12 side preferably contains at least one selected from the group consisting of Cu, Ti, Ta, Cr, Ni, Al, Mo, Zn, W, TiN, and TaN. This suppresses the number of foreign particles on the surface of the metal layer 18, improves circuit formation, and makes it possible to maintain stable release strength even after heating at high temperatures for a long time. The thickness of the metal oxynitride-containing layer is preferably 5 nm to 500 nm, more preferably 10 nm to 400 nm, even more preferably 20 nm to 200 nm, and particularly preferably 30 nm to 100 nm. This thickness is determined by analyzing the layer cross-section using an energy-dispersive X-ray spectrometer (TEM-EDX) on a transmission electron microscope. 【0032】 A functional layer 17 may be provided between the release layer 16 and the metal layer 18 if desired. The functional layer 17 is not particularly limited as long as it imparts a desired function to the carrier-attached metal foil 10, such as an etching stopper function or an anti-reflective function. Preferred examples of metals constituting the functional layer 17 include Ti, Al, Nb, Zr, Cr, W, Ta, Co, Ag, Ni, Mo and combinations thereof, more preferably Ti, Zr, Al, Cr, W, Ni, Mo and combinations thereof, even more preferably Ti, Al, Cr, Ni, Mo and combinations thereof, and particularly preferably Ti, Mo and combinations thereof. These elements have the property of not dissolving in flash etching solutions (e.g., copper flash etching solutions), and as a result can exhibit excellent chemical resistance to flash etching solutions. Therefore, the functional layer 17 is less susceptible to etching by flash etching solutions than the metal layer 18, and thus can function as an etching stopper layer. Furthermore, since the metal constituting the functional layer 17 also has the function of preventing light reflection, the functional layer 17 can also function as an anti-reflective layer to improve visibility in image inspection (e.g., automated image inspection (AOI)). The functional layer 17 may be a pure metal or an alloy. The metal constituting the functional layer 17 may contain unavoidable impurities resulting from the raw material components or the film formation process. Also, there is no particular upper limit to the content of the above metal, and it may be 100 atomic percent. The functional layer 17 is preferably a layer formed by physical vapor deposition (PVD), and more preferably a layer formed by sputtering. The thickness of the functional layer 17 is preferably 1 nm to 500 nm, more preferably 10 nm to 400 nm, even more preferably 30 nm to 300 nm, and particularly preferably 50 nm to 200 nm. 【0033】 The metal layer 18 is a layer composed of metal. Preferred examples of metals constituting the metal layer include Cu, Au, Pt, and combinations thereof (e.g., alloys and intermetallic compounds), more preferably Cu, Au, Pt, and combinations thereof, and even more preferably Cu. The metal constituting the metal layer 18 may contain unavoidable impurities resulting from the raw material components or the film formation process. The metal layer 18 may be manufactured by any method, for example, a metal layer formed by wet film formation methods such as electroless metal plating and electrolytic metal plating, physical vapor deposition (PVD) methods such as sputtering and vacuum deposition, chemical vapor deposition, or a combination thereof. Particularly preferred is a metal layer formed by physical vapor deposition (PVD) methods such as sputtering or vacuum deposition, from the viewpoint of easily accommodating fine pitch reduction through ultrathinning, and most preferably a metal layer manufactured by sputtering. Furthermore, while it is preferable that the metal layer 18 is an unroughened metal layer, it may also be a metal layer that has undergone secondary roughening by preliminary roughening, soft etching, cleaning, or oxidation-reduction treatment, as long as it does not interfere with the formation of the wiring pattern during the manufacturing of the printed circuit board. From the viewpoint of accommodating the fine pitch described above, the thickness of the metal layer 18 is 0.01 μm to 4.0 μm, preferably 0.02 μm to 3.0 μm, more preferably 0.05 μm to 2.5 μm, even more preferably 0.10 μm to 2.0 μm, particularly preferably 0.20 μm to 1.5 μm, and most preferably 0.30 μm to 1.2 μm. Metal layers 18 with a thickness within this range are preferably manufactured by sputtering in order to maintain in-plane uniformity of the film thickness and to improve productivity in sheet or roll form. 【0034】 Preferably, the outermost surface of the metal layer 18 has a flat shape corresponding to the surface shape of the flat region F of the carrier 12 and an uneven shape corresponding to the surface shape of the uneven region R of the carrier 12. That is, as shown in Figures 1 and 2, the metal layer 18 is formed on the carrier 12 having the flat region F and the uneven region R via an intermediate layer 14 (if present), a release layer 16, and a functional layer 17 (if present), thereby transferring the surface profiles of the flat region F and the uneven region R of the carrier 12 to the surface of each layer, respectively. In this way, it is preferable that the uneven shape is transferred to a part of the release layer 16, while a desirable surface profile corresponding to the shape of each region of the carrier 12 is given to the outermost surface of the metal layer 18. This further prevents peeling of the metal layer 18 when the carrier-attached metal foil 10 is cut, and also allows for finer pitch. Typically, the flat surfaces on the outermost surface of the metal layer 18 that correspond to the flat region F of the carrier 12 (i.e., flat surfaces) have an interface development area ratio Sdr of less than 5%, preferably 0.01% to 4.0%, more preferably 0.03% to 3.0%, even more preferably 0.05% to 1.0%, and particularly preferably 0.08% to 0.50%. Also, the uneven surfaces on the outermost surface of the metal layer 18 that correspond to the uneven region R of the carrier 12 (i.e., uneven surfaces) typically have an interface development area ratio Sdr of 5% to 39%, preferably 6% to 36%, more preferably 7% to 32%, even more preferably 7% to 25%, and particularly preferably 8% to 22%. 【0035】 The intermediate layer 14 (if present), the release layer 16, the functional layer 17 (if present), and the metal layer 18 are preferably all physical vapor deposition (PVD) films, i.e., films formed by the physical vapor deposition (PVD) method, and more preferably sputtered films, i.e., films formed by the sputtering method. 【0036】 The overall thickness of the carrier-attached metal foil 10 is not particularly limited, but is preferably 500 μm to 3000 μm, more preferably 700 μm to 2500 μm, even more preferably 900 μm to 2000 μm, and particularly preferably 1000 μm to 1700 μm. The size of the carrier-attached metal foil 10 is not particularly limited, but is preferably 10 cm square or larger, more preferably 20 cm square or larger, and even more preferably 25 cm square or larger. There is no particular upper limit to the size of the carrier-attached metal foil 10, but 1000 cm square is one guideline for the upper limit. Furthermore, the carrier-attached metal foil 10 is in a form that can be handled independently before and after the formation of the wiring. 【0037】 Manufacturing method for metal foil with carrier The carrier-attached metal foil 10 of the present invention can be manufactured by (1) preparing a carrier, (2) roughening at least the outer periphery of the carrier surface, and (3) forming various layers such as a release layer and a metal layer on the carrier. 【0038】 (1) Career preparation First, a carrier 12 is prepared, which is a flat surface with an interface development area ratio Sdr of less than 5% on at least one of its surfaces. The interface development area ratio Sdr is preferably 0.01% to 4.0%, more preferably 0.03% to 3.0%, even more preferably 0.05% to 1.0%, particularly preferably 0.07% to 0.50%, and most preferably 0.08% to 0.50%. Generally, substrates and plate-shaped glass products made of SiO2, SiN, Si single crystal, and Si polycrystalline have excellent flatness, so commercially available SiO2 substrates, SiN substrates, Si single crystal substrates, Si polycrystalline substrates, glass sheets, glass films, and glass plates having a flat surface that satisfies the above range of Sdr may be used as the carrier 12. Alternatively, the surface of the carrier 12 that does not satisfy the above Sdr may be polished using a known method to impart an Sdr within the above range. The preferred material and properties of the carrier 12 are as described above. 【0039】 (2) Roughening treatment of the carrier surface Next, a roughening treatment is performed on at least the outer periphery of the surface of the carrier 12 to form a linear pattern of uneven regions R with an interface development area ratio Sdr of 5% or more and 39% or less. The interface development area ratio Sdr is preferably 6% or more and 36% or less, more preferably 7% or more and 32% or less, even more preferably 7% or more and 25% or less, and particularly preferably 8% or more and 22% or less. Furthermore, it is preferable to perform the roughening treatment on a predetermined area of ​​the surface of the carrier 12 such that the uneven regions form a linear pattern that divides multiple regions. The roughening treatment can be performed according to known methods and is not particularly limited as long as it can achieve an interface development area ratio Sdr within the above range and (using masking as necessary) can form the uneven regions R in the desired pattern. Preferred roughening treatment methods are blasting or etching, more preferably blasting, as they can efficiently form uneven regions R with the desired Sdr. 【0040】 The roughening treatment by blasting can be performed by projecting particulate media (projection material) from a nozzle onto the outer periphery or a predetermined area (i.e., the area where the uneven area R should be formed) of the surface of the carrier 12. The preferred nozzle size is 0.1 mm to 20 mm in width and 100 mm to 1000 mm in length when the discharge port is rectangular, and more preferably 3 mm to 15 mm in width and 200 mm to 800 mm in length. On the other hand, when the discharge port is circular, the preferred nozzle size is 0.2 mm to 50 mm in diameter, and more preferably 3 mm to 20 mm in diameter. The particle size of the media is preferably 7 μm to 50 μm, and more preferably 8 μm to 35 μm. Preferred examples of media materials include alumina, zirconia, silicon carbide, iron, aluminum, zinc, glass, steel, and boron carbide. The Mohs hardness of the media is preferably 4 or higher, more preferably 5.5 or higher, and even more preferably 6.0 or higher. In particular, by using such media, it is possible to form an uneven region R on the surface of the carrier 12 in which the desired Sdr is controlled within the above range. The preferred media discharge pressure is 0.01 MPa to 0.80 MPa, more preferably 0.1 MPa to 0.50 MPa, and even more preferably 0.15 MPa to 0.25 MPa. The blasting time per unit area of ​​the carrier 12 is 0.03 seconds / cm². 2 More than 10 seconds / cm 2 Preferably, it is less than or equal to 0.1 seconds / cm. 2 More than 5 seconds / cm 2 The following is preferable. In particular, it is preferable to mix the media with water to form a slurry and then discharge this slurry from a nozzle using pressurized air to perform blasting, as this makes it easier to form an uneven region R on the surface of the carrier 12 in which Sdr is controlled within the above range. Furthermore, by performing roughening treatment (blasting treatment) under the above conditions, the decrease in the strength of the carrier after roughening treatment can be suppressed more effectively. 【0041】 From this perspective, the roughening treatment (e.g., blasting) of the surface of the carrier 12 is preferably performed under conditions such that, when the roughening treatment is performed on a frame-shaped region with a width of 11 mm that constitutes the outer periphery of the surface of the 300 mm square untreated carrier, the average breaking load of the roughened carrier is 61% to 120% of the average breaking load of the untreated carrier, more preferably 63% to 110%, and even more preferably 70% to 100%. However, the 300 mm square untreated carrier is the same as the carrier 12 prepared in (1) above, except that it does not have an uneven region R, and its planar shape and / or size may be different. 【0042】 On the other hand, preferred examples of roughening treatment by etching include a wet process using a solution containing hydrofluoric acid (hydrofluoric acid), and a dry process using reactive ion etching (RIE) with a fluorine-containing process gas (e.g., CF4 or SF6). 【0043】 It is preferable to use masking to selectively roughen (particularly blast or etch) a desired area. Specifically, as shown in Figure 5, it is preferable to form a masking layer 20 on the surface of the carrier 12 other than a predetermined area (i.e., the area where the uneven area R should be formed) before the roughening treatment. In this case, it is desirable to remove the masking layer 20 after the roughening treatment. 【0044】 (3) Formation of various layers on the carrier On the roughened carrier 12, an intermediate layer 14, a release layer 16, a functional layer 17, and a metal layer 18 with a thickness of 0.01 μm to 4.0 μm are optionally formed. The formation of each layer, the intermediate layer 14 (if present), the release layer 16, the functional layer 17 (if present), and the metal layer 18, is preferably carried out by physical vapor deposition (PVD) from the viewpoint of easily accommodating fine pitch reduction through ultrathinning. Examples of physical vapor deposition (PVD) methods include sputtering, vacuum deposition, and ion plating, but sputtering is the most preferred method because it allows for film thickness control over a wide range of 0.05 nm to 5000 nm and ensures film thickness uniformity over a wide width or area. In particular, by forming all layers, including the intermediate layer 14 (if present), the release layer 16, the functional layer 17 (if present), and the metal layer 18, by sputtering, manufacturing efficiency is significantly increased. The deposition of films by physical vapor deposition (PVD) is not particularly limited and can be carried out using known vapor deposition apparatus and under known conditions. For example, when using the sputtering method, various known sputtering methods such as magnetron sputtering, two-pole sputtering, and opposing target sputtering may be used, but magnetron sputtering is preferred because it has a high deposition rate and high productivity. Sputtering may be performed using either DC (direct current) or RF (radio frequency) power supplies. In addition, a widely known plate-type target can be used as the target shape, but it is desirable to use a cylindrical target from the viewpoint of target utilization efficiency. The deposition of each layer, the intermediate layer 14, the release layer 16 (in the case of a carbon-containing layer), the functional layer 17, and the metal layer 18, by physical vapor deposition (PVD) (preferably by sputtering) will be described below. 【0045】 The film formation of the intermediate layer 14 by physical vapor deposition (PVD) method (preferably sputtering method) is preferably performed by magnetron sputtering in a non-oxidizing atmosphere using a target composed of at least one metal selected from the group consisting of Cu, Ti, Al, Nb, Zr, Cr, W, Ta, Co, Ag, Ni, In, Sn, Zn, Ga, and Mo, in terms of improving the film thickness distribution uniformity. The purity of the target is preferably 99.9% or more. As the gas used for sputtering, an inert gas such as argon gas is preferably used. The flow rate of argon gas may be appropriately determined according to the sputtering chamber size and film formation conditions and is not particularly limited. Also, from the viewpoint of continuously forming a film without operational failures such as abnormal discharge and poor plasma irradiation, the pressure during film formation is preferably in the range of 0.1 Pa or more and 20 Pa or less. This pressure range may be set by adjusting the film formation power and the flow rate of argon gas according to the device structure, capacity, exhaust capacity of the vacuum pump, rated capacity of the film formation power supply, etc. Also, the sputtering power may be appropriately set within the range of 0.05 W / cm 2 or more and 10.0 W / cm 2 or less per unit area of the target in consideration of film thickness uniformity and productivity of film formation. 【0046】 The film formation of the release layer 16 by physical vapor deposition (PVD) method (preferably sputtering method) is preferably performed in an inert atmosphere such as argon using a carbon target. The carbon target is preferably composed of graphite, but may contain inevitable impurities (for example, oxygen and carbon derived from the surrounding environment such as the atmosphere). The purity of the carbon target is preferably 99.99% or more, more preferably 99.999% or more. Also, from the viewpoint of continuously forming a film without operational failures such as abnormal discharge and poor plasma irradiation, the pressure during film formation is preferably in the range of 0.1 Pa or more and 2.0 Pa or less. This pressure range may be set by adjusting the film formation power and the flow rate of argon gas according to the device structure, capacity, exhaust capacity of the vacuum pump, rated capacity of the film formation power supply, etc. Also, the sputtering power may be appropriately set within the range of 0.05 W / cm 2 or more and 10.0 W / cm 2You can set it as appropriate within the following range. 【0047】 The deposition of the functional layer 17 by physical vapor deposition (PVD) (preferably sputtering) is preferably carried out by magnetron sputtering using a target composed of at least one metal selected from the group consisting of Ti, Al, Nb, Zr, Cr, W, Ta, Co, Ag, Ni, and Mo. The purity of the target is preferably 99.9% or higher. In particular, the deposition of the functional layer 17 by magnetron sputtering is preferably carried out under an inert gas atmosphere such as argon, at a pressure of 0.1 Pa to 20 Pa. The sputtering pressure is more preferably 0.2 Pa to 15 Pa, and even more preferably 0.3 Pa to 10 Pa. The above pressure range can be controlled by adjusting the deposition power and argon gas flow rate according to the apparatus structure, capacity, vacuum pump exhaust capacity, rated capacity of the deposition power supply, etc. The argon gas flow rate is not particularly limited and can be appropriately determined according to the sputtering chamber size and deposition conditions. Furthermore, considering factors such as film thickness uniformity and productivity, the sputtering power should be 1.0 W / cm² per unit area of ​​the target. 2 More than 15.0W / cm 2 The temperature can be set appropriately within the following range. Furthermore, maintaining a constant carrier temperature during film formation is preferable in that it is easier to obtain stable film characteristics (e.g., film resistance and crystal size). The carrier temperature during film formation is preferably adjusted within the range of 25°C to 300°C, more preferably 40°C to 200°C, and even more preferably 50°C to 150°C. 【0048】 The deposition of the metal layer 18 by physical vapor deposition (PVD) (preferably sputtering) is preferably carried out under an inert atmosphere such as argon, using a target composed of at least one metal selected from the group consisting of Cu, Au, and Pt. The target is preferably composed of a pure metal or an alloy, but may contain unavoidable impurities. The purity of the target is preferably 99.9% or higher, more preferably 99.99%, and even more preferably 99.999% or higher. To avoid temperature rise during vapor deposition of the metal layer 18, a cooling mechanism for the stage may be provided during sputtering. Furthermore, from the viewpoint of stable deposition without malfunctions such as abnormal discharge or plasma irradiation failure, the deposition pressure is preferably in the range of 0.1 Pa to 2.0 Pa. This pressure range can be set by adjusting the deposition power and argon gas flow rate according to the apparatus structure, capacity, vacuum pump exhaust capacity, rated capacity of the deposition power supply, etc. The sputtering power should be 0.05 W / cm² per unit area of ​​the target, taking into consideration the uniformity of the film thickness and productivity of the deposition. 2 More than 10.0W / cm 2 You can set it as appropriate within the following range. [Examples] 【0049】 The present invention will be further explained by the following examples. 【0050】 The interface area ratio Sdr mentioned in the following example was measured using a laser microscope (Olympus Corporation, OLS5000) in accordance with ISO 25178. Specifically, the measurement was performed on a surface area of ​​12690 μm². 2 The surface profile of the region was measured using the laser microscope described above with a 100x lens with a numerical aperture (NA) of 0.95. After noise reduction and first-order linear surface tilt correction were performed on the obtained surface profile, the interface development area ratio Sdr was measured by surface property analysis. At this time, no cutoff was performed using S filters or L filters for the Sdr measurement. 【0051】 Example A1 As shown in Figure 1, a glass carrier was prepared as carrier 12. After forming an uneven region R on this glass carrier, an intermediate layer 14 (Ti-containing layer and Cu-containing layer), a carbon-containing layer as a release layer 16, a functional layer 17, and a metal layer 18 were deposited in this order to produce a carrier-attached metal foil 10. The specific procedure is as follows. 【0052】 (1) Career preparation A 200mm x 250mm glass sheet with a thickness of 1.1mm (material: soda-lime glass, manufactured by Central Glass Co., Ltd.) was prepared, having a flat surface with an interface development area ratio Sdr of 0.10%. 【0053】 (2) Carrier roughening treatment As shown in Figure 5, a masking layer 20 was formed on the surface of the carrier 12 in a pattern of four rectangular masking regions spaced apart from each other with an average line width of 2.5 mm. This masking layer 20 was formed by roll lamination using adhesive PVC tape (Lintec Corporation, PVC100M M11K). Next, using a blasting device (Fuji Seisakusho Co., Ltd., part number: SCM-4RBT-05-401), a medium (alumina) with an average particle size of 20 μm was projected onto the partially masked surface of the carrier 12 from a nozzle with a width of 3 mm and a length of 630 mm (the length of the part overlapping with the carrier 12 in a plan view is 200 mm) at a discharge pressure of 0.1 MPa to 0.25 MPa, thereby roughening the exposed parts of the carrier 12. The blasting time per unit area of ​​the carrier 12 was 0.33 seconds / cm². 2 This was done. In this way, a grid-like pattern of uneven regions R with an average line width of 2.5 mm was formed on the surface of the carrier 12. After that, the masking layer 20 was removed to expose the flat regions F. 【0054】 (3) Formation of Ti-containing layer A 100 nm thick Ti layer was formed on the roughened surface of carrier 12 by sputtering using the following apparatus and conditions. - Equipment: Single-wafer magnetron sputtering system (Canon Tokki Corporation, MLS464) - Target: 8-inch (203.2mm) diameter Ti target (99.999% purity) - Ultimate vacuum: 1×10 -4 Less than Pa - Carrier gas: Ar (flow rate: 100 sccm) - Sputtering pressure: 0.35 Pa - Sputtering power: 1000W (3.1W / cm²) 2 ) - Temperature during film formation: 40℃ 【0055】 (4) Formation of Cu-containing layer A 100 nm thick Cu layer was formed on the Ti-containing layer by sputtering using the following apparatus and conditions. - Equipment: Single-wafer DC sputtering system (Canon Tokki Corporation, MLS464) - Target: 8-inch (203.2mm) diameter Cu target (99.98% purity) - Ultimate vacuum: 1×10 -4 Less than Pa - Carrier gas: Ar (flow rate: 100 sccm) - Sputtering pressure: 0.35 Pa - Sputtering power: 1000W (6.2W / cm²) 2 ) - Temperature during film formation: 40℃ 【0056】 (5) Formation of a carbon-containing layer An amorphous carbon layer with a thickness of 6 nm was formed on the Cu-containing layer as a release layer 16 by sputtering using the following apparatus and conditions. - Equipment: Single-wafer DC sputtering system (Canon Tokki Corporation, MLS464) - Target: 8-inch (203.2 mm) diameter carbon target (99.999% purity) - Ultimate vacuum: 1×10 -4 Less than Pa - Carrier gas: Ar (flow rate: 100 sccm) - Sputtering pressure: 0.35 Pa - Sputtering power: 250W (0.7W / cm²) 2 ) - Temperature during film formation: 40℃ 【0057】 (6) Formation of functional layer A Ti layer with a thickness of 100 nm was formed on the surface of the release layer 16 as a functional layer 17 by sputtering using the following apparatus and conditions. - Equipment: Single-wafer DC sputtering system (Canon Tokki Corporation, MLS464) - Target: 8-inch (203.2mm) diameter Ti target (99.999% purity) - Carrier gas: Ar (flow rate: 100 sccm) - Ultimate vacuum: 1×10 -4 Less than Pa - Sputtering pressure: 0.35 Pa - Sputtering power: 1000W (3.1W / cm²) 2 ) 【0058】 (7) Formation of a metal layer A 300 nm thick Cu layer was formed on the functional layer 17 as a metal layer 18 by sputtering using the following apparatus and conditions to obtain a carrier-attached metal foil 10. - Equipment: Single-wafer DC sputtering system (Canon Tokki Corporation, MLS464) - Target: 8-inch (203.2mm) diameter Cu target (99.98% purity) - Ultimate vacuum: 1×10 -4 Less than Pa - Carrier gas: Ar (flow rate: 100 sccm) - Sputtering pressure: 0.35 Pa - Sputtering power: 1000W (3.1W / cm²) 2 ) - Temperature during film formation: 40℃ 【0059】 (8) Measurement of peel strength in uneven areas Except for not forming the masking layer 20, a carrier-attached metal foil was prepared in the same manner as in (1) to (7) above, with the entire surface of one side being an uneven region. 18 μm of Cu was laminated onto the metal layer side of this carrier-attached metal foil by electroplating to obtain a measurement sample. The peel strength (gf / cm) of the electroplated Cu layer was measured on this measurement sample in accordance with JIS Z 0237-2009, under conditions of a measurement width of 10 mm, a measurement length of 17 mm, and a peel speed of 50 mm / min. The measured peel strengths of the uneven regions are shown in Table 1. 【0060】 Examples A2~A15 Except for changing the blast treatment conditions appropriately during the carrier roughening process, which altered the unfolded area ratio Sdr of the interface R of the carrier 12, the carrier-attached metal foil 10 was manufactured in the same manner as in Example A1. The peel strength of the uneven region was also measured in the same manner as in Example A1. For Examples A2, A5, and A14, the media was mixed with water to form a slurry, and this slurry was discharged from a nozzle using pressurized air for blast treatment (wet blasting). 【0061】 evaluation For the metal foils 10 with glass as the carrier, as in Examples A1 to A15, a test was conducted to confirm the peelability at the edges during dicing. Specifically, using a commercially available dicing device, the metal foils 10 with the carrier were cut parallel to the linear pattern, passing through the center of the line width direction of the uneven region. At this time, the presence or degree of peeling of the metal layer 18 at the cut edges after dicing was observed and graded according to the following criteria. The evaluation results are shown in Table 1. In addition, Table 1 also shows the developed area ratio Sdr and peel strength of the interface in the uneven region R of the carrier 12. Evaluation A: No delamination of the metal layer was observed from the cut end. Evaluation B: Partial delamination of the metal layer was observed from the cut end. Evaluation C: Delamination was observed in most of the metal layer from the cut edge. Evaluation D: The metal layer had already spontaneously peeled off from the cut end before observation. 【0062】 [Table 1] 【0063】 Examples B1~B6 This example is an experimental case that verifies the relationship between the interface development area ratio Sdr and mechanical strength in a carrier. 【0064】 (1) Career preparation A 300mm square, 1.1mm thick glass sheet (material: soda-lime glass, manufactured by Nippon Sheet Glass Co., Ltd.) with a flat surface having an interface development area ratio Sdr of 0.10% was prepared. 【0065】 (2) Carrier roughening treatment A masking layer was formed on the surface of carrier 12, covering all areas except the perimeter (width 11 mm) of carrier 12. This masking layer was formed by cutting a cutting sheet (SPV-3620, manufactured by Nitto Denko Corporation) into 278 mm squares using a cutting plotter, and then laminating the cut cutting sheet onto the surface of carrier 12 so that the centers of the cutting sheet and the carrier overlapped. Next, using a blasting device (manufactured by Fuji Seisakusho Co., Ltd., part number: SCM-4RBT-05-401), media (alumina) of the grit shown in Table 2 was projected onto the partially masked surface of carrier 12 at the discharge pressure shown in Table 2 to roughen the exposed areas of carrier 12. In this way, an uneven region R was formed around the perimeter (width 11 mm) of carrier 12. After that, the masking layer was removed to expose the flat region F. In this example, the uneven region R is not provided in a pattern that demarcates multiple flat regions F, but it goes without saying that the uneven region of the above pattern can be formed on the carrier surface by appropriately changing the masking region. 【0066】 Example B7 (comparison) Without performing any roughening treatment on the carrier, the same sheet prepared in Examples B1-B6 was used as Carrier 12. 【0067】 evaluation For carriers 12 in Examples B1 to B7, the fracture load was measured using a universal material tester (Instron, part number: 5985). Specifically, as shown in Figures 6A and 6B, the carrier 12 was placed on eight support members S (made of S45C carbon steel for machine structures, hardened hardness: 50HRC, radius of curvature of contact portion: 5mm) arranged at equal intervals in a virtual circle with a diameter of 280mm. Then, the pressing member P (made of SUJ2 high-carbon chromium bearing steel, hardened hardness: 67HRC, radius of curvature of contact portion: 15mm) was moved in the direction of the arrow in Figure 6A and pressed against the center of the carrier 12, thereby fracturing the carrier 12. This measurement was performed on 10 carriers 12 for each example. From the obtained measurement data, a Weibull plot (X axis: fracture load (N), Y axis: cumulative fracture probability (%)) was created, and the average fracture load, 10% fracture load (B10), and shape parameter were calculated. The results are shown in Table 2. Table 2 also shows the percentage of the fracture load of the roughened glass carriers (Examples B1-B6) relative to the fracture load of the untreated glass carrier (Example B7). 【0068】 [Table 2]

Claims

[Claim 1] Career and, A release layer provided on the carrier, A metal layer with a thickness of 0.01 μm or more and 4.0 μm or less is provided on the aforementioned release layer, Equipped with, A metal foil with a carrier, wherein the carrier has, at least on the surface facing the metal layer, a single flat region where the interface area ratio Sdr measured in accordance with ISO 25178 is less than 5%, and an uneven region where the interface area ratio Sdr measured in accordance with ISO 25178 is 5% or more and 39% or less, and the uneven region is provided in a linear pattern surrounding the flat region. [Claim 2] The carrier-equipped metal foil according to claim 1, wherein the micro-Vickers hardness of the carrier is 500 HV or more and 3000 HV or less. [Claim 3] The metal foil with a carrier according to claim 1 or 2, wherein the outermost surface of the metal layer has a flat shape corresponding to the surface shape of the flat region of the carrier and an uneven shape corresponding to the surface shape of the uneven region of the carrier. [Claim 4] The carrier-equipped metal foil according to any one of claims 1 to 3, wherein the metal layer is composed of at least one metal selected from the group consisting of Cu, Au, and Pt. [Claim 5] A metal foil with a carrier according to any one of claims 1 to 4, further comprising an intermediate layer between the carrier and the release layer, the intermediate layer containing at least one metal selected from the group consisting of Cu, Ti, Al, Nb, Zr, Cr, W, Ta, Co, Ag, Ni, In, Sn, Zn, Ga, and Mo. [Claim 6] A carrier-equipped metal foil according to any one of claims 1 to 5, further comprising a functional layer between the release layer and the metal layer, the functional layer being composed of at least one metal selected from the group consisting of Ti, Al, Nb, Zr, Cr, W, Ta, Co, Ag, Ni, and Mo. [Claim 7] The carrier is SiO ２ A metal foil with a carrier according to any one of claims 1 to 6, wherein the glass contains glass. [Claim 8] The carrier-equipped metal foil according to any one of claims 1 to 7, wherein the carrier is composed of at least one type of glass selected from the group consisting of quartz glass, borosilicate glass, alkali-free glass, soda-lime glass, and aluminosilicate glass. [Claim 9] Metal foil with a carrier according to any one of claims 1 to 8, wherein the ratio of the area of ​​the uneven region to the total area of ​​the flat region and the uneven region of the carrier is 0.01 or more and 0.5 or less. [Claim 10] The carrier-attached metal foil according to any one of claims 1 to 9, wherein the peel strength of the carrier in the uneven region is 20 gf / cm or more and 3000 gf / cm or less. [Claim 11] A method for manufacturing a carrier-attached metal foil according to any one of claims 1 to 10, A step of preparing a carrier, wherein at least one surface is a flat surface with an interface development area ratio Sdr of less than 5% as measured in accordance with ISO 25178, A step of roughening the outer periphery of the surface of the carrier to form a linear pattern of uneven regions where the interface development area ratio Sdr, measured in accordance with ISO 25178, is 5% or more and 39% or less. The process of forming a release layer on the carrier, The process involves forming a metal layer with a thickness of 0.01 μm or more and 4.0 μm or less on the aforementioned release layer, A manufacturing method that includes this. [Claim 12] The roughening treatment is performed under conditions such that, when the roughening treatment is applied to a frame-shaped region with a width of 11 mm that constitutes the outer periphery of the surface of an untreated carrier measuring 300 mm square, the average breaking load of the roughened carrier becomes 61% to 120% of the average breaking load of the untreated carrier. The manufacturing method according to claim 11, wherein the 300 mm square untreated carrier is identical to the carrier except that it does not have the uneven region and its planar shape and / or size may be different. [Claim 13] The manufacturing method according to claim 11 or 12, wherein the roughening treatment is a blast treatment. [Claim 14] The blasting process includes projecting particulate media from a nozzle, The manufacturing method according to claim 13, wherein the media is provided in the form of a slurry, and the step of projecting the media is performed by using pressurized air to discharge the slurry from the nozzle. [Claim 15] The blasting time per unit area for the carrier is 0.03 seconds / cm². ２ 10 seconds / cm or more ２ The manufacturing method according to claim 13 or 14, which is as follows:

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