Method for manufacturing metal foil with carrier, laminate, and wiring board

Abstract

Provided is a carrier-attached metal foil that makes it possible to accurately perform positional alignment of a laminate after molding and thereby makes it possible to appropriately perform downsizing of the laminate. The carrier-attached metal foil comprises a carrier that has a first surface and a second surface, a peeling layer that is provided on the first surface, and a metal layer that is provided on the peeling layer, and has at least one alignment mark on or in the vicinity of the second surface of the carrier.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a carrier-attached metal foil, a laminate, and a wiring board.

Background Art

[0002] In recent years, in order to increase the mounting density and miniaturize printed wiring boards, multi-layered printed wiring boards have been widely used. Such multi-layer printed wiring boards are used in many portable electronic devices for the purpose of weight reduction and miniaturization. And for such multi-layer printed wiring boards, further reduction in the thickness of the interlayer insulating layer and further weight reduction as a wiring board are required.

[0003] As a technique for meeting such requirements, a method for manufacturing a multi-layer printed wiring board using a coreless build-up method has been adopted. The coreless build-up method is a method of alternately laminating (building up) an insulating layer and a wiring layer to form a multi-layer without using a so-called core substrate. In the coreless build-up method, it has been proposed to use a copper foil with a carrier so that the carrier can be easily peeled off from the support and the multi-layer printed wiring board. For example, Patent Document 1 (Japanese Patent Application Laid-Open No. 2005-101137) discloses a method for manufacturing a package substrate for mounting a semiconductor element, which includes attaching an insulating resin layer to the carrier surface of a copper foil with a carrier as a support, forming a first wiring conductor on the ultra-thin copper layer side of the copper foil with a carrier by processes such as photoresist processing, pattern electrolytic copper plating, and resist removal, then forming a build-up wiring layer, peeling off the carrier-attached support substrate, and removing the ultra-thin copper layer.

[0004] In addition, for the miniaturization of the embedded circuit as shown in Patent Document 1, a copper foil with a carrier having an ultra-thin copper layer with a thickness of 1 μm or less is desired. Therefore, in order to achieve a reduction in the thickness of the ultra-thin copper layer, it has been proposed to form the ultra-thin copper layer by a vapor phase method such as sputtering. For example, Patent Document 2 (International Publication No. 2017 / 150283) discloses a copper foil with a carrier in which a release layer, an antireflection layer, and an ultra-thin copper layer are formed by sputtering on a carrier such as glass or ceramics. Further, Patent Document 3 (International Publication No. 2017 / 150284) discloses a copper foil with a carrier in which an intermediate layer (for example, an adhesion metal layer and a release assisting layer), a release layer, and an ultra-thin copper layer (for example, a film thickness of 300 nm) are formed by sputtering on a carrier such as glass or ceramics. Patent Documents 2 and 3 teach that by interposing an intermediate layer composed of a predetermined metal, excellent stability of the mechanical peel strength of the carrier can be achieved, and by the antireflection layer exhibiting a desirable dark color, the visibility in image inspection (for example, automatic optical inspection (AOI)) can be improved.

[0005] In particular, with the further miniaturization and power saving of electronic devices, the need for higher integration and thinning of semiconductor chips and printed wiring boards is increasing. As next-generation packaging technologies to meet such needs, the adoption of FO-WLP (Fan-Out Wafer Level Packaging) and PLP (Panel Level Packaging) has been considered in recent years. And even in FO-WLP and PLP, the adoption of a coreless build-up method has been considered. As one such method, there is a method called the RDL-First (Redistribution Layer-First) method in which a wiring layer and, if necessary, a build-up wiring layer are formed on the surface of a coreless support, and after the support is peeled off if necessary, a chip is mounted. For example, Patent Document 4 (Japanese Unexamined Patent Application Publication No. 2015-35551) discloses the formation of a metal release layer on the main surface of a support made of glass or a silicon wafer, the formation of an insulating resin layer thereon, the formation of a redistribution layer including a build-up layer thereon, the mounting and sealing of a semiconductor integrated circuit thereon, the exposure of the release layer by removing the support, the exposure of secondary mounting pads by removing the release layer, the formation of solder bumps on the surface of the secondary mounting pads, and the manufacturing method of a semiconductor device including secondary mounting.

[0006] By the way, when forming a redistribution layer by a build-up method or the like on a carrier-attached metal foil, it has been proposed to perform alignment based on an alignment mark prior to exposure from the viewpoint of suppressing a decrease in yield and the like. For example, Patent Document 5 (Japanese Patent No. 7142774) discloses a carrier-attached metal foil having at least two positioning regions that form an alignment mark used for alignment during wiring formation involving exposure and development. According to Patent Document 5, by providing a processed portion that constitutes an alignment mark on the carrier itself, it is said that both exposure for a rough circuit and exposure for a fine circuit during wiring formation can be performed based on the same alignment mark.

Prior Art Documents

Patent Documents

[0007] Patent Document 1 Japanese Unexamined Patent Application Publication No. 2005-101137 Patent Document 2 International Publication No. 2017 / 150283 Patent Document 3 International Publication No. 2017 / 150284 Patent Document 4 Japanese Unexamined Patent Application Publication No. 2015-35551 Patent Document 5 Japanese Patent No. 7142774 Summary of the Invention

[0008] As a technology to meet the requirements of recent high-density mounting, there is a method called PoP (Package on Package) in which a plurality of IC packages are stacked and mounted on a substrate. According to PoP mounting, the integration density can be improved compared to the conventional mounting method in which IC packages are arranged two-dimensionally on a substrate. When adopting PoP mounting in the manufacture of a wiring board using a metal foil with a carrier, for example, after mounting a chip or the like on a wiring layer formed on the metal layer of the metal foil with a carrier and performing mold forming, a redistribution layer is formed on a resin-containing layer such as a mold resin layer, and it is conceivable to mount a further chip or the like on this redistribution layer. Here, in the process of forming the redistribution layer, since it is required to preliminarily adjust the substrate to a size corresponding to the standards of the apparatus, it may be necessary to perform downsizing on the laminate after mold forming. However, conventional metal foils with carriers cannot be said to sufficiently cope with such downsizing of the laminate after mold forming.

[0009] The inventors of the present invention have now found that by providing an alignment mark on the surface of the metal foil with a carrier opposite to the metal layer of the carrier, the alignment of the laminate after mold forming can be accurately performed, and therefore, the downsizing of the laminate can be appropriately performed.

[0010] Accordingly, an object of the present invention is to provide a metal foil with a carrier that can accurately align a laminate after mold forming, and thus can appropriately downsize the laminate.

[0011] According to the present invention, the following aspects are provided. [Aspect 1] A metal foil with a carrier comprising a carrier having a first surface and a second surface, a release layer provided on the first surface, and a metal layer provided on the release layer, The metal foil with a carrier, wherein the metal foil with a carrier has at least one alignment mark on the second surface of the carrier or in the vicinity thereof. [Aspect 2] The metal foil with a carrier according to Aspect 1, wherein the alignment mark has a shape capable of acquiring position information in the horizontal direction and the rotational direction on the second surface of the carrier. [Aspect 3] The metal foil with a carrier according to Aspect 1 or 2, wherein at least one of the alignment marks is located on the geometric center of the second surface of the carrier. [Aspect 4] The metal foil with a carrier according to any one of Aspects 1 to 3, wherein the alignment mark has at least one shape selected from the group consisting of a cross shape, a polygon, a star polygon, a circular shape, an elliptical shape, a character, and a symbol. [Aspect 5] The metal foil with a carrier according to any one of Aspects 1 to 4, wherein the carrier is composed of at least one selected from the group consisting of glass, silicon, ceramics, resin, and metal. [Aspect 6] The metal foil with a carrier according to any one of Aspects 1 to 5, wherein the alignment mark is formed by at least one selected from the group consisting of laser printing, laser engraving, gravure printing, flexographic printing, inkjet printing, silk printing, laser inner marking, and drilling. [Aspect 7] A laminate comprising the carrier-attached metal foil according to any one of Aspects 1 to 6 and a resin-containing layer provided on the metal layer. [Aspect 8] The laminate according to claim 7, wherein the resin-containing layer covers at least a part of the side surface of the carrier-attached metal foil, thereby having an extending portion extending outside the end surface of the carrier. [Aspect 9] The laminate according to Aspect 7 or 8, wherein the resin-containing layer embeds the entire part of the carrier-attached metal foil other than the second surface. [Aspect 10] The laminate according to any one of Aspects 7 to 9, wherein the resin-containing layer contains an insulating resin. [Aspect 11] A method for manufacturing a wiring board, comprising: a step of preparing a carrier-attached metal foil according to any one of Aspects 1 to 6; a step of forming a resin-containing layer on the metal layer of the carrier-attached metal foil, wherein the resin-containing layer is formed so as to cover at least a part of the side surface of the carrier-attached metal foil, thereby having an extending portion extending outside the end surface of the carrier; a step of performing positioning based on the alignment mark provided on the second surface of the carrier and cutting at least a part of the extending portion; A method for manufacturing a wiring board, including the above steps. [Aspect 12] The method for manufacturing a wiring board according to claim 11, wherein when the carrier-attached metal foil on which the resin-containing layer is formed is viewed in plan view, the cutting of the extending portion is performed so that the extending width of the portion extending from the end surface of the carrier in the resin-containing layer is 1.0 mm or less. [Aspect 13] The method for manufacturing a wiring board according to Aspect 11 or 12, further comprising a step of forming a rewiring layer on the surface of the resin-containing layer after cutting at least a part of the extending portion. [Aspect 14] The method for manufacturing a wiring board according to Aspect 12, further comprising a step of polishing the surface of the resin-containing layer before forming the rewiring layer. [Aspect 15] The manufacturing method of the wiring board according to any one of Aspects 11 to 14, wherein the resin-containing layer includes a wiring layer and an insulating layer. [Aspect 16] A cutting device for downsizing the laminate according to any one of Aspects 7 to 10, a fixing part for fixing the laminate, an identifying part for recognizing the alignment mark from the second surface side of the carrier with respect to the laminate fixed by the fixing part and specifying the position information of the laminate, a cutting part for cutting the side surface of the laminate whose position information has been specified by the identifying part. The cutting device having the above.

Brief Description of Drawings

[0012]

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Figure 2B

Figure 2C

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Figure 3B

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Figure 9

Embodiments for Carrying Out the Invention

[0013] Metal foil with carrier An example of the carrier-attached metal foil of the present invention is schematically shown in FIGS. 1 and 2. As shown in FIG. 1, the carrier-attached metal foil 10 includes a carrier 12, a release layer 16, and a metal layer 18 in this order. The carrier 12 has a first surface 12a and a second surface 12b. The release layer 16 is provided on the first surface 12a of the carrier. The metal layer 18 is provided on the release layer 16. Optionally, the carrier-attached metal foil 10 may further have an intermediate layer 14 between the carrier 12 and the release layer 16. Each of the intermediate layer 14, the release layer 16, and the metal layer 18 may be a single layer composed of one layer or a multilayer composed of two or more layers. As shown in FIGS. 2A to 2C, the carrier-attached metal foil 10 has at least one alignment mark AM on the second surface 12b of the carrier or in the vicinity thereof (hereinafter, may be simply referred to as "the second surface 12b of the carrier" or "the second surface 12b"). Thus, in the carrier-attached metal foil 10, by providing the alignment mark AM on the surface of the carrier 12 opposite to the metal layer 18 (that is, the second surface 12b), the alignment of the laminate after mold molding can be accurately performed, and therefore, the downsizing of the laminate can be appropriately performed.

[0014] As described above, in the production of a wiring board using a carrier-attached metal foil, it is possible to form a rewiring layer on a resin-containing layer such as a mold resin layer. And in the process of forming the rewiring layer, since it is required to preliminarily adjust the substrate to a size corresponding to the specifications of the apparatus, it may be necessary to perform downsizing on the laminate after mold forming. Specifically, due to the resin-containing layer extending from the end face of the carrier by mold forming (for example, full mold forming), the size of the laminate provided with the resin-containing layer becomes larger than the size of the original carrier-attached metal foil 10, and as a result, it may be necessary to cut off the extending portion of the resin-containing layer. Here, an example of downsizing the laminate after mold forming is shown in FIGS. 3A and 3B. FIGS. 3A and 3B are schematic bottom views of the laminate 20 provided with the resin-containing layer 22 as viewed from the second surface 12b side of the carrier. In this regard, as shown in FIG. 3A(i), it is typical to perform mold forming so that the resin-containing layer 22 extends uniformly from the end face (outer edge) of the carrier 12. However, as shown in FIG. 3B(i), an unintended misalignment (offset molding) may occur during mold forming, and the resin-containing layer 22 may extend non-uniformly from the end face of the carrier 12. And in any of the above cases, in order to proceed to the rewiring layer formation step, as shown in FIGS. 3A(ii) and 3B(ii), it is necessary to cut off the resin-containing layer 22 so that the length of the portion extending from the end face of the carrier 12 becomes equal to or less than a predetermined value, and downsize the laminate 20. Thus, in order to appropriately perform downsizing of the laminate 20 regardless of the accuracy of mold forming, it is desirable to align the laminate 20 using an alignment mark.

[0015] In this regard, the conventional metal foil with carrier disclosed in Patent Document 5 was not suitable for the alignment of the laminate after molding. That is, the conventional metal foil with carrier mainly used alignment marks for alignment performed prior to exposure during wiring formation, and provided alignment marks on the surface of the carrier on the metal layer side. Therefore, when the metal layer side etc. of the metal foil with carrier was embedded with a resin-containing layer by molding, it became impossible to identify the alignment marks any more. On the other hand, in the metal foil with carrier 10 of the present invention, since the alignment mark AM is provided on the surface opposite to the metal layer 18 of the carrier 12 (that is, the second surface 12b), even when the entire metal foil with carrier 10 other than the second surface 12b is embedded with a resin-containing layer, the alignment mark AM can be identified from the second surface 12b side. Therefore, the alignment of the laminate after molding can be accurately performed based on the alignment mark AM, and the downsizing of the laminate can be appropriately performed.

[0016] The number of alignment marks AM provided on the second side 12b of the carrier is at least one. However, the number and shape of the alignment marks AM are not particularly limited, and may be appropriately determined according to the specifications of a known position detection device (more specifically, the algorithm of a position detection program). Even if there is one alignment mark AM, when it is a position detection device capable of acquiring position information in the horizontal direction and the rotation direction on the second side 12b, the number of alignment marks AM is preferably one. On the other hand, in the case of a type of position detection device that reads a plurality of alignment marks AM and integrates their information to acquire position information in the horizontal direction and the rotation direction on the second side 12b, the number of alignment marks AM is preferably two or more. The upper limit of the number of alignment marks AM provided on the second side 12b of the carrier is not particularly limited, but is typically 200 or less, more typically 100 or less, and even more typically 50 or less. In any case, regardless of the shape and number of the alignment marks AM, if they match the shape and number of the alignment marks of the pattern pre-registered in the position detection device, the center position and angle of the carrier can be detected, and alignment can be performed with high accuracy. A preferred alignment mark AM is a case where it has a simple shape (for example, a cross shape, a polygon, a star polygon, a circle, an ellipse described later) and the number is one. By doing so, while the formation of the alignment mark is simple, the alignment of the laminate after mold forming can be performed with high accuracy. The metal foil 10 with a carrier preferably does not have an alignment mark on the first side 12a side of the carrier, so that the entire surface of the metal layer 18 can be used for wiring formation.

[0017] At least one of the alignment marks AM is preferably located on the geometric center (center of gravity) on the second side 12b of the carrier, as shown in FIG. 2A. By doing so, as shown in FIG. 2B, it becomes easier for the position detection device to find the position of the alignment mark AM than when the alignment mark AM is located at a random location (a location other than the geometric center) on the second side 12b of the carrier, and the alignment process can proceed more smoothly.

[0018] The alignment mark AM can basically have any shape, but typically has a shape that can acquire horizontal and rotational position information on the second surface 12b of the carrier, and preferably has a shape that facilitates the acquisition of horizontal and rotational position information. By having such a shape, it becomes possible to more reliably calculate the amount of positional deviation in the horizontal direction (xy direction) and the rotational direction (θ direction) from the original position during alignment, and alignment can be performed with even higher precision.

[0019] Examples of preferred shapes of the alignment mark AM include a cross (see FIG. 2A), a polygon, a star polygon (see FIG. 2B), a circle (see FIG. 2C), an ellipse, a character, a symbol, and combinations thereof, but are not limited thereto. Positioning is generally performed by a contour search (geometric shape search) that includes detecting the edges from the contour of the alignment mark and specifying the position of the center point of the alignment mark. When the alignment mark AM has the above shape, it becomes possible to reduce the error in specifying the center point and perform alignment with even higher precision.

[0020] The alignment mark AM is provided on or near the second surface 12b of the carrier. In the present invention, the vicinity of the second surface 12b means a position where the alignment mark can be optically read from the side of the second surface 12b of the carrier (for example, a position where the alignment mark can be imaged by imaging means such as a CCD camera). The alignment mark AM only needs to be capable of being imaged by imaging means from the side of the second surface 12b of the carrier as described above and its shape can be recognized by image processing, and its formation method is not particularly limited. For example, the alignment mark AM is preferably formed by laser printing, laser engraving, gravure printing, flexographic printing, inkjet printing, silk printing, laser inner marking, punching or a combination thereof, and more preferably laser engraving, laser inner marking or a combination thereof. For example, when the carrier 12 is made of a light-transmissive material and an alignment mark is formed by laser inner marking from the side of the second surface 12b of the carrier, the alignment mark formed inside the carrier is included in the category of the alignment mark AM provided near the second surface 12b of the carrier. In particular, the alignment mark AM formed by the above-described various printing and / or lasers is preferable because it can effectively suppress the strength reduction of the carrier 12.

[0021] The carrier 12 is preferably composed of glass, silicon, ceramics, resin, metal, or a combination thereof, more preferably composed of glass, silicon, or ceramics, and even more preferably composed of glass or silicon. Further, the carrier 12 is preferably composed of a material having light transmissibility (such as glass) as described above. The carrier 12 composed of silicon may be any one as long as it contains Si as an element, and a SiO2 substrate, a SiN substrate, a Si single crystal substrate, a Si polycrystalline substrate, etc. can be applied. According to a preferred embodiment of the present invention, the carrier 12 is in a disc shape with a diameter of 100 mm or more, more preferably in a disc shape with a diameter of 200 mm or more and 450 mm or less. Note that the carrier 12 (for example, a Si single crystal substrate) may have a notch N or an orifla (also referred to as an orientation flat) as shown in FIG. 2A in order to indicate a reference point of the crystal orientation. Generally, when the diameter of the carrier 12 is 200 mm or less, an orifla is formed, and when it is 200 mm or more, a notch is formed. According to another preferred embodiment of the present invention, the carrier 12 is in a rectangular shape with a short side of 100 mm or more, more preferably with a short side of 150 mm or more and 650 mm or less. The rectangular carrier 12 may be in a roll shape in which the long side is sufficiently long compared to the short side, but preferably the long side is 200 mm or more and 650 mm or less.

[0022] The form of the carrier 12 may be any of a sheet, a film, and a plate. Also, the carrier 12 may be a laminate of these sheets, films, plates, etc. For example, the carrier 12 may function as a rigid support such as a glass plate, a ceramic plate, a silicon wafer, a metal plate, etc., or may be in a form without rigidity such as a metal foil or a resin film. Preferred examples of the metal constituting the carrier 12 include copper, titanium, nickel, stainless steel, aluminum, etc. Preferred examples of the ceramics include alumina, zirconia, silicon nitride, aluminum nitride, and other various fine ceramics. Preferred examples of the resin include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyamide, polyimide, nylon, liquid crystal polymer, polyether ether ketone (PEEK (registered trademark)), polyamideimide, polyethersulfone, polyphenylene sulfide, polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE), etc. More preferably, from the viewpoint of preventing warping of the coreless support due to heating when mounting a semiconductor element, it is a material having a coefficient of thermal expansion (CTE) of less than 25 ppm / K (typically 1.0 ppm / K or more and 23 ppm / K or less), and examples of such materials include various resins as described above (particularly low thermal expansion resins such as polyimide and liquid crystal polymer), glass, silicon, and ceramics. Also, from the viewpoints of handleability and ensuring flatness during chip mounting, the carrier 12 preferably has a Vickers hardness of 100 HV or more, more preferably 150 HV or more and 2500 HV or less. As a material satisfying these characteristics, the carrier 12 is preferably composed of glass, silicon, or ceramics, more preferably composed of glass or ceramics, and particularly preferably composed of glass.

[0023] Examples of the carrier 12 made of glass include a glass plate. When glass is used as the carrier 12, there are advantages such as being lightweight, having a low coefficient of thermal expansion, high insulation, being rigid, and having a flat surface, so that the surface of the metal layer 18 can be made extremely smooth. Further, when the carrier 12 is glass, there are advantages such as having surface flatness (coplanarity) advantageous for forming a fine circuit, and having chemical resistance in a desmear process in a wiring manufacturing process and various plating processes. Preferred examples of the glass constituting the carrier 12 include fused silica, borosilicate glass, non-alkali glass, soda-lime glass, aluminosilicate glass, and combinations thereof. More preferably, they are non-alkali glass, soda-lime glass, and combinations thereof, and particularly preferably non-alkali glass. Non-alkali glass is glass that mainly contains silicon dioxide, aluminum oxide, boron oxide, and alkaline earth metal oxides such as calcium oxide and barium oxide, and further contains boric acid, and substantially does not contain alkali metals. This non-alkali glass has the advantage that the warping of the glass in a process involving heating can be minimized because the coefficient of thermal expansion is low and stable in the range of 3 ppm / K or more and 5 ppm / K or less in a wide temperature range from 0 °C to 350 °C. The thickness of the carrier 12 is preferably 100 μm or more and 2000 μm or less, more preferably 300 μm or more and 1800 μm or less, and even more preferably 400 μm or more and 1100 μm or less. When the carrier 12 has a thickness within such a range, it is possible to realize thinning of the wiring and reduction of warping that occurs when mounting an electronic component while ensuring appropriate strength that does not hinder handling.

[0024] The intermediate layer 14 provided as desired is a layer interposed between the carrier 12 and the release layer 16 and contributing to ensuring the adhesion between the carrier 12 and the release layer 16. Examples of the metal 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 sometimes 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, still 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 impurities due to raw material components, film formation processes, etc. Also, although not particularly limited, when the intermediate layer 14 is exposed to the atmosphere after film formation, the presence of oxygen mixed in due to this is allowed. The upper limit of the content of the above metal is not particularly limited and may be 100 atomic %. The intermediate layer 14 is preferably a layer formed by a physical vapor deposition (PVD) method, more preferably a layer formed by sputtering. The intermediate layer 14 is particularly preferably a layer formed by a magnetron sputtering method using a metal target from the viewpoint of the uniformity of the film thickness distribution. The thickness of the intermediate layer 14 is preferably 10 nm or more and 1000 nm or less, more preferably 30 nm or more and 800 nm or less, still more preferably 60 nm or more and 600 nm or less, and particularly preferably 100 nm or more and 400 nm or less. By setting the thickness in this way, it becomes possible to obtain an intermediate layer having the same roughness as the carrier. This thickness is a value measured by analyzing the layer cross-section with an energy dispersive X-ray spectrometer (TEM-EDX) of a transmission electron microscope.

[0025] The intermediate layer 14 may have a single-layer structure or a multi-layer structure of two or more layers. When the intermediate layer 14 has a single-layer structure, the intermediate layer 14 preferably consists of a layer containing a metal composed of Cu, Al, Ti, Ni, or a combination thereof (for example, an alloy or an intermetallic compound), more preferably Al, Ti, or a combination thereof (for example, an alloy or an intermetallic compound), and still 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 adopted for the intermediate layer 14, it is preferable to form the intermediate layer 14 with a two-layer structure. That is, by providing a layer made of a metal (for example, Ti) or an alloy having excellent adhesion to the carrier 12 adjacent to the carrier 12, and providing a layer made of a metal (for example, Cu) or an alloy having poor adhesion to the carrier 12 adjacent to the release layer 16, the adhesion to the carrier 12 can be improved. Therefore, as an example of a preferable two-layer structure of the intermediate layer 14, a laminated structure including a Ti-containing layer adjacent to the carrier 12 and a Cu-containing layer adjacent to the release layer 16 can be mentioned. In addition, since the peeling strength also changes when the balance of the constituent elements and thicknesses of each layer in the two-layer structure is changed, it is preferable to appropriately adjust the constituent elements and thicknesses of each layer. In this specification, the category of the "metal M-containing layer" includes alloys containing elements other than metal M as long as the peelability of the carrier is not impaired. Therefore, the intermediate layer 14 can also be said to be a layer mainly containing metal M. From the above points, the content ratio of metal M 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, still 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.

[0026] When the intermediate layer 14 is made of an alloy, examples of preferable alloys include Ni alloys. The Ni alloy preferably has a Ni content of 45 wt% or more and 98 wt% or less, more preferably 55 wt% or more and 90 wt% or less, and even more preferably 65 wt% or more and 85 wt% or less. A preferable 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, from the viewpoint of the uniformity of the film thickness distribution, a layer formed by a magnetron sputtering method using a Ni alloy target is particularly preferable.

[0027] The release layer 16 is a layer that enables or facilitates the release of the carrier 12 and, if present, the intermediate layer 14. In addition to being peelable by physically applying force, the release layer 16 may also be peelable by a laser peeling method (laser lift-off, LLO). When the release layer 16 is made of a material that can be peeled by laser lift-off, the release layer 16 may be composed of a resin whose interfacial adhesion strength decreases upon irradiation with a laser beam after curing, or may be a layer such as silicon, silicon carbide, or a metal oxide that is modified by laser beam irradiation. Further, the release layer 16 may be either an organic release layer or an inorganic release layer. Examples of the organic components used in the organic release layer include nitrogen-containing organic compounds, sulfur-containing organic compounds, carboxylic acids, etc. Examples of the nitrogen-containing organic compounds include triazole compounds, imidazole compounds, etc. On the other hand, examples of the inorganic components used in the inorganic release layer include metal oxides or metal oxynitrides containing at least one or more of Ni, Mo, Co, Cr, Fe, Ti, W, P, Zn, Cu, Al, Nb, Zr, Ta, Ag, In, Sn, Ga, or a carbon layer, etc. Among these, in particular, the release layer 16 is preferably a carbon-containing layer, i.e., a layer mainly composed of carbon, more preferably a layer mainly composed of carbon or hydrocarbon, and even more preferably a layer composed of amorphous carbon which is a hard carbon film. In this case, it is preferable that the carbon concentration measured by XPS of the release layer 16 (i.e., the carbon-containing layer) is 60 atomic% or more, more preferably 70 atomic% or more, even more preferably 80 atomic% or more, and particularly preferably 85 atomic% or more. The upper limit value of the carbon concentration is not particularly limited and may be 100 atomic%, but 98 atomic% or less is realistic. The release layer 16 may contain impurities (e.g., oxygen, hydrogen, etc. derived from the surrounding environment such as the atmosphere). Further, due to the film formation method of the metal layer 18 or the like, metal atoms of types other than the metal contained as the release layer 16 may be mixed into the release layer 16.When a carbon-containing layer is used as the release layer 16, the mutual diffusibility and reactivity with the carrier are small, and even when subjected to press working or the like at a temperature exceeding 300°C, the formation of a metal bond due to high-temperature heating between the metal layer and the bonding interface is prevented, and the state where the carrier can be easily peeled off and removed can be maintained. This release layer 16 is also preferably a layer formed by a vapor phase method such as sputtering from the viewpoints of suppressing excessive impurities in the release layer 16 and the continuous productivity with the film formation of the intermediate layer 14 provided as desired. When a carbon-containing layer is used as the release layer 16, the thickness is preferably 1 nm or more and 20 nm or less, more preferably 1 nm or more and 10 nm or less. By setting the thickness in this way, it is possible to form a release layer having the same roughness as the carrier and having a release function. This thickness is a value measured by analyzing the layer cross section with an energy dispersive X-ray spectrometer (TEM-EDX) of a transmission electron microscope.

[0028] The release layer 16 may include each layer of a metal oxide layer and a carbon-containing layer, or may be a layer containing both a metal oxide and carbon. In particular, when the carrier-attached metal foil 10 includes the 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 accompanying the heating of the metal elements derived from the intermediate layer 14 and the metal layer 18. As a result, for example, even after heating at a high temperature of 350 ° C or higher, it is possible to maintain stable releasability. 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 particularly preferably a layer formed by a reactive sputtering method in which sputtering is performed in an oxidizing atmosphere using a metal target, because 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 or more and 100 nm or less. As the upper limit value of the thickness of the metal oxide layer, more preferably it is 60 nm or less, still more preferably 30 nm or less, and particularly preferably 10 nm or less. This thickness is a value measured by analyzing the layer cross section with an energy dispersive X-ray spectrometer (TEM-EDX) of a transmission electron microscope. At this time, the order in which the metal oxide layer and the carbon layer are laminated as the release layer 16 is not particularly limited. Further, the release layer 16 may exist in a mixed phase state (that is, a layer containing both a metal oxide and carbon) in which the boundary between the metal oxide layer and the carbon-containing layer is not clearly specified.

[0029] Similarly, from the viewpoint of maintaining stable peelability even after heat treatment at high temperature, the release layer 16 may be a metal-containing layer in which the surface on the side adjacent to the metal layer 18 is a fluorinated surface and / or a nitrided surface. In the metal-containing layer, it is preferable that a region where the sum of the fluorine content and the nitrogen content is 1.0 atomic% or more (hereinafter referred to as the “(F + N) region”) exists over a thickness of 10 nm or more, and the (F + N) region is preferably present on the metal layer 18 side of the metal-containing layer. The thickness (SiO2 conversion) of the (F + N) region is a value specified by performing depth-direction elemental analysis of the carrier-attached metal foil 10 using XPS. The fluorinated surface or the nitrided surface can be preferably formed by reactive ion etching (RIE) or reactive sputtering method. On the other hand, the metal element contained in the metal-containing layer preferably has a negative standard electrode potential. Preferred examples of the metal element contained in the metal-containing layer include Cu, Ag, Sn, Zn, Ti, Al, Nb, Zr, W, Ta, Mo, and combinations thereof (for example, alloys and intermetallic compounds). The content ratio of the metal element in the metal-containing layer is preferably 50 atomic% or more and 100 atomic% or less. The metal-containing layer may be a single layer composed of one layer or a multilayer composed of two or more layers. The total thickness of the metal-containing layer is preferably 10 nm or more and 1000 nm or less, more preferably 30 nm or more and 500 nm or less, still more preferably 50 nm or more and 400 nm or less, and particularly preferably 100 nm or more and 300 nm or less. The thickness of the metal-containing layer itself is a value measured by analyzing the layer cross-section with an energy dispersive X-ray spectrometer (TEM-EDX) of a transmission electron microscope.

[0030] 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 on the side 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. Also, from the viewpoint of ensuring the 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. By doing so, it is possible to suppress the number of foreign particles on the surface of the metal layer 18, improve the circuit formation property, and maintain a stable release strength even after being heated at a high temperature for a long time. The thickness of the metal oxynitride-containing layer is preferably 5 nm or more and 500 nm or less, more preferably 10 nm or more and 400 nm or less, still more preferably 20 nm or more and 200 nm or less, and particularly preferably 30 nm or more and 100 nm or less. This thickness is a value measured by analyzing the layer cross-section with an energy-dispersive X-ray spectrometer (TEM-EDX) of a transmission electron microscope.

[0031] The metal layer 18 is a layer composed of a metal. The metal layer 18 may have a single-layer structure or a structure of two or more layers. When the metal layer 18 is composed of two or more layers, the metal layer 18 can have a structure in which each metal layer from the first metal layer to the m-th metal layer (m is an integer of 2 or more) is sequentially laminated on the side opposite to the carrier 12 of the release layer 16. The total thickness of the metal layer 18 is preferably 1 nm or more and 2000 nm or less, preferably 100 nm or more and 1500 nm or less, more preferably 200 nm or more and 1000 nm or less, still more preferably 300 nm or more and 800 nm or less, and particularly preferably 350 nm or more and 500 nm or less. The thickness of the metal layer 18 is a value measured by analyzing the layer cross-section with an energy-dispersive X-ray spectrometer (TEM-EDX) of a transmission electron microscope. Hereinafter, an example in which the metal layer 18 is composed of two layers, i.e., the first metal layer and the second metal layer, will be described.

[0032] The first metal layer preferably imparts desired functions such as an etching stopper function and an antireflection function to the carrier-attached metal foil. Preferred examples of the metal constituting the first metal layer include Ti, Al, Nb, Zr, Cr, W, Ta, Co, Ag, Ni, Mo, and combinations thereof. More preferably, they are Ti, Zr, Al, Cr, W, Ni, Mo, and combinations thereof. Even more preferably, they are Ti, Al, Cr, Ni, Mo, and combinations thereof. Particularly preferably, they are Ti, Mo, and combinations thereof. These elements have the property of being hardly soluble in a flash etching solution (for example, a copper flash etching solution). As a result, they can exhibit excellent chemical resistance to the flash etching solution. Therefore, the first metal layer becomes a layer that is less likely to be etched by the flash etching solution than the second metal layer described later. Thus, it can function as an etching stopper layer capable of delaying the progress of etching. Further, since the above-described metals constituting the first metal layer also have a function of preventing light reflection, the first metal layer can also function as an antireflection layer for improving visibility in image inspection (for example, automatic optical inspection (AOI)). The first metal layer may be a pure metal or an alloy. The metal constituting the first metal layer may contain impurities caused by raw material components, film formation processes, etc. Also, the upper limit of the content of the above metal is not particularly limited and may be 100 atomic%. The first metal layer is preferably a layer formed by a physical vapor deposition (PVD) method, and more preferably a layer formed by sputtering. The thickness of the first metal layer is preferably 1 nm or more and 500 nm or less, more preferably 10 nm or more and 400 nm or less, even more preferably 30 nm or more and 300 nm or less, and particularly preferably 50 nm or more and 200 nm or less.

[0033] Preferred examples of the metal constituting the second metal layer include transition elements of Group 4, Group 5, Group 6, Group 9, Group 10, and Group 11, Al, and combinations thereof (e.g., alloys and intermetallic compounds). More preferably, they are transition elements of Group 4 and Group 11, Al, Nb, Co, Ni, Mo, and combinations thereof. Even more preferably, they are transition elements of Group 11, Ti, Al, Mo, and combinations thereof. Particularly preferably, they are Cu, Ti, Mo, and combinations thereof. Most preferably, it is Cu. The second metal layer may be manufactured by any method. For example, it may be a metal foil formed by a wet film-forming method such as electroless metal plating and electrolytic metal plating, a physical vapor deposition (PVD) method such as sputtering and vacuum evaporation, chemical vapor deposition, or a combination thereof. A particularly preferred second metal layer is a metal layer formed by a physical vapor deposition (PVD) method such as sputtering or vacuum evaporation from the viewpoint of being easily adaptable to fine pitch formation by thinning. Most preferably, it is a metal layer manufactured by the sputtering method. Also, the second metal layer is preferably a metal layer that has not been roughened, but may be one that has been secondarily roughened by a preliminary roughening treatment, a soft etching treatment, a cleaning treatment, or an oxidation-reduction treatment as long as it does not hinder the formation of the wiring pattern. From the viewpoint of adapting to fine pitch formation, the thickness of the second metal layer is preferably 10 nm or more and 1000 nm or less, more preferably 20 nm or more and 900 nm or less, even more preferably 30 nm or more and 700 nm or less, even more preferably 50 nm or more and 600 nm or less, particularly preferably 70 nm or more and 500 nm or less, and most preferably 100 nm or more and 400 nm or less. A metal layer having a thickness within such a range is preferably manufactured by the sputtering method from the viewpoints of in-plane uniformity of the film thickness and productivity in the form of a sheet or a roll.

[0034] When the metal layer 18 is composed of a single layer, it is preferable to directly adopt the above-described second metal layer as the metal layer 18. On the other hand, when the metal layer 18 is composed of n layers (n is an integer of 3 or more), it is preferable that the first to (n - 1)th metal layers of the metal layer 18 have the configuration of the above-described first metal layer, and it is preferable that the outermost layer of the metal layer 18, that is, the nth metal layer, has the configuration of the above-described second metal layer.

[0035] The intermediate layer 14 (if present), the release layer 16, and the metal layer 18 are each preferably a physical vapor deposition (PVD) film, that is, a film formed by a physical vapor deposition (PVD) method, and more preferably a sputtered film, that is, a film formed by a sputtering method.

[0036] It is preferable that the metal layer 18, optionally the intermediate layer 14, and optionally the release layer 16 (that is, at least the metal layer 18, for example, the metal layer 18 and the intermediate layer 14) extend to the end face of the carrier 12 so that the end face is covered. That is, it is preferable that not only the surface of the carrier 12 but also the end face is covered with at least the metal layer 18. By covering the end face as well, it is possible to prevent the intrusion of chemical solutions into the carrier 12 in the manufacturing process of the wiring board, and it is possible to strongly prevent chipping due to peeling at the side end when handling the metal foil with carrier 10, that is, chipping of the film (that is, the metal layer 18) on the release layer 16. The covered area at the end face of the carrier 12 is preferably an area of 0.1 mm or more, more preferably an area of 0.2 mm or more, and still more preferably over the entire end face area of the carrier 12, in the thickness direction (that is, the direction perpendicular to the carrier surface) from the surface of the carrier 12.

[0037] The thickness of the entire metal foil with carrier 10 is not particularly limited, but is preferably 500 μm or more and 3000 μm or less, more preferably 700 μm or more and 2500 μm or less, still more preferably 900 μm or more and 2000 μm or less, and particularly preferably 1000 μm or more and 1700 μm or less. The size of the metal foil with carrier 10 is not particularly limited, but is preferably a diameter of 10 cm or more or a 10 cm square or more, more preferably a diameter of 20 cm or more or a 20 cm square or more, still more preferably a diameter of 25 cm or more or a 25 cm square or more. The upper limit of the size of the metal foil with carrier 10 is not particularly limited, but a diameter of 1000 cm or a 1000 cm square can be cited as one standard of the upper limit. Also, the metal foil with carrier 10 is in a form that can be handled alone before and after the formation of the resin-containing layer 22.

[0038] Laminated body According to a preferred embodiment of the present invention, a laminate including a metal foil with a carrier 10 is provided. An example of the laminate of the present invention is shown in FIG. 4. As shown in FIG. 4, the laminate 20 includes a metal foil with a carrier 10 and a resin-containing layer 22 provided on the metal layer 18 of the metal foil with a carrier 10. The resin-containing layer 22 preferably includes a wiring layer 22a, an insulating layer 22b, and / or a molded resin layer 22c. More preferably, as shown in FIG. 4, the resin-containing layer 22 includes an insulating layer 22b and a wiring layer 22a formed inside and / or on the surface of the insulating layer 22b, and further includes a molded resin layer 22c that covers or embeds the wiring layer 22a, the insulating layer 22b, and the metal foil with a carrier 10. The resin-containing layer 22 (for example, the insulating layer 22b and / or the molded resin layer 22c) preferably contains an insulating resin. Examples of such insulating resins include epoxy resins and phenolic resins.

[0039] The laminate 20 can be preferably manufactured by the processes shown in FIGS. 5 and 6, for example. First, the above-described metal foil with a carrier 10 is prepared (FIG. 5(i)), and the wiring layer 22a and the insulating layer 22b are formed on the surface of the metal layer 18 (FIG. 5(ii)). The formation of the wiring layer 22a and the insulating layer 22b may be performed by known methods, and for example, the above-described coreless build-up method can be preferably adopted. Further, if necessary, formation of pillars (columnar electrodes) P, mounting of chips C, etc. may be performed on the wiring layer 22a and / or the insulating layer 22b (FIG. 5(iii)). Then, at least a part of the side surface of the metal foil with a carrier 10 (preferably the whole except the second surface 12b of the metal foil with a carrier 10), and the wiring layer 22a and the insulating layer 22b are molded so that they are covered or embedded by the molded resin layer 22c to obtain the laminate 20 (FIG. 6(iv)). If desired, the upper surface of the molded resin layer 22c may be ground and / or chemically mechanically polished (CMP) to expose the pillars P, etc. from the molded resin layer 22c (FIG. 6(v)). Also, the size of the laminate 20 may be adjusted by cutting the side surface of the molded resin layer 22c.

[0040] The resin-containing layer 22 (for example, the molded resin layer 22c) preferably covers at least a part of the side surface of the metal foil 10 with a carrier, and thereby has an extension portion E extending outside the end surface of the carrier 12. More preferably, as shown in FIG. 4, the resin-containing layer 22 (for example, the molded resin layer 22c) embeds the entire part other than the second surface 12b of the metal foil 10 with a carrier. The laminate 20 of this aspect can be said to be the result of performing full molding on the metal foil 10 with a carrier. Here, an example of manufacturing a laminate having a full mold structure and a laminate having a flange mold structure using a mold is shown in FIGS. 7 and 8, respectively. In this regard, the laminate 20 having a full mold structure as shown in FIG. 7(ii) has an advantage that breakage of the carrier or the like is suppressed and the yield is improved as compared with the laminate 20 having a flange mold structure shown in FIG. 8(ii). That is, as shown in FIG. 8(i), in the mold M for performing flange molding, there is a space for forming a molded resin layer only on one surface side of the metal foil 10 with a carrier. For this reason, resin residues accumulate in the space, and a local force caused by the resin residues is likely to be applied to the surface of the metal foil 10 with a carrier during compression molding. As a result, breakage of the carrier or the like is likely to occur. On the other hand, as shown in FIG. 7(i), in the mold M for performing full molding, since there is a space not only on the upper surface but also on the side surface of the metal foil 10 with a carrier, a local force caused by the resin residues is less likely to be applied to the surface of the metal foil 10 with a carrier. As a result, it is considered that breakage of the carrier or the like is less likely to occur.

[0041] On one hand, in the laminate 20 with a full mold structure, the resin-containing layer 22 covers at least a part of the side surface of the metal foil with carrier 10, and preferably the resin-containing layer 22 embeds the entire metal foil with carrier 10 other than the second surface 12b. Therefore, it becomes larger in size than the metal foil with carrier 10. For this reason, there may occur a problem that the process cannot proceed to the formation process of the rewiring layer on the resin-containing layer 22, which is a process after the mold forming, because the size of the laminate 20 deviates from the specifications of the device. In this regard, according to the laminate 20, since the deviation from the center position and the angular deviation of the carrier can be accurately detected based on the alignment mark AM provided on the second surface 12b of the carrier, by appropriately installing the laminate 20 on the cutting device based on this, it becomes possible to appropriately perform the downsizing of the laminate 20. The length of the extension portion E away from the end surface of the carrier after downsizing is preferably 1.0 mm or less, more preferably 0.5 mm or less, still more preferably 0.3 mm or less, and particularly preferably 0.1 mm or less. If desired, it may be -0.1 mm or less, that is, all of the extension portion E may be cut off, and further the carrier 12 may also be cut.

[0042] Method for manufacturing wiring board According to another preferred embodiment of the present invention, a method for manufacturing a wiring board using the metal foil with carrier 10 is provided. This method includes the steps of (1) preparing the metal foil with carrier, (2) forming the resin-containing layer, (3) cutting the extension portion of the resin-containing layer, and (4) forming the rewiring layer if desired. Hereinafter, each of the steps (1) to (4) will be described with reference to the drawings.

[0043] (1) Preparation of the metal foil with carrier Prepare a metal foil with carrier 10 provided with an intermediate layer 14 (i.e., an arbitrary layer), a release layer 16, and a metal layer 18, which are provided on one surface (i.e., the first surface 12a) of the carrier 12 if desired (Fig. 9(i)). The metal foil with carrier 10 has at least one alignment mark AM on the second surface 12b of the carrier. In addition, the preferred embodiments of the metal foil with carrier 10 are as described above.

[0044] The formation of the alignment mark AM is preferably performed on the second surface 12b of the carrier by laser printing, laser engraving, gravure printing, flexographic printing, inkjet printing, silk printing, laser inner marking, drilling, or a combination thereof. More preferably, it is laser inner marking, laser engraving, or a combination thereof, and even more preferably, laser inner marking.

[0045] The formation of each of the intermediate layer 14 (if present), the release layer 16, and the metal layer 18 is preferably performed by a physical vapor deposition (PVD) method from the viewpoint of being easily adaptable to fine pitch formation by thinning. Examples of the physical vapor deposition (PVD) method include sputtering, vacuum evaporation, and ion plating. However, from the viewpoints of film thickness control in a wide range such as 0.05 nm or more and 5000 nm or less, and ensuring film thickness uniformity over a wide width or area, the most preferable is the sputtering method. In particular, by forming all of the intermediate layer 14 (if present), the release layer 16, and the metal layer 18 by the sputtering method, the manufacturing efficiency is significantly improved.

[0046] The film formation by the physical vapor deposition (PVD) method may be performed under known conditions using a known vapor phase film formation apparatus, and is not particularly limited. For example, when the sputtering method is adopted, the sputtering method may be various known methods such as magnetron sputtering, bipolar sputtering, and facing target sputtering, but magnetron sputtering is preferred in terms of high film formation speed and high productivity. Sputtering may be performed with either a DC (direct current) or RF (radio frequency) power source. In addition, a plate-type target, which is widely known, may be used as the target shape, but a cylindrical target is preferably used from the viewpoint of target utilization efficiency. 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 the argon gas may be appropriately determined according to the sputtering chamber size and film formation conditions, and is not particularly limited. In addition, from the viewpoint of continuous film formation without operational failure such as abnormal discharge and plasma irradiation failure, the pressure during film formation is preferably in the range of 0.1 Pa to 20 Pa. This pressure range may be set by adjusting the deposition power and the flow rate of argon gas according to the structure and capacity of the device, the exhaust capacity of the vacuum pump, the rated capacity of the deposition power source, etc. Also, the sputtering power is set to 0.05 W / cm per unit area of ​​the target, taking into consideration the uniformity of the deposited film thickness, productivity, etc. 2 More than 10.0W / cm 2 It may be set appropriately within the following range.

[0047] (2) Formation of a resin-containing layer A resin-containing layer 22 is formed on the metal layer 18 of the metal foil with a carrier 10 to obtain a laminate 20 (FIG. 9(ii)). The resin-containing layer 22 is formed so as to cover at least a part of the side surface of the metal foil with a carrier 10, thereby forming an extension E extending outward beyond the end surface of the carrier 12. Preferably, the resin-containing layer 22 is formed so as to embed the entire metal foil with a carrier 10 except for the second surface 12b.

[0048] As described above with respect to the laminate 20 with reference to FIGS. 5 and 6, the resin-containing layer 22 preferably includes a wiring layer 22a and an insulating layer 22b, and more preferably further includes a mold resin layer 22c that covers or embeds the wiring layer 22a, the insulating layer 22b, and the carrier-attached metal foil 10. For example, the wiring layer 22a and the insulating layer 22b may be formed on the surface of the metal layer 18 by a coreless build-up method (FIG. 5(ii)). Specifically, a photoresist is laminated on the metal layer 18, and exposure and development are performed to form a resist pattern so as to have a predetermined pattern. Prior to this exposure, alignment may be performed using the alignment mark AM provided on the second surface 12b of the carrier. Then, electroplating (for example, electrocopper plating) is applied between the resist patterns, and after the resist pattern is peeled off, unnecessary portions of the metal layer 18 (that is, portions where wiring patterns are not formed) exposed by the peeling of the resist pattern are removed by etching to form the first wiring layer. Thereafter, an insulating layer and the nth wiring layer (n is an integer of 2 or more) are alternately formed on the surface of the carrier-attached metal foil 10 on which the first wiring layer is formed. In this way, a layer including an insulating layer and a wiring layer formed inside and / or on the surface of the insulating layer (that is, a rewiring layer) is obtained. If desired, formation of the pillar P and mounting of the chip C can be performed on the wiring layer 22a and / or the insulating layer 22b (FIG. 5(iii)). Thereafter, at least a part of the side surface of the carrier-attached metal foil 10 (preferably the whole except for the second surface 12b of the carrier-attached metal foil 10), and the wiring layer 22a and the insulating layer 22b are covered or embedded to mold the mold resin layer 22c, and the laminate 20 can be preferably obtained (FIG. 6(iv)).

[0049] Before forming the rewiring layer described later, it is preferably further included a step of polishing the surface of the resin-containing layer 22 (for example, the mold resin layer 22c). Preferred examples of surface polishing include grinding using a grindstone and chemical mechanical polishing (CMP). For example, by polishing the upper surface of the mold resin layer 22c, as shown in FIG. 6(v), the pillar P or the like may be exposed from the mold resin layer 22c. The polishing of the resin-containing layer 22 may be performed before the excision of the extending portion E described later, or may be performed after the excision of the extending portion E.

[0050] (3) Resin-containing layer extension removal Positioning is performed based on the alignment mark AM provided on the second surface 12b of the carrier, and at least a part of the extension E is removed (Fig. 9(iii)). By doing so, the laminate 20 can be downsized to a size corresponding to the specifications of the apparatus for forming the rewiring layer described later.

[0051] As described above, since the alignment mark AM is provided on the surface of the metal foil with carrier 10 opposite to the metal layer 18 of the carrier 12 (i.e., the second surface 12b), even after the entire metal foil with carrier 10 other than the second surface 12b is embedded with the resin-containing layer 22, the alignment mark AM can be identified from the second surface 12b side. Therefore, alignment of the laminate 20 after formation of the resin-containing layer 22 can be accurately performed based on the alignment mark AM. As a result, even when misalignment occurs during mold forming, it is possible to remove the extension E with the desired width.

[0052] The removal of the extension E is preferably performed such that when the metal foil with carrier 10 after formation of the resin-containing layer 22 is viewed in plan view, the extension width of the portion extending from the end face of the carrier 12 in the resin-containing layer 22 is 1.0 mm or less, more preferably 0.5 mm or less, still more preferably 0.3 mm or less, particularly preferably 0.2 mm or less, and most preferably 0.1 mm or less. The method for removing the extension E is not particularly limited, and for example, it can be performed using a cutting tool such as a cutter or a machine tool such as a cutting blade. Alternatively, the extension E can be preferably removed by using a cutting device described later.

[0053] (4) Formation of rewiring layer (optional process) If desired, a rewiring layer 24 is formed on the surface of the resin-containing layer 22 (FIG. 9(iv)). In the present invention, the rewiring layer means a layer including an insulating layer and a wiring layer formed inside and / or on the surface of the insulating layer. For example, the rewiring layer 24 can be obtained by forming the wiring layer 24a and the insulating layer 24b by the above-described coreless build-up method.

[0054] After the formation of the rewiring layer 24, a step of mounting an electronic element such as a chip on the rewiring layer 24 may be further performed, and it may be used as a wiring board. By stacking a plurality of IC packages together with the chip C that can be embedded in the above-described resin-containing layer 22 and mounting them on a substrate, the integration degree can be improved. Also, the carrier 12, the intermediate layer 14 (if present), the release layer 16, and the metal layer 18 may be removed by a known method.

[0055] Examples of the electronic element mounted on the rewiring layer 24 assumed as an optional step include a semiconductor element, a chip capacitor, a resistor, etc. Examples of the method of mounting the electronic element include a flip chip mounting method, a die bonding method, etc. The flip chip mounting method is a method of joining the mounting pads of the electronic element and the rewiring layer. Pillars, solder bumps, etc. may be formed on the mounting pads, and an NCF (Non-Conductive Film), which is a sealing resin film, etc. may be attached to the surface of the rewiring layer before mounting. The joining is preferably performed using a low melting point metal such as solder, but an anisotropic conductive film, etc. may also be used. The die bonding adhesion method is a method of adhering the surface of the rewiring layer opposite to the mounting pad surface of the electronic element. For this adhesion, it is preferable to use a paste or a film, which is a resin composition containing a thermosetting resin and a thermally conductive inorganic filler.

[0056] Cutting device According to another preferred embodiment of the present invention, a cutting device for downsizing the laminate 20 is provided. This cutting device is assumed to be used, for example, in the step of removing the extending portion E of the resin-containing layer 22 in the above-described method for manufacturing a wiring board. The cutting device has a fixing portion, an identifying portion, and a cutting portion. The fixing portion supports and fixes the laminate 20. The fixing means for the laminate 20 by the fixing portion is not particularly limited and may be any means. For example, the fixing portion may have a stage on which the laminate 20 can be placed and a suction means (for example, a vacuum pump) capable of sucking the laminate 20 toward the stage through suction holes provided in the stage. Further, the stage may be a known alignment stage capable of moving the laminate 20 in the horizontal direction and the rotational direction, and thereby moving the laminate 20 with a detected misalignment to a correct position. The fixing portion may support and fix the second surface 12b side of the carrier in the laminate 20, or may support and fix the side opposite to the second surface 12b of the carrier. Alternatively, the fixing portion may fix the side surface portion of the laminate 20. When the fixing portion fixes the second surface 12b side of the carrier, it is preferable that, for example, the stage is made of a light-transmissive material so that the identifying portion can recognize the alignment mark AM. The identifying portion recognizes the alignment mark AM from the second surface 12b side of the carrier with respect to the laminate 20 fixed by the fixing portion, and specifies the position information of the laminate 20. The identifying portion can be a known positioning means such as an image processing system. For example, the identifying portion may have an imaging means (for example, a CCD camera) capable of imaging the second surface 12b side of the carrier and a pattern matching means for recognizing the alignment mark AM from the captured image data. The cutting portion cuts the side surface (for example, the extending portion E of the resin-containing layer 22) of the laminate 20 whose position information has been specified by the identifying portion. The cutting portion may have a cutting means such as a rotary blade and a movable means for moving the cutting means in the vertical direction and / or the horizontal direction. For example, based on the position information of the laminate 20, the cutting portion can cut unnecessary portions while the rotary blade or the like moves along the side surface of the laminate 20 (that is, the cutting location) by the movable means.In order to perform the above operations, the cutting device preferably further has control means for controlling the fixing part, the identification part and / or the resection part.

Claims

1. A metal foil with carrier, comprising a carrier having a first surface and a second surface, a release layer provided on the first surface, and a metal layer provided on the release layer, wherein the metal foil with carrier has at least one alignment mark on the second surface of the carrier or in the vicinity thereof.

2. The metal foil with carrier according to claim 1, wherein at least one of the alignment marks is located on the geometric center of the second surface of the carrier.

3. The metal foil with carrier according to claim 1 or 2, wherein the alignment mark has at least one shape selected from the group consisting of a cross shape, a polygon, a star polygon, a circular shape, an elliptical shape, a character, and a symbol.

4. The metal foil with carrier according to claim 1 or 2, wherein the carrier is composed of at least one selected from the group consisting of glass, silicon, ceramics, resin, and metal.

5. The metal foil with carrier according to claim 1 or 2, wherein the alignment mark is formed by at least one selected from the group consisting of laser printing, laser engraving, gravure printing, flexographic printing, inkjet printing, silk printing, laser inner marking, and drilling.

6. A laminate, comprising the metal foil with carrier according to claim 1 or 2, and a resin-containing layer provided on the metal layer.

7. The laminate according to claim 6, wherein the resin-containing layer covers at least a part of the side surface of the metal foil with carrier, thereby having an extension portion extending outside the end surface of the carrier.

8. The laminate according to claim 7, wherein the resin-containing layer embeds the entire part of the metal foil with carrier other than the second surface.

9. The laminate according to claim 6, wherein the resin-containing layer contains an insulating resin.

10. A method for manufacturing a wiring board, comprising: a step of preparing the metal foil with carrier according to claim 1 or 2; a step of forming a resin-containing layer on the metal layer of the metal foil with carrier, wherein the resin-containing layer is formed so as to cover at least a part of the side surface of the metal foil with carrier, thereby having an extension portion extending outside the end surface of the carrier; a step of performing positioning based on the alignment mark provided on the second surface of the carrier, and cutting at least a part of the extension portion; The method for manufacturing a wiring board includes the above steps.

11. The method for manufacturing a wiring board according to claim 10, wherein when the metal foil with a carrier formed with the resin-containing layer is viewed in a plan view, the extending portion of the resin-containing layer extending from the end face of the carrier is cut so that the extending width is 1.0 mm or less.

12. The method for manufacturing a wiring board according to claim 10, further comprising a step of forming a rewiring layer on the surface of the resin-containing layer after cutting at least a part of the extending portion.

13. The method for manufacturing a wiring board according to claim 12, further comprising a step of polishing the surface of the resin-containing layer before forming the rewiring layer.

14. The method for manufacturing a wiring board according to claim 10, wherein the resin-containing layer includes a wiring layer and an insulating layer.

15. A cutting device for downsizing the laminate according to claim 7, comprising: a fixing portion for fixing the laminate; an identifying portion for recognizing the alignment mark from the second surface side of the carrier with respect to the laminate fixed by the fixing portion and specifying the position information of the laminate; a cutting portion for cutting the side surface of the laminate whose position information has been specified by the identifying portion; The cutting device having the above components.

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