Substrate production method

Abstract

The present invention provides a substrate production method that makes it possible to easily separate a carrier and a device layer. This substrate production method comprises: a step for preparing a laminate which is provided with, on a carrier and in the following order, a separation layer and a device layer; a step for fixing the laminate to a separation device which is provided with a first diaphragm that has a placement surface for placing the laminate and a first pressure application means that is able to apply pressure to the first diaphragm on a surface on the reverse side from the placement surface of the first diaphragm, said fixing of the laminate to the separation device being performed in such a manner that the carrier and the placement surface of the first diaphragm are in contact; a step for using the first pressure application means to apply pressure to the first diaphragm from the surface on the reverse side from the placement surface of the first diaphragm and expand the first diaphragm, thereby changing the shape of the carrier or the laminate; and a step for utilizing the change in shape of the carrier to generate shear stress between the carrier and the device layer, thereby separating the device layer from the laminate at the position of the separation layer.

Description

Substrate manufacturing method

[0001] This disclosure relates to a method for manufacturing a substrate.

[0002] In recent years, multilayering of printed circuit boards (PCBs) has become widespread in order to increase the mounting density and miniaturize the boards. Such multilayer PCBs are used in many portable electronic devices to reduce weight and size. However, these multilayer PCBs require further reductions in the thickness of the interlayer insulation layer and even greater weight reduction as a circuit board.

[0003] To meet these requirements, a method for manufacturing multilayer printed circuit boards using the coreless build-up method has been adopted. The coreless build-up method is a method of creating a multilayer by alternately stacking (building up) insulating layers and wiring layers without using a so-called core substrate. In the coreless build-up method, it has been proposed to use a carrier-attached metal foil to facilitate the peeling of the support from the multilayer printed circuit board. For example, Patent Document 1 (Japanese Patent Application Publication No. 2005-101137) discloses a method for manufacturing a semiconductor device mounting package substrate, which includes attaching an insulating resin layer to the carrier surface of a carrier-attached copper foil to form a support, forming a first wiring conductor on the ultrathin copper layer side of the carrier-attached copper foil by processes such as photoresist processing, pattern electrolytic copper plating, and resist removal, forming a build-up wiring layer, peeling off the carrier-attached support substrate, and removing the ultrathin copper layer.

[0004] Furthermore, in order to miniaturize embedded circuits as shown in Patent Document 1, a carrier-mounted metal foil with a metal layer thickness of 1 μm or less is desired. Therefore, in order to reduce the thickness of the metal layer, it has been proposed to form the metal layer by a vapor phase method such as sputtering. For example, Patent Document 2 (International Publication No. 2017 / 150283) discloses a carrier-mounted copper foil in which a release layer, an anti-reflective layer, and an ultrathin copper layer (e.g., a film thickness of 300 nm) are formed by sputtering on a carrier such as a glass sheet. Patent Document 3 (International Publication No. 2017 / 150284) also discloses a carrier-mounted copper foil in which an intermediate layer (e.g., an adhesive metal layer and a release assist layer), a release layer, and an ultrathin copper layer (e.g., a film thickness of 300 nm) are formed by sputtering on a carrier such as a glass sheet. Patent documents 2 and 3 also teach that interposing an intermediate layer made of a predetermined metal provides excellent stability in the mechanical peel strength of the carrier, and that the anti-reflective layer exhibits a desirable dark color, thereby improving visibility in image inspection (e.g., automated image inspection (AOI)).

[0005] In particular, with the increasing miniaturization and power saving of electronic devices, there is a growing need for higher integration and thinner semiconductor chips and printed circuit boards. To meet these needs, the adoption of FO-WLP (Fan-Out Wafer Level Packaging) and PLP (Panel Level Packaging) has been considered in recent years as next-generation packaging technologies. Furthermore, the adoption of coreless build-up methods is also being considered for FO-WLP and PLP. One such method is called the RDL-First (Reduction 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, the chip is mounted and sealed, and then the support is peeled off. For example, Patent Document 4 (Japanese Patent Application Publication No. 2015-35551) discloses a method for manufacturing a semiconductor device, which includes forming a metal delamination layer on the main surface of a support made of glass or a silicon wafer, forming an insulating resin layer thereon, forming a redisting layer (Redistrib Layer) including a build-up layer thereon, mounting and sealing a semiconductor integrated circuit thereon, exposing the delamination layer by removing the support, exposing secondary mounting pads by removing the delamination layer, forming solder bumps on the surface of the secondary mounting pads, and secondary mounting.

[0006] Incidentally, when peeling a carrier with a wiring layer fabricated using a coreless build-up method or the like, the device layer including the wiring layer may bend significantly, causing disconnection or peeling, which can reduce the reliability of the wiring layer connection. Therefore, methods for removing carriers that address this problem have been proposed. For example, Patent Document 5 (International Publication No. 2018 / 173807) discloses a method for manufacturing a wiring board, in which a composite laminate (including a support, a release layer, and a multilayer wiring board) is brought into close contact with a stage, and the support or multilayer wiring board is peeled from the release layer to form a predetermined convex curved surface. According to this method, cracks in the support and defects such as cracks and disconnections in the multilayer wiring board can be prevented, and stable peeling is possible.

[0007] Japanese Patent Publication No. 2005-101137, International Publication No. 2017 / 150283, International Publication No. 2017 / 150284, Japanese Patent Publication No. 2015-35551, International Publication No. 2018 / 173807

[0008] Although methods for separating the device layer from the carrier have been proposed, there is a need for a new method that can easily separate the carrier from the device layer.

[0009] The inventors have now discovered that in a laminate comprising a carrier, a release layer, and a device layer in that order, by fixing the carrier on a diaphragm and then pressurizing the diaphragm, the carrier and the device layer can be easily separated by utilizing the change in the shape of the carrier due to the expansion of the diaphragm, thereby enabling the manufacture of a substrate.

[0010] Therefore, an object of the present invention is to provide a method for manufacturing a substrate that allows for easy separation of the carrier and the device layer.

[0011] The following embodiments are provided according to this disclosure: [Embodiment 1] A method for manufacturing a substrate, comprising: a step of preparing a laminate having a release layer and a device layer in order on a carrier; a step of fixing the laminate to a release device, wherein the release device comprises a first diaphragm having a mounting surface for placing the laminate, and a first pressurizing means capable of pressurizing the first diaphragm from the surface of the first diaphragm opposite to the mounting surface, and the fixing of the laminate to the release device is performed such that the carrier and the mounting surface of the first diaphragm are in contact; a step of using the first pressurizing means to pressurize the first diaphragm from the surface of the first diaphragm opposite to the mounting surface to expand it, thereby changing the shape of the carrier or the laminate; and a step of utilizing the change in the shape of the carrier to generate shear stress between the carrier and the device layer, thereby peeling the device layer from the laminate at the position of the release layer. [Aspect 2] The method for manufacturing a substrate according to aspect 1, wherein the maximum difference between the pressure applied to the surface of the first diaphragm opposite to the mounting surface and the pressure applied to the mounting surface is 0.00010 MPa or more and 5.0 MPa or less.[Aspect 3] The peeling device further comprises a second diaphragm having a support surface facing the mounting surface of the first diaphragm, and a second pressurizing means capable of pressurizing the second diaphragm from the surface of the second diaphragm opposite to the support surface, and the step of fixing the laminate to the peeling device includes (i) sandwiching the laminate between the first diaphragm and the second diaphragm such that the carrier and the mounting surface of the first diaphragm are in contact, and the device layer and the support surface of the second diaphragm are in contact, and (ii) pressing the first diaphragm from the surface of the first diaphragm opposite to the mounting surface using the first pressurizing means, and pressing the second diaphragm from the surface of the second diaphragm opposite to the support surface using the second pressurizing means, thereby sandwiching the laminate between the first diaphragm and the second diaphragm. A method for manufacturing a substrate according to embodiment 1 or 2, wherein the step of changing the shape of the laminate includes increasing the pressure applied to the first diaphragm relative to the pressure applied to the second diaphragm, or decreasing the pressure applied to the second diaphragm relative to the pressure applied to the first diaphragm, thereby causing the first diaphragm to expand and changing the shape of the laminate.[Aspect 4] The laminate further comprises a second release layer provided on the side of the carrier opposite to the release layer, and a second device layer provided on the side of the second release layer opposite to the carrier, wherein the step of changing the shape of the laminate includes (i) increasing the pressurizing pressure on the first diaphragm relative to the pressurizing pressure on the second diaphragm, or decreasing the pressurizing pressure on the second diaphragm relative to the pressurizing pressure on the first diaphragm, thereby expanding the first diaphragm and changing the shape of the laminate, and (ii) increasing the pressurizing pressure on the second diaphragm relative to the pressurizing pressure on the first diaphragm, or decreasing the pressurizing pressure on the first diaphragm relative to the pressurizing pressure on the second diaphragm, thereby expanding the second diaphragm and changing the shape of the laminate, A method for manufacturing a substrate according to Embodiment 3, further comprising the step of peeling off the device layer, wherein the step of utilizing the change in shape of the laminate to generate shear stress between the carrier and the second device layer, thereby peeling off the second device layer from the laminate at the position of the second peeling layer. [Embodiment 5] A method for manufacturing a substrate according to any one of Embodiments 1 to 4, further comprising the step of laminating a reinforcing sheet on the device layer before changing the shape of the carrier. [Embodiment 6] A method for manufacturing a substrate according to Embodiment 5, wherein when changing the shape of the carrier, the device layer is peeled off from the laminate by changing the shape of the portion of the laminate other than the device layer, without bending the reinforcing sheet and the device layer supported by it. [Embodiment 7] A method for manufacturing a substrate according to any one of Embodiments 1 to 6, further comprising the step of performing a trimming process on the device layer before fixing the laminate to the peeling device, wherein the trimming process is performed by making cuts that pass inside the contour of the device layer when the laminate is viewed from above, and that penetrate the device layer when the laminate is viewed in cross-section. [Aspect 8] A method for manufacturing a substrate according to any one of aspects 1 to 7, wherein the laminate further comprises a metal layer provided between the release layer and the device layer.[Aspect 9] A method for manufacturing a substrate according to any one of aspects 1 to 8, wherein the carrier is composed of glass, silicon, metal, or ceramics. [Aspect 10] A method for manufacturing a substrate according to any one of aspects 1 to 9, wherein the carrier has a thickness of 3,000 μm or less. [Aspect 11] A method for manufacturing a substrate according to any one of aspects 1 to 10, wherein the device layer includes a wiring layer, an electronic element provided on the wiring layer, and a molded resin layer that embeds the electronic element. [Aspect 12] When the thickness direction of the laminate is the projection direction, the projected area of ​​the laminate is 1,000 mm². ２ The above is 1,000,000 mm ２ A method for manufacturing a substrate according to any one of the following embodiments 1 to 11.

[0012] This is a schematic cross-sectional flowchart showing an example of a substrate manufacturing method of the present invention, corresponding to the initial steps ((i) to (iii)). This is a schematic cross-sectional flowchart showing an example of a substrate manufacturing method of the present invention, corresponding to the later steps ((iv) to (vi)) following the steps shown in Figure 1. This is a schematic cross-sectional flowchart showing an example of a device layer formation method, corresponding to the initial steps ((i) to (iii)). This is a schematic cross-sectional flowchart showing an example of a device layer formation method, corresponding to the later steps ((iv) to (vi)) following the steps shown in Figure 3. This is a schematic cross-sectional flowchart showing another example of a substrate manufacturing method of the present invention, illustrating an embodiment in which bending of the device layer is suppressed using a reinforcing sheet. This is a schematic diagram for explaining the mechanism by which the carrier and the device layer separate. This is a schematic cross-sectional flowchart showing another example of a substrate manufacturing method of the present invention, corresponding to the initial steps ((i) and (ii)). This is a schematic cross-sectional flow diagram showing another example of the substrate manufacturing method of the present invention, corresponding to the later steps ((iii) and (iv)) following the steps shown in Figure 7. This is a schematic cross-sectional flow diagram showing another example of the substrate manufacturing method of the present invention, illustrating the peeling procedure for double-sided substrates.

[0013] Method for manufacturing a substrate The present invention relates to a method for manufacturing a substrate. The method of the present invention may include the steps of: (1) preparing a laminate, (2) trimming the device layer if desired, (3) laminating a reinforcing sheet if desired, (4) fixing the laminate to a peeling device, (5) applying pressure to a diaphragm, and (6) separating the carrier and the device layer. Hereinafter, each of steps (1) to (6) will be described with reference to the drawings. In the present specification, the substrate means a substrate including at least one of wiring, an electronic device, a material for forming an electronic device, and a substrate manufactured by electroforming (for example, a metal pattern).

[0014] (1) Preparation of a laminate Examples of the method for manufacturing a substrate of the present invention are shown in FIGS. 1 and 2. First, as shown in FIG. 1(i), a laminate 10 having a peeling layer 16 and a device layer 20 provided in this order on a carrier 12 is prepared. The peeling layer 16 is provided on the carrier 12 and contributes to the peeling between the carrier 12 and the device layer 20. The device layer 20 is a layer having a device function provided on the peeling layer 16. As shown in FIG. 4(vi), the laminate 10 preferably further includes a metal layer 18 between the peeling layer 16 and the device layer 20. The laminate 10 may further have an intermediate layer 14 between the carrier 12 and the peeling layer 16.

[0015] When the thickness direction of the laminate 10 is taken as the projection direction, the projected area of the laminate 10 is 1,000 mm ２ or more and 1,000,000 mm ２ or less, more preferably 3,000 mm ２ or more and 800,000 mm ２ or less, still more preferably 10,000 mm ２ or more and 700,000 mm ２ or less, particularly preferably 20,000 mm ２ or more and 600,000 mm ２ or less, most preferably 30,000 mm ２ or more and 400,000 mm ２ or less. Even when the size of the laminate 10 is large in this way, according to the present invention, the separation of the carrier 12 and the device layer 20 can be easily performed as described later.

[0016] The material of the carrier 12 is not particularly limited, but it is preferably made of glass, silicon, metal, ceramics, or a combination thereof. Furthermore, the carrier 12 is preferably 3000 μm or less in thickness, more preferably 2000 μm or less, and even more preferably 1600 μm or less in thickness. This makes it easier to control the shape change of the carrier 12 within a desired range in the process described later. From the viewpoint of making it easy to change the shape of the carrier 12, a thinner carrier is preferable, and although the lower limit is not particularly limited, it is typically 50 μm or more when made of metal, and typically 300 μm or more when made of glass, silicon, or ceramics.

[0017] The device layer 20 typically includes at least a wiring layer, and more preferably includes an electronic element and a molded resin layer. The wiring layer may be in the form of a redistribution layer formed by a method such as the coreless build-up method described above. The redistribution layer preferably includes a wiring pattern with a line / space (L / S) of 10 μm or less / 10 μm or less, and more preferably includes a wiring pattern with a line / space (L / S) of 5 μm or less / 5 μm or less. The lower limit of the line / space (L / S) in the wiring pattern is not particularly limited, but is typically 1 μm or more / 1 μm or more. The electronic element may be a semiconductor chip, an integrated circuit, a sensor, or other device with functional capabilities. The molded resin layer may have a structure that embeds only the electronic element, or it may have a structure that embeds both the electronic element and the wiring layer. However, the device layer 20 may mainly consist of a wiring layer and may not include an electronic element and / or a molded resin layer.

[0018] Figures 3 and 4 show a preferred example of a method for forming the device layer 20. First, a carrier-mounted metal foil is prepared, comprising an intermediate layer 14 (an optional layer), a release layer 16, and a metal layer 18 (an optional layer) in that order on a carrier 12 (Figure 3(i)). A wiring layer and an insulating layer are formed on the surface of the metal layer 18 of this carrier-mounted metal foil by a coreless build-up method to obtain a first rewiring layer 20a (Figure 3(ii)). Specifically, a photoresist is laminated onto the metal layer 18, and exposure and development are performed to form a predetermined pattern to form a resist pattern. Then, electroplating (e.g., electroplating of copper) is applied between the resist patterns, and after peeling off the resist pattern, the unnecessary parts of the metal layer 18 exposed by the peeling off of the resist pattern (i.e., parts where a wiring pattern is not formed) are removed by etching to form a first wiring layer. Subsequently, an insulating layer and an n wiring layer (n is an integer of 2 or more) are alternately formed on the surface of the carrier-mounted metal foil on which the first wiring layer is formed. Thus, a first redistribution layer 20a is obtained, which includes an insulating layer and a wiring layer formed inside and / or on the surface of the insulating layer.Optionally, pillars (columnar electrodes) P or electronic elements such as chips C may be formed on the first redistribution layer 20a (Figure 3(iii)).A molded resin layer 20b is formed by embedding the pillars P and chips C in insulating resin (Figure 4(iv)).Alternatively, the pillars P and other elements may be exposed from the molded resin layer 20b by surface polishing (Figure 4(v)).Preferred examples of surface polishing include grinding using a grinding wheel and chemical mechanical polishing (CMP).Then, a second redistribution layer 20c is formed on the surface of the molded resin layer 20b by the coreless build-up method described above (Figure 4(vi)).In this way, a laminate 10 comprising a device layer 20 including a wiring layer, electronic elements and a molded resin layer can be preferably manufactured.Other preferred embodiments of the laminate 10 will be described later.

[0019] (2) Trimming of the device layer (optional step) As shown in Figure 1(ii), the device layer 20 may be trimmed. Preferably, this trimming is performed by making cuts that pass inside the contour of the device layer 20 when the laminate 10 is viewed from above, and that penetrate the device layer 20 when the laminate 10 is viewed in cross-section. By making such cuts, a starting point for delamination can be formed, making it possible to separate the carrier 12 and the device layer 20 more easily and reliably in the process described later. The trimming is not particularly limited and any known method can be used. For example, cuts can be made in the device layer 20 using a cutting tool such as a cutter or a machine tool such as a cutting blade.

[0020] The above-mentioned cuts are preferably made so as to pass through a region 0.5 mm to 30.0 mm inward from the contour of the device layer 20 when the laminate 10 is viewed from above, more preferably 1.0 mm to 15.0 mm inward, and even more preferably 1.5 mm to 5.0 mm inward. This effectively suppresses damage to the device layer 20 (especially the wiring layer and electronic elements) when the carrier 12 is peeled off.

[0021] (3) Lamination of reinforcing sheets (optional step) As shown in Figure 5(i), a reinforcing sheet 22 may be laminated on the device layer 20. This effectively suppresses the bending of the device layer 20 supported by the reinforcing sheet 22. For example, for a device layer 20 where bending reduces the connection reliability of the wiring layer, etc., it is preferable to laminate the reinforcing sheet 22 in advance before deformation of the carrier 12, etc., due to the pressurization of the diaphragm described later. Accordingly, according to a preferred embodiment of the present invention, as shown in Figures 5(ii) and (iii), when the shape of the carrier 12 is changed, the reinforcing sheet 22 and the device layer 20 supported by it are not bent, and the device layer 20 is peeled off from the laminate 10 by changing the shape of the part of the laminate 10 other than the device layer 20 (particularly the carrier 12). Note that the lamination of the reinforcing sheet 22 may be performed before fixing the laminate 10 to the peeling device 24 described later, or it may be performed after fixing the laminate 10.

[0022] The reinforcing sheet 22 is not particularly limited in material as long as it can prevent or suppress the bending of the device layer 20, but is preferably made of metal. Preferred examples of metals that make up the reinforcing sheet 22 include aluminum and aluminum alloys (e.g., duralumin (e.g., A2017, A2024, and A7075 in JIS standards)), stainless steel, copper and copper alloys (e.g., bronze, phosphorus copper, copper-nickel alloy, copper-titanium alloy, etc.), titanium and titanium alloys, and nickel and nickel alloys.

[0023] The form of the reinforcing sheet 22 is not limited to a sheet, but may be a film, plate, or foil, as long as it can prevent or suppress the bending of the device layer 20, and is preferably in the form of a sheet or plate. The reinforcing sheet 22 may also be a laminate of these sheets, films, plates, foils, etc. The thickness of the reinforcing sheet 22 is preferably 10 μm or more and 1 mm or less, more preferably 50 μm or more and 800 μm or less, and even more preferably 100 μm or more and 600 μm or less, from the viewpoint of maintaining the strength of the reinforcing sheet and ease of handling.

[0024] The reinforcing sheet 22 may be laminated onto the device layer 20 via an adhesive layer (not shown). Preferably, the adhesive layer is a layer that can adhere the reinforcing sheet 22 to the device layer 20 with desired adhesion and can be removed from the device layer 20 after use. The manner of adhesion between the reinforcing sheet 22 and the device layer 20 via the adhesive layer is not particularly limited and may be, for example, mechanical bonding (i.e., adhesion by anchoring effect), physical interaction (i.e., adhesion by van der Waals forces), chemical bonding, etc. Examples of adhesive materials included in the adhesive layer include phenolic resin, urea resin, melamine resin, epoxy resin, polyimide resin, ethylene-vinyl acetate copolymer resin (EVA), urethane resin, acrylic resin, synthetic rubber, and starch, preferably thermosetting epoxy resin, thermosetting polyimide resin, photosensitive polyimide resin, acrylic resin, phenolic resin, or a combination thereof, more preferably thermosetting epoxy resin, thermosetting polyimide resin, acrylic resin, phenolic resin, or a combination thereof. The adhesive layer preferably has a thickness of 1 μm to 2000 μm, more preferably 3 μm to 1000 μm, even more preferably 5 μm to 800 μm, and particularly preferably 10 μm to 500 μm. Such a thickness makes it easier to control the adhesion to the device layer 20 within a desired range, and allows for quick peeling and removal of the reinforcing sheet 22 after use.

[0025] If desired, other layers such as an intermediate layer, release layer, or metal layer may be interposed between the reinforcing sheet 22 and the adhesive layer. For example, the adhesive layer, metal layer, release layer, intermediate layer, and reinforcing sheet 22 may be laminated on the device layer 20 in this order. The configurations of the intermediate layer, release layer, and metal layer are not particularly limited, and may, for example, conform to the preferred configurations of the intermediate layer 14, release layer 16, and metal layer 18 described later with respect to the laminate 10.

[0026] (4) Fixing the laminate to the peeling device As shown in Figures 1(iii) and 2(iv), the laminate 10 is fixed to the peeling device 24. The peeling device 24 includes a first diaphragm 26 having a mounting surface 26a for placing the laminate 10, and a first pressurizing means 28 capable of applying pressure to the first diaphragm 26 from the side opposite to the mounting surface 26a of the first diaphragm. The laminate 10 is fixed to the peeling device 24 so that the carrier 12 and the mounting surface 26a of the first diaphragm are in contact. The fixing method is not particularly limited, and the laminate 10 can be preferably fixed to the peeling device 24 by using fixing jigs such as clamps, adhesive components such as adhesives and tapes, or means of fitting the end of the laminate 10 into grooves formed in the peeling device 24.

[0027] In this specification, "diaphragm" means a membrane that can be deformed in response to the action of pressure. The first diaphragm 26 is typically made of a flexible material (soft material) and can maintain the desired adhesion with the carrier 12 by expanding under pressure. From this viewpoint, the first diaphragm is preferably made of an elastic material such as rubber, and more preferably of silicone rubber, ethylene propylene rubber, isoprene rubber, chloroprene rubber, chlorosulfonated rubber, nitrile rubber, styrene butadiene rubber, chlorinated polyethylene, fluororubber, EPDM (ethylene propylene diene rubber), PTFE (polytetrafluoroethylene), or a combination thereof. Furthermore, the first diaphragm 26 is preferably made of a material with a thickness of 1 mm or more and a thickness of 20 mm or less. By selecting the material, hardness and / or thickness of the first diaphragm 26 in this way, it becomes easier to apply the desired stress to the carrier 12 in the process described later. From the viewpoint of desirablely ensuring close contact between the first diaphragm 26 and the carrier 12, it is preferable that the mounting surface 26a of the first diaphragm is larger than the outermost surface of the carrier 12 (the surface opposite to the release layer 16). The shape of the film of the first diaphragm can optionally be a film with uneven thickness. For example, the diaphragm may have a shape in which the edges of the film are the thickest and the thickness decreases towards the center of the film. In this case, changes in the shape of the edges are less likely to occur, while changes in the shape of the center can be easily made.

[0028] The first pressurizing means 28 is not particularly limited, as long as it can pressurize the first diaphragm 26 at a desired pressure. For example, it can be a compressor or the like that sends compressed air to the side of the first diaphragm opposite the mounting surface 26a, or a pump that applies water pressure, hydraulic pressure, or pneumatic pressure to the side of the first diaphragm 26 opposite the mounting surface 26a. As the pressure medium, an incompressible fluid such as water or oil, or a compressible fluid such as air or other gases can be used, and is not particularly limited as long as it is a fluid. When the peel strength of the laminate 10 is low or when the area of ​​the laminate 10 is large and the vertical deformation is relatively large, a compressible fluid such as gas is preferably used, and in the opposite case, an incompressible fluid such as liquid is preferably used. Alternatively, the first diaphragm 26 can be desirablely expanded by creating a pressure difference between the pressure applied to the side of the first diaphragm opposite the mounting surface 26a and the ambient pressure in the environment in which the laminate 10 is placed, in other words, the ambient pressure in the environment in which the peeling device 24 is placed. Therefore, for example, the first pressurizing means 28 may also use means that create the above-mentioned pressure difference, such as a pressurizing chamber and / or a depressurizing chamber. In a preferred embodiment, the surface opposite to the mounting surface 26a of the first diaphragm is pressurized by increasing the pressure applied to the surface opposite to the mounting surface 26a of the first diaphragm compared to the pressure applied to the mounting surface 26a of the first diaphragm, or by decreasing the pressure applied to the mounting surface 26a of the first diaphragm compared to the pressure applied to the surface opposite to the mounting surface 26a of the first diaphragm. Specifically, as shown in Figure 1(iii), the peeling device 24 is obtained by fixing the first diaphragm 26 to the container under atmospheric pressure or in a pressurizing chamber such that the surface opposite to the mounting surface 26a of the first diaphragm forms a sealed space with the container, and the mounting surface 26a is exposed to the outside of the container. Subsequently, the laminate 10 is fixed to the mounting surface 26a of the first diaphragm, and the peeling device 24 is moved to a reduced pressure chamber or under atmospheric pressure (when the first diaphragm 26 is fixed to the container in a pressurized chamber). By doing so, the pressure applied to the surface opposite to the mounting surface 26a (i.e., the pressure of the sealed space inside the container) becomes greater than the pressure applied to the mounting surface 26a (i.e., the outside air pressure), and as a result, the surface opposite to the mounting surface 26a can be pressurized.

[0029] (5) Pressurizing the diaphragm As shown in Figure 2(v), the first diaphragm 26 is pressurized and expanded using the first pressurizing means 28 from the side opposite to the mounting surface 26a of the first diaphragm. This changes the shape of the carrier 12 or the laminate 10. When the first diaphragm 26 is pressurized, the displacement due to expansion is greater at the center of the first diaphragm 26 than at the outer circumference. In other words, the first diaphragm 26 undergoes a three-dimensional shape change when pressurized. As a result, the carrier 12 in contact with the first diaphragm 26 is also subjected to three-dimensional stress due to the expansion of the first diaphragm 26, which in turn causes a change in the shape of the carrier 12, etc. Thus, because the present invention utilizes the three-dimensional stress due to the expansion of the diaphragm, the stress applied to the carrier 12 is made uniform, and therefore, damage or defects to the carrier 12 and / or device layer 20 caused by locally applied stress can be effectively suppressed. When the reinforcing sheet 22 is pre-laminated on the device layer 20, as described above, changes in the shape of the device layer 20 (e.g., curvature) are suppressed, and typically, the shape of the carrier 12 changes primarily. On the other hand, when the reinforcing sheet 22 is not pre-laminated, the shape of not only the carrier 12 but also the device layer 20 may change.

[0030] The shape change of the carrier 12 or the laminate 10 is preferably such that the outer surface of the carrier 12 (the surface facing the first diaphragm 26) becomes concave, as shown in Figure 2(v). However, it is also possible that, before pressurizing the first diaphragm 26, the laminate 10 may already be warped such that the outer surface of the carrier 12 becomes convex due to the formation of the device layer 20 or the like. In such a case, the shape change may be such that the curvature of the carrier 12 or the laminate 10 is corrected so that the outer surface of the carrier 12 becomes flat.

[0031] Preferably, the maximum difference between the pressure applied to the surface of the first diaphragm 26 opposite to the mounting surface 26a (e.g., pressurized pressure or pressure in a sealed space) and the pressure applied to the mounting surface 26a (e.g., ambient air pressure) is 0.00010 MPa or more and 5.0 MPa or less, more preferably 0.001 MPa or more and 3.0 MPa or less, even more preferably 0.01 MPa or more and 2.0 MPa or less, and particularly preferably 0.1 MPa or more and 1.0 MPa or less. This makes it easier to control the expansion of the first diaphragm 26 within a desired range, and therefore makes it easier to control the shape change of the carrier 12 or the laminate 10 within a desirable range.

[0032] (6) Separation of carrier and device layer As shown in Figure 2(vi), the shape change of the carrier 12 is utilized to generate shear stress between the carrier 12 and the device layer 20, thereby separating the device layer 20 from the laminate 10 at the location of the delamination layer 16. Note that the pressurization process on the diaphragm described in (5) above and this process may be performed continuously. That is, separation of the carrier 12 and the device layer 20 during the pressurization process on the first diaphragm 26 is permissible.

[0033] The delamination mechanism of the carrier 12 and / or device layer 20 in the present invention is not entirely clear, but it is thought to be as follows. Here, Figure 6 shows a schematic diagram illustrating the stress applied to each layer when a shape change occurs in the laminate 10. First, as shown in Figures 6(i) and (ii), a force is applied to the laminate 10 in a direction that causes the outer surface of the carrier 12 to contract, and / or a force that causes the outer surface of the device layer 20 to stretch, causing the laminate 10 to bend or deform. At this time, as shown in Figure 6(ii), a compressive stress is applied to the carrier 12 in a direction toward the center of the carrier, and a tensile stress is applied to the device layer 20 in a direction toward the outer circumference of the device layer. In other words, stresses in opposite directions are applied to the carrier 12 and the device layer 20. For this reason, as shown in Figure 6(iii), shear stress is generated in the delamination layer 16 interposed between the carrier 12 and the device layer 20 due to the above compressive and tensile stresses. Then, the shear stress causes the delamination layer 16 to break at least partially, separating the carrier 12 and the device layer 20. Even when the carrier 12 changes shape so that its outer surface changes from a convex surface to a flat surface, as described above, it is believed that the separation of the carrier 12 and the device layer 20 proceeds by the same mechanism as described above. Thus, according to the present invention, the carrier 12 and the device layer 20 can be easily separated by utilizing the shape change of the carrier 12, etc., due to the expansion of the diaphragm, without requiring complex processes. If the carrier 12 and / or the device layer 20 are only partially separated (i.e., only a part of the delamination layer 16 is broken), the carrier 12 and / or the device layer 20 may be completely separated by gripping them with your hands or tools and pulling them apart.

[0034] The device layer 20 peeled off from the laminate 10 may be used as a substrate for the final product as is, or it may be used as a substrate after further processing of various known treatments on the device layer 20. For example, if a reinforcing sheet 22 is laminated on the device layer 20, it is preferable to peel off the reinforcing sheet 22 from the device layer 20 after removing the carrier 12. In this regard, if the reinforcing sheet 22 is laminated via an adhesive layer, the adhesive layer can be dissolved or softened by contacting it with a solution that can dissolve the adhesive layer, thereby removing the reinforcing sheet 22. Furthermore, if necessary, a process such as mounting an electronic element such as a chip on the device layer 20 (e.g., second redistribution layer 20c) may be performed. By laminating multiple IC packages together with the chip C that can be embedded in the device layer 20 (e.g., molded resin layer 20b) described above and mounting them on the substrate, the integration density can be improved. Furthermore, a solder resist or mounting bumps may be formed on the outer surface of the device layer 20.

[0035] <Other Embodiments of Substrate Manufacturing Method> Figures 7 and 8 show another example of the substrate manufacturing method of the present invention. As shown in Figure 7(i), the peeling apparatus 24 used in this embodiment further comprises, in addition to the first diaphragm 26 and first pressurizing means 28 described above, a second diaphragm 30 having a support surface 30a facing the mounting surface 26a of the first diaphragm, and a second pressurizing means 32 capable of pressurizing the second diaphragm from the surface opposite to the support surface 30a of the second diaphragm. Preferred embodiments of the second diaphragm 30 and the second pressurizing means 32 are the same as the preferred embodiments described above with respect to the first diaphragm 26 and the first pressurizing means 28, respectively.

[0036] The laminate 10 is preferably fixed using the peeling device 24 of this embodiment in the following manner. First, as shown in Figure 7(ii), the laminate 10 is sandwiched between the first diaphragm 26 and the second diaphragm 30 such that the carrier 12 and the mounting surface 26a of the first diaphragm are in contact, and the device layer 20 and the support surface 30a of the second diaphragm are in contact. Next, as shown in Figure 8(iii), the laminate 10 is sandwiched between the first diaphragm 26 and the second diaphragm 30 by applying pressure to the first diaphragm 26 from the side opposite to the mounting surface 26a of the first diaphragm using the first pressing means 28, and applying pressure to the second diaphragm 30 from the side opposite to the support surface 30a of the second diaphragm using the second pressing means 32. In this way, the laminate 10 is pressed from both sides by the two diaphragms that contact it, resulting in the laminate 10 being fixed between the first diaphragm 26 and the second diaphragm 30. Thus, in this embodiment, since the laminate 10 is fixed by being sandwiched between the two diaphragms, there is an advantage that the laminate 10 does not need to be limited to a specific shape. In this respect, conventional peeling devices sometimes require design according to the shape of the substrate, and may not be applicable to substrates other than the target shape. In contrast, the peeling device 24 of this embodiment prepares a first diaphragm 26 and a second diaphragm 30 that are larger in size than the laminate 10 when viewed from above, so that the laminate 10 can be sandwiched between these two diaphragms. For this reason, it is possible to fix the laminate 10 regardless of its shape by the method described above.

[0037] As shown in FIG. 8(iv), the step of changing the shape of the laminate 10 preferably includes expanding the first diaphragm by increasing the pressing pressure applied to the first diaphragm 26 as compared with the pressing pressure applied to the second diaphragm 30. Alternatively, the first diaphragm 26 may be expanded by reducing the pressing pressure applied to the second diaphragm 30 as compared with the pressing pressure applied to the first diaphragm 26, thereby changing the shape of the laminate 10. In any case, the first diaphragm 26 can be expanded by controlling the pressing pressure applied to the first diaphragm 26 to be greater than the pressing pressure applied to the second diaphragm 30. In this embodiment, since the laminate 10 is sandwiched between two diaphragms, it is typical that not only the carrier 12 but also the entire shape of the laminate 10 including the device layer 20 changes (e.g., curves). Further, the step of fixing the laminate 10 described above to the peeling device 24 and this step may be performed continuously. That is, by continuously controlling the pressing pressure applied to the first diaphragm 26 and the pressing pressure applied to the second diaphragm (e.g., gradually increasing the pressing pressure), it may be possible to continuously perform from the fixing of the laminate 10 to the shape change (further separation of the carrier 12 and the device layer 20). The difference between the pressing pressure applied to the first diaphragm 26 and the pressing pressure applied to the second diaphragm 30 may be appropriately set so as to be within a range in which the carrier 12 can be peeled off, and is not particularly limited.

[0038] Regarding the other steps (e.g., the step of separating the carrier and the device layer) described above while referring to FIGS. 1 and 2, the same applies as in this embodiment. After the separation of the carrier 12 and the device layer 20, by stopping the pressing on the first diaphragm 26 and the second diaphragm 30, the device layer 20 etc. can be taken out from the peeling device 24.

[0039] The peeling apparatus 24 of this embodiment can also be preferably used to separate the carrier and the device layer in a laminate (i.e., a double-sided substrate) in which device layers are formed on both sides of the carrier. Figure 9 shows an example of a method for peeling a double-sided substrate using the peeling apparatus. As shown in Figure 9(i), the laminate 10 as a double-sided substrate further comprises, in addition to the carrier 12, peeling layer 16 and device layer 20 described above, a second peeling layer 17 provided on the side of the carrier 12 opposite to the peeling layer 16, and a second device layer 21 provided on the side of the second peeling layer 17 opposite to the carrier 12.Optionally, the laminate 10 may have an additional intermediate layer (not shown) between the carrier 12 and the second peeling layer 17, and an additional metal layer (not shown) between the second peeling layer 17 and the second device layer 21. Preferred embodiments of the additional intermediate layer, the second peeling layer 17, the additional metal layer, and the second device layer 21 are the same as preferred embodiments of the intermediate layer 14, the peeling layer 16, the metal layer 18, and the device layer 20, respectively.

[0040] By changing the shape of the laminate 10 as a double-sided substrate as follows, it is preferable to peel the two device layers from the laminate 10. That is, as shown in FIGS. 9(ii) and (iii), the process of changing the shape of the laminate 10 preferably includes both inflating the first diaphragm 26 and inflating the second diaphragm 30. The inflation of the first diaphragm 26 can be preferably performed by increasing the pressure applied to the first diaphragm 26 compared to the pressure applied to the second diaphragm 30, or by decreasing the pressure applied to the second diaphragm 30 compared to the pressure applied to the first diaphragm 26. By doing so, for example, the outermost surface (the surface on the side of the second diaphragm 30) of the device layer 20 becomes convex, and the outermost surface (the surface on the side of the first diaphragm 26) of the second device layer 21 becomes concave, and the shape of the laminate 10 changes (see FIG. 9(ii)). On the other hand, the inflation of the second diaphragm 30 can be preferably performed by increasing the pressure applied to the second diaphragm 30 compared to the pressure applied to the first diaphragm 26, or by decreasing the pressure applied to the first diaphragm 26 compared to the pressure applied to the second diaphragm 30. By doing so, for example, the outermost surface of the device layer 20 becomes concave, and the outermost surface of the second device layer 21 becomes convex, and the shape of the laminate 10 changes (see FIG. 9(iii)). The order of inflating the diaphragms is not limited. For example, the first diaphragm 26 may be inflated after the second diaphragm 30 is inflated.

[0041] The preferable range of the maximum difference between the pressure applied to the first diaphragm 26 and the pressure applied to the second diaphragm 30 when inflating the first diaphragm 26 is as described above. Also, the preferable range of the maximum difference between the pressure applied to the second diaphragm 30 and the pressure applied to the first diaphragm 26 when inflating the second diaphragm 30 is the same as the preferable range when inflating the first diaphragm 26.

[0042] Furthermore, by utilizing the shape change of the laminate 10, shear stress is generated between the carrier 12 and the device layer 20, and also between the carrier 12 and the second device layer 21. As a result, the device layer 20 can be peeled off from the laminate 10 at the location of the release layer 16, and the second device layer 21 can be peeled off from the laminate 10 at the location of the second release layer 17.

[0043] Laminate As described above, the laminate 10 used in the method of the present invention may comprise, in order, a carrier 12, an optional intermediate layer 14, a release layer 16, an optional metal layer 18, and a device layer 20. Each of the intermediate layer 14, the release layer 16, and the metal layer 18 may be a single layer or a multilayer consisting of two or more layers. Furthermore, the laminate 10 may be in the form of a double-sided substrate, as described above with reference to Figure 9(i). Preferred embodiments of the carrier 12, intermediate layer 14, release layer 16, and metal layer 18 will be described below.

[0044] As described above, the carrier 12 is preferably composed of glass, silicon, metal, ceramics, or a combination thereof. When glass is used as the carrier 12, it has advantages such as being lightweight, having a low coefficient of thermal expansion, high insulating properties, being rigid and having a flat surface, which allows the surface of various layers laminated on the carrier 12 to be extremely smooth. Furthermore, when the carrier 12 is glass, it has advantages such as having surface flatness (coplanarity) that is advantageous for forming fine circuits, and having chemical resistance in desmear in the wiring manufacturing process and in various plating processes. Preferred examples of glass constituting the carrier 12 include quartz glass, borosilicate glass, alkali-free glass, soda-lime glass, aluminosilicate glass, and combinations thereof, more preferably alkali-free glass, soda-lime glass, and combinations thereof, and particularly preferably alkali-free glass. Alkali-free glass is a glass that is substantially free of alkali metals, with silicon dioxide, aluminum oxide, boron oxide, and alkaline earth metal oxides such as calcium oxide and barium oxide as its main components, and further containing boric acid. This alkali-free glass has the advantage of minimizing glass warping during heating processes because its thermal expansion coefficient 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.

[0045] The silicon-based carrier 12 can be any silicon containing the element Si, such as SiO ２Substrates such as SiN substrates, Si single-crystal substrates, and Si polycrystalline substrates can be used. Preferred examples of metals constituting the carrier 12 include copper, titanium, nickel, stainless steel, and aluminum. Preferred examples of ceramics constituting the carrier 12 include alumina, zirconia, silicon nitride, aluminum nitride, and various other fine ceramics. More preferably, from the viewpoint of preventing warping of the coreless support due to heating when mounting semiconductor elements, the material has 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 the glass, silicon, metal and ceramics mentioned above. Furthermore, from the viewpoint of handling and ensuring flatness when mounting chips, the carrier 12 preferably has a Vickers hardness of 100 HV or more, and more preferably 150 HV or more and 2500 HV or less. As a material that satisfies these characteristics, the carrier 12 is preferably composed of glass, silicon, metal or ceramics.

[0046] The carrier 12 may take the form of a sheet, film, or plate. Alternatively, the carrier 12 may be a laminate of these sheets, films, and plates. For example, the carrier 12 may function as a rigid support such as a glass plate, ceramic plate, silicon wafer, or metal plate, or it may be a non-rigid form such as a metal foil. According to a preferred embodiment of the present invention, the carrier 12 is disc-shaped with a diameter of 100 mm or more, and more preferably disc-shaped with a diameter of 200 mm or more and 450 mm or less. The carrier 12 (e.g., a Si single crystal substrate) may have a notch or orientation flat (also called an orientation flat) to indicate a reference point for the crystal orientation. Generally, an orientation flat is formed when the diameter of the carrier 12 is 200 mm or less, and a notch is formed when the diameter is 200 mm or more. According to another preferred embodiment of the present invention, the carrier 12 is rectangular with a short side of 100 mm or more, and more preferably with a short side of 150 mm or more and 650 mm or less. The rectangular carrier 12 may have a long side that is sufficiently longer than its short side, but preferably the long side is 200 mm or more and 650 mm or less.

[0047] The intermediate layer 14 is an optional layer 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 sometimes referred to as metal M). Preferably, it is Cu, Ti, Al, Nb, Zr, Cr, W, Ta, Co, Ag, Ni, Mo, and combinations thereof; more preferably, it is Cu, Ti, Zr, Al, Cr, W, Ni, Mo, and combinations thereof; even more preferably, it is Cu, Ti, Al, Ni, Mo, and combinations thereof; and particularly preferably, it is 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 resulting from the raw material components or the film formation process. While 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 formed by physical vapor deposition (PVD), and more preferably by sputtering. From the viewpoint of uniformity of film thickness distribution, the intermediate layer 14 is particularly preferably 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 with a roughness equivalent to that of the carrier. This thickness is determined by analyzing the layer cross-section using an energy-dispersive X-ray spectrometer (TEM-EDX) on a transmission electron microscope.

[0048] 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., an alloy or an intermetallic compound), more preferably Al, Ti, or a combination thereof (e.g., an alloy or an intermetallic compound), and even more preferably a layer mainly containing Al or a layer mainly containing Ti. On the other hand, when using a metal or alloy that does not have sufficiently high adhesion to the carrier 12 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, a preferred example of a two-layer configuration for the 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 configuration also changes the release 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 release properties of the carrier. Therefore, the intermediate layer 14 can also be said to be a layer mainly containing metal M. From the above, the metal M content in the intermediate layer 14 is preferably 50 atomic% to 100 atomic%, more preferably 60 atomic% to 100 atomic%, even more preferably 70 atomic% to 100 atomic%, particularly preferably 80 atomic% to 100 atomic%, and most preferably 90 atomic% to 100 atomic%.

[0049] 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.

[0050] 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 removable by a method that applies physical force, or it may be removable by a laser method (laser lift-off, LLO). If the release layer 16 is made of a material that can be removed by laser lift-off, the release layer 16 may be made of a resin whose interfacial adhesion strength decreases when irradiated with a laser beam after curing, or it may be a layer of silicon, silicon carbide, metal oxide, etc. that is modified by laser beam irradiation. Furthermore, 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, carboxylic acids, etc. Examples of nitrogen-containing organic compounds include triazole compounds, imidazole compounds, etc. 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, or Ga, or a carbon layer. Among these, the release layer 16 is particularly 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 composed 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% 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 of the carbon concentration is not particularly limited and may be 100 atomic%, but 98 atomic% or less is practical. The release layer 16 may contain impurities (for example, oxygen, hydrogen, etc., derived from the surrounding environment such as the atmosphere). Furthermore, due to the film formation method used for the metal layer 18 and other materials, metal atoms of types other than the metal contained in the release layer 16 may be mixed into the release layer 16.When a carbon-containing layer is used as the release layer 16, it exhibits low interdiffusivity and reactivity with carriers. Even when subjected to press working at temperatures exceeding 300°C, it prevents the formation of metallic bonds between the metal layer and the bonding interface due to high-temperature heating, thus maintaining a state where carrier peeling and removal is easy. It is preferable that this release layer 16 is also formed by a vapor phase method such as sputtering, in terms of suppressing excessive impurities in the release layer 16 and enabling continuous productivity with the deposition of an 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 setting the thickness to this extent, it is possible to create a release layer that has a roughness equivalent to that of the carriers and possesses a release function. This thickness is measured by analyzing the layer cross-section with an energy-dispersive X-ray spectrometer (TEM-EDX) on a transmission electron microscope.

[0051] 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 laminate 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, so that stable release properties can be maintained even after heating at high temperatures of, for example, 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 or more and 100 nm or less. 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) in which the boundary between the metal oxide layer and the carbon-containing layer is not clearly defined.

[0052] 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 percent or more, and preferably the (F+N) region is located on the metal layer 18 side of the metal-containing layer. Thickness of the (F+N) region (SiO ２The (converted) value is determined by performing elemental analysis of the laminate 10 in the depth direction using XPS. The fluorinated or nitrided surface can preferably be formed by reactive ion etching (RIE) or reactive sputtering. On the other hand, the metal elements contained in the metal-containing layer preferably have a negative standard electrode potential. Preferred examples of metal elements contained 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 content of metal elements 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 consisting of one layer, or a multilayer consisting 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 determined by analyzing the cross-section of the layer with an energy-dispersive X-ray spectrometer (TEM-EDX) on a transmission electron microscope.

[0053] 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 cross-section of the layer with an energy-dispersive X-ray spectrometer (TEM-EDX) on a transmission electron microscope.

[0054] The metal layer 18 is a layer made of metal. The metal layer 18 may be a single layer or a layer of two or more. When the metal layer 18 is made up of two or more layers, the metal layer 18 can be configured such that each metal layer from the first metal layer to the mth metal layer (where m is an integer of 2 or more) is sequentially stacked on the side of the release layer 16 opposite to the carrier 12. The total thickness of the metal layer 18 is preferably 1 nm to 2000 nm, more preferably 100 nm to 1500 nm, more preferably 200 nm to 1000 nm, even more preferably 300 nm to 800 nm, and particularly preferably 350 nm to 500 nm. The thickness of the metal layer 18 is measured by analyzing the cross-section of the layer with an energy-dispersive X-ray spectrometer (TEM-EDX) on a transmission electron microscope. Below, an example in which the metal layer 18 is made up of two layers, a first metal layer and a second metal layer, will be described.

[0055] The first metal layer preferably provides the laminate 10 with desired functions such as an etching stopper function and an anti-reflective function. Preferred examples of metals constituting the first metal layer 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 being poorly soluble 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 first metal layer is less susceptible to etching by flash etching solutions than the second metal layer described later, and thus can function as an etching stopper layer that can delay the progress of etching. Furthermore, since the metal constituting the first metal layer also has the function of preventing light reflection, the first metal layer can also function as an anti-reflective layer to improve visibility in image inspection (for example, automated image inspection (AOI)). The first metal layer may be a pure metal or an alloy. The metal constituting the first metal layer may contain 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 first metal layer is preferably a layer formed by physical vapor deposition (PVD), and more preferably a layer formed by sputtering. The thickness of the first metal layer 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.

[0056] Preferred examples of metals constituting the second metal layer include transition elements of Groups 4, 5, 6, 9, 10, and 11, Al, and combinations thereof (e.g., alloys and intermetallic compounds). More preferably, transition elements of Groups 4 and 11, Al, Nb, Co, Ni, Mo, and combinations thereof. Even more preferably, transition elements of Group 11, Ti, Al, Mo, and combinations thereof. Particularly preferred are Cu, Ti, Mo, and combinations thereof. Most preferably, Cu. The second metal layer may be manufactured by any method, for example, a metal foil formed by wet deposition 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. A particularly preferred second metal layer 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 an unroughened metal layer is preferred for the second metal layer, it may also be subjected to secondary roughening treatments such as preliminary roughening, soft etching, cleaning, or oxidation-reduction treatment, as long as it does not hinder wiring pattern formation. From the viewpoint of accommodating fine pitch reduction, the thickness of the second metal layer is preferably 10 nm to 1000 nm, more preferably 20 nm to 900 nm, even more preferably 30 nm to 700 nm, even more preferably 50 nm to 600 nm, particularly preferably 70 nm to 500 nm, and most preferably 100 nm to 400 nm. Metal layers with thicknesses within this range are preferably manufactured by sputtering from the viewpoint of in-plane uniformity of film thickness and productivity in sheet or roll form.

[0057] When the metal layer 18 has a single-layer structure, it is preferable to use the second metal layer described above as the metal layer 18. On the other hand, when the metal layer 18 has an n-layer structure (where n is an integer of 3 or more), it is preferable to have the first metal layer to the (n-1)th metal layer of the metal layer 18 have the configuration of the first metal layer described above, and the outermost layer of the metal layer 18, i.e., the nth metal layer, have the configuration of the second metal layer described above.

[0058] The intermediate layer 14 (if present), the release layer 16, 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.

[0059] It is preferable that the metal layer 18, an optional intermediate layer 14, and an optional release layer 16 (i.e., 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. In other words, 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 chemical solutions from penetrating the carrier 12 during the manufacturing process of the wiring board, and it is also possible to firmly prevent chipping due to peeling at the side edges when handling the laminate 10, i.e., chipping of the film on the release layer 16 (i.e., the metal layer 18). The covered area on 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 even more preferably extends over the entire end face of the carrier 12, in the thickness direction (i.e., the direction perpendicular to the carrier surface) from the surface of the carrier 12.

[0060] The overall thickness of the laminate 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 especially preferably 1000 μm to 1700 μm. The size of the laminate 10 is not particularly limited, but is preferably 10 cm or larger in diameter or 10 cm square or larger, more preferably 20 cm or larger in diameter or 20 cm square or larger, and even more preferably 25 cm or larger in diameter or 25 cm square or larger. The upper limit of the size of the laminate 10 is not particularly limited, but a diameter of 1000 cm or 1000 cm square can be cited as one guideline for the upper limit. Furthermore, the laminate 10 is in a form that can be handled independently before and after the formation of the device layer 20.

[0061] 10 Laminate 12 Carrier 14 Intermediate layer 16 Release layer 17 Second release layer 18 Metal layer 20 Device layer 20a First redistribution layer 20b Molding resin layer 20c Second redistribution layer 21 Second device layer 22 Reinforcement sheet 24 Release device 26 First diaphragm 28 First pressurizing means 30 Second diaphragm 32 Second pressurizing means C Chip P Pillar

Claims

1. A method for manufacturing a substrate, comprising: a step of preparing a laminate having a release layer and a device layer in order on a carrier; a step of fixing the laminate to a release device, wherein the release device comprises a first diaphragm having a mounting surface for placing the laminate, and a first pressurizing means capable of pressurizing the first diaphragm from the surface of the first diaphragm opposite to the mounting surface, and the fixing of the laminate to the release device is performed such that the carrier and the mounting surface of the first diaphragm are in contact; a step of using the first pressurizing means to pressurize and expand the first diaphragm from the surface of the first diaphragm opposite to the mounting surface, thereby changing the shape of the carrier or the laminate; and a step of utilizing the change in the shape of the carrier to generate shear stress between the carrier and the device layer, thereby peeling the device layer from the laminate at the position of the release layer.

2. The method for manufacturing a substrate according to claim 1, wherein the maximum difference between the pressure applied to the surface of the first diaphragm opposite to the mounting surface and the pressure applied to the mounting surface is 0.00010 MPa or more and 5.0 MPa or less.

3. The peeling device further comprises a second diaphragm having a support surface facing the aforementioned mounting surface of the first diaphragm, and a second pressurizing means capable of pressurizing the second diaphragm from the side of the second diaphragm opposite to the support surface, and the step of fixing the laminate to the peeling device includes (i) sandwiching the laminate between the first diaphragm and the second diaphragm such that the carrier and the aforementioned mounting surface of the first diaphragm are in contact, and the device layer and the support surface of the second diaphragm are in contact, and (ii) pressing the first diaphragm from the side of the first diaphragm opposite to the aforementioned mounting surface using the first pressurizing means, and pressing the second diaphragm from the side of the second diaphragm opposite to the support surface using the second pressurizing means, thereby sandwiching the laminate between the first diaphragm and the second diaphragm. The method for manufacturing a substrate according to claim 1, wherein the step of changing the shape of the laminate includes increasing the pressure applied to the first diaphragm relative to the pressure applied to the second diaphragm, or decreasing the pressure applied to the second diaphragm relative to the pressure applied to the first diaphragm, thereby causing the first diaphragm to expand and changing the shape of the laminate.

4. The laminate further comprises a second release layer provided on the side of the carrier opposite to the release layer, and a second device layer provided on the side of the second release layer opposite to the carrier, wherein the step of changing the shape of the laminate includes (i) increasing the pressure applied to the first diaphragm relative to the pressure applied to the second diaphragm, or decreasing the pressure applied to the second diaphragm relative to the pressure applied to the first diaphragm, thereby causing the first diaphragm to expand and thereby changing the shape of the laminate, and (ii) increasing the pressure applied to the second diaphragm relative to the pressure applied to the first diaphragm, or decreasing the pressure applied to the first diaphragm relative to the pressure applied to the second diaphragm, thereby causing the second diaphragm to expand and thereby changing the shape of the laminate, The method for manufacturing a substrate according to claim 3, further comprising the step of peeling off the device layer, which involves utilizing the shape change of the laminate to generate shear stress between the carrier and the second device layer, thereby peeling off the second device layer from the laminate at the location of the second peel layer.

5. The method for manufacturing a substrate according to claim 1, further comprising the step of laminating a reinforcing sheet on the device layer before changing the shape of the carrier.

6. The method for manufacturing a substrate according to claim 5, wherein when the shape of the carrier is changed, the reinforcing sheet and the device layer supported by it are not bent, and the device layer is peeled off from the laminate by changing the shape of the portion of the laminate other than the device layer.

7. A method for manufacturing a substrate according to any one of claims 1 to 6, further comprising the step of performing a trimming process on the device layer before fixing the laminate to the peeling device, wherein the trimming process is performed by making cuts that pass inside the contour of the device layer when the laminate is viewed from above, and that penetrate the device layer when the laminate is viewed in cross-section.

8. The method for manufacturing a substrate according to any one of claims 1 to 6, wherein the laminate further comprises a metal layer provided between the release layer and the device layer.

9. A method for manufacturing a substrate according to any one of claims 1 to 6, wherein the carrier is composed of glass, silicon, metal, or ceramics.

10. A method for manufacturing a substrate according to any one of claims 1 to 6, wherein the carrier has a thickness of 3,000 μm or less.

11. A method for manufacturing a substrate according to any one of claims 1 to 6, wherein the device layer includes a wiring layer, an electronic element provided on the wiring layer, and a molded resin layer that embeds the wiring layer and the electronic element.

12. When the thickness direction of the laminate is taken as the projection direction, the projected area of ​​the laminate is 1,000 mm². ２ The above is 1,000,000 mm ２ The method for manufacturing a substrate according to any one of claims 1 to 6, as follows:

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