Manufacturing method for multilayer wiring boards

Abstract

To provide a manufacturing technology for a multilayer wiring board capable of forming a through-hole with less variation.SOLUTION: One manufacturing method for a multilayer wiring board according to the present invention is to form a through hole in a glass substrate having a first surface and a second surface opposite to the first surface. The method has a bonding step for forming a bonding layer between a first support and the glass substrate and bonding the second surface of the glass substrate and the first support via the bonding layer, a modified portion forming step for forming a laser modified portion on the glass substrate by irradiating the glass substrate from the first surface side with a laser, a first support peeling step for peeling the first support from the glass substrate, and a through-hole forming step for forming a through-hole by etching from the second surface side of the glass substrate. The bonding layer includes an absorbing material having a transmittance greater than or equal to a predetermined value with respect to the wavelength of the laser.SELECTED DRAWING: Figure 12

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a multilayer wiring board.

Background Art

[0002] In recent years, with the progress of miniaturization of electronic devices, further thinning is also required for multilayer wiring boards represented by interposers mounted in electronic devices. In particular, some recent multilayer wiring boards adopt a glass substrate as a core substrate. As a method for manufacturing such a multilayer wiring board, through-holes are formed in a glass substrate to provide through electrodes, and conductor layers, insulating resin layers, conductor layers, ... are sequentially laminated on both sides of the glass substrate.

[0003] It is generally difficult to process a thin substrate with high accuracy while handling it as it is. Therefore, for example, in Patent Document 1, in order to more easily provide a glass device having a thin glass substrate with a glass thickness of 300 µm or less, after forming wiring on one surface of the glass substrate, a manufacturing method in which formation of through-holes and thinning of the glass substrate are simultaneously performed by etching is disclosed. In this manufacturing method, since thinning of the glass and formation of through-holes are performed in a state where the glass substrate is supported by a glass carrier, the ease of handling the glass substrate when forming circuits and the like on the glass substrate is improved, making it possible to stably form conductor layers and insulating resin layers.

Prior Art Literature

Patent Literature

[0004]

Patent Literature 1

Summary of the Invention

Problem to be Solved by the Invention

[0005] In Patent Document 1, to form through-holes in a glass substrate, a laser-modified section was formed, and then the glass substrate was bonded to a glass carrier, which served as a support, before proceeding with the manufacturing process. However, with this method, the laser-modified section could not be formed uniformly in the thickness direction of the glass substrate, resulting in variations in the through-holes after the subsequent etching process. Furthermore, because handling thin glass substrates is difficult, a certain thickness was required for the glass substrate, hindering further thinning.

[0006] Therefore, the present invention aims to provide a manufacturing technology for multilayer wiring boards that can form through holes with minimal variation. [Means for solving the problem]

[0007] To solve the above problems, one representative method for manufacturing a multilayer wiring substrate of the present invention is a method for manufacturing a multilayer wiring substrate having a first surface and a second surface facing the first surface, wherein the method comprises: an adhesion step of forming an adhesive layer between a first support and the glass substrate and bonding the second surface of the glass substrate and the first support via the adhesive layer; a modification step of irradiating the glass substrate with a laser from the first surface side to form a laser-modified portion in the glass substrate; a first support peeling step of peeling the first support from the glass substrate; and a through-hole forming step of etching the glass substrate from the second surface side to form a through-hole, wherein the adhesive layer contains an absorbing material having a transmittance of a predetermined value or more with respect to the wavelength of the laser. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a multilayer wiring board that can form through holes with less variation. Other issues, structures, and effects not mentioned above will be clarified by the following explanation of the implementation methods. [Brief explanation of the drawing]

[0009] [Figure 1]Figure 1 shows the bonding step of the first support in the manufacturing method according to the first embodiment. [Figure 2] Figure 2 shows the laser modification process in the manufacturing method according to the first embodiment. [Figure 3] Figure 3 shows the process of forming the first wiring layer in a first embodiment of the present invention. [Figure 4] Figure 4 shows the bonding process of the second support in the manufacturing method according to the first embodiment. [Figure 5] Figure 5 shows the peeling step of the first support in the manufacturing method according to the first embodiment. [Figure 6] Figure 6 shows the process of forming through holes by etching in the manufacturing method according to the first embodiment. [Figure 7] Figure 7 shows the process of forming the second wiring layer in the manufacturing method according to the first embodiment. [Figure 8] Figure 8 shows the peeling step of the second support in the manufacturing method according to the first embodiment. [Figure 9] Figure 9 shows the manufacturing method according to the first embodiment after the peeling step of the second support has been performed. [Figure 10] Figure 10 shows the build-up layer formation process in the manufacturing method according to the first embodiment. [Figure 11] Figure 11 is a diagram illustrating the process of forming a connecting pad in the manufacturing method according to the first embodiment. [Figure 12] Figure 12 is a flowchart showing the manufacturing method according to the first embodiment. [Figure 13] Figure 13 is a cross-sectional view of a multilayer wiring board manufactured by the manufacturing method according to the first embodiment. [Figure 14] Figure 14 is a magnified view of the through-electrodes of the multilayer wiring board shown in Figure 13. [Figure 15] Figure 15 shows a multilayer wiring substrate in which a capacitor structure is formed during the first wiring layer formation process. [Figure 16] FIG. 16 is a diagram showing an example where a multilayer wiring board is used as an interposer. [Figure 17] FIG. 17 is a diagram showing a wiring layer forming step in the manufacturing method according to a first modification. [Figure 18] FIG. 18 is a diagram showing a laser-modified portion forming step in the manufacturing method according to the first modification. [Figure 19] FIG. 19 is a flowchart of the manufacturing method according to the first modification. [Figure 20] FIG. 20 is a diagram showing a second support bonding step in the manufacturing method according to a second modification. [Figure 21] FIG. 21 is a diagram showing a laser-modified portion forming step in the manufacturing method according to the second modification. [Figure 22] FIG. 22 is a flowchart of the manufacturing method according to the second modification. [Figure 23] FIG. 23 is a diagram showing a laser absorption layer forming step in the manufacturing method according to a second embodiment. [Figure 24] FIG. 24 is a diagram showing a first support bonding step in the manufacturing method according to the second embodiment. [Figure 25] FIG. 25 is a diagram showing a laser-modified portion forming step in the manufacturing method according to the second embodiment. [Figure 26] FIG. 26 shows a cross-sectional view after wiring formation when a laser absorption layer is applied. [Figure 27] FIG. 27 is a diagram showing a state where the first support has been peeled off. [Figure 28] FIG. 28 is a diagram showing a state where the laser absorption layer has been removed. [Figure 29] FIG. 29 is a flowchart of the manufacturing method according to the second embodiment. [Figure 30] FIG. 30 is a diagram showing a first support peeling step in the manufacturing method according to a third embodiment. [Figure 31] FIG. 31 is a diagram showing bonding methods and evaluation results for Examples 1 to 8 and a comparative example. [Figure 32] Figure 32 shows a diagram illustrating the types of lasers and the materials that have the absorption rates for those laser wavelengths. [Modes for carrying out the invention]

[0010] Embodiments of the present invention will be described below with reference to the drawings. The following description relates to an example of the present invention, and the present invention is not limited thereto. In addition, the same parts are denoted by the same reference numerals in the drawings. The positions, sizes, shapes, and ranges of the components shown in the drawings may not represent their actual positions, sizes, shapes, and ranges in order to facilitate understanding of the invention. Therefore, the present invention is not necessarily limited to the positions, sizes, shapes, and ranges disclosed in the drawings.

[0011] In this disclosure, "surface" may refer not only to the surface of the plate-like member, but also to the interface of a layer contained within the plate-like member that is substantially parallel to the surface of the plate-like member. Furthermore, "upper surface" and "lower surface" refer to the surfaces shown above or below the plate-like member or the layers contained within the plate-like member in the drawing. In addition, "upper surface" and "lower surface" may also be referred to as "first surface" and "second surface."

[0012] Furthermore, "side surface" refers to the surface or thickness of a layer within a plate-like member or a layer contained within a plate-like member. In addition, a part of the surface and the side surface together are sometimes referred to as the "end." Furthermore, "upward" refers to the vertically upward direction when a plate-like member or layer is placed horizontally. In addition, "upward" and its opposite, "downward," may be referred to as the "positive Z-axis direction" and the "negative Z-axis direction," respectively, while the horizontal direction may be referred to as the "X-axis direction" and the "Y-axis direction."

[0013] <First Embodiment> The following describes a method for manufacturing a multilayer wiring layer in a first embodiment of the present invention, with reference to Figures 1 to 11. Through the manufacturing method described here, through holes are formed in the glass substrate 60.

[0014] (Adhesion of the first support) First, the process of bonding the first support 61 to the glass substrate 60 will be explained with reference to Figure 1. Figure 1 is a diagram showing the bonding process of the first support in the manufacturing method according to the first embodiment. Here, a first adhesive layer 62 is formed between the first support 61 and the glass substrate 60, and the second surface 30 of the glass substrate 60 and the first support 61 are bonded via the first adhesive layer 62. In the following explanation, the cross-sectional structure in the thickness direction (z-axis direction) of the glass substrate will be mainly used. The glass substrate has an extension in the horizontal direction (y-axis direction), but for simplicity, it is shown with straight lines as boundaries. The glass substrate 60 has a first surface 20 and a second surface 30 facing the first surface 20. The thickness of the glass substrate 60 is T1. The thickness T1 is, for example, 150 μm or less. As shown here, the first support 61 is bonded to the glass substrate 60 using the first adhesive layer 62 to form a laminated structure 63 consisting of the glass substrate 60, the first adhesive layer 62, and the first support 61.

[0015] The first adhesive layer 62 is formed on at least one of the second surface 30 of the glass substrate 60 or the surface of the first support 61 facing the glass substrate 60, and is composed of a resin composition. This resin composition contains a substance that absorbs the laser used in the through-hole formation process described later. In other words, the resin composition contains an absorbing material having a transmittance of a predetermined value or higher with respect to the wavelength of the laser. The first adhesive layer 62 temporarily fixes the glass substrate 60 and the first support 61, and is used to fix the glass substrate 60 and the first support 61 during a predetermined process.

[0016] A method for forming the first adhesive layer 62 on the first support 61 is, for example, by placing a fluid or non-fluid resin composition on the first support 61 and solidifying it. Methods for applying the resin composition onto the first support 61 include, for example, spray coating, die coating, spin coating, dip coating, roll coating, bar coating, screen printing, and gravure coating. The resin composition used in the first adhesive layer 62 can be solidified using, for example, heat treatment or ultraviolet irradiation treatment.

[0017] The material of the first adhesive layer 62 may include at least one of a curable silicone resin or an acrylic resin that exhibits release properties upon ultraviolet irradiation. For example, when using a curable silicone resin as the material, a resin composition of the curable silicone resin, which includes an organoalkenylpolysiloxane and an organohydrogenpolysiloxane having hydrogen atoms bonded to silicon atoms at the molecular ends, is applied to the first support 61. The resin composition is then solidified by being held in the atmosphere at a temperature of 50°C to 300°C. The resin composition may also contain an organic solvent as needed.

[0018] The above describes a method for forming the first adhesive layer 62 on the first support 61, but the method is not limited to this. Other methods can be appropriately set depending on the material conditions.

[0019] Furthermore, the step of bonding the first support 61 may include a step of placing the first adhesive layer 62 on the first support 61 and then curing the first adhesive layer 62. To bond the first support 61 to the glass substrate 60 via the first adhesive layer 62, methods such as a laminator, a vacuum pressure press, or a reduced pressure bonding machine can be used.

[0020] The material of the first support 61 is preferably the same as that of the glass substrate 60. If the glass substrate 60 is alkali-free glass, it is preferable that the first support 61 is also alkali-free glass. The thickness of the first support can be appropriately set according to the thickness T1 of the glass substrate 60. However, it is preferable that the thickness be such that it can be transported during the manufacturing process, and the range is between 300 μm and 1,500 μm.

[0021] Furthermore, in subsequent processes, when separating the glass substrate 60 from the laminated structure 63, it is necessary to ensure sufficient adhesion between the first support 61 and the first adhesive layer 62 so that delamination does not occur at the interface between the first support 61 and the first adhesive layer 62. Therefore, a surface modification treatment may be performed on the surface of the first support 61 before installing the resin composition. Examples of surface modification treatments include chemical methods that improve the fixing strength chemically, such as using a silane coupling agent (primer treatment), physical methods that increase surface active groups, such as flame treatment, and mechanical treatment methods that produce a wedge effect by increasing the surface roughness, such as sandblasting.

[0022] On the other hand, it is preferable that the first adhesive layer 62 has release properties in order to separate the glass substrate 60 in a subsequent process. If it has release properties, in the process of separating the glass substrate 60 from the laminated structure 63, the glass substrate 60 and the first adhesive layer 62 can be easily separated at their interface.

[0023] (Formation of laser-modified area) Next, with reference to Figure 2, the process of forming the laser-modified portion will be described. Here, a laser is irradiated from the first surface 20 side of the glass substrate 60 to form a laser-modified portion 65 on the glass substrate 60. Figure 2 shows the process of forming a laser-modified portion in the manufacturing method according to the first embodiment. As shown here, a laser is irradiated onto the laminated structure 63 from the first surface 20 side at the position where the through hole will be formed, thereby forming a laser-modified portion 65 that will be the starting point of the through hole. The laser-modified portion 65 extends, for example, perpendicularly to the glass substrate 60 and can be formed at a desired position over almost the entire surface of the glass substrate 60. In this case, the laser-modified portion 65 may be formed to penetrate the glass substrate 60 and reach the first adhesive layer 62 and the first support 61.

[0024] In this case, if a conventional adhesive layer is used for the first adhesive layer 62, laser irradiation may cause cracks to form in the adhesive layer, and when the first support 61 is peeled off from the glass substrate 60, the adhesive resin may remain on the glass substrate 60 as residue. If such adhesive resin remains on the glass substrate 60, it may cause problems in the subsequent through-hole formation process by hydrofluoric acid etching. For example, it may lead to the occurrence of surface irregularities on the glass substrate 60. In contrast, the resin composition used in the first embodiment absorbs the laser power within the resin when irradiated with a laser. As a result, no cracks occur within the first adhesive layer 62, and no adhesive resin remains on the glass substrate 60 when the first support 61 is peeled off from the glass substrate 60.

[0025] (Formation of the first wiring layer) Next, the process of forming the first wiring layer 21 will be described with reference to Figure 3. Figure 3 is a diagram showing the process of forming the first wiring layer in a first embodiment of the present invention. As shown here, a first wiring layer 21 including a conductive layer and an insulating resin layer is formed on the first surface 20 on the glass substrate 60 of the laminated structure 63.

[0026] In the process of forming the first wiring layer 21, first, a seed layer including a hydrofluoric acid-resistant metal layer 15 is formed on the glass substrate 60. The hydrofluoric acid-resistant metal layer 15 on the glass substrate 60 is an alloy layer containing at least one of chromium or nickel, and is formed to a thickness of 10 nm to 1,000 nm by sputtering. Subsequently, a conductive metal film is formed on the hydrofluoric acid-resistant metal layer 15 to a desired thickness. As the material for the conductive metal film, at least one can be appropriately selected from, for example, Cu, Ni, Al, Ti, Cr, Mo, W, Ta, Au, Ir, Ru, Pd, Pt, AlSi, AlSiCu, AlCu, NiFe, ITO, IZO, AZO, ZnO, PZT, TiN, and Cu3N4.

[0027] Next, the through-electrode connection portion (electrode) and wiring are formed, for example, by the semi-additive (SAP) method. In the semi-additive method, a photoresist is used to form the desired pattern. Generally, a dry film resist is used, but a liquid resist may also be used. After exposing and developing the resist to form the desired pattern, a plating film with a thickness of 2 μm to 20 μm is formed by electroplating. By peeling off the unnecessary resist pattern and etching the seed layer, the wiring 16 located between the through-electrode connection portion 41, which is located above the laser-modified portion 65, and the laser-modified portion 65 is formed.

[0028] Finally, an insulating resin layer 25 is formed. The insulating resin layer 25 is a material containing at least one of epoxy resins, polyimide resins, or polyamide resins, and containing fillers such as silica, titanium oxide, or urethane. It is preferably a liquid or film material. In the case of liquid resins, it can be formed by spin coating, and in the case of film resins, it can be formed by heating and pressurizing under vacuum using a vacuum laminator. The material of the insulating resin layer 25 can be appropriately selected as needed.

[0029] In this example, we have shown how to form a through-electrode connection portion 41 and wiring 16 within the first wiring layer 21, but it is also possible to form other circuit elements, such as capacitors and inductors.

[0030] (Adhesion of the second support) Next, the bonding process for the second support will be described with reference to Figure 4. Figure 4 is a diagram showing the bonding process for the second support in the manufacturing method according to the first embodiment. As shown here, a second adhesive layer 71 is formed on the first wiring layer 21 of the laminated structure 63, and the second support 70 is bonded to the second adhesive layer 71.

[0031] The second adhesive layer 71 can be appropriately selected from a resin that can be peeled off by absorbing light such as UV light, causing heat generation, sublimation, or alteration; a resin that can be peeled off by foaming due to heat; or functional groups that temporarily fix the glass substrate 60 and the first support 61.

[0032] The second support 70 is preferably made of the same material as the glass substrate 60. If the glass substrate 60 is alkali-free glass, the first support 61 is also preferably alkali-free glass. The thickness of the second support 70 can be set appropriately according to the thickness of the glass substrate 60. However, it is preferable that the thickness be transportable, and is in the range of 300 μm to 1,500 μm.

[0033] (Peeling of the first support) Next, the separation process of the first support will be described with reference to Figure 5. Figure 5 is a diagram showing the peeling process of the first support 61 in the manufacturing method according to the first embodiment. As shown here, the first support 61 is peeled off from the glass substrate 60.

[0034] In peeling the first support 61 from the glass substrate 60, a peeling initiation point is physically formed at the interface between the glass substrate 60 and the first support 61 from the side surface of the laminated structure 63, and the peeling can be advanced by applying force to this peeling initiation point. Scribes are formed at the interface between the glass substrate 60 and the first support 61, and a force is applied to the glass substrate 60 and the first support 61 in a peeling direction. More specifically, the area where the first support 61 and the first support 61 have been marked with a cutter or the like is designated as the peeling starting point, and by applying a force in a direction that pulls the first support 61 and the glass substrate 60 apart (in the positive z-axis direction and the -z-axis direction), the glass substrate 60 and the first support 61 can be separated. By applying a force to separate the first support 61 from the glass substrate while performing the scribing process, the peeling process can be carried out smoothly.

[0035] (Formation of through-holes by etching) Next, the process of forming through holes by etching will be described with reference to Figure 6. Figure 6 is a diagram showing the process of forming through holes by etching in the manufacturing method according to the first embodiment. As shown here, the through holes are formed by etching from the second surface 30 side of the glass substrate 60. The laser-modified portion 65 is selectively etched. This forms the through holes 11. Wet etching using an aqueous hydrofluoric acid solution is suitable for etching. The amount of etching with the aqueous hydrofluoric acid solution is set appropriately according to the thickness of the glass multilayer wiring substrate. For example, if the thickness T1 of the glass substrate 60 is 200 μm, it is desirable that the etching amount be in the range of 50 μm to 175 μm. Furthermore, the glass substrate 60 is etched in the same way as the laser-modified portion 65. The thickness T2 of the glass substrate 60 after etching is preferably in the range of 25 μm to 150 μm.

[0036] (Formation of the second wiring layer) Next, the process for forming the second wiring layer will be described with reference to Figure 7. Figure 7 is a diagram showing the process for forming the second wiring layer in the manufacturing method according to the first embodiment. As shown here, the second wiring layer is formed on the second surface of the glass substrate 60 from which the first support 61 has been peeled off. The second wiring layer 22 includes a through-electrode connection portion 42 and an insulating resin layer 25. The through-electrode connection portion 42 is formed by forming a seed layer for power supply, forming a pattern with resist, plating to form a plating with a thickness of 2 μm to 20 μm, then peeling off the unnecessary resist pattern and removing the seed layer. The through-electrode 12 in the glass substrate 60 is also formed through the same process as the through-electrode connection portion 42. After the through-electrode connection portion 42 and the through-electrode 12 are formed, an insulating resin layer 25 is formed. The resin forming the insulating resin layer 25 is also filled inside the through-electrode 12. In this example, the insulating resin layers 25 formed on the first wiring layer 21 and the second wiring layer 22 are assumed to be made of the same material, but this is not limited to this. Different materials may be used to form the insulating resin layers.

[0037] In the second wiring layer 22, since there is no etching treatment with hydrofluoric acid aqueous solution in subsequent processes, a material different from the hydrofluoric acid-resistant metal can be used. In this case, a metal layer made of a material different from the hydrofluoric acid-resistant metal is formed on the side surface of the through hole 11, forming the through electrode connection portion 42. Examples of materials different from the hydrofluoric acid-resistant metal include Ti and Cu, and at least one metal layer made of these materials is formed on the side surface of the through hole 11 and on the second surface 30 of the glass substrate 60. The materials, number of layers, etc., are not limited to those disclosed in this embodiment, but can be set as appropriate as needed.

[0038] (Detachment of the second support) Next, the peeling process of the second support 70 will be described with reference to Figures 8 and 9. Figure 8 is a diagram showing the peeling process of the second support 70 in the manufacturing method according to the first embodiment. Figure 9 is a diagram showing the state after the peeling process of the second support 70 has been performed in the manufacturing method according to the first embodiment. As shown in Figure 8, the second support 70 is peeled off from the glass substrate 60. More specifically, the second adhesive layer 71 formed above the first wiring layer 21 on the first surface 20 side of the glass substrate 60 and the second support 70 are peeled off from the interface between the first wiring layer 21 and the second adhesive layer 71 on the first surface side. As a result, as shown in Figure 9, a glass substrate 60 is obtained in which the first wiring layer 21 is formed on the first surface 20 side and the second wiring layer 22 is formed on the second surface 30 side of the glass substrate 60. When peeling the second support 70 from the second wiring layer 22, a peeling method can be appropriately selected from UV light irradiation, heat treatment, physical peeling, etc., depending on the material used for the second adhesive layer 71. In addition, if adhesive resin residue is generated at the joint surface between the first wiring layer 21 and the second adhesive layer 71, plasma cleaning, ultrasonic cleaning, water washing, solvent cleaning using alcohol, etc. may be performed.

[0039] (Formation of the build-up layer) Next, with reference to Figure 10, the process for forming the build-up layer, in other words, the stacked wiring layer of the first wiring layer 21 and the second wiring layer 22, will be described. Figure 10 is a diagram showing the process for forming the build-up layer in the manufacturing method according to the first embodiment. As shown in Figure 10, a conductive electrode 31 for conductivity is formed in the first wiring layer 21, and a conductive electrode 32 for conductivity is formed in the second wiring layer. The conductive electrodes 31 and 32 are formed by first forming vias in the insulating resin layer 25 with a laser, then forming a seed layer on the vias, and then using a semi-additive process (i.e., resist pattern formation, plating, resist stripping, seed layer removal, insulating resin layer 25, and a series of other processes). The first wiring layer 21 and the second wiring layer 22 are stacked in layers of at least one, and the number of layers can be set as appropriate as needed. In Figure 10, both the first wiring layer 21 and the second wiring layer 22 are stacked in layers of two.

[0040] The laser used to form the conductive electrodes 31 and 32 is different from the laser used to form the laser-modified portion 65. For example, it is preferable to use a pulsed laser such as a carbon dioxide laser or a UV-YAG laser, and a laser with a pulse width on the order of μs is suitable.

[0041] (Formation of connection pads) Next, the formation of the connection pads will be described with reference to Figure 11. Figure 11 is a diagram illustrating the process of forming the connection pads in the manufacturing method according to the first embodiment. As shown here, after forming an outer protective film such as solder resist 55 on the first wiring layer 21 and the second wiring layer 22, a bonding pad 51 for semiconductor devices is formed on the first wiring layer 21, and a bonding pad 53 for the substrate is formed on the second wiring layer 22. Surface treatments such as Ni / Au, Ni / Pd / Au, IT, OSP (water-soluble preflux) are applied to the bonding pad 51 for semiconductor devices and the bonding pad 53 for the substrate, and if necessary, solder for bonding semiconductor devices 52 and solder for bonding substrates 54 are formed to complete the multilayer wiring substrate. Note that Ni / Au means that both Ni and Au are used, and Ni / Pd / Au means that any of Ni, Pd, and Au are used.

[0042] (Flowchart of the manufacturing method according to the first embodiment) The process described above is summarized in a flowchart. Figure 12 is a flowchart of the manufacturing method according to the first embodiment.

[0043] Step S1 is the bonding process of the first support. The first support 61 is bonded to the glass substrate 60. The glass substrate 60 and the first support 61 are connected via a first adhesive layer 62 made of a resin composition. Step S2 is the process of forming a laser-modified layer. The laser is irradiated from the side opposite to the side to which the first support is bonded. The laser-modified area becomes the starting point of the through hole. Step S3 is the process of forming the first wiring layer. The first wiring layer is formed with a through electrode connection portion 41 and wiring 16. Step S4 is the bonding process of the second support. The second support 70 is bonded onto the first wiring layer 21 via the second adhesive layer 71. Step S5 is the peeling step of the first support. The first support 61 is separated from the glass substrate 60. Step S6 is a process for forming through holes by etching. The laser-modified portion 65 is selectively etched to form through holes 11. Step S7 is the process of forming the second wiring layer. The second wiring layer 22 includes a through electrode connection portion 42 and an insulating resin layer 25. Step S8 is the peeling process of the second support. The second support 70 is separated from the glass substrate 60. Step S9 is the formation of the build-up layer. A wiring layer is formed on the first wiring layer 21 and the second wiring layer 22. Step S10 is the formation of connection pads. A protective film is formed on the surfaces of the first wiring layer 21 and the second wiring layer 22, and solder bumps are formed for bonding with semiconductor elements and substrates.

[0044] <Effects and Actions> As described above in the first embodiment, the manufacturing method involves first bonding the glass substrate 60 to the first support 61, followed by a series of manufacturing steps including the laser modification process. Even if the thickness of the glass substrate is 150 μm or less, it can be easily handled because of the first support 61, and the glass substrate 60 can be easily handled even in the laser modification process (step S2) which requires precision. As a result, there is no need to impose a limit on the thickness of the glass substrate, and a thinner glass substrate can be used, making it possible to manufacture even thinner multilayer wiring boards.

[0045] Furthermore, regarding the laser modification process, conventionally, only the glass substrate 60 was targeted for laser irradiation. As a result, the laser modification was not always uniformly formed near the surface of the glass substrate, leading to variations in the shape of the through-holes. On the other hand, in the first embodiment, the laser is irradiated from the first surface 20 side of the glass substrate 60, and not only the glass substrate 60 is targeted for laser irradiation, but the first support 61, which is made of the same material as the glass substrate 60, is also targeted for irradiation. Since the laser's focal point is set in the first support 61, the laser-modified portion 65 can be reliably formed over the thickness direction (z-axis direction) of the glass substrate 60. Although there are parts of the first support 61 that are not sufficiently irradiated with the laser, these parts are peeled off and removed together with the first support 61 in the peeling process of the first support (step S5). As a result, the laser-modified portion 65 formed on the glass substrate 60 is highly homogeneous and formed with high precision, making it possible to uniformly form through holes even after subsequent etching. Furthermore, when forming the laser-modified portion on the glass substrate 60, it is sufficient to set the laser focus to be greater than or equal to the thickness of the glass substrate 60, and the laser irradiation position can be set regardless of the structure formed on the first surface 20 and the second surface 30 of the glass substrate 60. Therefore, it is expected that the degree of freedom in setting the laser irradiation conditions can be increased. Thus, according to the manufacturing method of the first embodiment, it is possible to manufacture a multilayer wiring board having through holes with little variation.

[0046] <Regarding a glass multilayer wiring board according to an embodiment of the present invention> The structure of a multilayer wiring board manufactured by the manufacturing method according to the first embodiment will be described with reference to Figures 13 to 15. Figure 13 is a cross-sectional view of a multilayer wiring board manufactured by the manufacturing method according to the first embodiment. Figure 13 is the same as the multilayer wiring board shown in Figure 11. Figure 14 is an enlarged view of the through-electrode 12 of the multilayer wiring board shown in Figure 13. Figure 15 is a view of a multilayer wiring board when a capacitor structure is formed in the first wiring layer formation process.

[0047] Here, the dielectric layer 80 shown in Figure 15 can be manufactured as part of the first wiring layer formation process. The through-electrode connection portion 41, the dielectric layer 80, and the conductive electrode 31 formed in the positive z-axis direction of the dielectric layer 80 are combined to form the MIM structure.

[0048] <Effects and Actions> In conventional technology, where a glass core substrate and a glass support are bonded together using an adhesive, and a laser modification process is performed, it is thought that the modification occurs due to the heat generated by the laser irradiation when the adhesive is irradiated with the laser. Consequently, during the delamination of the glass support, cohesive failure occurs within the adhesive bulk, starting from the modified portion of the adhesive, resulting in residue generation on the core glass side. If hydrofluoric acid etching is performed with this residue present, etching variations occur, leading to unevenness on the core substrate surface. These unevennesses on the core substrate surface contribute to poor adhesion during subsequent film formation processes, variations in through-hole diameters, and deterioration of characteristic values ​​when used in multilayer wiring boards.

[0049] On the other hand, in the first embodiment, the first adhesive layer 62 contained a substance that absorbs lasers in the resin composition, so that modification during laser irradiation is suppressed and cohesive failure can be prevented. As a result, it is possible to manufacture a multilayer wiring board that can form through holes with less variation.

[0050] Furthermore, the above-described manufacturing method makes it possible to form through holes with minimal variation, allowing for stable formation of the opening diameter D2 of the second wiring layer 22 and preventing problems such as the opening diameter D2 being blocked. As a result, as shown in Figure 14, the relationship between the opening diameter D1 of the first wiring layer 21 and the opening diameter D2 of the second wiring layer 22 is D2 > D1, and a through electrode 12 can be formed in which the opening diameter D1 on the first surface 20 side / opening D2 on the second surface side is in the range of approximately 0.3 to 0.8. With such a through electrode 12, the seed layer adheres to the sides and bottom surfaces of the through electrode 12. This ensures adhesion of the metal film to the sides and bottom surfaces of the through electrode 12, thereby obtaining high bonding reliability.

[0051] (Usage example) The manufacturing method for glass multilayer wiring boards using thin glass with a thickness of 150 μm or less, as described above, can be used for devices such as glass multilayer wiring boards for passive components incorporating a capacitor structure as shown in Figure 15, and interposers equipped with multiple semiconductor elements as shown in Figure 16. Figure 15 shows a multilayer wiring board for passive components with a built-in capacitor structure. The dielectric layer 80 shown in Figure 15 can be manufactured as part of the first wiring layer formation process. The through-electrode connection portion 41, the dielectric layer 80, and the conductive electrode 31 formed in the positive z-axis direction of the dielectric layer 80 are combined to form a MIM structure, which is a capacitor structure. Figure 16 shows an example in which the multilayer wiring board is used as an interposer. The multilayer wiring board 1 connects the semiconductor element 100 and the BGA (ball grid array) substrate 90.

[0052] Figures 15 and 16 show an example, and the applications are not limited thereto. The manufacturing method according to the first embodiment facilitates the use of thin glass with a thickness of 150 μm or less, and makes it possible to easily form through holes and through electrodes. The manufactured multilayer wiring board can be used in various devices.

[0053] <Modified form of the first embodiment> The manufacturing method in the first embodiment is shown in the flowchart in Figure 10, but the order of the steps is not limited thereto. For example, the order of the steps can also be as shown in the following modified example 1 or modified example 2. In the following description, the same or equivalent components as in the first embodiment are denoted by the same reference numerals, and their descriptions are simplified or omitted.

[0054] <First variation> Next, a first modified example of the first embodiment will be described with reference to Figures 17 to 19. The first modified example differs from the first embodiment in that the laser modification process is performed after the first wiring layer formation process.

[0055] (Formation of the first wiring layer) Figure 17 shows the wiring layer formation process in the manufacturing method according to the first modified example. In the first modified example, as shown in Figure 17, following the bonding process of the first support 61, the first wiring layer 21 is formed on the glass substrate 60.

[0056] In the process of forming the first wiring layer 21, first, a seed layer containing a hydrofluoric acid-resistant metal layer 15 is formed on the glass substrate 60. Next, the through-electrode connection portion 41 and the wiring 16 between the through-electrodes are formed using the semi-additive (SAP) method, and the unnecessary seed layer is removed. Finally, the insulating resin layer 25 is formed. The materials and deposition methods for the hydrofluoric acid-resistant metal layer and electrodes are the same as in the first embodiment.

[0057] (Formation of laser-modified area) Next, with reference to Figure 18, the process of forming the laser-modified portion in the first modified example will be described. Figure 18 is a diagram showing the process of forming the laser-modified portion in the manufacturing method according to the first modified example. As shown here, a laser is irradiated onto the laminated structure 63 from the first support 61 side to form the laser-modified portion 65. The focus and intensity are adjusted so that the laser-modified portion 65 is formed uniformly in the thickness direction of the glass substrate 60.

[0058] (Other processes) Figure 19 is a flowchart showing the manufacturing method according to the first modified example. In the first modified example, the manufacturing method is the same as that according to the first embodiment, except for the formation of the first wiring layer (step S12) and the formation of the laser modified section (step S13).

[0059] <Second variation> Next, a second modified example of the first embodiment will be described with reference to Figures 20 to 22. The second modified example differs from the first embodiment in that the laser modification process is performed after the first wiring layer formation process and the second support bonding process.

[0060] (Adhesion of the second support) Figure 20 shows the bonding process of the second support in the manufacturing method according to the second modified example. In the second modified example, as shown in Figure 20, the second support 70 is bonded to the laminated structure 63 while the glass substrate 60 and the first support 61 are not laser modified.

[0061] (Formation of laser-modified area) Figure 21 shows the process of forming the laser-modified portion in the manufacturing method according to the second modified example. As shown here, the laminated structure 63 is irradiated with a laser from the first support 61 side to form the laser-modified portion 65.

[0062] (Other processes) Figure 22 is a flowchart showing the manufacturing method according to the second modified example. In the second modified example, the manufacturing method is the same as according to the first embodiment, except that the order of forming the laser-modified section (step S22) is different.

[0063] (Effects / Actions) Even if a problem occurs in the manufacturing process and it becomes impossible to proceed with the manufacturing process as is, the manufacturing process can be flexibly modified as shown in the first and second modified examples, allowing the manufacturing process to continue.

[0064] <Second Embodiment> The second embodiment differs from the first embodiment in that a laser absorption layer is provided adjacent to the first adhesive layer. In the following description, components that are the same as or equivalent to those in the first embodiment are denoted by the same reference numerals, and their descriptions are simplified or omitted.

[0065] (Adhesion of the first support) Referring to Figures 23 and 24, the bonding step of the first support in the manufacturing method according to the second embodiment will be described. Figure 23 is a diagram showing the laser absorption layer formation step in the manufacturing method according to the second embodiment. Figure 24 is a diagram showing the bonding step of the first support in the manufacturing method according to the second embodiment.

[0066] As shown in Figure 23, a laser absorption layer 64 is formed on the second surface 30 of the glass substrate 60. A metal film that absorbs lasers can be used as the laser absorption layer 64. For example, if a YAG laser (wavelength 1064 nm) is used in the laser modification process, an aluminum film capable of absorbing a wavelength of 1064 nm is deposited by vapor deposition. However, it is not limited to aluminum; other metal films with an absorption rate corresponding to the laser wavelength may also be used.

[0067] Furthermore, a resin material can also be used for the laser absorption layer 64. When using a resin material, it is conceivable to use a resin material in which a laser-absorbing material is dispersed. When forming the resin material as the laser absorption layer 64 on the glass substrate 60, it is possible to use the same method as the method for forming the first adhesive layer 62 on the first support 61 shown in the first embodiment.

[0068] Figure 24 shows the process of bonding the glass substrate 60 and the first support 61. As shown here, the glass substrate 60, laser absorption layer 64, first adhesive layer 62, and first support 61 are stacked in that order from top to bottom to form a laminated structure 63. Thus, in the second embodiment, the laser absorption layer 64 and the first adhesive layer 62 function as adhesive layers for bonding the glass substrate 60 and the laser absorption layer 64. Such adhesive layers are not limited to just the two layers of the laser absorption layer 64 and the first adhesive layer 62, but may include other layers.

[0069] (Formation of laser-modified area) Next, the process of forming the laser-modified portion will be described with reference to Figure 25. Figure 25 is a diagram showing the process of forming the laser-modified portion in the manufacturing method according to the second embodiment. As shown here, a laser is irradiated onto the laminated structure 63 from the first surface 20 side of the glass substrate 60 to form the laser-modified portion 65. At this time, the laser-modified portion 65 is formed uniformly in the thickness direction from the first surface 20 to the second surface 30 of the glass substrate 60. On the other hand, since the laser energy is absorbed by the laser absorption layer 64, the laser-modified portion 65 is not formed on the first adhesive layer 62 and the first support 61.

[0070] By placing the laser absorption layer 64 between the first adhesive layer 62 and the glass substrate 60, the laser cannot reach the first adhesive layer 62, thereby preventing deterioration of the first adhesive layer 62. As a result, cracks do not occur within the first adhesive layer 62, and cohesive failure does not occur in the first adhesive layer 62 when the first support 61 is peeled off from the glass substrate 60. Furthermore, since the first adhesive layer 62 and the glass substrate 60 do not come into contact, even if cohesive failure occurs in the first adhesive layer 62 during the process of separating the first support 61 from the glass substrate 60, it is possible to prevent adhesive resin from remaining on the glass substrate 60.

[0071] (Peeling of the first support) Next, the peeling process of the first support will be described with reference to Figures 26 to 28. Figure 26 shows a cross-sectional view after wiring formation when the laser absorption layer 64 is applied. As shown here, a first wiring layer 21 is formed consisting of a hydrofluoric acid-resistant metal layer 15, a through-electrode connection portion 41, wiring 16, and an insulating resin layer 25. A second adhesive layer 71 is formed above the first wiring layer 21, and the second support 70 is bonded to the second adhesive layer 71.

[0072] Figure 27 shows the state after the first support 61 has been peeled off. In peeling the first support 61 from the glass substrate 60, a peeling initiation point is physically formed at the interface between the glass substrate 60 and the first support 61, and the peeling is advanced by applying force to this peeling initiation point. More specifically, the interface between the glass substrate 60 and the first support 61 is marked with a cutter or the like to create a delamination area. The glass substrate 60 and the first support 61 are separated by pulling them in the direction of delamination. By applying a scribing process while the first support 61 and the glass substrate are being pulled apart, the peeling process can be carried out smoothly.

[0073] After peeling off the first support 61 and the first adhesive layer 62, the laser absorption layer 64 remains on the glass substrate 60. The first adhesive layer 62 also remains on the first support. For example, ITO is used as the material for the laser absorption layer 64. ITO can be removed with a common dissolving solution. Furthermore, even if the laser absorption layer 64 is composed of a material other than ITO, it can be removed by using an etching solution suitable for each material or by using dry etching. Figure 28 shows the state after the laser absorption layer 64 has been removed. This is the same state as in Figure 5 of the first embodiment. The subsequent steps are the same as those for through-hole formation by etching in the first embodiment and are therefore omitted.

[0074] Figure 29 is a flowchart illustrating the manufacturing method of the second embodiment. In step S101, the laser absorption layer 64 is formed. The laser absorption layer 64 is selected to match the wavelength of the laser used in the laser modification process on the glass substrate 60. In step S102, the laser absorption layer 64 is removed. The laser absorption layer is removed from the glass substrate 60 by means of etching or other selected methods. The other steps are the same as those in the manufacturing method according to the first embodiment.

[0075] <Effects and Actions> In the second embodiment, a laser-absorbing layer is provided between the glass substrate 60 and the first adhesive layer 62. This allows the laser irradiated when forming the laser-modified portion to be absorbed or its intensity to be weakened. As a result, the laser energy reaching the first adhesive layer during the laser-modified portion formation process can be weakened, and alteration of the first adhesive layer can be avoided.

[0076] Thus, in the manufacturing method according to the second embodiment, it is possible to prevent the generation of adhesive resin residue on the glass substrate 60, thereby reducing variations in through-holes and preventing defects caused by unevenness on the surface of the glass substrate.

[0077] <Third Embodiment> This section describes the case where polyimide is used as the first adhesive layer 62 for bonding the glass substrate 60 and the first support 61. Polyimide has higher heat resistance than other organic materials and polymer materials, and is also a material that has excellent mechanical properties and resistance to chemicals. Furthermore, since polyimide absorbs in the UV wavelength band, when it is formed on a transparent material such as alkali-free glass and irradiated with a laser with a UV wavelength, the laser that passes through the alkali-free glass is absorbed at the polyimide interface, ablation occurs, and delamination at the glass-polyimide interface is possible.

[0078] (Peeling of the first support) Next, the peeling process of the first support will be described with reference to Figure 30. Figure 30 is a diagram showing the peeling process of the first support in the manufacturing method according to the third embodiment.

[0079] Prior to the process shown in Figure 30, a first support bonding process is performed. In the first support bonding process, a first adhesive layer 62 made of polyimide is formed on the glass substrate 60.

[0080] The polyimide is formed by coating it onto the glass substrate 60 using a spin coater. As for the coating method, the method used in the bonding step of the first support in the first embodiment, where the first adhesive layer is coated onto the first support 61, can be applied to the relationship between the glass substrate 60 and the polyimide. Furthermore, the polyimide applied to the first support 61 is bonded to the glass substrate 60 using a press machine, and curing is performed to ensure a stronger bond, thereby preventing delamination during subsequent processes.

[0081] As shown in Figure 30, in the first support peeling step, the first support 61 is peeled off from the glass substrate 60. A laser lift-off method is used for peeling. The condition for this is that the laser has a laser absorption wavelength for polyimide. In the third embodiment, a UV laser was used. The polyimide remaining on the second surface of the glass substrate 60 can be removed using a solvent, and after removal, no polyimide remains on the glass substrate 60. Furthermore, even if materials other than polyimide are used, they can be removed using a solvent suitable for each material or by dry etching.

[0082] The manufacturing method is the same as that according to the first embodiment, except that polyimide is used for the first adhesive layer 62.

[0083] (Effects / Actions) In this embodiment, by using a material that absorbs the laser wavelength used for delamination in the first adhesive layer, even if cracks occur within the first adhesive layer 62, delamination does not occur by pulling the first support 61 and the glass substrate apart. As a result, cohesive failure does not occur within the first adhesive layer, and no adhesive resin remains on the glass substrate 60. Thus, in the manufacturing method according to the third embodiment, it is possible to prevent the generation of adhesive resin residue on the glass substrate 60, thereby reducing variations in through-holes and preventing defects caused by unevenness on the surface of the glass substrate.

[0084] In this invention, polyimide was used to ensure heat resistance in subsequent processes, but other resins or inorganic films can be used as long as they absorb the laser wavelength used for delamination and are suitable for ablation. The laser wavelength may also be changed to suit the material.

[0085] (Examples) An example of applying the present invention is shown below.

[0086] <Examples> Examples of applications of the present invention are described below. A picosecond laser with a wavelength of 1064 nm was used in the process of forming the laser-modified section. Therefore, since the glass substrate 60, the first adhesive layer 62, and the first support 61 will be irradiated with a laser with a wavelength of 1064 nm, it is necessary to select materials that absorb energy in the near-infrared region in order to absorb the energy. Materials that make up the infrared absorption layer include, for example, ITO (indium tin oxide) nanoparticles, ATO (antimony tin oxide) nanoparticles, LaB6 (lanthanum hexaboride), CWO (tungsten cesium oxide) nanoparticles, cyanine dyes, phthalocyanine dyes, naphthalocyanine compounds, nickel dithiolene complexes, squarium dyes, quinone compounds, diinmonium compounds, and azo compounds as infrared absorbers.

[0087] (Example 1) Example 1 is an example where the manufacturing method of the first embodiment is applied. Alkali-free glass (NEG OA-10G) was prepared as the first support 61. The surface of the first support 61 was thoroughly cleaned with pure water, alkali, etc. The bonding process for the first support will now be described. Next, as the first adhesive layer 62, a resin composition was used as the material, which consisted of the following elements: 100 parts by weight of silicone adhesive was used as the basis. • Silicone adhesive ("KR-3704", manufactured by Shin-Etsu Chemical Co., Ltd.) 100 parts by weight • Platinum catalyst ("CAT-PL-50T", manufactured by Shin-Etsu Chemical Co., Ltd.) 1 part by weight 150 units of toluene • Near-infrared absorbing material ("ITO nanoparticle toluene dispersion 10 wt%", manufactured by AS ONE) 10 parts by weight • Silane coupling agent ("KBM-603", manufactured by Shin-Etsu Chemical Co., Ltd.) 0.2 parts by weight The above resin composition was applied to the first support 61, heated in air at 140°C for 3 minutes, and then heat-cured in air at 230°C for 20 minutes to obtain a 10 μm thick cured silicone film on the first support 61. Next, the glass substrate 60 was placed on the first adhesive layer 62 formed on the first support 61, and bonding was performed by vacuum pressing. Since ITO nanoparticles act as inorganic fillers and mixing them may reduce their adhesion to the glass, a silane coupling agent was added to compensate for this. Adhesion must be maintained throughout the subsequent wiring formation and delamination processes, and easy to remove during the support delamination process. Therefore, the adhesion strength was set to 0.15 J / mm². 2More than 0.45j / mm 2 The adjustments were made to fit within the following range.

[0088] (Example 2) Example 2 differs from Example 1 in that the near-infrared absorbing material is 1 part by weight. Otherwise, it is the same as Example 1.

[0089] (Example 3) Example 3 differs from Example 1 in that it contains 5 parts by weight of the near-infrared absorbing material. Otherwise, it is the same as Example 1.

[0090] (Example 4) Example 4 differs from Example 1 in that it contains 20 parts by weight of near-infrared absorbing material. Otherwise, it is the same as Example 1.

[0091] (Comparative example) The comparative example used a resin composition prepared by dissolving 100 parts by weight of silicone adhesive and 1 part by weight of platinum catalyst in 150 parts by weight of toluene. This differs from Examples 1 to 4 in that it does not contain a near-infrared absorbing material. The steps other than the bonding step of the first support were the same as those in the manufacturing method of the first embodiment.

[0092] (Example 5) Example 5 is an example where the manufacturing method of the second embodiment is applied. The bonding process for the first support will now be described. An ITO film was deposited on the second surface of the glass substrate 60 as a laser absorption layer 64 by sputtering. The thickness of the ITO film was set to 1000 nm. The same resin composition used in the comparative example was used as the first adhesive layer 62. The glass substrate 60, ITO film, first adhesive layer, and first support substrate were stacked in that order, and bonding was performed by vacuum pressing.

[0093] (Example 6) Example 6 differs from Example 5 in that the thickness of the ITO film was set to 500 nm. Otherwise, it is the same as Example 5.

[0094] (Example 7) Example 7 differs from Example 5 in that the thickness of the ITO film was set to 2000 nm. Otherwise, it is the same as Example 5.

[0095] (Regarding the peeling process of the first support in Examples 5 to 7) In Examples 5 to 7, after the peeling step of the first support, adhesive resin of the laser absorption layer 64 remained on the glass substrate 60. Therefore, the glass substrate 60 was immersed in the following dissolving solution to remove the residue. • ITO etching solution ("ITO-301", manufactured by Kanto Chemical Co., Ltd.)

[0096] (Example 8) Example 8 shows the case where the manufacturing method of the third embodiment is applied. Alkali-free glass (NEG OA-10G) was prepared as the first support 61. The surface of the first support was thoroughly cleaned with pure water, alkali, etc. For the bonding process of the first support, a resin composition containing the following polyimide was used as the first adhesive layer 62. • Polyimide ("PIAD600", manufactured by Arakawa Chemical Industries, Ltd.) 90 parts by weight Epoxy resin ("TETRAD-X", manufactured by Mitsubishi Gas Chemical Company) 10 parts by weight • Silane coupling agent ("KBM-603", manufactured by Shin-Etsu Chemical Co., Ltd.) 0.2 parts by weight • Toluene 100 copies The above resin composition was applied to a glass substrate 60 and heated in air at 150°C for 5 minutes to form a first adhesive layer. Then, the glass substrate 60, the first adhesive layer, and the first support were stacked in that order and bonded together by vacuum pressing. After bonding, the first adhesive layer was cured by heating in air at 180°C for 1 hour.

[0097] (Regarding the peeling process of the first support in Example 8) In Example 8, after the peeling step of the first support, adhesive resin of the first adhesive layer 62 remained on the glass substrate 60. Therefore, the glass substrate 60 was immersed in the following dissolving solution to remove the residue. • Etching solution ("eSolve 21KZE-100", manufactured by Kaneko Chemical Co., Ltd.)

[0098] (Evaluation details) For Examples 1 to 8 and the Comparative Example, the laminated structure 63 formed from the first support 61, first adhesive layer 62, and glass substrate 60 bonded by each method was subjected to subsequent steps up to the step of peeling off the first support 61. Figure 31 shows the bonding method and evaluation results for Examples 1 to 8 and the Comparative Example. Here, the delamination interface is an indicator of XX. Furthermore, the feasibility of peeling indicates whether the glass substrate 60 can be peeled off without damaging it. The symbol "〇" indicates that peeling was possible without damage. For all samples, peeling was successful. Furthermore, the presence or absence of residue was determined by examining the first surface 20 of the glass substrate 60 with an optical microscope or the like. The symbol "〇" indicates that no residue remains. The symbol "△" indicates that residue was sometimes present and sometimes absent. The symbol "×" indicates that residue is always present. While residue was always present in the comparative examples, it has been shown that the residue can be eliminated in Examples 1 through 8.

[0099] As described above, in the manufacturing methods of the first to third embodiments, conditions were confirmed under which no residue remains on the glass substrate during the peeling process of the first support. Therefore, by applying the first to third embodiments, it is possible to prevent the occurrence of defects caused by the glass surface condition when manufacturing multilayer wiring boards.

[0100] Figure 32 shows the types of lasers and the materials that have the absorption rate of those laser wavelengths. CO2 lasers have a wavelength of approximately 1000 nm, and polyimide or SiN can be used as the absorption material. YAG lasers have a wavelength of 1064 nm, and ITO, Fe, Ti, LaB6 (lanthanum hexaboride), and Mo are suitable materials, with CWO (cesium-doped tungsten oxide) from Mitsui Mining & Smelting Co., Ltd. being a suitable commercially available product. By selecting a material that meets the manufacturing conditions from these materials, the bonding process of the first support in the first to third embodiments can be performed.

[0101] <Other Inventions> This disclosure also encompasses the following inventions: (Invention 1) In a method for manufacturing a multilayer wiring substrate having a first surface and a second surface, in which through holes are formed in the glass substrate, A bonding step in which an adhesive layer is formed on a first support used when transporting the glass substrate, and the second surface of the glass substrate and the first support are bonded together via the adhesive layer, A modification portion formation step involves irradiating the glass substrate with a laser from the first surface side to form a laser-modified portion on the glass substrate, A first support peeling step of peeling the first support from the glass substrate, The process includes a through-hole forming step in which an etching process is performed from the first surface side of the glass substrate to form through-holes, A method for manufacturing a multilayer wiring substrate, characterized in that the adhesive layer contains an absorbing material having a transmittance of a predetermined value or higher with respect to the wavelength of the laser. (Invention 2) A method for manufacturing a multilayer wiring board as described in Invention 1, The adhesive layer comprises at least two layers, A method for manufacturing a multilayer wiring substrate, characterized in that one of the adhesive layers includes a layer containing the absorbent material. (Invention 3) A method for manufacturing a multilayer wiring board according to invention 1 or 2, The process further includes a first wiring layer formation step of forming a first wiring layer on the first surface of the glass substrate, A method for manufacturing a multilayer wiring substrate, characterized in that the first wiring layer formation step is performed after the modified portion formation step. (Invention 4) A method for manufacturing a multilayer wiring board according to any one of inventions 1 to 3, A first wiring layer formation step in which a first wiring layer is formed on the first surface of the glass substrate, The process further comprises a second support bonding step of bonding a second support to the first wiring layer, A method for manufacturing a multilayer wiring substrate, characterized in that the modification step is performed after the first wiring layer formation step and the second support bonding step. (Invention 5) A method for manufacturing a multilayer wiring board according to any one of inventions 1 to 4, A second wiring layer formation step is performed after the through-hole formation step, in which a second wiring layer is formed on the second surface of the glass substrate from which the first support has been peeled off. A second support peeling step of peeling the aforementioned second support from the glass substrate, A method for manufacturing a multilayer wiring board, further comprising the above. (Invention 6) A method for manufacturing a multilayer wiring board according to any one of inventions 1 to 5, In the first support peeling step, A method for manufacturing a multilayer wiring board, characterized by forming a mark on the interface between the glass substrate and the first support, and applying a force to the glass substrate and the first support in a peeling direction.

[0102] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications are possible without departing from the spirit of the present invention.

[0103] The scope of the present invention is not limited to the illustrative embodiments shown and described, but includes various modifications. For example, the embodiments described above are described in detail for the purpose of illustrating the present invention and are not necessarily limited to those having all the configurations described. Furthermore, it is possible to replace parts of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add configurations from other embodiments to the configuration of one embodiment. In addition, it is possible to add, delete, or replace parts of the configuration of each embodiment with other configurations. Furthermore, this invention also includes all embodiments that produce effects equivalent to those targeted by the present invention. [Explanation of symbols]

[0104] 1: Multilayer wiring board 11: Through hole 12:Through electrode 15: Hydrofluoric acid-resistant metal layer 16: Wiring 21: 1st wiring layer 22: 2nd wiring layer 25: Insulating resin layer 31, 32: Conduction electrode 41, 42: Through electrode connection part 51: Bonding pads for semiconductor devices 52: Solder for semiconductor device bonding 53: Bonding pads for circuit boards 54: Solder for bonding circuit boards 55: Solder Resist 60: Glass substrate 61: First support 62: 1st adhesive layer 63: Laminated Structures 64: Laser absorption layer 65: Laser modification section 70:Second support 71:Second adhesive layer 80: Dielectric layer 90: BGA board 100: Semiconductor devices

Claims

1. In a method for manufacturing a multilayer wiring substrate having a first surface and a second surface facing the first surface, a through hole is formed in the glass substrate. A bonding step of forming an adhesive layer between the first support and the glass substrate, and bonding the second surface of the glass substrate and the first support via the adhesive layer, A modification portion formation step involves irradiating the glass substrate with a laser from the first surface side to form a laser-modified portion on the glass substrate, A first support peeling step of peeling the first support from the glass substrate, The process includes a through-hole forming step, in which through-holes are formed by etching the glass substrate from the second surface side, The adhesive layer includes an absorbing material having a transmittance of a predetermined value or higher with respect to the wavelength of the laser. A method for manufacturing a multilayer wiring substrate, characterized in that the absorbent material is one of the following: ITO (indium tin oxide) fine particles, ATO (antimony tin oxide) fine particles, LaB6 (lanthanum hexaboride), CWO (tungsten cesium oxide) fine particles, cyanine dye, phthalocyanine dye, naphthalocyanine compound, nickel dithiolene complex, squarium dye, quinone compound, diimmonium compound, or azo compound.

2. A method for manufacturing a multilayer wiring board according to claim 1, The adhesive layer comprises at least two layers, A method for manufacturing a multilayer wiring board, characterized in that one of the adhesive layers includes a layer containing the absorbent material.

3. A method for manufacturing a multilayer wiring board according to claim 1, The process further includes a first wiring layer formation step of forming a first wiring layer on the first surface of the glass substrate, A method for manufacturing a multilayer wiring substrate, characterized in that the first wiring layer formation step is performed after the modified portion formation step.

4. A method for manufacturing a multilayer wiring board according to claim 1, A first wiring layer formation step in which a first wiring layer is formed on the first surface of the glass substrate, The process further comprises a second support bonding step of bonding a second support to the first wiring layer, A method for manufacturing a multilayer wiring substrate, characterized in that the modification part formation step is performed after the first wiring layer formation step and the second support bonding step.

5. A method for manufacturing a multilayer wiring board according to claim 4, A second wiring layer formation step is performed after the through-hole formation step, in which a second wiring layer is formed on the second surface of the glass substrate from which the first support has been peeled off. A second support peeling step of peeling the second support from the glass substrate, A method for manufacturing a multilayer wiring board, further comprising the above.

6. A method for manufacturing a multilayer wiring board according to claim 1, In the first support peeling step, A method for manufacturing a multilayer wiring board, characterized by forming a mark on the interface between the glass substrate and the first support, and applying a force to the glass substrate and the first support in a peeling direction.

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