Package substrate and manufacturing method thereof
By using a multi-layer core board structure and similar resin materials, the power integrity, rigidity and reliability issues of the packaging substrate are solved, the production and electrical connection of high-layer substrates are realized, and the overall performance of the packaging substrate is improved.
Patent Information
- Application Number
- CN202410308494.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-18
- Publication Date
- 2025-09-26
AI Technical Summary
The power integrity, rigidity and reliability of existing packaging substrates are poor, mainly due to the limited thickness of the core board and the potential risks of filling the gaps between the embedded device cavities. This leads to poor power integrity, insufficient rigidity, large warping, and the inability to produce fine circuits or high-layer substrates.
A multi-layer core board structure is adopted, including a prepreg material PP structure, a filling layer and a PP laminate. The filling layer is laid on the top side or both sides of the PP structure, and the PP laminate is laid on the top and bottom sides. A cavity structure is opened in the PP structure to place embedded components. Electrical connection is achieved through laser vias and mechanical drilling, avoiding the use of laminated film as a filling layer to improve bonding strength.
It improves the power integrity, rigidity and reliability of the packaging substrate, enables the production of substrates with higher layers, reduces the reliability risk of the substrate, enhances the flatness of the substrate and the circuit yield, and is suitable for high-performance electronic products.
Smart Images
Figure CN120709249A_ABST
Abstract
Description
Technical Field
[0001] The embodiments of the present invention relate to the field of semiconductor packaging, and in particular, to a packaging substrate and a manufacturing method thereof. Background Art
[0002] In substrate design, burying devices (such as capacitors) inside the substrate can reduce power supply and ground impedance, suppress voltage noise, and ensure power integrity. Figure 1 It is a schematic diagram of the structure of the packaging substrate in the related art, such as Figure 1 As shown in the figure, the common substrate structure design and its process flow are as follows: a two-layer core board is made, a cavity is drilled, components are embedded in the cavity, and then the cavity gap is filled with laminated film or prepreg (Prepreg, PP), where the prepreg is also called a semi-cured sheet, and finally the laminated film or PP material is laminated to make other layers.
[0003] The substrate structure in the related art has poor power integrity, rigidity and reliability of the packaging substrate due to problems such as limited core board thickness or potential risks in filling the cavity gap of embedded devices. Summary of the Invention
[0004] The embodiments of the present invention provide a packaging substrate and a manufacturing method thereof, so as to at least solve the problem of poor power integrity, rigidity and reliability of the packaging substrate in the related art.
[0005] According to one embodiment of the present invention, a packaging substrate is provided, comprising: an embedded device and a core board, the core board comprising a prepreg material PP structure, a filling layer, and a PP laminate, wherein the filling layer is laid on the top surface side of the PP structure or on both the top and bottom surfaces of the PP structure, and the PP laminate is laid on the top and bottom surfaces of the PP structure; a cavity structure is opened in the PP structure, and the cavity structure is used to place the embedded device.
[0006] According to another embodiment of the present invention, a method for manufacturing a packaging substrate is provided, comprising: opening a cavity structure on a prepreg material PP structure, and burying embedded devices in the cavity structure; laying a filling layer on the top surface side or on both the top and bottom surfaces of the PP structure; laying a first preset number of PP laminates on the top surface side and the bottom surface side of the PP structure to obtain a core board; laying a second preset number of insulating laminates on the top surface side and the bottom surface side of the core board to obtain the packaging substrate.
[0007] The present invention provides a packaging substrate comprising embedded components and a core board. The core board comprises a polypropylene (PP) structure, a filling layer, and a PP laminate. The filling layer is applied to the top surface of the PP structure or to both the top and bottom surfaces of the PP structure, and the PP laminate is applied to both the top and bottom surfaces of the PP structure. The PP structure includes a cavity for accommodating the embedded components. This solves the problem of poor power integrity, rigidity, and reliability of the packaging substrate, thereby improving the power integrity, rigidity, and reliability of the packaging substrate. BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Figure 1 It is a structural diagram of a packaging substrate in the related art;
[0009] Figure 2 is a flow chart of a method for manufacturing a packaging substrate according to an embodiment of the present invention;
[0010] Figure 3 This is a comparison diagram of the core plate structure of an embodiment of the present invention;
[0011] Figure 4 2 is a schematic structural diagram of a symmetrically structured packaging substrate according to an embodiment of the present invention;
[0012] Figure 5 2 is a schematic structural diagram of an asymmetric packaging substrate according to an embodiment of the present invention;
[0013] Figure 6 Schematic diagram of the processing principle of the PP structure of the package substrate according to an embodiment of the present invention;
[0014] Figure 7 Schematic diagram of the processing principle of the filling layer of the packaging substrate according to an embodiment of the present invention;
[0015] Figure 8 Schematic diagram of the processing principle of the PP lamination of the packaging substrate according to an embodiment of the present invention. DETAILED DESCRIPTION
[0016] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings and in combination with embodiments.
[0017] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.
[0018] like Figure 1The structure of the package substrate shown in the figure has two structural design and process deficiencies in the field of high-performance package substrates: (1) The core board thickness is limited. If the two-layer core board is too thick, the power integrity will be reduced; if the two-layer core board is too thin, the substrate rigidity will be insufficient and the warping will be large. (2) There are potential risks in filling the cavity gap of embedded devices. If PP material is used for filling, PP can only fill thinner two-layer core boards, such as core board thickness ≤ 0.25mm, and the corresponding embedded devices are also relatively thin. When the two-layer core board is thicker, the PP contains glass fiber cloth and cannot fill the cavity gap. The finished substrate will have reliability risks. For example, there is air in the cavity gap, and the embedded device may move. At the same time, due to the poor surface flatness after filling with PP, it is impossible to produce fine circuits or the yield of the produced circuits is too low, and it is also impossible to produce high-layer substrates. Using build-up film can fill thicker cavities and allow for thicker embedded components. However, because the build-up film does not contain fiberglass, its rigidity is poor, requiring a thicker two-layer core board, such as one with a thickness of 0.6mm or greater. Furthermore, the build-up film and core board are made from different resin systems, resulting in weak bonding. More importantly, this thick substrate structure suffers from poor power integrity.
[0019] An embodiment of the present invention provides a packaging substrate, comprising: an embedded device and a core board, the core board comprising a prepreg material PP structure, a filling layer, and a PP laminate, wherein the filling layer is laid on the top surface side of the PP structure or on both the top and bottom surfaces of the PP structure, and the PP laminate is laid on the top and bottom surfaces of the PP structure; a cavity structure is opened in the PP structure, and the cavity structure is used to place the embedded device.
[0020] In an embodiment of the present invention, the original two-layer thick core board in the related art is designed into a multi-layer core board, and the problem of filling the cavity gap of the embedded components in the core board is solved to improve the power integrity of the substrate.
[0021] In an exemplary embodiment, a circuit layer is laid between the PP structure, the filling layer, and the PP laminate layer.
[0022] In this embodiment of the present invention, the circuit layers are distributed between the filling layer and the PP structure, between the PP laminates, between the PP laminates and the insulation buildup layers, and between the insulation buildup layers. Electrical connections are made between the filling layer and the PP structure, between the PP laminates, between the PP laminates and the insulation buildup layers, and between the insulation buildup layers themselves, using laser vias. In this embodiment of the present invention, electrical connections also exist between the PP structures, achieved through mechanical drilling and electroplating.
[0023] In an exemplary embodiment, the filling layer is resin coated copper (RCC) or pure resin material.
[0024] In an embodiment of the present invention, during the production process of the packaging substrate, different materials can be selected for the filling layer, for example, it can be an RCC material or a pure resin material. If a pure resin material is used as the material for the filling layer, the copper foil etching step after laying the filling layer can be omitted. Pure resin material does not contain copper foil, so the copper foil does not need to be etched off later. The production method of the packaging substrate using pure resin material as the material for the filling layer is the same as the production method using RCC as the filling layer, except that the etching step is not required. The remaining steps are the same as the production method using RCC as the filling layer, as well as the thickness requirements and the number of layers.
[0025] In an embodiment of the present invention, when laying the filling layer, the gap between the cavity structure of the PP structure and the embedded device is also filled with the filling layer material, such as RCC material. Similarly, when laying the filling layer on the bottom side of the PP structure, the gap between the cavity structure of the PP structure and the embedded device is also filled with the filling layer material, such as RCC material.
[0026] In an exemplary embodiment, the resin components of the PP structure, the filling layer, and the PP laminate are the same resin.
[0027] In the embodiments of the present invention, the core board's resin composition is the same or similar to that of the RCC and PP, representing the same resin type. In this implementation, laminated film is not used as the filler material because laminated film and PP exhibit low post-press bonding strength, posing reliability risks. Laminated film and PP are from different resin systems.
[0028] In an exemplary embodiment, the package substrate further includes: insulating buildup layers, wherein the insulating buildup layers are laid on the top and bottom surfaces of the core board, and circuit layers are laid between the insulating buildup layers.
[0029] In the embodiment of the present invention, the material of the insulating laminate can be a single material, such as a laminate film or PP, or a combination of two or more materials.
[0030] In an exemplary embodiment, the material type of the insulating build-up layer includes at least one of the following: build-up film; prepreg material PP; resin-coated copper foil RCC; pure resin material.
[0031] In the embodiment of the present invention, the number of insulating layers can be one or multiple layers. Therefore, the insulating layers need to be repeatedly laid until a specified number of layers, i.e., a second predetermined number of layers, is reached. In actual implementation, different materials and numbers of layers can be selected for the insulating layers based on actual needs and processing techniques.
[0032] In an embodiment of the present invention, two packaging substrates of different structural types are provided, namely, a packaging substrate of a symmetrical structure and a packaging substrate of an asymmetrical structure.
[0033] In an exemplary embodiment, when the thickness of the embedded device is equal to the height of the core board, the packaging substrate is a symmetrical structure, and the filling layer is laid on both sides of the top and bottom surfaces of the PP structure; when the thickness of the embedded device is less than the height of the core board, the packaging substrate is an asymmetrical structure, and the filling layer is laid on the top surface side of the PP structure.
[0034] In this embodiment of the present invention, the embedded device's height is less than the PP structure's thickness, resulting in an asymmetric structure. Therefore, during the laser grooving process during the packaging substrate fabrication process, it is not necessary to grooving the PP structure. As long as the resulting cavity structure is large enough to accommodate the embedded device, it is sufficient. For a symmetrical packaging substrate, since the embedded device's height is equal to the PP structure's thickness, grooving the PP structure is sufficient.
[0035] In an exemplary embodiment, when the packaging substrate has a symmetrical structure, the thicknesses of the filling layer on the top and bottom sides of the PP structure are respectively equal, and the thicknesses of the PP laminate on the top and bottom sides of the PP structure are respectively equal; when the packaging substrate has an asymmetrical structure, the sum of the thicknesses of the filling layer and the PP laminate on the top side of the PP structure is equal to the thickness of the PP laminate on the bottom side of the PP structure.
[0036] In an embodiment of the present invention, the number of PP laminates can be one or multiple layers, and the number of insulating laminates can be one or multiple layers. When there is only one PP laminate, for a symmetrically structured packaging substrate, the thickness of the filling layer on the top and bottom sides of the PP structure is equal, and the thickness of the PP laminate on the top and bottom sides of the PP structure is equal. When there are two PP laminates, from the inside to the outside, they are respectively recorded as the first PP laminate and the second PP laminate, the thickness of the filling layer on the top and bottom sides of the PP structure is equal, and the thickness of the PP laminate on the top and bottom sides of the PP structure is equal, and the sum of the thickness of the filling layer and the first PP laminate is equal to the thickness of the second PP laminate. For PP laminates with different numbers of layers, for a symmetrically structured packaging substrate, the thickness relationship always satisfies the quantitative relationship that the thickness of the PP laminate on the top and bottom sides of the PP structure is equal.
[0037] In an embodiment of the present invention, when there is only one PP laminate, for an asymmetric packaging substrate, the sum of the thicknesses of the filling layer and the PP laminate on the top surface of the PP structure is equal to the thickness of the PP laminate on the bottom surface of the PP structure. When there are two PP laminates, for an asymmetric packaging substrate, the sum of the thicknesses of the filling layer and the first PP laminate on the top surface of the PP structure is equal to the thickness of the second PP laminate on the top surface of the PP structure, equal to the thickness of the first PP laminate on the bottom surface of the PP structure, and equal to the thickness of the second PP laminate on the bottom surface of the PP structure.
[0038] The embodiment of the present invention further provides a method for manufacturing a packaging substrate. Figure 2 FIG. 1 is a flow chart of a method for manufacturing a package substrate according to an embodiment of the present invention. Figure 2 As shown, the following steps are included:
[0039] Step S202: forming a cavity structure on the prepreg material PP structure, and embedding the embedded components in the cavity structure;
[0040] In the embodiment of the present invention, laser grooving is first performed on the PP structure to obtain a cavity structure of the PP structure. It should be noted that since the height of the embedded component is less than the thickness of the PP structure, the structure is asymmetric. Therefore, during the laser grooving process, it is not necessary to groove through the PP structure; as long as the obtained cavity structure can accommodate the embedded component, it will suffice. In a symmetric structure, since the height of the embedded component is equal to the thickness of the PP structure, the PP structure is grooved.
[0041] Step S204: laying a filling layer on the top surface or both the top and bottom surfaces of the PP structure;
[0042] In an exemplary embodiment, a filling layer is laid on the top surface side or on both sides of the top surface and bottom surface of the PP structure, including: when the thickness of the embedded device is equal to the height of the PP structure of the core board, the packaging substrate is a symmetrical structure, and the filling layer is laid on both sides of the top surface and bottom surface of the PP structure; when the thickness of the embedded device is less than the height of the PP structure of the core board, the packaging substrate is an asymmetric structure, and the filling layer is laid on the top surface side of the PP structure.
[0043] In an exemplary embodiment, when the material of the filling layer is resin-coated copper foil RCC, after laying the filling layer, the method further includes: etching the copper foil in the filling layer.
[0044] In an embodiment of the present invention, when a filling layer is laid on the top surface of the PP structure, the gap between the cavity structure of the PP structure and the embedded device is also filled with the material of the filling layer, such as RCC material. Similarly, when a filling layer is laid on the bottom surface of the PP structure, the gap between the cavity structure of the PP structure and the embedded device is also filled with the material of the filling layer, such as RCC material.
[0045] Step S206: laying a first preset number of PP laminate layers on the top and bottom sides of the PP structure to obtain a core board;
[0046] In the embodiment of the present invention, the number of PP laminate layers can be one layer or multiple layers. Therefore, the PP laminate layers need to be repeatedly laid to a specified number of layers, that is, a first preset number of layers.
[0047] In an embodiment of the present invention, the core board obtained in the above step S206 is multi-layered. In one embodiment, it may be 6 layers, but the specific number of layers is only an example and is not a specific limitation.
[0048] Step S208 , laying a second preset number of insulating build-up layers on the top and bottom surfaces of the core board to obtain a package substrate.
[0049] In the embodiment of the present invention, the number of insulating layers can be one or multiple layers. Therefore, the insulating layers need to be repeatedly laid until a specified number of layers, ie, a second preset number of layers, is reached.
[0050] The above-described embodiments of the present invention provide a packaging substrate comprising: embedded components and a core board; the core board comprising a polypropylene (PP) structure, a filling layer, and a PP laminate. The filling layer is applied to the top surface of the PP structure or to both the top and bottom surfaces of the PP structure, and the PP laminate is applied to both the top and bottom surfaces of the PP structure. The PP structure includes a cavity structure for accommodating the embedded components. This solves the problem of poor power integrity, rigidity, and reliability of the packaging substrate, thereby improving the power integrity, rigidity, and reliability of the packaging substrate.
[0051] In order to enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention is introduced below in a scenario embodiment in combination with specific structural drawings.
[0052] Example 1
[0053] Figure 3 is a comparison diagram of the core plate structure of the embodiment of the present invention, such as Figure 3 As shown, the left side is a two-layer core board structure in the related art, and the right side is a core board structure provided by an embodiment of the present invention.
[0054] In the embodiment of the present invention, Figure 3 As shown, while embedding the components, the original 2-layer thick core board in the related art is designed into a multi-layer core board, and the problem of filling the cavity gap of the embedded components in the core board is solved at the same time to improve the power integrity of the substrate.
[0055] In an embodiment of the present invention, after the components (active or passive) are embedded in the cavity structure of the core board, RCC or pure resin is laminated first (for filling and bonding, and this resin is the same system as the resin of the core board), and then PP laminated layers and copper foil are laminated to form a multi-layer core board structure, and then laminated laminated films are laminated as insulating laminates to produce a high-layer package substrate with embedded components and a multi-layer core board.
[0056] In the embodiments of the present invention, the number of PP laminated layers can be one or multiple layers, and the number of insulation laminated layers can be one or multiple layers. In the subsequent embodiments, the example of two PP laminated layers (two layers each on the top and bottom sides) and the example of five insulation laminated layers (five layers each on the top and bottom sides) are used for explanation.
[0057] In an embodiment of the present invention, two packaging substrates of different structural types are provided, namely, a packaging substrate of a symmetrical structure and a packaging substrate of an asymmetrical structure. Figure 4 FIG. 1 is a schematic structural diagram of a symmetrical package substrate according to an embodiment of the present invention. Figure 4 As shown in the figure, the multi-layer core board has 6 layers, and the laminated film has 5 layers on the top and 5 layers on the bottom, for a total of 16 layers. The symmetrical structure means that the height of the embedded device is the same as the thickness of the core board's PP structure, such as Figure 4 As shown, the height of the embedded components and the thickness of the core board's PP structure are both 0.6 mm.
[0058] In the embodiment of the present invention, Figure 4 As shown, there are 1 layer of copper, 2 layers of copper, 3 layers of copper... 16 layers of copper, which are the circuit layers in the above embodiment of the present invention. In the embodiment of the present invention, the circuit layers are distributed between the filling layer and the PP structure, between the PP laminates, between the PP laminates and the insulating laminates, and between the insulating laminates. There are electrical connections between the filling layer and the PP structure, between the PP laminates, between the PP laminates and the insulating laminates, and between the insulating laminates, and the electrical connections are achieved through laser via connections. In the embodiment of the present invention, there are also electrical connections between the PP structures, and the implementation method is through mechanical drilling and electroplating. Among them, in the embodiment of the present invention, GL102 represents the material model of the insulating laminate. GEA-770G and E770G represent the material models of PP. MCF LC01 represents the material model of RCC. As shown Figure 4 As shown, the initial 2-layer core board is the PP structure in the embodiment of the present invention, the 6-layer multi-layer core board is the core board structure in the embodiment of the present invention, and the 16-layer substrate is the packaging substrate structure finally obtained in the embodiment of the present invention.
[0059] In the embodiment of the present invention, Figure 4 As shown, the initial two-layer core board is the two-layer core board in the related art, which corresponds to the multi-layer core board of the embodiment of the present invention, namely the multi-layer core board. The final package substrate is as shown in FIG. Figure 4 The figure shows a 16-layer substrate. In the embodiments of the present invention, the specific number of layers is for illustration only and is not a limitation. In actual implementation, the actual number of layers, including the number of PP laminates, insulation buildup layers, and substrate layers, can be determined based on actual functional requirements or processing conditions.
[0060] Figure 5 FIG. 1 is a schematic structural diagram of an asymmetric packaging substrate according to an embodiment of the present invention. Figure 5 As shown in the figure, the asymmetric structure means that the height of the embedded device is different from the thickness of the core board's PP structure. The height of the embedded device is 0.6mm and the thickness of the core board is 1.2mm. Figure 5 As shown, since the height of the embedded components is less than the thickness of the PP structure of the core board, no filling layer is laid on the bottom side of the core board.
[0061] Example 2
[0062] In the second embodiment, a method for manufacturing a packaging substrate with a symmetrical structure in the above embodiment is introduced.
[0063] Method for manufacturing a symmetrical structure packaging substrate:
[0064] The core board material model is E770G, the corresponding RCC material model is MCF LC01, the pure resin material model is AS770G, and the PP material model is GEA-770G. It can be seen that the resin components of the core board, RCC, pure resin, and PP are the same resin system. Among them, the thickness of the embedded device is equal to the thickness of the PP structure of the core board. It should be noted that in the embodiments of the present invention, the two-layer core board in the related art is referred to as the core board. This is not to limit the difference in the number of layers, but is only for the purpose of name.
[0065] During the manufacturing process of the packaging substrate, different materials can be selected for the filling layer. In the embodiment of the present invention, two types of material embodiments are provided, namely RCC material and pure resin material.
[0066] Figure 6 FIG. 1 is a schematic diagram of the processing principle of the PP structure of the package substrate of an embodiment of the present invention. Figure 6 As shown, first, laser grooves are made on the PP structure to obtain the cavity structure of the PP structure, and then adhesive tape is placed on the top surface of the PP structure, and the core board is turned over so that the top surface faces downward. Then, the embedded device 110 is embedded in the cavity structure. Figure 6 As shown, the 2-layer core board 100 is the core board in the embodiment of the present invention, and the 8-layer copper and 9-layer copper are the structure of the circuit layer in the embodiment of the present invention. The number of layers is the number of layers in a fixed order after the packaging substrate is finally formed, and it does not limit the specific number of layers. In the embodiment of the present invention, the number of layers is only an example for illustration and is not specifically limited. In the actual implementation process, different numbers of layers can be determined according to actual needs or processing technology.
[0067] Figure 7 FIG. 1 is a schematic diagram showing the processing principle of the filling layer of the package substrate according to an embodiment of the present invention. Figure 7As shown, a filler layer (in this embodiment, RCC) is first placed on the bottom surface of the PP structure. A pre-pressing operation is then performed to secure the embedded components. The PP structure is then flipped so that the top surface faces upward. The adhesive tape on the top surface is removed, and the RCC is placed on the top surface of the PP structure. A full press operation is then performed to etch away the copper foil in the RCC.
[0068] like Figure 7 As shown, in this embodiment of the present invention, the thickness of the filling layer on the top and bottom sides of the PP structure is equal. In this embodiment of the present invention, when the filling layer is laid on the top side of the PP structure, the gap between the cavity structure of the PP structure and the embedded device is also filled with the material of the filling layer, such as RCC material. Similarly, when the filling layer is laid on the bottom side of the PP structure, the gap between the cavity structure of the PP structure and the embedded device is also filled with the material of the filling layer, such as RCC material.
[0069] Figure 8 FIG. 1 is a schematic diagram showing the processing principle of the PP lamination of the package substrate according to an embodiment of the present invention. Figure 8 As shown, PP laminates and copper foil (i.e., circuit layers) are stacked (laid) on the top and bottom sides of the PP structure at the same time, and then a full pressing operation is performed, and the filling layer and PP laminate are laser drilled, electroplated, and circuits are made to achieve laser via connections between different filling layers and PP laminates to achieve electrical connections. At this point, the core board of the embodiment of the present invention is obtained. In the embodiment of the present invention, the number of PP laminates can be one layer or multiple layers, so it is necessary to repeatedly lay the PP laminate to a specified number of layers, i.e., a first preset number of layers. As shown in FIG. Figure 8 As shown, the number of PP laminates is 2.
[0070] It should be noted that, in the embodiments of the present invention, the thicknesses of different layers such as the filling layer or the circuit layer are exemplified in the drawings. For example, Figure 4 The thickness of the RCC filling layer is 25um, the thickness of the 8-layer copper is 25um, the thickness of the 3-layer copper is 15um, the thickness of the PP laminate is 40um or 60um, and the thickness of the insulation buildup is 30um. These are all examples and are not specific restrictions on thickness. In actual implementation, the thickness of each layer can be set according to actual conditions. For example, the thickness of the 3-layer copper may not be 15um. However, in the embodiments of the present invention, the quantitative relationship between the thicknesses of the different layers involved is necessary, including but not limited to the following: Figure 8 The thickness of the PP laminate on the top and bottom sides of the PP structure shown is correspondingly equal.
[0071] like Figure 8As shown, the number of PP laminates is 2. In the embodiment of the present invention, they are respectively recorded as the first PP laminate and the second PP laminate from the inside out. The sum of the thickness of the filling layer on the top side of the PP structure and the thickness of the first PP laminate is equal to the sum of the thickness of the filling layer on the bottom side of the PP structure and the thickness of the first PP laminate, and the sum of the thickness values is equal to the thickness of the second PP laminate on the top side of the PP structure and equal to the thickness of the second PP laminate on the bottom side of the PP structure.
[0072] In the embodiment of the present invention, what needs to be limited and determined is the thickness of the PP laminate. The specific number of layers of the PP laminate can be determined according to actual conditions, as long as the thickness meets actual needs or process processing capabilities.
[0073] In the embodiments of the present invention, the resin composition of the core plate is the same as or similar to that of the RCC and PP, representing the same resin type. In this implementation, laminated film is not used as the filler material because the post-press bonding strength between laminated film and PP is weak, posing a reliability risk. The resins in laminated film and PP belong to different resin systems.
[0074] In an embodiment of the present invention, insulating laminates are laid on the top and bottom surfaces of the core substrate, using laminated film as the insulating laminate material. In actual implementation, different materials can be selected for the insulating laminates based on actual needs and process requirements. After laying the second predetermined number of insulating laminates, solder masking, surface pad processing, cutting, and inspection are performed to obtain the finished package substrate. In an embodiment of the present invention, the number of insulating laminates can be one or more, and therefore, the insulating laminates need to be repeatedly laid until the specified number of layers, i.e., the second predetermined number of layers, is reached.
[0075] In an embodiment of the present invention, if a pure resin material is used as the filling layer, the copper foil etching step after laying the filling layer can be omitted. The pure resin material model can be AS770G: 25um, without copper foil, and the copper foil does not need to be etched away later. The method for manufacturing a package substrate using a pure resin material as the filling layer is the same as the method for manufacturing a RCC filling layer, except that the etching step is not required. The remaining steps, including thickness requirements and number of layers, are the same as those for manufacturing a package substrate using RCC as the filling layer, and are not further described here.
[0076] In related technologies, the process flow for producing a two-layer core board is as follows: The two-layer core board is manufactured using a subtractive process, with built-up film or polypropylene (PP) used as the raw material for embedded components and cavity filling. Other layers, such as the insulation layer, are manufactured using a semi-additive or modified semi-additive process, with the corresponding primary raw materials being build-up film or polypropylene (PP). When build-up film is used to produce fine circuits, the semi-additive process is used. When polypropylene is used to produce general circuits, the modified semi-additive process is used. This is because the properties of PP material prevent the direct use of a semi-additive process for fine circuits.
[0077] In an embodiment of the present invention, the process flow of the multi-layer core board is as follows: the core board manufacturing process is a subtractive method, the raw material is a copper clad laminate, the material for embedded devices and filling cavity gaps is RCC or pure resin, the main raw material for the core board is PP, and the process is a subtractive method. The manufacturing process of other layers such as insulating layers is a semi-additive method, and the main raw material is a laminate film.
[0078] Example 3
[0079] In the third embodiment, a method for manufacturing a packaging substrate with an asymmetric structure is introduced.
[0080] First, laser grooving is performed on the PP structure to obtain a cavity structure. It should be noted that since the height of the embedded device is less than the thickness of the PP structure, the structure is asymmetric. Therefore, during the laser grooving process, it is not necessary to groove through the PP structure; as long as the cavity structure can accommodate the embedded device, it will suffice. In the symmetrical structure of Example 2, because the height of the embedded device is equal to the thickness of the PP structure, the PP structure is grooved.
[0081] After obtaining the cavity structure, there is no need to flip the PP structure, and the embedded components can be placed directly. Then, a filling layer is stacked on the top side (that is, the side where the embedded components are placed). The material of the filling layer can be RCC material or pure resin material, and there is no restriction here. After laying the filling layer, full pressing operation is performed. When RCC material is used as the filling layer, the RCC copper foil needs to be etched off. Then, PP lamination and copper foil are stacked on both sides at the same time, and full pressing operation, laser drilling, electroplating, circuit production, and PP lamination are repeated to the specified number of layers, that is, the first preset number of layers, to obtain the core board.
[0082] After obtaining the core board, insulating laminates are laid on the top and bottom sides of the core board. In the embodiment of the present invention, laminated film is used as the material of the insulating laminate. In actual implementation, different materials can be selected as the insulating laminate according to actual needs and process processing. After laying the second preset number of insulating laminates, solder mask, surface pad processing, cutting, inspection and other processing steps are carried out to obtain the finished package substrate. Figure 5In the embodiment of the present invention, the number of insulating layers can be one or multiple layers, and therefore, the insulating layers need to be repeatedly laid to a specified number of layers, ie, a second preset number of layers.
[0083] In the embodiment of the present invention, for the packaging substrate with an asymmetric structure, the sum of the thickness of the filling layer and the PP laminate on the top surface side of the PP structure is equal to the thickness of the PP laminate on the bottom surface side of the PP structure. Figure 5 As shown, in the case where the PP laminate includes a first PP laminate and a second PP laminate, which are respectively recorded as the first PP laminate and the second PP laminate from the inside out, the sum of the thickness of the top surface after RCC pressing and the thickness of the top surface after the first PP laminate is equal to the thickness of the bottom surface first PP laminate, equal to the thickness of the top surface second PP laminate, and equal to the thickness of the bottom surface second PP laminate.
[0084] In Example 3, the core board's resin composition is the same or similar to that of the RCC and PP, representing the same resin type. In this embodiment, laminated film is not used as the filler material because the post-press bonding strength between laminated film and PP is weak, posing a reliability risk. Laminated film and PP belong to different resin systems.
[0085] In summary, the embodiments of the present invention provide a packaging substrate and a method for manufacturing the same. The packaging substrate can be widely used in various semiconductor packaging fields and is suitable for scenarios with high requirements for the power integrity of electronic products. The packaging substrate structure includes embedded devices, a core board, an insulating laminate, etc., which can reduce the thickness of the core board, increase the hole density, enhance the rigidity of the substrate, reduce thermal stress, reduce the overall size of the product, and improve the power integrity. In view of the various problems such as the substrate reliability risk and the inability to produce high-layer-count substrates in the basic packaging processing technology in the related art, the basic packaging manufacturing method of the present invention can solve key problems such as cavity gap filling and the formation of multi-layer core boards, and can realize the production of high-reliability, high-layer-count substrates of the above-mentioned design ideas.
[0086] The packaging substrate provided by the embodiment of the present invention has the following advantages: (1) The thickness of the core board is reduced. The thickness of the original core board is reduced by increasing the number of core board layers. (2) The hole density of the core board is increased. The PP structure in the core board in the embodiment of the present invention is thinner than the two-layer core board in the related art, and smaller through holes can be processed. The other layers can be processed with laser blind holes. Compared with the two-layer core board in the related art, the core board structure of the embodiment of the present invention can significantly improve the hole density. (3) The rigidity of the substrate is enhanced. The core board in the embodiment of the present invention has better rigidity than the two-layer core board in the related art. (4) The thermal stress of the substrate is reduced. Since smaller through holes can be processed and the hole diameter becomes smaller, the core board in the embodiment of the present invention can reduce the thermal stress of the substrate. (5) The product size is reduced. The embedded components can reduce the number of surface-mounted components. (6) The power integrity of the product is improved. The core board in the embodiment of the present invention can improve the power integrity by increasing the number of core board layers, reducing the thickness of each core board layer, and embedding components.
[0087] The packaging substrate manufacturing method provided by the embodiment of the present invention has the following advantages: (1) The reliability risk of the substrate is reduced by filling the gap between the cavity structure and the embedded device when laying the filling layer. (2) The core board has good flatness, which can be used to produce fine circuits and improve the circuit yield, and can also produce high-layer substrates. (3) Each layer of the multi-layer core board, such as the PP laminate and the insulating base layer, adopts a subtractive process to ensure low cost.
[0088] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the principles of the present invention are intended to be within the scope of protection of the present invention.
Claims
1. A packaging substrate, characterized in that: include: Embedded components and core board, the core board includes a prepreg material PP structure, a filling layer, and a PP laminate, wherein: The filling layer is laid on the top surface side of the PP structure or on both the top surface and bottom surface of the PP structure, and the PP pressing layer is laid on the top surface side and bottom surface side of the PP structure; A cavity structure is provided in the PP structure, and the cavity structure is used to place the embedded device.
2. The packaging substrate according to claim 1, wherein: in, Circuit layers are laid between the PP structure, the filling layer, and the PP laminate layer.
3. The packaging substrate according to claim 1, wherein: in, The filling layer is resin-coated copper foil RCC or pure resin material.
4. The packaging substrate according to claim 1, wherein: in, The resin components of the PP structure, the filling layer and the PP laminate are the same resin.
5. The packaging substrate according to claim 1, wherein: The package substrate further includes an insulating buildup layer, wherein: The insulating buildup layers are laid on the top and bottom surfaces of the core board, and circuit layers are laid between the insulating buildup layers.
6. The packaging substrate according to claim 5, wherein: in, The material type of the insulating layer includes at least one of the following: Laminated film; prepreg material PP; resin coated copper foil RCC; pure resin material.
7. The packaging substrate according to claim 1, wherein: in, When the thickness of the embedded device is equal to the height of the PP structure of the core board, the package substrate is a symmetrical structure, and the filling layer is laid on both sides of the top and bottom surfaces of the PP structure; In the case that the thickness of the embedded device is smaller than the height of the PP structure of the core board, the packaging substrate is an asymmetric structure, and the filling layer is laid on the top surface side of the PP structure.
8. The packaging substrate according to claim 7, wherein: in, In the case where the package substrate has a symmetrical structure, the thicknesses of the filling layer on the top and bottom sides of the PP structure are respectively equal, and the thicknesses of the PP laminate on the top and bottom sides of the PP structure are respectively equal; In the case where the packaging substrate has an asymmetric structure, the sum of the thicknesses of the filling layer and the PP laminate on the top surface side of the PP structure is equal to the thickness of the PP laminate on the bottom surface side of the PP structure.
9. A method for manufacturing a packaging substrate, characterized in that: include: A cavity structure is formed on the prepreg material PP structure, and embedded components are embedded in the cavity structure; Laying a filling layer on the top surface side or on both the top surface and the bottom surface of the PP structure; Laying a first preset number of PP laminate layers on the top and bottom sides of the PP structure to obtain a core board; A second preset number of insulating build-up layers are laid on the top and bottom surfaces of the core board to obtain the packaging substrate.
10. The method according to claim 9, characterized in that A filling layer is laid on the top surface side or on both the top surface and the bottom surface of the PP structure, including: In the case where the thickness of the embedded device is equal to the height of the PP structure of the core board, the package substrate is a symmetrical structure, and the filling layer is laid on both sides of the top and bottom surfaces of the PP structure; In the case that the thickness of the embedded device is smaller than the height of the PP structure of the core board, the packaging substrate is an asymmetric structure, and the filling layer is laid on the top surface side of the PP structure.
11. The method according to claim 9, characterized in that In the case where the material of the filling layer is resin-coated copper foil RCC, after laying the filling layer, the method further includes: The copper foil in the filling layer is etched.