Circuit board with embedded component

Abstract

The utility model provides a circuit board with an embedded element, which comprises a substrate unit, a layer-adding material layer and a conducting layer, the substrate unit comprises a substrate body, a filling material layer and an electronic element, the filling material layer is arranged in an accommodating space of the substrate body, the electronic element is embedded in the filling material layer, and the conducting layer is arranged in the accommodating space of the substrate body. The filling material layer is provided with at least one first hole extending from the surface of the filling material layer to at least one electrode of the electronic component, and the layer-adding material layer is arranged on the surface of the substrate unit and the hole wall of the at least one first hole and is provided with at least one second hole. The at least one second hole extends from the surface of the build-up material layer to the at least one electrode of the electronic component, and the conductive layer is arranged on the surface of the build-up material layer and extends along the at least one second hole to be connected with the at least one electrode of the electronic component.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of circuit boards, especially the circuit board with internal component. BACKGROUND

[0002] Please refer to Figure 2A The schematic diagram of a core plate (Core) 20 in the existing multilayer circuit board is shown, the core plate 20 is thin core, its thickness can be 0.1 to 0.6 millimeter, and the core plate 20 is embedded with multiple electronic components 21, the internal structure of the core plate 20 can refer to Figure 2B , a first build-up material layer 201, a second build-up material layer 202 and a third build-up material layer 203 are respectively arranged on the top surface, bottom surface and internal accommodating space of a substrate body 200, the material of the first, second and third build-up material layers 201, 202, 203 is same, for example, can be epoxy, polypropylene (PP) or ABF (Ajinomoto Build-up Film), wherein the third build-up material layer 203 is embedded with an electronic component 21, the surface of the second build-up material layer 202 is provided with multiple conductive layers 204, each conductive layer 204 extends inward to connect each electrode 210 of the electronic component 21.

[0003] With the functional improvement of electronic products, for example, the circuit board for high-performance computing (HPC), the size and thickness of its circuit board may increase accordingly, please refer to Figure 3A The number of electronic components 31 embedded in the core plate 30 is more and the arrangement density is more compact, so the core plate 30 must use thick core to provide sufficient rigidity, the thickness of the core plate 30 is greater than 1 millimeter, for example. The internal structure of the core plate 30 is shown below by a manufacturing process example. Figure 3A

[0004] Please refer to Figure 3B A substrate body 300 is provided. Please refer to Figure 3C An accommodating space 301 is formed in the substrate body 300, and the accommodating space 301 penetrates the top surface and bottom surface of the substrate body 300. Please refer to Figure 3D A tape 302 is arranged on the bottom surface of the substrate body 300, and an electronic component 31 is placed in the accommodating space 301 and located on the tape 302.

[0005] Please refer to Figure 3E ​, a filling material is filled in the accommodating space 301 of the substrate body 300 to form a filling material layer 303, and the electronic component 31 is embedded in the filling material layer 303. The filling material may be, for example, a liquid or solid molding material. After solidification, the filling material layer 303 can be combined with the inner wall surface of the substrate body 300 and fix the electronic component 31. Figure 3F , the adhesive tape 302 is removed from the substrate body 300, and the top surface and bottom surface of the substrate body 300 and the filling material layer 303 are planarized. Figure 3G , after the metal layer 304 on the surface of the substrate body 300 is patterned to form a circuit, a first build-up material layer 305 and a second build-up material layer 306 are formed by double-sided pressing. The materials of the first and second build-up material layers 305, 306 may be, for example, epoxy, polypropylene (PP), or ABF (Ajinomoto Build-up Film) with or without glass fiber.

[0006] Please refer to Figure 3H and Figure 3I , the surface of the second build-up material layer 306 is drilled to form two holes V, the positions of the two holes V correspond to the positions of the two electrodes 310 of the electronic component 31 respectively. The two holes V extend from the surface of the second build-up material layer 306 inwardly and extend to the two electrodes 310 of the electronic component 31 through the filling material layer 303, so that the two electrodes 310 can be exposed to the two holes V respectively. The drilling method of the two holes V may be, for example, laser drilling. Figure 3J , a conductive layer 307 is formed on the first build-up material layer 305 and the second build-up material layer 306 respectively. A first conductive layer 3071 and a second conductive layer 3072 can be filled into the two holes V respectively and substantially connected to the two electrodes 310 of the electronic component 31.

[0007] The second additive layer 306 and the filler layer 303 are made of different materials and have different material properties. Generally, the additive and filler materials mainly consist of resin, glass powder, hardener, and other additives, and the coefficient of thermal expansion (CTE) of the resin is greater than that of the glass powder. The filler material should ideally have a lower CTE to match the CTE of the embedded electronic components 21 and 31. Therefore, the glass powder density and particle diameter of the filler material are usually different from those of the additive layer. On the other hand, because the glass powder particle diameter of the additive layer is smaller, it helps to improve the smoothness of the electroplated metal layer. For example, the average diameter of the glass powder particles in the additive layer is 0.5 micrometers, with a maximum diameter of 1 micrometer; the average diameter of the glass powder particles in the filler material is 8 micrometers, with a maximum diameter of 25 micrometers. This description is for reference only and is not a limitation.

[0008] However, Figure 3H When laser drilling is performed to form the hole V, the laser ablation path includes the interface between the dissimilar materials of the filler material layer 303 and the second reinforcement material layer 306. The glass powder particles exposed in the filler material layer 303 outside the hole V are relatively easy to detach. Therefore, please refer to... Figure 3I An irregular discontinuity 308 will be formed at the junction of the filler material layer 303 and the second additive material layer 306, making the hole wall of the hole V a non-smooth and non-uniform surface. This will cause the first and second conductive layers 3071 and 3072 formed by subsequent electroplating to have poor quality (e.g., cavitation) and reliability problems (e.g., conductive layer breakage or cracks). Utility Model Content

[0009] In view of this, the main objective of this utility model is to provide a circuit board with embedded components, in order to overcome the poor quality and reliability problems caused by the structure of existing circuit boards involving holes, filling material layers and additive material layers.

[0010] The circuit board with embedded components of this utility model includes:

[0011] A substrate unit includes a substrate body, a filler material layer and an electronic component. The substrate body has an accommodating space, the filler material layer is disposed in the accommodating space, the electronic component is embedded in the filler material layer, and the filler material layer has at least one first hole, the at least one first hole extending from the surface of the filler material layer to at least one electrode of the electronic component.

[0012] An add-in material layer is disposed on the surface of the substrate unit and the wall of the at least one first hole, and has at least one second hole inside the at least one first hole, the at least one second hole extending from the surface of the add-in material layer to the at least one electrode of the electronic component; and

[0013] a conductive layer disposed on a surface of the build-up material layer and extending along the at least one second hole to connect the at least one electrode of the electronic component.

[0014] According to the circuit board structure of the present application, the build-up material layer is disposed on the hole wall of each first hole, and the inner side of each first hole forms each second hole, that is, the inner wall surface of the filling material layer (i.e. the hole wall of each first hole) is covered by the build-up material layer, and the filling material layer is not exposed to each second hole, and the conductive layer extends along each second hole in the build-up material layer to connect the electrode of the electronic component. Therefore, the present application does not involve the connection interface of different materials on the path of each second hole, and does not produce the stepped structure, so that the hole wall of each second hole can form a smooth and uniform surface, so that the conductive layer extends along each second hole to connect the electrode of the electronic component, effectively overcoming the quality problems and reliability problems caused by the existing structure. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figures 1A-1H The present application has an embodiment of a circuit board with an embedded component manufacturing process flow diagram.

[0016] Figure 1I The present application has an embodiment of a circuit board with an embedded component manufacturing process flow diagram.

[0017] Figure 1J : Figure 1I partial enlarged view.

[0018] Figure 2A The present application has an embodiment of a circuit board with an embedded component manufacturing process flow diagram.

[0019] Figure 2B The present application has an embodiment of a circuit board with an embedded component manufacturing process flow diagram.

[0020] Figure 3A The present application has an embodiment of a circuit board with an embedded component manufacturing process flow diagram.

[0021] Figures 3B-3H The present application has an embodiment of a circuit board with an embedded component manufacturing process flow diagram.

[0022] Figure 3I : Figure 3H partial enlarged view.

[0023] Figure 3J The present application has an embodiment of a circuit board with an embedded component manufacturing process flow diagram.

[0024] BRIEF DESCRIPTION OF DRAWINGS

[0025] 100, 200, 300: substrate body; 101: base material; 102, 304: metal layer; 103: through hole; 104, 301: accommodation space; 105, 302: adhesive tape; 106, 21, 31: electronic component; 1061, 210, 310: electrode; 107, 303: filling material layer; 108: build-up material layer; 109, 204, 307: conductive layer; 1091: pad portion; 1092: column portion; 20, 30: core board; 201, 305: first build-up material layer; 202, 306: second build-up material layer; 203: third build-up material layer; 3071: first conductive layer; 3072: second conductive layer; 308: stepped portion; V1: first hole; V2: second hole; V: hole. DETAILED DESCRIPTION

[0026] The embodiment of the circuit board with an embedded component includes a substrate unit, a build-up material layer, and a conductive layer. The substrate unit is internally provided with a filling material layer, and the filling material layer embeds an electronic component. The conductive layer can stably connect the electrodes of the electronic component. For example, the circuit board can be used as a core board in a multi-layer circuit board. On the other hand, the circuit board does not limit the thickness of the core board, the size, spacing, and arrangement density of the electronic component, and is suitable for thin and thick core boards.

[0027] The structure of the circuit board is not limited to the manufacturing process.

[0028] Please refer to Figure 1A , a substrate body 100 is provided, which includes a base material 101 and two metal layers 102 formed on opposite surfaces (such as the top and bottom surfaces) of the base material 101, respectively. The two metal layers 102 can be electrically connected to each other through through holes 103 (PTH). Please refer to Figure 1B , an accommodation space 104 is formed in the substrate body 100, which penetrates the top and bottom surfaces of the substrate body 100. Please refer to Figure 1C , an adhesive tape 105 is arranged on the bottom surface of the substrate body 100, and an electronic component 106 is placed in the accommodation space 104 and located on the adhesive tape 105.

[0029] Please refer to Figure 1D, fill a filling material into the accommodating space 104 of the substrate body 100 to form a filling material layer 107, and the electronic component 106 is embedded in the filling material layer 107, and the filling material layer 107 after solidification can be combined with the inner wall surface of the substrate body 100 and fix the electronic component 106, for example, the filling material can be epoxy, and the filling method of the filling material can be one of dispensing, printing, lamination and molding. Please refer to Figure 1E , the adhesive tape 105 is removed from the substrate body 100, and the top surface and the bottom surface of the substrate body 100 and the filling material layer 107 can be planarized by brushing, plasma, sandblasting or chemical mechanical grinding (CMP), that is, the top surface of the substrate body 100 and the top surface of the filling material layer 107 are flush, and the bottom surface of the substrate body 100 and the bottom surface of the filling material layer 107 are flush.

[0030] Please refer to Figure 1F , the surface (top surface and / or bottom surface) of the filling material layer 107 is drilled to form at least one hole (defined as at least one first hole V1 below), the at least one first hole V1 extends from the surface (top surface and / or bottom surface) of the filling material layer 107 to at least one electrode 1061 of the electronic component 106, so that the electrode 1061 of the electronic component 106 can be exposed to the first hole V1, wherein the number of the at least one first hole V1 can be one or more and formed on the top surface and / or the bottom surface of the filling material layer 107, the utility model takes two first holes V1 as an example, and the two first holes V1 are formed on the bottom surface of the filling material layer 107. The drilling method of the at least one first hole V1 is, for example, laser drilling (Laser drilling or Laser skiving) and proper cleaning, for example, cleaning by plasma, deslagging or water washing. In the utility model, the substrate unit comprises the substrate body 100, the filling material layer 107 and the electronic component 106 as described above.

[0031] Please refer to Figure 1G , the metal layer 102 is patterned, and a build-up material layer 108 is formed on the top surface and the bottom surface of the substrate unit, for example, the build-up material layer 108 can be formed by double-sided lamination, wherein the build-up material layer 108 also fills into the at least one first hole V1.

[0032] Please refer to Figure 1HThe surface of the build-up material layer 108 corresponding to the at least one first hole V1 is drilled, and the build-up material layer 108 remaining on the hole wall of the at least one first hole V1 forms at least one hole (hereinafter defined as at least one second hole V2). The at least one second hole V2 is drilled, for example, by laser drilling, and is cleaned, for example, by plasma, desmear, or water washing. That is, this step only performs laser drilling on the build-up material layer 108, and the laser only ablates the single material of the build-up material layer 108. Each second hole V2 is a hole space surrounded by the inner wall surface of the build-up material layer 108. Each second hole V2 has a one-to-one correspondence with each first hole V1, is located inside each corresponding first hole V1, has a smaller diameter than each corresponding first hole V1, and extends from the surface of the build-up material layer 108 to the at least one electrode 1061 of the electronic element 106, so that the electrode 1061 of the electronic element 106 can be exposed to the at least one second hole V2.

[0033] Please refer to Figure 1I and Figure 1J A conductive layer 109 is formed on the build-up material layer 108, for example, by plating. The conductive layer 109 fills the at least one second hole V2 and connects the electrode 1061 of the electronic element 106. Subsequently, other circuit layers and other build-up structures can be manufactured to form a complete multi-layer circuit board or a composite substrate.

[0034] In summary, the circuit board with an embedded element embodiment includes a substrate unit, a build-up material layer 108, and a conductive layer 109. The substrate unit includes a substrate body 100, a filler material layer 107, and an electronic element 106.

[0035] The substrate body 100 has a receiving space 104 that can pass through the top surface and the bottom surface of the substrate body 100. The filler material layer 107 is disposed in the receiving space 104 of the substrate body 100, and the top surface and the bottom surface of the filler material layer 107 can be flush with the top surface and the bottom surface of the substrate body 100, respectively. The electronic element 106 is embedded in the filler material layer 107. For example, the electronic element 106 can be a multi-layer ceramic capacitor (MLCC), a silicon capacitor, an integrated circuit element (IC), an inductor, or the like. The electronic element 106 of the present application is taken as an example with two electrodes 1061.

[0036] The filling material layer 107 is formed with at least one first hole V1 extending from the surface (top surface and / or bottom surface) of the filling material layer 107 to at least one electrode 1061 of the electronic element 106. In other words, the top surface of the filling material layer 107 can form the first hole V1, or the bottom surface of the filling material layer 107 can form the first hole V1, or both the top surface and the bottom surface of the filling material layer 107 can form the first hole V1. Figure 1I For example, the bottom surface of the filling material layer 107 forms two first holes V1 extending inwardly from the bottom surface of the filling material layer 107 to two electrodes 1061 of the electronic element 106, respectively, so that the two electrodes 1061 are exposed to the two first holes V1, respectively. In an embodiment, the diameter of the at least one first hole V1 tapers inwardly from the surface of the filling material layer 107.

[0037] The build-up material layer 108 is disposed on the surface of the substrate unit (i.e. the surface of the metal layer 102) and the hole wall of the at least one first hole V1, and has at least one second hole V2 on the inner side of the at least one first hole V1, the at least one second hole V2 extending from the surface of the build-up material layer 108 to the at least one electrode 1061 of the electronic element 106. Each second hole V2 is a hole space surrounded by the inner wall surface of the build-up material layer 108. Each second hole V2 has a one-to-one correspondence with each first hole V1. Each second hole V2 is formed on the inner side of each corresponding first hole V1. The diameter of each second hole V2 is smaller than the diameter of each corresponding first hole V1. In an embodiment, the diameter of the at least one second hole V2 tapers inwardly from the surface of the filling material layer 107 to correspond to the diameter pattern of the at least one first hole V1. The conductive layer 109 is disposed on the surface of the build-up material layer 108 and extends along the at least one second hole V2 to connect the at least one electrode 1061 of the electronic element 106.

[0038] The components of the build-up material layer 108 and the filling material layer 107 basically include resin, glass powder, hardening agent and other additives, and the coefficient of thermal expansion (CTE) of the resin is greater than the coefficient of thermal expansion of the glass powder. The coefficient of thermal expansion of the filling material layer 107 is smaller than the coefficient of thermal expansion of the build-up material layer 108, so the density and particle diameter of the glass powder of the filling material layer 107 are different from the density and particle diameter of the glass powder of the build-up material layer 108.

[0039] As shown in FIG. 1, the electronic element 106 is disposed on the surface of the metal layer 102 of the substrate unit 100. The electronic element 106 is electrically connected to the metal layer 102 through the conductive layer 109. The electronic element 106 is electrically connected to the metal layer 102 through the conductive layer 109. Figure 1JAs shown, the conductive layer 109 can include a pad portion 1091 and a column portion 1092 connected to the pad portion 1091, the conductive layer 109 is defined as the pad portion 1091 at the portion on the surface of the build-up material layer 108, and the conductive layer 109 is defined as the column portion 1092 at the portion extending along each second hole V2, so that the conductive layer 109 is substantially connected to the electrode 1061 of the electronic component 106 through the column portion 1092, the portion of the build-up material layer 108 formed on the hole wall of each first hole V1 (i.e. the inner wall surface of the filling material layer 107) is defined as a barrier portion 1081, the barrier portion 1081 covers the outer peripheral surface of the column portion 1092 of the conductive layer 109, that is, the barrier portion 1081 is located between the column portion 1092 and the filling material layer 107 to separate the column portion 1092 and the filling material layer 107 from each other, so that the column portion 1092 does not contact the filling material layer 107.

[0040] According to the structure of the present application, the build-up material layer 108 is arranged on the hole wall of each first hole V1 (i.e. the inner wall surface of the filling material layer 107), the hole wall of each first hole V1 is covered by the build-up material layer 108, when the second hole V2 is formed by laser drilling, the laser only ablates the single material of the build-up material layer 108, and the laser ablation path does not involve the interface of different materials, so that the stepped structure is not generated. Therefore, each second hole V2 of the present application is located inside each first hole V1, the filling material layer 107 is not exposed to each second hole V2, the conductive layer 109 extends along each second hole V2 in the build-up material layer 108 to connect the electrode 1061 of the electronic component 106, the path of each second hole V2 of the present application does not involve the connection interface of different materials and does not generate the stepped structure, so that the hole wall of each second hole V2 can form a smooth and uniform surface, the column portion 1092 of the conductive layer 109 smoothly extends along each second hole V2 to connect the electrode 1061 of the electronic component 106, and the quality and reliability of the structure and electrical connection are ensured.

Claims

1. A circuit board having an embedded component, characterized by, The circuit board comprises: a substrate unit, comprising a substrate body, a filling material layer and an electronic component, the substrate body having a receiving space, the filling material layer being arranged in the receiving space, the electronic component being embedded in the filling material layer, the filling material layer being formed with at least one first hole extending from a surface of the filling material layer to at least one electrode of the electronic component; a build-up material layer arranged on a surface of the substrate unit and a hole wall of the at least one first hole and having at least one second hole inside the at least one first hole, the at least one second hole extending from a surface of the build-up material layer to the at least one electrode of the electronic component; and a conductive layer arranged on a surface of the build-up material layer and extending along the at least one second hole to connect the at least one electrode of the electronic component. A hole diameter of the at least one first hole is tapered inwardly from the surface of the filling material layer.

2. The circuit board with a built-in element according to Claim 1, wherein A hole diameter of the at least one second hole is tapered inwardly from the surface of the build-up material layer.

3. The circuit board with a built-in element according to Claim 1, wherein A portion of the conductive layer in each of the second holes is defined as a column portion, and a portion of the build-up material layer on the hole wall of each of the first holes is defined as a barrier portion, the barrier portion covering an outer circumferential surface of the column portion and being located between the column portion and the filling material layer.

4. The circuit board with a built-in element according to Claim 1, wherein Glass powder density and glass powder particle diameter of the filling material layer are different from glass powder density and glass powder particle diameter of the build-up material layer.

5. The circuit board with a built-in element according to Claim 1, wherein The circuit board is a core board in a multi-layer circuit board.

6. The circuit board with a built-in element according to Claim 1, wherein ​

Images