Circuit board assembly and fabricating method of the same

Abstract

A circuit board assembly and a fabricating method of the same are provided. The circuit board assembly includes a core insulation layer, an outer wiring layer, a thermal dissipation base, an electronic component, and a shielding and heat conducting structure. The thermal dissipation base is located between the core insulation layer and the outer wiring layer and has a mounting surface. The electronic component is disposed on the mounting surface. The shielding and heat conducting structure is located between the core insulation layer and the outer wiring layer, and is connected to the mounting surface and the outer wiring layer by surrounding the electronic component. A vertical projection area of the mounting surface is larger than a vertical projection area of the electronic component and the shielding and heat conducting structure.

Description

Technical Field

[0001] This application relates to a circuit board assembly and a method for manufacturing the same. Prior Technology

[0002] In recent years, electronic products have trended towards multifunctionality, high circuit density, and miniaturization, with circuit board technology evolving to embed electronic components within the board itself. However, with the increasing density of embedded electronic components, the demand for interference immunity between these components has also increased. Furthermore, after electronic components are embedded inside the circuit board, heat is concentrated within the board, so the heat dissipation requirements of the circuit board also need to be considered. Summary of the Invention

[0003] At least one embodiment of this application provides a circuit board assembly and a method for manufacturing the same, wherein the circuit board assembly utilizes a shielded thermally conductive structure to improve electromagnetic interference and enhance heat dissipation of electronic components embedded in the circuit board.

[0004] At least one embodiment of this application provides a circuit board assembly comprising a core insulating layer, a first outer circuit layer, a first heat sink, a first electronic component, and a first thermally conductive shielding structure. The first outer circuit layer is spaced apart from the core insulating layer. The first heat sink is located between the core insulating layer and the first outer circuit layer and has a mounting surface. The first electronic component is located between the core insulating layer and the first outer circuit layer and is mounted on the mounting surface. The first thermally conductive shielding structure is located between the core insulating layer and the first outer circuit layer and connects the mounting surface and the first outer circuit layer. The first thermally conductive shielding structure surrounds the first electronic component and has a connecting portion connecting the mounting surface. The vertical projection area of ​​the mounting surface is larger than the vertical projection areas of the first electronic component and the connecting portion.

[0005] The method for manufacturing a circuit board assembly provided in at least one embodiment of this application includes: providing a first substrate, wherein the first substrate includes a core insulating layer and a first metal layer; disposing a photosensitive layer on the first metal layer; forming a through-hole in the photosensitive layer, wherein a portion of the first metal layer is exposed at the bottom of the through-hole; forming a heat sink in the through-hole; after forming the heat sink, removing the photosensitive layer and the portion of the first metal layer not formed with the heat sink; disposing an electronic component on the mounting surface of the heat sink; providing a second substrate, wherein the second substrate includes a second metal layer; bonding the first substrate and the second substrate, wherein the electronic component is located between the heat sink and the second metal layer, and the second metal layer is exposed on both the first substrate and the second substrate; forming a thermally conductive shielding structure between the heat sink and the second metal layer, wherein the thermally conductive shielding structure connects the heat sink and the second metal layer and surrounds the electronic component; and patterning the second metal layer to form an outer circuit layer.

[0006] Based on the above, in the circuit board assembly disclosed in the above embodiments, the heat-conducting shielding structure surrounds the electronic components, thereby shielding electromagnetic interference between the electronic components and improving the heat dissipation capacity of the electronic components. Simple Explanation of the Diagram

[0007] To gain a more complete understanding of the embodiments and their advantages, the following description, taken in conjunction with the accompanying drawings, is provided, wherein: [Figure 1] is a partial top view of a circuit board assembly according to at least one embodiment of this application; [Figure 2] is a schematic cross-sectional view along section line I-I' in Figure 1; [Figure 3] is a partial cross-sectional view of the steps of providing a substrate and setting a photosensitive layer in the manufacturing method of the circuit board assembly of Figure 2; [Figure 4] is a partial cross-sectional view of the step of forming through holes in the manufacturing method of the circuit board assembly of Figure 2; [Figure 5] is a partial cross-sectional schematic diagram of the steps in the manufacturing method of the circuit board assembly of Figure 2, which involves forming the heat sink and the inner circuit layer; [Figure 6] is a partial cross-sectional view of the steps of setting the photosensitive layer and forming the heat sink in the manufacturing method of the circuit board assembly of Figure 2; [Figure 7] is a partial cross-sectional view of the step of removing the photosensitive layer and part of the metal layer in the manufacturing method of the circuit board assembly of Figure 2; [Figure 8] is a partial cross-sectional view of the step of bonding the substrate and forming the inner circuit layer in the manufacturing method of the circuit board assembly of Figure 2; [Figure 9] is a partial cross-sectional view of the step of forming a groove and setting electronic components in the manufacturing method of the circuit board assembly of Figure 2; [Figure 10] is a partial cross-sectional view of the substrate bonding step in the manufacturing method of the circuit board assembly of Figure 2; and [Figure 11] is a partial cross-sectional schematic diagram of the steps in the manufacturing method of the circuit board assembly of Figure 2, namely forming a shielding heat-conducting structure, a conductive structure and a patterned metal layer. Implementation

[0008] In the following text, to clearly present the technical features of this application, the dimensions (e.g., length, width, thickness, and depth) of the elements (e.g., layers, films, substrates, and regions) in the drawings will be enlarged proportionally, and the number of some elements may be reduced. Therefore, the description and explanation of the embodiments below are not limited to the number of elements in the drawings or the size and shape of the elements, but should cover the size, shape, and deviations from both caused by actual manufacturing processes and / or tolerances. For example, a flat surface shown in the drawings may have rough and / or non-linear characteristics, and an acute angle shown in the drawings may be rounded. Therefore, the elements presented in the drawings of this application are mainly for illustration and are not intended to accurately depict the actual shape of the elements, nor are they intended to limit the scope of the claims in this application.

[0009] Secondly, the terms "approximately," "approximately," or "substantially" used in this document not only cover explicitly stated numerical values ​​and ranges, but also the permissible deviation range understood by someone skilled in the art to which this invention pertains. This deviation range can be determined by errors that occur during measurement, such as those arising from limitations of the measurement system or process conditions. Furthermore, "approximately" can indicate a deviation within one or more standard deviations of the aforementioned numerical values, such as ±30%, ±20%, ±10%, or ±5%. The terms "approximately," "approximately," or "substantially" used in this document can be chosen based on optical, etching, mechanical, or other properties to select an acceptable deviation range or standard deviation, and are not applied to all optical, etching, mechanical, and other properties using a single standard deviation. Additionally, for clarity in the following embodiments, components with the same or similar functions are indicated by the same designation.

[0010] Figure 1 is a partial top view of a circuit board assembly 100 according to at least one embodiment of this application, and Figure 2 is a cross-sectional view along section line I-I' in Figure 1. Referring to Figures 1 and 2, the circuit board assembly 100 includes two outer circuit layers 111 and 112, multiple inner circuit layers 113-116, multiple dielectric layers 121-124, a core insulating layer 125, two protective layers 131 and 132, multiple heat sinks 210, 220, and 230, multiple electronic components 310, 320, and 330, multiple thermally conductive adhesive layers 410, 420, and 430, multiple shielding and thermally conductive structures 510, 520, and 530, and multiple conductive structures 610, 620, and 630. It should be noted that the protective layer 131 is not shown in Figure 1 to clearly show the outer circuit layer 111 and the shielding and thermally conductive structures 510 and 520. The circuit board assembly 100 can be used in electronic devices that use high-density embedded electronic components, but is not limited thereto.

[0011] In the examples of Figures 1 and 2, the circuit board assembly 100 includes four inner circuit layers 113-116, four dielectric layers 121-124, three heat sinks 210, 220, and 230, three electronic components 310, 320, and 330, three thermally conductive adhesive layers 410, 420, and 430, and three thermally shielding structures 510, 520, and 530. In some other embodiments, the circuit board assembly 100 may include only two inner circuit layers 114 and 115, or more than four inner circuit layers.

[0012] The outer circuit layers 111 and 112, the inner circuit layers 113-116, the dielectric layers 121-124, and the core insulating layer 125 are stacked. The outer circuit layers 111 and 112 and the inner circuit layers 113-116 may be made of copper. Further, the outer circuit layer 111 includes a ground portion 111a and a signal portion 111b spaced apart from each other. The outer circuit layer 112 includes a ground portion 112a and a signal portion 112b spaced apart from each other.

[0013] Dielectric layer 121 is sandwiched between outer circuit layer 111 and inner circuit layer 113. Dielectric layer 122 is sandwiched between inner circuit layers 113 and 114. Core insulating layer 125 is sandwiched between inner circuit layers 114 and 115. Dielectric layer 123 is sandwiched between inner circuit layers 115 and 116. Dielectric layer 124 is sandwiched between inner circuit layer 116 and outer circuit layer 112. In other words, core insulating layer 125 is located between outer circuit layers 111 and 112, and is spaced apart from outer circuit layers 111 and 112. The materials of dielectric layers 121-124 and core insulating layer 125 can be polyimide (PI), modified polyimide (MPI), liquid crystal polymer (LCP), or polytetrafluoroethylene (PTFE). The materials of dielectric layers 121-124, or the materials of dielectric layers 121-124 and core insulating layer 125, can be the same or different from each other, without limitation.

[0014] Protective layers 131 and 132 cover the outer circuit layer 111, dielectric layer 121, and outer circuit layer 112 and dielectric layer 124, respectively, and expose the ground portions 111a and 112a and the signal portions 111b and 112b of the outer circuit layers 111 and 112 for external electrical connections (not shown). Furthermore, the exposed surfaces of the outer circuit layers 111 and 112 from the protective layers 131 and 132 can be treated to form a surface finish layer (not shown). The surface finish layer can be a nickel plating layer or a gold plating layer.

[0015] Heat sinks 210 and 220 are adjacent to each other, while heat sinks 210 and 230 are opposite each other. Specifically, heat sinks 210 and 220 are disposed on the upper surface of the core insulating layer 125, located between the core insulating layer 125 and the outer circuit layer 111, and separated from each other by a dielectric layer 121. Heat sink 230 is disposed on the lower surface of the core insulating layer 125, located between the core insulating layer 125 and the outer circuit layer 112. In other words, heat sinks 210 and 220 are located on the same side of the core insulating layer 125, while heat sinks 210, 220, and 230 are located on opposite sides of the core insulating layer 125. Heat sinks 210, 220, and 230 can be thick copper plates.

[0016] Furthermore, heat sinks 210, 220, and 230 each have mounting surfaces 211, 221, and 231. The sides of heat sinks 210, 220, and 230 can extend along direction Z (the normal direction of the core insulating layer 125) or extend obliquely relative to direction Z. For example, the width of heat sinks 210, 220, and 230 along the I-I' section line can remain the same, or be a gradually widening step, or a gradually narrowing step, without limitation. Electronic components 310 and 320 are located between the core insulating layer 125 and the outer circuit layer 111, and are respectively mounted on mounting surfaces 211 and 221. Electronic component 330 is located between the core insulating layer 125 and the outer circuit layer 112, and is mounted on mounting surface 231. In other words, heat sinks 210 and 230 are located between electronic components 310 and 330.

[0017] Thermally conductive adhesive layers 410, 420, and 430 are located between electronic components 310, 320, and 330 and heat sinks 210, 220, and 230, respectively, and are used to conduct heat generated by electronic components 310, 320, and 330 to heat sinks 210, 220, and 230. Thermally conductive adhesive layers 410, 420, and 430 can be thermally conductive adhesives to bond electronic components 310, 320, and 330 and heat sinks 210, 220, and 230 together, and to conduct heat generated by electronic components 310, 320, and 330 to heat sinks 210, 220, and 230. Furthermore, in the examples of Figures 1 and 2, the surfaces and surrounding areas of electronic components 310, 320, and 330 are covered and filled by dielectric layers 121 and 124. In some other embodiments, the surfaces and surrounding areas of electronic components 310, 320, 330 may be covered and filled with adhesives, resins or other insulating materials, and then covered with dielectric layers 121, 124, thereby preventing the dielectric layers 121, 124 from denting in the areas where they are bonded to electronic components 310, 320, 330.

[0018] The heat-conducting shielding structures 510 and 520 are located between the core insulating layer 125 and the outer circuit layer 111, and are spaced apart from each other via dielectric layers 121 and 122. The heat-conducting shielding structure 530 is located between the core insulating layer 125 and the outer circuit layer 112. The heat-conducting shielding structures 510, 520, and 530 respectively surround the electronic components 310, 320, and 330, and connect the mounting surfaces 211, 221, and 231 to the ground portions 111a and 112a of the outer circuit layers 111 and 112. The material of the heat-conducting shielding structures 510, 520, and 530 may be copper. In some other embodiments, the material of the heat-conducting shielding structures 510, 520, and 530 may also be conductive resin, thermally conductive resin, or conductive paste. The shielding heat conduction structures 510, 520, and 530 can shield the electromagnetic interference between electronic components 310, 320, and 330, and at the same time conduct the heat energy of the heat sinks 210, 220, and 230 to the grounding parts 111a and 112a of the outer circuit layers 111 and 112, thereby improving the heat dissipation speed and heat dissipation capacity of the heat sinks 210, 220, and 230.

[0019] Specifically, the heat-conducting shielding structures 510, 520, and 530 each have connecting portions 511, 521, and 531 that connect to the mounting surfaces 211, 221, and 231. That is, the vertical projection areas of the mounting surfaces 211, 221, and 231 are larger than the vertical projection areas of the electronic components 310, 320, and 330 and the connecting portions 511, 521, and 531. In other words, in addition to providing space for the electronic components 310, 320, and 330, the mounting surfaces 211, 221, and 231 also reserve space for the connecting portions 511, 521, and 531.

[0020] Multiple conductive structures 610 and 620 may be located between the core insulating layer 125 and the outer circuit layer 111, and are spaced apart from each other. Multiple conductive structures 630 may be located between the core insulating layer 125 and the outer circuit layer 112, and are spaced apart from each other. The multiple conductive structures 610, 620, and 630 are used to transmit electronic signals between the outer circuit layers 111 and 112, the inner circuit layers 113-116, and the electronic components 310, 320, and 330. Conductive structures 610 and 620 may be electrically connected to the signal section 111b of the outer circuit layer 111 and the electrodes of the electronic components 310 and 320, respectively. Conductive structure 630 may be electrically connected to the signal section 112b of the outer circuit layer 112 and the electrodes of the electronic component 330. In some other embodiments, conductive structures 610 and 620 may be electrically connected to outer circuit layer 111 and inner circuit layer 113 or 114, while conductive structure 630 may be electrically connected to outer circuit layer 112 and inner circuit layer 115 or 116.

[0021] Furthermore, the heat-conducting shielding structure 510 includes a plurality of pillars 512. These pillars 512 are spaced apart around the electronic component 310. Therefore, other traces electrically connected to the electronic component 310 (e.g., signal section 111b shown in FIG. 1) can pass through the gaps between the pillars 512. The heat-conducting shielding structure 520 is a surrounding wall 523 having a plurality of notches 522. Similarly, other traces electrically connected to the electronic component 320 (e.g., signal section 111b shown in FIG. 1) can also pass through the notches 522. The heat-conducting shielding structure 530 may include a plurality of pillars or a surrounding wall having a plurality of notches, without limitation.

[0022] In some other embodiments, the inner circuit layers 113 and 116 also include ground and signal portions spaced apart from each other. The ground portions may be an annular copper sheet surrounding the electronic components 310, 320, and 330 in the Z direction, or multiple spaced copper sheets surrounding the electronic components 310, 320, and 330 in the Z direction (these spaced copper sheets may form annular copper sheets with notches). Some of these heat-conducting shielding structures surround the electronic components 310, 320, and 330 and connect the mounting surfaces 211, 221, and 231 to the ground portions of the inner circuit layers 113 and 116, while other heat-conducting shielding structures connect the ground portions of the inner circuit layers 113 and 116 to the ground portions 111a and 112a of the outer circuit layers 111 and 112.

[0023] Therefore, some of these shielding thermal conductive structures can shield electromagnetic interference between electronic components 310, 320, and 330, and simultaneously conduct heat energy from heat sinks 210, 220, and 230 to the ground portions of inner circuit layers 113 and 116. Other shielding thermal conductive structures can also shield electromagnetic interference between electronic components 310, 320, and 330, and conduct heat energy from the ground portions of inner circuit layers 113 and 116 to the ground portions 111a and 112a of outer circuit layers 111 and 112. In this way, the circuit board assembly 100 can also avoid electromagnetic interference between the embedded electronic components 310, 320, and 330, and can help the embedded electronic components 310, 320, and 330 easily dissipate the heat generated during operation. Furthermore, due to the reduced length of these shielding thermal conductive structures, the manufacturing process capability required to manufacture them can be reduced.

[0024] As described above, in the circuit board assembly 100, the shielding heat-conducting structures 510, 520, and 530 surround the electronic components 310, 320, and 330, thereby shielding the electromagnetic interference between the electronic components 310, 320, and 330. On the other hand, the heat generated by the electronic components 310, 320, and 330 can be transferred from the back of the electronic components 310, 320, and 330 to the thermally conductive adhesive layers 410, 420, and 430, and then transferred to the heat sinks 210, 220, and 230 via the thermally conductive adhesive layers 410, 420, and 430. The heat on the heat sinks 210, 220, and 230 is also conducted through the shielding heat-conducting structures 510, 520, and 530 to the ground portions 111a and 112a of the outer circuit layers 111 and 112, thereby dissipating into the air to achieve a good heat dissipation effect.

[0025] Furthermore, electronic components 310, 320, 330 and heat sinks 210, 220, 230 are separated by a core insulating layer 125 or dielectric layers 121, 122, preventing heat accumulation on the electronic components 310, 320, 330 and heat sinks 210, 220, 230, and ensuring that they do not interfere with each other. In other words, each electronic component 310, 320, 330 has its own heat dissipation path and will not affect the others.

[0026] Next, the manufacturing method of the circuit board assembly 100 of Figures 1 and 2 is described below. Figure 3 is a partial cross-sectional schematic diagram of the steps of providing a substrate 710 and setting photosensitive layers 720 and 730 in the manufacturing method of the circuit board assembly 100 of Figure 2. Referring to Figure 3, firstly, a substrate 710 is provided, wherein the substrate 710 includes a core insulating layer 125 and metal layers 711 and 712, which are respectively disposed on the upper and lower sides of the core insulating layer 125. The substrate 710 may be a double-sided copper-clad laminate. Next, photosensitive layers 720 and 730 are respectively disposed on the metal layers 711 and 712. The photosensitive layers 720 and 730 may be formed by printing photoresist material (e.g., photosensitive resin) or by laminating dry film photoresist material.

[0027] Figure 4 is a partial cross-sectional view of the step of forming vias 721, 722, 723, 731, and 732 in the manufacturing method of the circuit board assembly 100 of Figure 2. Referring to Figures 2, 3, and 4, multiple vias 721, 722, 723, 731, and 732 are formed in the photosensitive layers 720 and 730, respectively, wherein the bottom of the vias 721, 722, 723, 731, and 732 exposes portions of the metal layers 711 and 712, respectively. The vias 721, 722, and 731 correspond to the areas where heat sinks 210, 220, and 230 are subsequently formed, respectively, while the vias 723 and 732 correspond to the areas where inner circuit layers 114 and 115 are subsequently formed, respectively. The vias 721, 722, 723, 731, and 732 can be formed using a photolithography process.

[0028] Figure 5 is a partial cross-sectional view of the steps in the manufacturing method of the circuit board assembly 100 of Figure 2, showing the formation of partial heat sinks 210, 220, 230 and inner circuit layers 114, 115. Referring to Figures 4 and 5, metal layers 713 and 714 are formed in vias 721, 722, 723, 731, and 732, respectively. Metal layers 713 and 714 can be formed by selective electroplating. Metal layers 711 and 713 in vias 721 and 722 form partial heat sinks 210 and 220, and metal layers 712 and 714 in via 731 form partial heat sink 230. Metal layers 711 and 713 in via 723 form inner circuit layer 114, and metal layers 712 and 714 in via 732 form inner circuit layer 115.

[0029] Figure 6 is a partial cross-sectional view of the steps of setting photosensitive layers 740 and 750 and forming heat sinks 210, 220, and 230 in the manufacturing method of the circuit board assembly 100 of Figure 2. Referring to Figures 5 and 6, firstly, photosensitive layers 740 and 750 are set on metal layers 713 and 714 and photosensitive layers 720 and 730, respectively. Next, multiple through holes 721, 722, and 731 (corresponding to the positions of heat sinks 210, 220, and 230) are formed in the photosensitive layers 740 and 750 to expose portions of the heat sinks 210, 220, and 230. Next, metal layers 715 and 716 are formed in the through holes 721, 722, and 731, respectively, so that the metal layers 715 and 716 in the through holes 721, 722, and 731 form portions of the heat sinks 210, 220, and 230. It should be noted that the steps in Figure 6 can be repeated multiple times until the heat sinks 210, 220, and 230 reach a suitable thickness. Furthermore, since the heat sinks 210, 220, and 230 can be stacked layer by layer using a high-precision electroplating process, the width of the heat sinks 210, 220, and 230 can remain the same, or be in a gradually widening or gradually narrowing stepped shape, without any limitation.

[0030] Figure 7 is a partial cross-sectional view of the step of removing photosensitive layers 720, 730, 740, 750 and partial metal layers 711, 712 in the manufacturing method of the circuit board assembly 100 of Figure 2. Referring to Figures 6 and 7, after the heat sinks 210, 220, 230 are formed, the photosensitive layers 720, 730, 740, 750, and the partial metal layers 711, 712, where the heat sinks 210, 220, 230 and inner circuit layers 114, 115 are not formed, are removed. The photosensitive layers 720, 730, 740, 750 and the partial metal layers 711, 712 can be removed using laser or lithography processes.

[0031] Figure 8 is a partial cross-sectional view of the step of bonding substrates 710, 810, and 820 and forming inner circuit layers 113 and 116 in the manufacturing method of the circuit board assembly 100 of Figure 2. Referring to Figures 7 and 8, firstly, substrates 810 and 820 are provided, wherein substrate 810 includes a dielectric layer 122 and a metal layer 811, and substrate 820 includes a dielectric layer 123 and a metal layer 821. Substrates 810 and 820 may be single-sided copper-clad laminates. Next, substrates 710, 810, and 820 are bonded, wherein the dielectric layers 122 and 123 of substrates 810 and 820 respectively cover heat sinks 210, 220, and 230 and inner circuit layers 114 and 115. Substrates 710, 810, and 820 may be bonded by thermoforming. Next, metal layers 811 and 821 are patterned to form inner circuit layers 113 and 116, respectively. The patterned metal layers 811 and 821 can be fabricated using lithography and etching processes.

[0032] In the example of Figure 8, inner circuit layers 113 and 116 only contain signal sections. In some other embodiments, inner circuit layers 113 and 116 also include ground sections spaced apart from the signal sections, and these signal sections partially overlap with heat sinks 210, 220, and 230 in the Z direction. Furthermore, the ground sections can be annular copper sheets surrounding heat sinks 210, 220, and 230 in the Z direction, or multiple spaced copper sheets surrounding heat sinks 210, 220, and 230 in the Z direction. Next, multiple shielding thermally conductive structures are formed to connect the heat sinks 210, 220, and 230 and the ground sections of inner circuit layers 113 and 116. In some other embodiments, substrate 810 may only have dielectric layer 122 without metal layer 811, and substrate 820 may only have dielectric layer 123 without metal layer 821. Therefore, circuit board assembly 100 may not have inner circuit layers 113 and 116.

[0033] Figure 9 is a partial cross-sectional view of the steps in the manufacturing method of the circuit board assembly 100 of Figure 2, specifically the steps of forming recesses 812, 813, and 822 and setting electronic components 310, 320, and 330. Referring to Figures 8 and 9, firstly, recesses 812, 813, and 822 are formed in dielectric layers 122 and 123, respectively. The bottom of recesses 812, 813, and 822 exposes the mounting surfaces 211, 221, and 231 of the heat sinks 210, 220, and 230. That is, the openings of recesses 812, 813, and 822 are smaller than the area of ​​mounting surfaces 211, 221, and 231. Recesses 812, 813, and 822 can be formed using a laser. Because the openings of the grooves 812, 813, and 822 are smaller than the mounting surfaces 211, 221, and 231, the heat sinks 210, 220, and 230 can prevent the laser process forming the grooves 812, 813, and 822 from damaging the core insulating layer 125. Next, electronic components 310, 320, and 330 are respectively mounted on the mounting surfaces 211, 221, and 231 within the grooves 812, 813, and 822. The electronic components 310, 320, and 330 can be fixed to the heat sinks 210, 220, and 230 via thermally conductive adhesive layers 410, 420, and 430.

[0034] Figure 10 is a partial cross-sectional view of the step of bonding substrates 710, 810, 820, 910, and 920 in the manufacturing method of the circuit board assembly 100 of Figure 2. Referring to Figures 9 and 10, firstly, substrates 910 and 920 are provided, wherein substrate 910 includes a dielectric layer 121 and a metal layer 911, and substrate 920 includes a dielectric layer 124 and a metal layer 921. Substrates 910 and 920 may be single-sided copper-clad laminates. Next, substrates 710, 810, 820, 910, and 920 are bonded, wherein electronic components 310 and 320 are located between heat sinks 210 and 220 and metal layer 911, respectively, and electronic component 330 is located between heat sink 230 and metal layer 921. The dielectric layers 121 and 124 of substrates 910 and 920 cover electronic components 310, 320, and 330 and fill grooves 812, 813, and 822, respectively. Substrates 710, 810, 820, 910, and 920 can be bonded together using a thermo-pressing method.

[0035] In some other implementations, before bonding substrates 710, 810, 820, 910, 920, electronic components 310, 320, 330 can be covered with adhesives, resins or other insulating materials and grooves 812, 813, 822 can be filled, thereby preventing the bonding dielectric layers 121, 124 from being recessed in grooves 812, 813, 822.

[0036] Figure 11 is a partial cross-sectional view of the steps in the manufacturing method of the circuit board assembly 100 of Figure 2, specifically the steps of forming the shielding heat-conducting structures 510, 520, 530, the conductive structures 610, 620, 630, and the patterned metal layers 911, 921. Referring to Figures 10 and 11, multiple through-holes or trenches (not shown) are formed between the heat sinks 210, 220, 230, the dielectric layers 121, 122, 123, 124, and the metal layers 911, 921, respectively, where the through-holes or trenches expose the mounting surfaces 211, 221, 231 of the heat sinks 210, 220, 230. The through-holes or trenches can be formed using laser technology. The heat sinks 210, 220, 230 can also avoid damage to the core insulating layer 125 during the laser process of forming the through-holes or trenches. Next, multiple heat-conducting shielding structures 510, 520, and 530 are formed within the through holes or trenches. These structures connect the mounting surfaces 211, 221, and 231 of the heat sinks 210, 220, and 230 to the metal layers 911 and 921, and surround the electronic components 310, 320, and 330. The heat-conducting shielding structures 510, 520, and 530 can be formed by filling with conductive resin, thermally conductive resin, or conductive paste, or by electroplating.

[0037] In some other embodiments, multiple vias or trenches (not shown) may be formed between the ground portions (not shown) of the inner circuit layers 113, 116, the dielectric layers 121, 124, and the metal layers 911, 921, whereby the vias or trenches expose the ground portions of the inner circuit layers 113, 116. Then, multiple shielding heat-conducting structures are formed within the vias or trenches, connecting the ground portions of the inner circuit layers 113, 116 and the metal layers 911, 921. These shielding heat-conducting structures can cooperate with the aforementioned shielding heat-conducting structures formed between the heat sinks 210, 220, 230 and the ground portions of the inner circuit layers 113, 116, achieving the effect of shielding electromagnetic interference between electronic components 310, 320, 330, while simultaneously conducting heat energy from the heat sinks 210, 220, 230 to the metal layers 911, 921.

[0038] On the other hand, multiple vias (not shown) are formed between electronic components 310, 320, and 330, dielectric layers 121 and 124, and metal layers 911 and 921, respectively, exposing the electrodes of electronic components 310, 320, and 330. These vias can also be formed using laser technology. Next, multiple conductive structures 610, 620, and 630 are formed within the vias, connecting the electrodes of electronic components 310, 320, and 330 to metal layers 911 and 921. The conductive structures 610, 620, and 630 can be formed using electroplating.

[0039] Next, patterned metal layers 911 and 921 are used to form outer circuit layers 111 and 112, respectively. The ground portions 111a and 112a and the signal portions 111b and 112b of the outer circuit layers 111 and 112 are connected to the shielding heat-conducting structures 510, 520, and 530 and the conductive structures 610, 620, and 630, respectively. The patterned metal layers 911 and 921 can be fabricated using lithography and etching processes. Next, as shown in FIG2, protective layers 131 and 132 are formed on the outer circuit layers 111 and 121, and on the outer circuit layers 112 and 124, respectively. Next, a surface treatment layer (not shown) is formed on the exposed surfaces of the outer circuit layers 111 and 112 from the protective layers 131 and 132. Thus, the fabrication of the circuit board assembly 100 is essentially completed.

[0040] In summary, in the circuit board assembly 100 disclosed in the above embodiments, the shielding heat-conducting structures 510, 520, and 530 surround the electronic components 310, 320, and 330, thereby shielding the electromagnetic interference between the electronic components 310, 320, and 330. Furthermore, the shielding heat-conducting structures 510, 520, and 530 are connected to the heat sinks 210, 220, and 230 and the ground portions 111a and 112a of the outer circuit layers 111 and 112, thereby improving the heat dissipation capacity of the electronic components 310, 320, and 330. In addition, the use of thermally conductive adhesive layers 410, 420, and 430 between the heat sinks 210, 220, and 230 and the electronic components 310, 320, and 330 not only fixes the heat sinks 210, 220, and 230 and the electronic components 310, 320, and 330, but also facilitates the conduction of heat generated by the electronic components 310, 320, and 330 to the heat sinks 210, 220, and 230.

[0041] Furthermore, the electronic components 310, 320, 330 and the heat sinks 210, 220, 230 are separated by the core insulating layer 125 or the dielectric layers 121, 122, 123, 124, so the heat generated by each electronic component 310, 320, 330 will not accumulate or affect each other. In addition, the area of ​​the mounting surfaces 211, 221, 231 of the heat sinks 210, 220, 230 is larger than the openings of the grooves 812, 813, 822 for the electronic components 310, 320, 330, which can prevent the laser process forming the grooves 812, 813, 822 from damaging the core insulating layer 125.

[0042] Although this application has been disclosed above with reference to embodiments, it is not intended to limit this application. Those skilled in the art to which this application pertains may make some modifications and refinements without departing from the spirit and scope of this application. Therefore, the scope of protection of this application shall be determined by the appended claims.

[0043] 100: Circuit board assembly 111, 112: Outer circuit layer 111a, 112a: Grounding part 111b, 112b: Signal section 113~116: Inner circuit layer 121~124: Dielectric layer 125: Core Insulation Layer 131, 132: Protective layer 210, 220, 230: Heatsink base 211,221,231: Setting the surface 310, 320, 330: Electronic components 410, 420, 430: Thermally conductive adhesive layer 510, 520, 530: Shielded thermal conductive structure 511, 521, 531: Connecting parts 512: Column 522: Gap 523: Surrounding Wall 610, 620, 630: Conductive structures 710,810,820,910,920:Substrate 711,712,713,714,715,716,811,821,911,921: Metal layer 720, 730, 740, 750: Photosensitive layer 721, 722, 723, 731, 732: Through holes 812, 813, 822: Groove Z: Direction

Claims

1. A circuit board assembly comprising: a core insulating layer; a first outer circuit layer spaced apart from the core insulating layer; a first heat sink located between the core insulating layer and the first outer circuit layer and having a mounting surface; a first electronic component located between the core insulating layer and the first outer circuit layer and disposed on the mounting surface; and a first thermally conductive shielding structure located between the core insulating layer and the first outer circuit layer and connecting the mounting surface and the first outer circuit layer, wherein the first thermally conductive shielding structure surrounds the first electronic component and has a connecting portion connecting the mounting surface, the vertical projection area of ​​the mounting surface is larger than the vertical projection area of ​​the first electronic component and the connecting portion, and the first thermally conductive shielding structure is a surrounding wall having at least one notch.

2. The circuit board assembly as claimed in claim 1, wherein the first thermally conductive shielding structure comprises a plurality of pillars spaced apart around the first electronic component.

3. The circuit board assembly as claimed in claim 1 further comprises: a thermally conductive adhesive layer disposed between the first heat sink and the first electronic component.

4. The circuit board assembly of claim 1, further comprising: a conductive structure located between the core insulating layer and the first outer circuit layer; wherein the first outer circuit layer includes a ground portion and a signal portion spaced apart from each other, the first thermally conductive shielding structure is connected to the ground portion, and the conductive structure is electrically connected to the first electronic component and the signal portion.

5. The circuit board assembly of claim 1, further comprising: a dielectric layer located between the core insulating layer and the first outer circuit layer; a second heat sink located between the core insulating layer and the first outer circuit layer, and spaced apart from the first heat sink via the dielectric layer; a second electronic component located between the core insulating layer and the first outer circuit layer, and disposed on the second heat sink; and a second thermally conductive shielding structure located between the core insulating layer and the first outer circuit layer, connecting the second heat sink and the first outer circuit layer, and surrounding the second electronic component.

6. The circuit board assembly of claim 1, further comprising: a second outer circuit layer spaced from the core insulating layer, wherein the core insulating layer is located between the first outer circuit layer and the second outer circuit layer; a third heat sink located between the core insulating layer and the second outer circuit layer; a third electronic component located between the core insulating layer and the second outer circuit layer and disposed on the third heat sink, wherein the first heat sink and the third heat sink are located between the first electronic component and the third electronic component; and a third thermally conductive shielding structure located between the core insulating layer and the second outer circuit layer, connecting the third heat sink and the second outer circuit layer, and surrounding the third electronic component.

7. A method of manufacturing a circuit board assembly, comprising: providing a first substrate, wherein the first substrate includes a core insulating layer and a first metal layer; disposing a photosensitive layer on the first metal layer; forming a through-hole in the photosensitive layer, wherein the bottom of the through-hole exposes a portion of the first metal layer; forming a heat sink in the through-hole; after forming the heat sink, removing the photosensitive layer and the portion of the first metal layer not formed with the heat sink; disposing an electronic component on a mounting surface of the heat sink; providing a second substrate, wherein the second substrate includes a second metal layer; combining the first substrate and the second substrate, wherein the electronic component is located between the heat sink and the second metal layer, and the second metal layer is exposed on the first substrate and the second substrate; forming a thermally conductive shielding structure between the heat sink and the second metal layer, wherein the thermally conductive shielding structure connects the heat sink and the second metal layer and surrounds the electronic component; and patterning the second metal layer to form an outer circuit layer.

8. A method of manufacturing a circuit board assembly as claimed in claim 7, further comprising: before setting the electronic component, bonding a first substrate and a third substrate, wherein the third substrate includes a first dielectric layer; and after bonding the first substrate and the third substrate, forming a groove in the first dielectric layer for setting the electronic component, wherein the bottom of the groove exposes a portion of the setting surface, and the opening of the groove is smaller than the area of ​​the setting surface.

9. The method of manufacturing a circuit board assembly as claimed in claim 7, further comprising: after bonding the first substrate and the second substrate, forming a conductive structure between the electronic component and the second metal layer, wherein the conductive structure electrically connects the electronic component and the second metal layer.

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