Circuit board and method of manufacturing the same

Abstract

A method of fabricating a circuit board includes forming a recess in a first circuit substrate, disposing an electronic component in the recess, and laminating a second circuit substrate to the first circuit substrate to form a third circuit substrate, wherein the electronic component is embedded in the third circuit substrate. The method further includes forming an opening in the third circuit substrate to expose the electronic component and an inner surface of the third circuit substrate. The method further includes disposing an insulating shell in the opening. The insulating shell has a first section surrounding and directly contacting the electronic component, a second section located beside the first section and facing the inner surface of the third circuit substrate, an inner wall between the first section and the second section, a first chamber surrounded by the first section and the inner wall, and a second chamber surrounded by the second section and the inner wall. The method further includes adding a heat exchange fluid into the first chamber. Thereby, the performance and reliability of the circuit are improved. A structure of a circuit board is also provided.

Description

Technical Field

[0001] This application relates to a circuit board and a method for manufacturing the same, particularly a circuit board with embedded electronic components and a method for manufacturing the same. Background Technology

[0002] As the development trend of electronic products has shifted towards speed, high reliability, multifunctionality, miniaturization, and high performance, the technology of embedding electronic components within circuit boards is gaining increasing favor in the industry. Embedding electronic components within circuit boards not only reduces wiring area but also shortens connection lengths, thus meeting the aforementioned development trends of electronic products.

[0003] Therefore, manufacturers are striving to improve the reliability and performance of circuit boards with embedded electronic components. Summary of the Invention

[0004] According to some embodiments of this application, a method for manufacturing a circuit board includes forming a groove in a first circuit substrate, disposing an electronic component in the groove, and pressing a second circuit substrate onto the first circuit substrate, such that the second circuit substrate and the first circuit substrate together form a third circuit base, wherein the electronic component is embedded in the third circuit substrate. The method for manufacturing the circuit board further includes forming an opening in the third circuit substrate, wherein the electronic component and the inner surface of the third circuit substrate are exposed in the opening. The method for manufacturing the circuit board further includes disposing an insulating shell in the opening, wherein the insulating shell has a first segment surrounding and directly contacting the electronic component, a second segment located beside the first segment and facing the inner surface of the third circuit substrate, an inner wall between the first segment and the second segment, a first chamber surrounded by the first segment and the inner wall, and a second chamber surrounded by the second segment and the inner wall. The method for manufacturing the circuit board further includes adding a heat exchange fluid to the first chamber.

[0005] In some embodiments, forming an opening in the third circuit substrate includes extending the opening from the upper surface of the third circuit substrate into the third circuit substrate, and the bottom of the opening is lower than the bottom opening of the electronic component.

[0006] In some embodiments, the distance between the bottom of the opening and the bottom of the electronic component is greater than 10 micrometers.

[0007] In some embodiments, forming an opening in the third circuit board includes exposing the upper and side surfaces of the electronic component in the opening. Providing an insulating shell in the opening includes allowing the first segment to directly contact the upper and side surfaces of the electronic component.

[0008] In some embodiments, the insulating shell includes an inner surface in the opening that allows the second segment to directly contact the third circuit board.

[0009] In some embodiments, setting an insulating shell in an opening includes setting an adhesive material between the insulating shell and the third circuit board, and attaching the insulating shell and the third circuit board together by means of the adhesive material.

[0010] In some embodiments, the method of manufacturing a circuit board further includes disposing a heat dissipation layer on an insulating shell, wherein the heat dissipation layer is in direct contact with the insulating shell.

[0011] In some embodiments, holes are formed in the insulating shell before the heat exchange fluid is added to the first chamber, through which the heat exchange fluid is added to the first chamber.

[0012] In some embodiments, providing a heat dissipation layer on the insulating shell includes covering the holes with the heat dissipation layer to seal the heat exchange fluid in the first chamber.

[0013] In some embodiments, forming an opening in the third circuit board includes removing a portion of an electronic component such that the side surface of the electronic component is vertical.

[0014] In some embodiments, the method of manufacturing a circuit board further includes disposing a heat sink on a third circuit board and disposing a heat dissipation layer on an insulating shell and a heat sink, wherein the heat sink directly contacts the insulating shell and the heat sink.

[0015] According to some embodiments of this application, a circuit board includes a circuit board substrate, electronic components embedded in the circuit board substrate, and an insulating shell embedded in the circuit board substrate and located between the circuit board substrate and the electronic components. The insulating shell includes a first segment, a second segment, an inner wall, a first chamber, and a second chamber, wherein the first segment surrounds and directly contacts the electronic components, the second segment is located beside the first segment and faces the inner surface of a third circuit board substrate, the inner wall is located between the first segment and the second segment, the first chamber is surrounded by the first segment and the inner wall, and the second chamber is surrounded by the second segment and the inner wall. The circuit board also includes a heat exchange fluid distributed in the first chamber.

[0016] In some embodiments, the insulating shell has an inverted U-shape in cross-section.

[0017] In some embodiments, the heat exchange fluid includes liquids and gases.

[0018] In some embodiments, the level of the heat exchange fluid is equal to or higher than the upper surface of the electronic component.

[0019] In some embodiments, air is present in the second chamber.

[0020] In some embodiments, the circuit board further includes a heat dissipation layer disposed on and in direct contact with the insulating shell.

[0021] In some embodiments, the circuit board further includes a heat sink disposed on the circuit board. The projection of the heat sink on the circuit board is offset from the projection of the electronic component on the circuit board. A heat dissipation layer is disposed on the heat sink and in direct contact with the heat sink.

[0022] In some embodiments, the electronic component is a capacitor and includes a first electrode, a second electrode disposed below the first electrode, and a dielectric layer disposed between the first electrode and the second electrode. The side surfaces of the first electrode, the second electrode, and the dielectric layer are coplanar with each other.

[0023] In some embodiments, the side surfaces of the first electrode, the second electrode, and the dielectric layer directly contact the first segment. The upper surface of the first electrode directly contacts the first segment. The lower surface of the second electrode directly contacts the circuit board.

[0024] Embodiments of this application provide a circuit board and a method for manufacturing the same. Electronic components and an insulating shell are embedded within the circuit board, and the insulating shell is disposed around the electronic components, wherein the insulating shell has several chambers. This improves the circuit's performance and reliability. Attached Figure Description

[0025] Please read the following embodiments in conjunction with the accompanying drawings for a clear understanding of the viewpoints of this application. It should be noted that, according to industry standard practice, the various features are not drawn to scale. In fact, for clarity of discussion, the dimensions of various features may be arbitrarily enlarged or reduced. Furthermore, the same reference numerals denote the same elements.

[0026] Figure 1 , Figure 2 and Figure 3A Cross-sectional views of the circuit board at various manufacturing stages are shown in some embodiments of this application.

[0027] Figure 3B The illustrations are based on some embodiments of this application. Figure 3A Partial top view Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 ,and Figure 9 Cross-sectional views of the circuit board at various manufacturing stages are shown in some embodiments of this application. Detailed Implementation

[0028] When an element, such as a layer, film, region, or substrate, is referred to as being "on" or "connected" to another element, it may be directly on or connected to the other element, or an intermediate element may also be present. Conversely, when an element is referred to as being "directly on" or "directly connected" to another element, no intermediate element is present. As used herein, "connection" can refer to a physical and / or electrical connection. Furthermore, "electrical connection" or "coupling" may refer to the presence of other elements between the two elements.

[0029] Furthermore, relative terms such as “down” or “bottom” and “up” or “top” may be used herein to describe the relationship between one element and another, as illustrated in the figures. It should be understood that relative terms are intended to include different orientations of the device beyond those shown in the figures. For example, if a device in one figure is flipped, an element described as being “down” to other elements will be oriented “up” to other elements. Thus, the exemplary term “down” can include both “down” and “up” orientations, depending on the specific orientation of the figure. Similarly, if a device in one figure is flipped, an element described as being “down” or “below” to other elements will be oriented “above” to other elements. Thus, the exemplary term “down” or “below” can include both “up” and “down” orientations.

[0030] As used herein, “about,” “approximately,” or “generally” includes the value and the average value within an acceptable range of deviations from a particular value as determined by one of ordinary skill in the art, taking into account the measurement in question and a particular number of errors associated with the measurement (i.e., limitations of the measurement system). For example, “about” may mean within one or more standard deviations of the value.

[0031] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains. It will be further understood that terms such as those defined in commonly used dictionaries should be interpreted as having the same meaning as they have in the context of the relevant art and this application, and will not be interpreted as having an idealized or overly formal meaning unless expressly defined as such herein.

[0032] As electronic products develop towards higher reliability, multifunctionality, miniaturization, and high performance, electronic product packaging technology has entered the high-density packaging stage. The application of embedding capacitors in circuit boards is becoming more and more widespread, which can reduce the space used by the circuit board and help to miniaturize the circuit board.

[0033] When a capacitor is embedded in a circuit board, the heat generated during operation can be dissipated through the heat sink on the circuit board, thus preventing excessive heat concentration in the capacitor and circuit board, which could cause the capacitor or other electronic components to overheat and affect the performance of the electronic product.

[0034] Furthermore, when capacitors are embedded in circuit boards, they may form parasitic capacitances with surrounding transmission lines or electronic components. These parasitic capacitances can cause RC delay, affecting the performance of electronic products. In particular, as circuit boards move towards higher frequencies, this parasitic capacitance phenomenon will become more pronounced.

[0035] Generally, a capacitor, such as a planar capacitor, may consist of two layers of metal (e.g., copper) and a dielectric material between them. The capacitance of the capacitor is proportional to the area of ​​the metal layers facing each other. Therefore, the manufacturing precision of the area of ​​the two metal layers facing each other in each capacitor is crucial to achieve consistency.

[0036] Therefore, this application provides a circuit board structure with embedded capacitors and a method for manufacturing the same, in order to improve heat dissipation efficiency, reduce parasitic capacitance, and improve the manufacturing accuracy of the capacitors, thereby improving the reliability of the capacitors and the circuit board.

[0037] It should be noted that, unless otherwise specified, the order in which these operations or events are described as a series of operations or events in the following embodiments should not be limited. For example, some operations or events may be performed in a different order than those described in this application, some operations or events may occur simultaneously, some operations or events may be unnecessary, and / or some operations or events may be repeated. Furthermore, the actual process may require additional operations before, during, or after each step to complete the circuit board formation. Therefore, this application may briefly describe some of these additional operations.

[0038] Please refer to Figure 1 , Figure 1 To illustrate a cross-sectional view of a circuit board at one of the manufacturing stages according to some embodiments of this application, firstly, an electronic component 100 is provided. The electronic component 100 may be a passive component, such as a capacitor, inductor, or resistor, but is not limited thereto.

[0039] In such Figure 1 In the illustrated embodiment, the electronic component 100 is a capacitor, such as a planar capacitor, which includes a first electrode 102, a second electrode 104 disposed on the first electrode 102, and a dielectric layer 106 disposed between the first electrode 102 and the second electrode 104. When the electronic component 100 is a planar capacitor, the planes of the first electrode 102 and the second electrode 104 are opposite to each other, and the dielectric layer 106 is sandwiched between the first electrode 102 and the second electrode 104.

[0040] The first electrode 102 and the second electrode 104 may be aligned with each other. In some embodiments, the sidewalls of the first electrode 102 and the second electrode 104 may be flush with each other. In other embodiments, the sidewalls of the first electrode 102 and the second electrode 104 may be offset and not flush with each other.

[0041] The material of the first electrode 102 may include a metal such as copper. The material of the second electrode 104 may include a metal such as copper. In some embodiments, the first electrode 102 and the second electrode 104 may be composed of the same material. The material of the dielectric layer 106 may be a dielectric material, such as silicon oxide, silicon nitride, aluminum oxide, titanium oxide, tantalum oxide, a dielectric material with a high dielectric constant, or other suitable dielectric materials.

[0042] Please refer to Figure 2 , Figure 2 The diagram illustrates a cross-sectional view of a circuit board at one of the manufacturing stages, according to some embodiments of this application. Next, a first circuit board 200 is provided, and a recess 210 is formed in the first circuit board 200. Subsequently, after forming the recess 210, an electronic component 100 is disposed in the recess 210. The recess 210 is larger than the electronic component 100, thus accommodating the electronic component 100.

[0043] The number of layers of the first circuit board 200 can be adjusted according to design requirements. The first circuit board 200 may have an insulating layer 202, a circuit layer 204, conductive blind vias (not shown), or pads (not shown). In some embodiments, the outermost layer of the first circuit board 200 may be a metal foil layer 206. In other embodiments, the metal foil layer 206 may be patterned to form the outermost circuit layer (not shown) or pads (not shown) of the first circuit board 200.

[0044] Methods for forming the groove 210 may include routing, mechanical or laser drilling, etching processes, other suitable techniques, or combinations thereof. The insulating layer 202 of the first circuit board 200 may include a dielectric material, which may be formed of a polymeric or non-polymeric material. Examples include liquid crystal polymer (LCP), bismaleimide-triazine (BT), prepreg, resins containing inorganic fillers (e.g., Ajinomoto Build-up Film, ABF), epoxy resin, polyimide (PI), or other resin materials, but this application is not limited to the examples listed above. In some embodiments, the insulating layer 202 of the first circuit board 200 may be formed of a photoimageable dielectric material or a photoactive dielectric material.

[0045] Next, a second circuit board 220 is provided. The second circuit board 220 is disposed on the first circuit board 200 and the electronic component 100. The second circuit board 220 can be combined with the first circuit board 200 in subsequent processes to package the electronic component 100.

[0046] The second circuit board 220 may have an insulating layer 222, a circuit layer (not shown), conductive blind vias (not shown), or pads (not shown). In some embodiments, the second circuit board 220 is a single-sided board, therefore the outermost layer of the second circuit board 220 may be a metal foil layer 226. It should be noted that, although Figure 2 The embodiments shown only depict a single layer of insulating layer 222 and metal foil layer 226, but the number of layers can be adjusted according to the actual process or product design, which is also within the scope of this application.

[0047] The insulating layer 222 of the second circuit board 220 may include a dielectric material, which may be formed of a polymer or a non-polymer. For example, it may be formed of liquid crystal polymer (LCP), bis(maleic)imide resin (BT), prepreg, resin containing inorganic fillers (e.g., ABF), epoxy resin, polyimide (PI), or other resin materials, but this application is not limited to the examples above. In some embodiments, the insulating layer 222 of the second circuit board 220 may be formed of a photoimaging dielectric material or a photosensitive dielectric material.

[0048] Please refer to Figure 3A , Figure 3AThe diagram illustrates a cross-sectional view of a circuit board at one of the manufacturing stages, according to some embodiments of this application. Next, a second circuit board 220 and a first circuit board 200 are laminated. The first circuit board 200 or the second circuit board 220 may have an adhesive material. In some embodiments, during the lamination of the first circuit board 200 and the second circuit board 220, the adhesive material is compressed and may be distributed in the grooves 210 (see reference). Figure 2 The adhesive material can be placed in the space between the first circuit board 200 and the electronic component 100, between the second circuit board 220 and the electronic component 100, between the first circuit board 200 and the second circuit board 220, or in other accommodating spaces. Furthermore, the adhesive material can be formed by the temperature during the lamination process. After the lamination process, the second circuit board 220 and the first circuit board 200 together form the third circuit board 300. The electronic component 100 can be embedded in the third circuit board 300. In some embodiments, the adhesive material can completely fill the groove 210 and contact (e.g., directly contact) the electronic component 100, so that the electronic component 100 can be fixed in the third circuit board 300.

[0049] After lamination, the metal foil layer 206 (see reference) can be applied. Figure 2 ) and metal foil layer 226 (please refer to Figure 2 A patterning process is performed to form the outermost circuit layer 302 of the third circuit board 300. Figure 3A In the illustrated embodiment, after the metal foil layer 226 is patterned, a portion of the metal foil layer 226 forms a circuit layer 302 to transmit electrical signals, while another portion of the metal foil layer 226 can form a heat sink 304, wherein the heat sink 304 is not used for transmitting electrical signals. Therefore, the heat sink 304 may be electrically isolated from other conductive elements.

[0050] Please refer to Figure 3B , Figure 3B The illustrations are based on some embodiments of this application. Figure 3A A partial top view is provided to illustrate the exemplary arrangement of the heat sink 304 and the electronic component 100. The heat sink 304 is disposed on the third circuit board 300, and the electronic component 100 is disposed within the third circuit board 300. The exemplary arrangement of the electronic component 100 within the third circuit board 300 is shown with broken lines. It should be noted that, for clarity, Figure 3B Only some components are drawn in a simplified manner, so Figure 3B (Top view) and Figure 3A The components in the (cross-section diagram) may not correspond perfectly.

[0051] In such Figure 3BIn the illustrated embodiment, the positions of the electronic component 100 and the heat sink 304 are separated from each other in the horizontal direction (e.g., separated from each other in the X-axis direction) to reduce the possibility of parasitic capacitance forming between the electronic component 100 and surrounding conductive elements (e.g., the heat sink 304 having a metallic material). In other words, the projection of the heat sink 304 on the third circuit board 300 is offset from the projection of the electronic component 100 on the third circuit board 300.

[0052] Please refer to Figure 4 , Figure 4 The diagram illustrates a cross-sectional view of a circuit board at one of the manufacturing stages, according to some embodiments of this application. Next, an opening 400 is formed in the third circuit board 300 to expose the electronic component 100 and the inner surface 300S1 of the third circuit board 300 within the opening 400. In some embodiments, the opening 400 exposes the side surface 100S of the electronic component 100. In some embodiments, the opening 400 exposes both the side surface 100S and the top surface 100T of the electronic component 100. In some embodiments, the opening 400 exposes the side surface 100S of the electronic component 100 but not the top surface 100T.

[0053] While forming the opening 400 in the third circuit board 300, a portion of the electronic component 100 may be removed to modify the morphology of the electronic component 100. For example, a portion of the first electrode 102, a portion of the second electrode 104, or a portion of the dielectric layer 106 may be removed. The modified electronic component 100 may have a vertical side surface 100S (e.g., a side surface extending along the Z-axis). In addition, the side surface 100S of the modified electronic component 100 may be parallel to the inner surface 300SI of the third circuit board 300.

[0054] When the electronic component 100 is a capacitor, the side surfaces of the first electrode 102, the second electrode 104, and the dielectric layer 106 are coplanar with each other. In this way, the sidewalls of the first electrode 102 and the second electrode 104 can be aligned with each other, so that the first electrode 102 can be aligned with the second electrode 104.

[0055] Therefore, the process method provided in this application, which involves first laminating the capacitor, then embedding the capacitor within the circuit board, and subsequently forming an opening in the circuit board to refine the capacitor's shape, helps improve the accuracy of the aligned area between the electrodes in the capacitor. As mentioned earlier, the capacitance performance of a capacitor is directly proportional to the size of the aligned area between its electrodes. Improving the accuracy of the aligned area between the electrodes enhances the consistency between individual capacitors, thus contributing to increased product reliability.

[0056] An opening 400 extends from the upper surface of the third circuit board 300 into the third circuit board 300, with the bottom of the opening 400 lower than the bottom of the electronic component 100. In an embodiment where the electronic component 100 is a capacitor, the bottom of the opening 400 is lower than the bottom of the second electrode 104. The distance D between the bottom of the opening 400 and the bottom of the electronic component 100 is equal to or greater than about 10 micrometers to remove the insulating layer 202 surrounding the electronic component 100. When the distance D is less than about 10 micrometers, the insulating layer 202 surrounding the electronic component 100 may not be completely removed, causing the portion of the insulating layer 202 sandwiched between the electronic component 100 and the circuit layer 204 to induce parasitic capacitance, thereby affecting the performance of the electronic component 100.

[0057] Methods for forming the opening 400 may include routing, mechanical or laser drilling, etching, other suitable techniques, or a combination thereof.

[0058] Please refer to Figure 5 , Figure 5 A cross-sectional view of a circuit board at one of the manufacturing stages is shown according to some embodiments of this application. In some embodiments, at the formation of opening 400 (see...) Figure 4 Afterwards, the third circuit board 300 may still cover the upper surface 100T of the electronic component 100, meaning that the opening 400 does not expose the upper surface 100T of the electronic component 100. Therefore, the third circuit board 300 located on the upper surface 100T of the electronic component 100 can be further removed, causing the opening 400 to expand into an opening 500. At this time, the opening 500 can expose the upper surface 100T of the electronic component 100, and therefore the opening 500 also exposes the side surface 100S of the electronic component 100 and the inner surface 300SI of the third circuit board 300. Figure 4 and Figure 5 In the illustrated embodiment, opening 500 is generally similar to opening 400, except that opening 500 additionally exposes the upper surface 100T of electronic component 100.

[0059] Methods for forming the opening 500 may include raking, mechanical or laser drilling, etching, peeling, other suitable techniques, or a combination of the above.

[0060] Please refer to Figure 6 , Figure 6 This diagram illustrates a cross-sectional view of a circuit board at one of the manufacturing stages, according to some embodiments of this application. Next, an insulating shell 600 is provided at the opening 500 (see reference...). Figure 5Specifically, the insulating shell 600 is disposed between the third circuit board 300 and the electronic component 100. The insulating shell 600 is positioned below the heat sink 304, for example, below the lower surface of the heat sink 304. In this way, the insulating shell 600 is embedded within the third circuit board 300.

[0061] The morphology of the insulating shell 600 is related to the arrangement between the third circuit board 300 and the electronic component 100. Figure 6 In the cross-sectional view shown, the insulating shell 600 is inverted U-shaped in this section to accommodate the arrangement between the third circuit board 300 and the electronic component 100.

[0062] The insulating shell 600 may include a first segment 602, a second segment 604, and an inner wall 606, wherein the first segment 602 surrounds and directly contacts the electronic component 100, the second segment 604 is located next to the first segment 602 and faces the inner surface 300SI of the third circuit board 300, and the inner wall 606 is located between the first segment 602 and the second segment 604. The insulating shell 600 may also include a third segment 608, wherein the third segment 608 is exposed in the third circuit board 300. The third segment 608 connects the first segment 602 and the second segment 604. The insulating shell 600 may also include a fourth segment 609, wherein the fourth segment 609 is located below the bottom of the electronic component 100. In some embodiments, the fourth segment 609 is adjacent to the opening 500 (see reference). Figure 5 The bottom of the fourth segment 609 connects the first segment 602 and the second segment 604.

[0063] In detail, when the opening is 500 (please refer to...) Figure 5 When the upper surface 100T and side surface 100S of the electronic component 100 are exposed, the first segment 602 of the insulating shell 600 directly contacts the upper surface 100T and side surface 100S of the electronic component 100. In some embodiments, the second segment 604 of the insulating shell 600 directly contacts the inner surface 300SI of the third circuit board 300. In other embodiments, the second segment 604 of the insulating shell 600 does not contact the inner surface 300SI of the third circuit board 300, that is, the second segment 604 and the inner surface 300SI of the third circuit board 300 are spaced apart from each other.

[0064] In an embodiment where the electronic component 100 is a capacitor, the first segment 602 of the insulating shell 600 directly contacts the side surface of the first electrode 102, the side surface of the second electrode 104, and the side surface of the dielectric layer 106. The first segment 602 of the insulating shell 600 may also directly contact the upper surface of the first electrode 102. Furthermore, the lower surface of the second electrode 104 directly contacts the third circuit board 300.

[0065] The insulating shell 600 has an internal cavity, and this cavity is a sealed space. The cavity is divided into several chambers by the inner wall 606. For example... Figure 6 As shown, the insulating shell 600 may have a first chamber 610 and a second chamber 612, and both chambers 610 and 612 are sealed spaces. The first chamber 610 is surrounded by a first segment 602, an inner wall 606, a third segment 608, and a fourth segment 609, while the second chamber 612 is surrounded by a second segment 604, an inner wall 606, a third segment 608, and a fourth segment 609. The first chamber 610 or the second chamber 612 may be a vacuum chamber. The first chamber 610 or the second chamber 612 may also be a non-vacuum chamber, for example, containing a gas (e.g., air).

[0066] The insulating shell 600 may be made of dielectric materials such as silicon oxide, silicon nitride, silicon oxynitride, phosphosilicate glass (PSG), borosilica glass (BSG), borophosphosilicate glass (BPSG), fluoride silicate glass (FSG), xerogel, aerogel, amorphous fluorinated carbon, parylene, benzocyclobutene, polyimide (PI), other suitable dielectric materials, or combinations thereof. Since the insulating shell 600 is located between the electronic component 100 and the circuit layer 204, to reduce the formation of parasitic capacitance, the insulating shell 600 may be made of a dielectric material with a low dielectric constant (i.e., dielectric constant < 3.9), such as porous silicon oxide, porous fluorides, silicon carbide, carbon-doped oxides, or similar materials.

[0067] The method of forming the insulating shell 600 may include injection molding, extrusion, blow molding, other suitable techniques, or a combination thereof.

[0068] In some embodiments, the insulating shell 600 is provided at the opening 500 (see reference). Figure 5 The operation in the first embodiment involves first setting the adhesive material 620 at the bottom of the opening 500, and then placing the insulating shell 600 into the opening 500. In other embodiments, setting the insulating shell 600 into the opening 500 involves first setting the adhesive material 620 on the insulating shell 600, and then placing the insulating shell 600 together with the adhesive material 620 into the opening 500.

[0069] An adhesive material 620 may be disposed between the insulating shell 600 and the third circuit board 300 to adhere the insulating shell 600 and the third circuit board 300, thereby fixing the insulating shell 600 within the third circuit board 300. In some embodiments, the adhesive material 620 directly contacts the insulating shell 600 and the third circuit board 300. Figure 6 In the illustrated embodiment, the adhesive material 620 directly contacts the fourth segment 609 and the third circuit board 300. The material of the adhesive material 620 may include epoxy resin, PI, polyurethane, or other suitable materials. In some embodiments, the adhesive material 620 may be a pressure-sensitive adhesive.

[0070] Please refer to Figure 7 , Figure 7 The diagram illustrates a cross-sectional view of the circuit board at one of the manufacturing stages, according to some embodiments of this application. Next, a hole 700 is formed in the insulating shell 600. Specifically, the hole 700 is formed in the third segment 608, such that the first chamber 610 is not a sealed space due to the hole 700. In other words, the first chamber 610 is connected to the outside.

[0071] Please refer to Figure 8 , Figure 8 The diagram illustrates a cross-sectional view of the circuit board at one of the manufacturing stages, according to some embodiments of this application. Next, heat exchange fluid 800 is added to the insulating shell 600. Specifically, heat exchange fluid 800 is added to the first chamber 610 through holes 700. Heat exchange fluid 800 can directly contact the first section 602 and the inner wall 606.

[0072] In subsequent processes, the heat exchange fluid 800 is sealed within and distributed within the first chamber 610. This location of the heat exchange fluid 800 around (e.g., on the side, or on the side and above) the electronic component 100 aids in heat dissipation.

[0073] In some embodiments, the heat exchange fluid 800 may flow within the first chamber 610. Furthermore, the heat exchange fluid 800 exists in both liquid and gaseous states within the first chamber 610. The amount of liquid added to the heat exchange fluid 800 can be determined based on process conditions or product requirements. In this embodiment, the liquid level of the heat exchange fluid 800 in the first chamber 610 is equal to or higher than the upper surface 100T of the electronic component 100. It is noteworthy that the liquid level of the heat exchange fluid 800 does not contact the third segment 608; in other words, the liquid state of the heat exchange fluid 800 does not completely fill the first chamber 610.

[0074] The material (in liquid state) of the heat exchange fluid 800 may include ammonia, acetone, methanol, ethanol, heptane, pure water, other suitable materials, or combinations thereof. Since the heat exchange fluid 800 can absorb and release heat energy through a phase change (discussed later), the material selection for the heat exchange fluid 800 should take into account the temperature range of the circuit board operation process to ensure that the heat exchange fluid 800 undergoes a phase change within the same temperature range. In some embodiments, the temperature of the circuit board operation process is between -70°C and 200°C, so a material that undergoes a phase change between -70°C and 200°C can be selected as the heat exchange fluid 800.

[0075] Please refer to Figure 9 , Figure 9 A cross-sectional view of the circuit board at one of the manufacturing stages is shown according to some embodiments of this application. Next, a heat dissipation layer 900 is disposed on the insulating shell 600. In some embodiments, the heat dissipation layer 900 directly contacts the insulating shell 600. The heat dissipation layer 900 may cover the hole 700. After the heat dissipation layer 900 covers the hole 700, the first chamber 610 returns to a sealed space. Therefore, the heat exchange fluid 800 can be sealed within the first chamber 610, surrounded by the first section 602, the inner wall 606, and the third section 608.

[0076] Furthermore, the heat dissipation layer 900 may also be disposed on the heat sink 304 and in direct contact with the heat sink 304. In some embodiments, the heat dissipation layer 900 extends continuously from the insulating shell 600 to the heat sink 304. In some embodiments, the heat dissipation layer 900 simultaneously directly contacts both the insulating shell 600 and the heat sink 304.

[0077] The material of the heat dissipation layer 900 may include epoxy resin, polyimide (PI), polyamide-imide (PAI), other suitable materials, or combinations thereof.

[0078] When the electronic component 100 is operating, the heat generated can be conducted to the liquid heat exchange fluid 800 through the insulating shell 600. The liquid heat exchange fluid 800 absorbs the heat and evaporates into a gaseous heat exchange fluid 800, and the gaseous heat exchange fluid 800 moves in the direction of the heat dissipation layer 900.

[0079] When the gaseous heat exchange fluid 800 reaches the third section 608 of the insulating shell 600, the gaseous heat exchange fluid 800 can condense into a liquid heat exchange fluid 800. Simultaneously, during the phase change of the heat exchange fluid 800, heat energy is released and transferred to the insulating shell 600. The heat energy is further conducted through the insulating shell 600 to the heat dissipation layer 900, and then discharged by the heat dissipation layer 900, thereby preventing heat energy accumulation in the electronic component 100 and the third circuit board 300. In some embodiments, while the heat dissipation layer 900 discharges heat energy, it can also transfer heat energy to the heat sink 304, and then discharge it from the heat sink 304, thereby further improving the efficiency of heat energy discharge and preventing heat energy accumulation in the electronic component 100 and the third circuit board 300.

[0080] After the gaseous heat exchange fluid 800 condenses into a liquid heat exchange fluid 800, the liquid heat exchange fluid 800 moves toward the first section 602 of the insulating shell 600 (i.e., the region adjacent to the electronic component 100). In this way, the heat exchange fluid 800 can circulate repeatedly within the insulating shell 600, and the heat generated by the electronic component 100 can be continuously conducted from the electronic component 100 to the heat dissipation layer 900 and the heat sink 304 for discharge in the manner described above.

[0081] Therefore, the first chamber 610 near the electronic component 100, the heat exchange fluid 800 inside the first chamber 610, and the heat dissipation layer 900 and heat sink 304 above it can help improve the efficiency of heat dissipation, thereby improving the performance of the electronic component 100.

[0082] On the other hand, a gas (e.g., air) exists in the second chamber 612 near the third circuit board 300. Since air has a low dielectric constant (approximately equal to 1), the second chamber 612 can act as an air gap, thereby reducing the parasitic capacitance between the electronic component 100 and the line layer 204 of the third circuit board 300, which helps the performance of the electronic component 100. In some embodiments, the second chamber 612 may be a vacuum chamber, which can provide an even lower dielectric constant.

[0083] In summary, this application provides a circuit board with embedded electronic components and a method for manufacturing the same. By setting an insulating shell around the electronic components, and having several chambers with different functions within the insulating shell, the heat dissipation efficiency of the circuit board with embedded capacitors is improved and parasitic capacitance is reduced, thereby improving the reliability and performance of the electronic components and the circuit board. Furthermore, when the electronic components are capacitors (e.g., planar capacitors), the capacitors are trimmed during the manufacturing process to achieve better precision, which also improves the reliability of the capacitors and the circuit board.

[0084] The foregoing has provided a brief overview of the features of several embodiments of this application, enabling those skilled in the art to more readily understand this application. It should be understood by anyone skilled in the art that this specification can easily serve as a basis for changes or designs to other structures or processes to achieve the same purpose and / or obtain the same advantages as the embodiments of this application. It will also be understood by anyone skilled in the art that equivalent structures as described above do not depart from the spirit and scope of this application, and that modifications, substitutions, and alterations can be made without departing from the spirit and scope of this application.

[0085] [Symbol Explanation] 100: Electronic components 100S: Side surface 100T: Upper surface 102: First electrode 104: Second electrode 106: Dielectric layer 200: First circuit board 202: Insulation layer 204: Line Layer 206: Metal foil layer 210: Groove 220: Second circuit board 222: Insulation layer 226: Metal foil layer 300: Third circuit board 302: Line Layer 304: Heat sink 300SI: Inner surface 400: Opening 500: Opening 600: Insulating shell 602: First paragraph 604: Second paragraph 606: Inner wall 608: Third paragraph 609: Fourth paragraph 610: First Chamber 612: Second Chamber 620: Adhesive material 700: Hole 800: Heat exchange fluid 900: Heat dissipation layer D: Distance X: Reference axis Y: Reference axis Z: Reference axis.

Claims

1. A method for manufacturing a circuit board, characterized in that, include: A groove is formed in the first circuit board; Electronic components are housed in the groove; A second circuit board is pressed onto the first circuit board so that the second circuit board and the first circuit board together form a third circuit board, wherein the electronic components are embedded in the third circuit board. An opening is formed in the third circuit board to expose the electronic components and the inner surface of the third circuit board in the opening; An insulating shell is disposed in the opening, wherein the insulating shell has: The first section surrounds and directly contacts the electronic component; The second segment is located next to the first segment and faces the inner surface of the third circuit board; The inner wall is located between the first segment and the second segment; The first chamber is surrounded by the first segment and the inner wall; as well as The second chamber is surrounded by the second segment and the inner wall; and Heat exchange fluid is added to the first chamber.

2. The method of manufacturing a circuit board according to claim 1, wherein forming the opening in the third circuit substrate includes extending the opening from the upper surface of the third circuit substrate into the third circuit substrate, and the bottom of the opening is lower than the bottom of the electronic component.

3. The method of manufacturing a circuit board according to claim 2, wherein the distance between the bottom of the opening and the bottom of the electronic component is greater than 10 micrometers.

4. The method for manufacturing a circuit board according to claim 1, wherein... Forming the opening in the third circuit board includes exposing the upper and side surfaces of the electronic component within the opening; and The insulating shell is configured in the opening to include the upper and side surfaces of the first segment in direct contact with the electronic component.

5. The method of manufacturing a circuit board according to claim 1, wherein the insulating shell in the opening includes an inner surface that allows the second segment to directly contact the third circuit substrate.

6. The method of manufacturing a circuit board according to claim 1, wherein setting the insulating shell in the opening includes setting an adhesive material between the insulating shell and the third circuit board, and attaching the insulating shell and the third circuit board together by means of the adhesive material.

7. The method of manufacturing a circuit board according to claim 1, further comprising disposing a heat dissipation layer on the insulating shell, wherein the heat dissipation layer is in direct contact with the insulating shell.

8. The method of manufacturing a circuit board according to claim 7, wherein a hole is formed in the insulating shell before the heat exchange fluid is added to the first chamber, wherein the heat exchange fluid is added to the first chamber through the hole.

9. The method of manufacturing a circuit board according to claim 8, wherein setting the heat dissipation layer on the insulating shell includes covering the hole with the heat dissipation layer to seal the heat exchange fluid in the first chamber.

10. The method of manufacturing a circuit board according to claim 1, wherein forming the opening in the third circuit substrate includes removing a portion of the electronic component so that the side surface of the electronic component is vertical.

11. The method of manufacturing a circuit board according to claim 1, further comprising: A heat sink is disposed on the third circuit board; as well as A heat dissipation layer is provided on the insulating shell and the heat dissipation component, and the heat dissipation component is in direct contact with the insulating shell and the heat dissipation component.

12. A circuit board, characterized in that, include: Circuit board; Electronic components are embedded in the circuit board; An insulating shell, embedded within the circuit board and located between the circuit board and the electronic component, the insulating shell comprising: The first section surrounds and directly contacts the electronic component; The second segment is located next to the first segment and faces the inner surface of the circuit board. The inner wall is located between the first segment and the second segment; A first chamber, surrounded by the first segment and the inner wall; and The second chamber is surrounded by the second segment and the inner wall; and The heat exchange fluid is distributed in the first chamber.

13. The circuit board of claim 12, wherein the insulating shell has an inverted U-shape in cross-section.

14. The circuit board of claim 12, wherein the heat exchange fluid comprises a liquid and a gas.

15. The circuit board of claim 14, wherein the level of the heat exchange fluid is equal to or higher than the upper surface of the electronic component.

16. The circuit board of claim 12, wherein air is present in the second cavity.

17. The circuit board of claim 12, further comprising: A heat dissipation layer is disposed on the insulating shell and in direct contact with the insulating shell.

18. The circuit board of claim 17, further comprising: A heat sink is disposed on the circuit board. The projection of the heat sink on the circuit board is offset from the projection of the electronic component on the circuit board; and The heat dissipation layer is disposed on the heat sink and in direct contact with the heat sink.

19. The circuit board of claim 12, wherein the electronic component is a capacitor and comprises: First electrode; The second electrode is disposed below the first electrode; as well as A dielectric layer is disposed between the first electrode and the second electrode, wherein the side surfaces of the first electrode, the second electrode, and the dielectric layer are coplanar with each other.

20. The circuit board according to claim 19, wherein The side surface of the first electrode, the side surface of the second electrode, and the side surface of the dielectric layer are in direct contact with the first segment; The upper surface of the first electrode directly contacts the first segment; and The lower surface of the second electrode is in direct contact with the circuit board.

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