TW202505943A - Circuit board and manufacturing method thereof - Google Patents

Abstract

A circuit board includes a core layer and two circuit structures. The core layer has a first surface and a second surface opposite to each other. The circuit structures are respectively disposed on the first surface and the second surface. Each circuit structure includes a substrate, an insulating layer, a metal pattern layer and a metal layer. The substrate includes two through holes arranged at intervals and exposing the first surface. The insulating layer is disposed in one of the through holes and contacts the first surface. The metal pattern layer includes a first heat conduction part and a circuit part. The first heat conduction part is disposed on the insulating layer. The circuit part is disposed in another one of the through holes and forms a cavity with the first surface. The metal layer includes a second heat conduction part and an electrical conduction part. The second heat conduction part is disposed on the first heat conduction part. The electrical conduction part is disposed on the substrate.

Description

Circuit board and manufacturing method thereof

The present invention relates to a circuit board and a manufacturing method thereof, and in particular to a circuit board with multiple functional element channels and a manufacturing method thereof.

As electronic products develop towards lightweight and miniaturization, more and more products are designing multiple channels of different signals or energies on the same circuit board, such as heat conduction channels for heat dissipation, high current channels, and high-speed or high-frequency signal transmission channels with cavities. However, component channels with different functions have different sizes (such as length or width) and structures, and making these channels with different functions on the same circuit board usually requires a very complex and difficult process, which makes it difficult to improve the yield, or even reduces it.

The purpose of the present invention is to provide a circuit board with multiple functional component channels, which can improve the product yield.

Another object of the present invention is to provide a method for manufacturing the above-mentioned circuit board to help improve the product yield of the above-mentioned circuit board.

A circuit board proposed in at least one embodiment of the present invention comprises a core layer, a first circuit structure and a second circuit structure. The core layer has a first surface and a second surface opposite to the first surface. The first circuit structure is arranged on the first surface and comprises a first substrate, a first insulating layer, a first metal pattern layer and a first metal layer. The first substrate comprises a first through-hole and a second through-hole arranged with an interval from the first through-hole, and the first through-hole and the second through-hole expose the first surface. The first insulating layer is arranged in the first through-hole and contacts the first surface. The first metal pattern layer comprises a first heat conducting portion and a first circuit portion, the first heat conducting portion is arranged on the first insulating layer, and the first circuit portion is arranged in the second through-hole and forms a first cavity with the first surface. The first metal layer includes a second heat-conducting portion and a first conductive portion, the second heat-conducting portion is arranged on the first heat-conducting portion, and the first conductive portion is arranged on the first substrate. The second circuit structure is arranged on the second surface and includes a second substrate, a second insulating layer, a second metal pattern layer and a second metal layer. The second substrate includes a third through-hole and a fourth through-hole arranged with intervals from the third through-hole, and the third through-hole and the fourth through-hole expose the second surface. The second insulating layer is arranged in the third through-hole and contacts the second surface. The second metal pattern layer includes a third heat-conducting portion and a second circuit portion, the third heat-conducting portion is arranged on the second insulating layer, the second circuit portion is arranged in the fourth through-hole and forms a second cavity with the second surface. The second metal layer includes a fourth heat-conducting portion and a second conductive portion, the fourth heat-conducting portion is arranged on the third heat-conducting portion, and the second conductive portion is arranged on the second substrate.

In at least one embodiment of the present invention, the circuit board includes a heat conduction channel, a circuit channel and a current channel, the heat conduction channel includes the first insulating layer, the first heat conduction part, the second heat conduction part, the second insulating layer, the third heat conduction part and the fourth heat conduction part, the circuit channel includes the first circuit part, the first cavity, the second circuit part and the second cavity, and the current channel includes the first conductive part and the second conductive part.

In at least one embodiment of the present invention, the first circuit structure further includes a third metal pattern layer, the third metal pattern layer includes a fifth heat conducting portion and a third conductive portion, the fifth heat conducting portion is disposed on the second heat conducting portion, and the third conductive portion is disposed on the first conductive portion, and the second circuit structure further includes a fourth metal pattern layer, the fourth metal pattern layer includes a sixth heat conducting portion and a fourth conductive portion, the sixth heat conducting portion is disposed on the fourth heat conducting portion, and the fourth conductive portion is disposed on the second conductive portion.

In at least one embodiment of the present invention, the heat conduction channel further includes the fifth heat conduction portion and the sixth heat conduction portion, and the current channel further includes the third conductive portion and the fourth conductive portion.

A method for manufacturing a circuit board proposed in at least one embodiment of the present invention includes providing a first initial substrate and a second initial substrate. Forming a first initial metal layer on the first initial substrate, and forming a second initial metal layer on the second initial substrate. Patterning the first initial substrate to form a first substrate having a first through hole and a second through hole arranged at intervals, and patterning the second initial substrate to form a second substrate having a third through hole and a fourth through hole arranged at intervals. Forming a first metal pattern layer in the first through hole and the second through hole, and forming a second metal pattern layer in the third through hole and the fourth through hole. Forming a first insulating layer on the first metal pattern layer in the first through hole, and forming a second insulating layer on the second metal pattern layer in the third through hole. Providing a core layer. Then, the first substrate and the core layer are pressed to form a first cavity in the second through hole, and the second substrate and the core layer are pressed to form a second cavity in the fourth through hole. The first initial metal layer is patterned to form a first metal layer, and the second initial metal layer is patterned to form a second metal layer.

In at least one embodiment of the present invention, the step of forming the first metal pattern layer includes forming a first heat conducting portion in the first through hole and forming a first circuit portion in the second through hole. The step of patterning the first initial metal layer includes forming a second heat conducting portion on the first heat conducting portion and forming a first conductive portion on the second substrate. The step of forming the second metal pattern layer includes forming a third heat conducting portion in the third through hole and forming a second circuit portion in the fourth through hole. The step of patterning the second initial metal layer includes forming a fourth heat conducting portion on the third heat conducting portion and forming a second conductive portion on the second substrate.

In at least one embodiment of the present invention, the first insulating layer, the first heat conducting portion, the second heat conducting portion, the second insulating layer, the third heat conducting portion and the fourth heat conducting portion form a heat conducting channel, the first circuit portion, the first cavity, the second circuit portion and the second cavity form a circuit channel, and the first conductive portion and the second conductive portion form a current channel.

In at least one embodiment of the present invention, before patterning the first initial metal layer and the second initial metal layer, the method further includes forming a third metal pattern layer on the first initial metal layer and forming a fourth metal pattern layer on the second initial metal layer.

In at least one embodiment of the present invention, the step of forming the third metal pattern layer includes forming a fifth heat conducting portion, the second heat conducting portion is located between the first heat conducting portion and the fifth heat conducting portion, and forming a third conductive portion, the first conductive portion is located between the first substrate and the third conductive portion, and the step of forming the fourth metal pattern layer includes forming a sixth heat conducting portion, the fourth heat conducting portion is located between the third heat conducting portion and the sixth heat conducting portion, and forming a fourth conductive portion, the second conductive portion is located between the second substrate and the fourth conductive portion.

In at least one embodiment of the present invention, the heat conduction channel further includes the fifth heat conduction portion and the sixth heat conduction portion, and the current channel further includes the third conductive portion and the fourth conductive portion.

In at least one embodiment of the present invention, the depth of the first through-hole and the depth of the second through-hole are respectively greater than the thickness of the first metal pattern layer, and the depth of the third through-hole and the depth of the fourth through-hole are respectively greater than the thickness of the second metal pattern layer.

In the following text, in order to clearly present the technical features of the present invention, the dimensions (e.g., length, width, thickness, and depth) of the elements (e.g., layers, films, substrates, and regions, etc.) in the drawings will be enlarged in unequal proportions, and the number of some elements will be reduced. Therefore, the description and explanation of the embodiments below are not limited to the number of elements in the drawings and the dimensions and shapes presented by the elements, but should cover the dimensions, shapes, and deviations therefrom caused by actual processes and/or tolerances. For example, the flat surface shown in the drawings may have rough and/or nonlinear features, and the sharp corners shown in the drawings may be rounded. Therefore, the elements presented in the drawings of the present invention are mainly used for illustration, and are not intended to accurately depict the actual shape of the elements, nor are they used to limit the scope of the patent application of the present invention.

Secondly, the words "approximately", "approximately" or "substantially" used in the present invention not only cover the numerical values and numerical ranges clearly recorded, but also cover the permissible deviation range that can be understood by a person of ordinary skill in the technical field to which the invention belongs, wherein the deviation range can be determined by the error generated during measurement, and the error is caused by the limitations of the measurement system or process conditions, for example. For example, two objects (such as the planes or traces of a substrate) are "substantially parallel" or "substantially perpendicular", wherein "substantially parallel" and "substantially perpendicular" respectively represent that the parallelism and perpendicularity between the two objects may include non-parallelism and non-perpendicularity caused by the permissible deviation range.

The spatially relative terms used in the present invention, such as "below", "under", "above", "on", etc., are for the purpose of facilitating the description of the relative relationship between one element or feature and another element or feature, as shown in the figure. The true meaning of these spatially relative terms includes other orientations. For example, when the figure is flipped 180 degrees up and down, the relationship between one element and another element may change from "below" or "under" to "above" or "on". In addition, the spatially relative descriptions used in the present invention should also be interpreted in the same way.

It should be understood that, although the present invention may use terms such as "first", "second", and "third" to describe various components or features, these components or features should not be limited by these terms. These terms are mainly used to distinguish one component from another component, or one feature from another feature. In addition, the term "or" used in the present invention may include any one or more combinations of the related listed items depending on the actual situation.

Although the present invention uses a series of operations or steps to illustrate the manufacturing method, the order in which these operations or steps are shown should not be interpreted as a limitation of the present invention. For example, certain operations or steps can be performed in different orders and/or simultaneously with other steps. In addition, each operation or step described herein can include a plurality of sub-steps or actions.

In addition, the present invention may be implemented or applied through other different specific embodiments, and the details of the present invention may also be combined, modified and changed in various embodiments based on different viewpoints and applications without departing from the concept of the present invention.

FIG1 is a partial cross-sectional schematic diagram of a circuit board of at least one embodiment of the present invention. Referring to FIG1 , the circuit board 1 includes a core layer 30, a first circuit structure 10, and a second circuit structure 20. The core layer 30 has a first surface S1 and a second surface S2, and the first surface S1 is opposite to the second surface S2. The first circuit structure 10 is disposed on the first surface S1 of the core layer 30, and the second circuit structure 20 is disposed on the second surface S2.

The first circuit structure 10 includes a first substrate 110, a first insulating layer 112, a first metal pattern layer 114 and a first metal layer 116. The first substrate 110 includes a first through hole T1 and a second through hole T2, which are arranged at intervals and expose the first surface S1 of the core layer 30.

The first insulating layer 112 is disposed in the first through hole T1 and contacts the first surface S1 of the core layer 30. The first metal pattern layer 114 includes a first heat conducting portion 114h and a first circuit portion 114t. The first heat conducting portion 114h is disposed in the first through hole T1 and disposed on the first insulating layer 112. The first circuit portion 114t is disposed in the second through hole T2 and forms a first cavity C1 with the first surface S1, that is, the first circuit portion 114t does not contact the first surface S1. The first metal layer 116 includes a second heat conducting portion 116h and a first conductive portion 116c. The second heat conducting portion 116h is disposed on the first heat conducting portion 114h. The first conductive portion 116c is disposed on the first substrate 110.

The second circuit structure 20 includes a second substrate 210, a second insulating layer 212, a second metal pattern layer 214 and a second metal layer 216. The second substrate 210 includes a third through hole T3 and a fourth through hole T4, which are arranged at intervals and expose the second surface S2 of the core layer 30.

The second insulating layer 212 is disposed in the third through hole T3 and contacts the second surface S2 of the core layer 30. The second metal pattern layer 214 includes a third heat conducting portion 214h and a second circuit portion 214t. The third heat conducting portion 214h is disposed in the third through hole T3 and disposed on the second insulating layer 212. The second circuit portion 214t is disposed in the fourth through hole T4 and forms a second cavity C2 with the second surface S2, that is, the second circuit portion 214t does not contact the second surface S2. The second metal layer 216 includes a fourth heat conducting portion 216h and a second conductive portion 216c. The fourth heat conducting portion 216h is disposed on the third heat conducting portion 214h. The second conductive portion 216c is disposed on the second substrate 210.

By means of the above structural design, the insulating layer and the heat conducting part, the circuit part and the cavity, and the conducting part can be used as component channels with different functions respectively, thereby forming a circuit board with component channels with multiple functions.

As shown in FIG1 , the circuit board 1 includes a heat conduction channel HC, a circuit channel TC, and a current channel CC. The heat conduction channel HC includes a first insulating layer 112, a first heat conduction portion 114h of a first metal pattern layer 114, a second heat conduction portion 116h of a first metal layer 116, a second insulating layer 212, a third heat conduction portion 214h of a second metal pattern layer 214, and a fourth heat conduction portion 216h of a second metal layer 216. The circuit channel TC includes a first circuit portion 114t of a first metal pattern layer 114, a first cavity C1, a second circuit portion 214t of a second metal pattern layer 214, and a second cavity C2. The current channel CC includes a first conductive portion 116c of a first metal layer 116, and a second conductive portion 216c of a second metal layer 216.

In some embodiments, the first circuit portion 114t of the first metal pattern layer 114 is combined with the first cavity C1 and the second circuit portion 214t of the second metal pattern layer 214 is combined with the second cavity C2, so that the circuit channel TC is used as a high-speed or high-frequency signal transmission circuit channel, such as used in 4G or 5G communication components.

In some embodiments, a heat conduction channel HC having a heat dissipation effect is formed by providing the second heat conduction portion 116h of the first metal layer 116 and the fourth heat conduction portion 216h of the second metal layer 216. In addition, a current channel CC suitable for transmitting high current is formed by providing the first conductive portion 116c of the first metal layer 116 and the second conductive portion 216c of the second metal layer 216.

In some embodiments, the number of the first through hole T1, the second through hole T2, the third through hole T3 and the fourth through hole T4 may be more than one. As shown in FIG1 , the number of the first through hole T1 and the third through hole T3 is one, and the number of the second through hole T2 and the fourth through hole T4 is two, but the present invention is not limited thereto, and the number of through holes may be adjusted according to different design requirements.

In some embodiments, the first heat conducting portion 114 h of the first metal pattern layer 114 contacts the first insulating layer 112 , the second heat conducting portion 116 h of the first metal layer 116 contacts the first heat conducting portion 114 h , and the first conducting portion 116 c of the first metal layer 116 contacts the first substrate 110 .

In some embodiments, the third heat conducting portion 214h of the second metal pattern layer 214 contacts the second insulating layer 212, the fourth heat conducting portion 216h of the second metal layer 216 contacts the third heat conducting portion 214h, and the second conductive portion 216c of the second metal layer 216 contacts the second substrate 210.

Continuing to refer to FIG. 1 , the first circuit structure 10 further includes a third metal pattern layer 118, the third metal pattern layer 118 includes a fifth heat conducting portion 118h and a third conductive portion 118c, the fifth heat conducting portion 118h is disposed on the second heat conducting portion 116h, and the third conductive portion 118c is disposed on the first conductive portion 116c. The second circuit structure 20 further includes a fourth metal pattern layer 218, the fourth metal pattern layer 218 includes a sixth heat conducting portion 218h and a fourth conductive portion 218c, the sixth heat conducting portion 218h is disposed on the fourth heat conducting portion 216h, and the fourth conductive portion 218c is disposed on the second conductive portion 216c.

As shown in FIG. 1 , the heat conducting channel HC further includes a fifth heat conducting portion 118h of the third metal pattern layer 118 and a sixth heat conducting portion 218h of the fourth metal pattern layer 218 , and the current channel CC further includes a third conductive portion 118c of the third metal pattern layer 118 and a fourth conductive portion 218c of the fourth metal pattern layer 218 .

In some embodiments, the thickness of the third metal pattern layer 118 is greater than the thickness of the first metal pattern layer 114, and the thickness of the fourth metal pattern layer 218 is greater than the thickness of the second metal pattern layer 214. The fifth heat conducting portion 118h of the third metal pattern layer 118 and the sixth heat conducting portion 218h of the fourth metal pattern layer 218 with greater thickness can further enhance the heat dissipation effect of the heat conducting channel HC. In addition, the third conductive portion 118c of the third metal pattern layer 118 and the fourth conductive portion 218c of the fourth metal pattern layer 218 with greater thickness can further enhance the high current resistance effect of the current channel CC.

In some embodiments, the fifth heat conducting portion 118h of the third metal pattern layer 118 contacts the second heat conducting portion 116h, and the third conductive portion 118c of the third metal pattern layer 118 contacts the first conductive portion 116c. In some embodiments, the sixth heat conducting portion 218h of the fourth metal pattern layer 218 contacts the fourth heat conducting portion 216h, and the fourth conductive portion 218c of the fourth metal pattern layer 218 contacts the second conductive portion 216c.

2A to 2L are partial cross-sectional views of a circuit board of at least one embodiment of the present invention at different process stages. Referring to FIG. 2A , a first initial substrate 110′ and a second initial substrate 210′ are provided, and a first initial metal layer 116′ is formed on the first initial substrate 110′ and a second initial metal layer 216′ is formed on the second initial substrate 210′. In some embodiments, the material of the first initial substrate 110′ and the second initial substrate 210′ may include a resin, and the material of the first initial metal layer 116′ and the second initial metal layer 216′ may include a metal, such as copper.

2B , the first initial substrate 110′ is patterned to form the first substrate 110 having the first through-holes T1 and the second through-holes T2 arranged at intervals, and the second initial substrate 210′ is patterned to form the second substrate 210 having the third through-holes T3 and the fourth through-holes T4 arranged at intervals. In some embodiments, the first through-holes T1, the second through-holes T2, the third through-holes T3, and the fourth through-holes T4 may be formed by an etching process, such as dry etching.

Referring to FIG. 2C , a first metal pattern layer 114 is formed in the first through hole T1 and the second through hole T2, and a second metal pattern layer 214 is formed in the third through hole T3 and the fourth through hole T4. In some embodiments, the material of the first metal pattern layer 114 and the second metal pattern layer 214 may include a metal, such as copper. In some embodiments, the first metal pattern layer 114 and the second metal pattern layer 214 may be formed by an electroplating process. In some embodiments, the depth of the first through hole T1 and the depth of the second through hole T2 are respectively greater than the thickness of the first metal pattern layer 114, and the depth of the third through hole T3 and the depth of the fourth through hole T4 are respectively greater than the thickness of the second metal pattern layer 214.

As shown in FIG. 2C , the step of forming the first metal pattern layer 114 includes forming the first heat conducting portion 114h in the first through hole T1 and the first circuit portion 114t in the second through hole T2. The step of forming the second metal pattern layer 214 includes forming the third heat conducting portion 214h in the third through hole T3 and the second circuit portion 214t in the fourth through hole T4. In some embodiments, the depth of the first through hole T1 is greater than the thickness of the first heat conducting portion 114h, the depth of the second through hole T2 is greater than the thickness of the first circuit portion 114t, the depth of the third through hole T3 is greater than the thickness of the third heat conducting portion 214h, and the depth of the fourth through hole T4 is greater than the thickness of the second circuit portion 214t.

Referring to FIG. 2D , a first insulating layer 112 is formed on the first metal pattern layer 114 in the first through hole T1, and a second insulating layer 212 is formed on the second metal pattern layer 214 in the third through hole T3, so as to obtain a first initial circuit structure 10 ′. In some embodiments, the materials of the first insulating layer 112 and the second insulating layer 212 may include resin. In some embodiments, the depth of the first through hole T1 is approximately equal to the sum of the thicknesses of the first heat conducting portion 114h and the first insulating layer 112, and the depth of the third through hole T3 is approximately equal to the sum of the thicknesses of the third heat conducting portion 214h and the second insulating layer 212.

Referring to FIG. 2E and FIG. 2F , a core layer 30 is provided, and the first initial circuit structure 10 ′, the second initial circuit structure 20 ′ and the core layer 30 are pressed together, that is, the first substrate 110 and the core layer 30 are pressed together to form a first cavity C1 located in the second through hole T2, and the second substrate 210 and the core layer 30 are pressed together to form a second cavity C2 located in the fourth through hole T4. However, the manufacturing method of the second initial circuit structure 20 ′ is the same as that of the first initial circuit structure 10 ′, as shown in FIG. 2A to FIG. 2D , so the same contents will not be repeated here.

As shown in FIG. 2E and FIG. 2F , the core layer 30 has a first surface S1 and a second surface S2 opposite to the first surface S1. The core layer 30 is disposed between the first substrate 110 and the second substrate 210, and the first substrate 110, the second substrate 210 and the core layer 30 are pressed together so that the first substrate 110 is attached to the first surface S1 of the core layer 30, and the second substrate 210 is attached to the second surface S2 of the core layer 30.

Specifically, the first substrate 110, the second substrate 210, and the core layer 30 are pressed together to form a first cavity C1 between the first circuit portion 114t formed in the second through hole T2 and the first surface S1 of the core layer 30, and a second cavity C2 between the second circuit portion 214t formed in the fourth through hole T4 and the second surface S2 of the core layer 30. In addition, the first insulating layer 112 formed in the first through hole T1 contacts the first surface S1 of the core layer 30, and the second insulating layer 212 formed in the third through hole T3 contacts the second surface S2 of the core layer 30. In some embodiments, the material of the core layer 30 may include a resin, such as a low flow prepreg or a no flow prepreg.

Referring to FIG. 2G to FIG. 2L , the first initial metal layer 116′ is patterned to form the first metal layer 116, and the second initial metal layer 216′ is patterned to form the second metal layer 216. First, as shown in FIG. 2G , a first photoresist film F1 is formed on the first initial metal layer 116′, and a second photoresist film F2 is formed on the second initial metal layer 216′. In some embodiments, the first photoresist film F1 and the second photoresist film F2 can be formed on the first initial metal layer 116′ and the second initial metal layer 216′, respectively, by a lamination process.

As shown in FIG2H , the first photoresist film F1 is patterned to form a first opening O1 and a second opening O2 exposing the first initial metal layer 116′, and the second photoresist film F2 is patterned to form a third opening O3 and a fourth opening O4 exposing the second initial metal layer 216′. In some embodiments, the first opening O1 is formed corresponding to the position of the first heat conducting portion 114h, that is, corresponding to the first through hole T1, and the third opening O3 is formed corresponding to the position of the third heat conducting portion 214h, that is, corresponding to the third through hole T3. In some embodiments, the first opening O1, the second opening O2, the third opening O3, and the fourth opening O4 can be formed by a lithography process.

As shown in FIG2I , a third metal pattern layer 118 is formed on the first initial metal layer 116′, and a fourth metal pattern layer 218 is formed on the second initial metal layer 216′. Specifically, forming the third metal pattern layer 118 includes forming a fifth heat conducting portion 118h on the first initial metal layer 116′ in the first opening O1, and forming a third conductive portion 118c on the first initial metal layer 116′ in the second opening O2, and forming the fourth metal pattern layer 218 includes forming a sixth heat conducting portion 218h on the second initial metal layer 216′ in the third opening O3, and forming a fourth conductive portion 218c on the second initial metal layer 216′ in the fourth opening O4. In some embodiments, the material of the third metal pattern layer 118 and the fourth metal pattern layer 218 may include metal, such as copper. In some embodiments, the third metal pattern layer 118 and the fourth metal pattern layer 218 may be formed by an electroplating process.

As shown in FIG. 2J , a first protective layer E1, a second protective layer E2, a third protective layer E3, and a fourth protective layer E4 are formed on the fifth heat conducting portion 118h, the third conductive portion 118c, the sixth heat conducting portion 218h, and the fourth conductive portion 218c, respectively. In some embodiments, the materials of the first protective layer E1, the second protective layer E2, the third protective layer E3, and the fourth protective layer E4 may include metal, such as tin. In some embodiments, the first protective layer E1, the second protective layer E2, the third protective layer E3, and the fourth protective layer E4 may be formed by an electroplating process. In some embodiments, the first protective layer E1, the second protective layer E2, the third protective layer E3, and the fourth protective layer E4 directly contact the fifth heat conducting portion 118h, the third conductive portion 118c, the sixth heat conducting portion 218h, and the fourth conductive portion 218c, respectively.

As shown in FIG2K , the first photoresist film F1 and the second photoresist film F2 are removed. Next, as shown in FIG2L , the first initial metal layer 116′ below the third metal pattern layer 118 is patterned using the first protective layer E1 and the second protective layer E2 as masks to form the first metal layer 116, and the second initial metal layer 216′ below the fourth metal pattern layer 218 is patterned using the third protective layer E3 and the fourth protective layer E4 as masks to form the second metal layer 216. In some embodiments, the first initial metal layer 116′ and the second initial metal layer 216′ may be patterned by an etching process.

In detail, the step of patterning the first initial metal layer 116' includes forming the second heat conducting portion 116h on the first heat conducting portion 114h and forming the first conductive portion 116c on the first substrate 110, and the step of patterning the second initial metal layer 216' includes forming the fourth heat conducting portion 216h on the third heat conducting portion 214h and forming the second conductive portion 216c on the second substrate 210. In other words, the second heat conducting portion 116h is formed between the first heat conducting portion 114h and the fifth heat conducting portion 118h, the first conductive portion 116c is formed between the first substrate 110 and the third conductive portion 118c, the fourth heat conducting portion 216h is formed between the third heat conducting portion 214h and the sixth heat conducting portion 218h, and the second conductive portion 216c is formed between the second substrate 210 and the fourth conductive portion 218c.

Please refer to Figures 1 and 2L. After patterning the first initial metal layer 116' and the second initial metal layer 216', the first protective layer E1, the second protective layer E2, the third protective layer E3 and the fourth protective layer E4 are removed to form the first circuit structure 10 and the second circuit structure 20, and a circuit board 1 including a heat conduction channel HC, a circuit channel TC and a current channel CC as shown in Figure 1 can be obtained.

In summary, in at least one embodiment of the circuit board and its manufacturing method, the insulating layer and the heat conducting part, the wiring part and the cavity, and the conducting part can be used as component channels with different functions, thereby forming a circuit board with multiple functional component channels and improving product yield and reliability.

Although the present invention has been disclosed as above by way of embodiments, they are not intended to limit the present invention. A person having ordinary knowledge in the relevant technical field may make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the attached patent application.

1: Circuit board 10: First circuit structure 10': First initial circuit structure 110: First substrate 110': First initial substrate 112: First insulating layer 114: First metal pattern layer 114h: First heat conducting portion 114t: First circuit portion 116: First metal layer 116': First initial metal layer 116c: First conductive portion 116h: Second heat conducting portion 118: Third metal pattern layer 118c: Third conductive portion 118h: Fifth heat conducting portion 20: Second circuit structure 20': Second initial circuit structure 210: Second substrate 210': Second initial substrate 212: Second insulating layer 214: Second metal pattern layer 214h: Third heat conducting portion 214t: second circuit portion 216: second metal layer 216': second initial metal layer 216c: second conductive portion 216h: fourth heat conducting portion 218: fourth metal pattern layer 218c: fourth conductive portion 218h: sixth heat conducting portion 30: core layer C1: first cavity C2: second cavity CC: current channel E1: first protective layer E2: second protective layer E3: third protective layer E4: fourth protective layer F1: first photoresist film F2: second photoresist film HC: heat conducting channel O1: first opening O2: second opening O3: third opening O4: fourth opening S1: first surface S2: second surface T1: first through hole T2: second through hole T3: third through hole T4: fourth through hole TC: circuit channel

FIG. 1 is a partial cross-sectional schematic diagram of a circuit board according to at least one embodiment of the present invention; and FIG. 2A to FIG. 2L are partial cross-sectional diagrams of a circuit board according to at least one embodiment of the present invention at different manufacturing stages.

Domestic storage information (please note the order of storage institution, date, and number) None Overseas storage information (please note the order of storage country, institution, date, and number) None

1: Circuit board

10: First circuit structure

110: First substrate

112: First insulation layer

114: First metal pattern layer

114h: First heat transfer part

114t: First Line Department

116: First metal layer

116c: first conductive part

116h: Second heat transfer part

118: The third metal pattern layer

118c: Third conductive part

118h: Fifth heat conduction part

20: Second circuit structure

210: Second substrate

212: Second insulation layer

214: Second metal pattern layer

214h: The third heat transfer part

214t: Second line unit

216: Second metal layer

216c: Second conductive part

216h: Fourth heat transfer part

218: Fourth metal pattern layer

218c: Fourth conductive part

218h: Sixth heat transfer unit

30: Core layer

C1: First cavity

C2: Second cavity

CC: Current Channel

HC: Heat conduction channel

S1: First surface

S2: Second surface

T1: First piercing

T2: Second piercing

T3: Third piercing

T4: Fourth piercing

TC: Line channel

Claims (11)

A circuit board comprises: A core layer having a first surface and a second surface opposite to the first surface; A first circuit structure disposed on the first surface, the first circuit structure comprising: A first substrate comprising a first through-hole and a second through-hole disposed at intervals from the first through-hole, wherein the first through-hole and the second through-hole expose the first surface; A first insulating layer disposed in the first through-hole and contacting the first surface; A first metal pattern layer comprising a first heat-conducting portion and a first circuit portion, wherein the first heat-conducting portion is disposed on the first insulating layer, the first circuit portion is disposed in the second through-hole and forms a first cavity with the first surface; and A first metal layer, including a second heat-conducting part and a first conductive part, wherein the second heat-conducting part is arranged on the first heat-conducting part, and the first conductive part is arranged on the first substrate; and A second circuit structure, arranged on the second surface, the second circuit structure comprising: A second substrate, including a third through-hole and a fourth through-hole arranged with intervals from the third through-hole, wherein the third through-hole and the fourth through-hole expose the second surface; A second insulating layer, arranged in the third through-hole and contacting the second surface; A second metal pattern layer, including a third heat-conducting part and a second circuit part, wherein the third heat-conducting part is arranged on the second insulating layer, and the second circuit part is arranged in the fourth through-hole and forms a second cavity with the second surface; and A second metal layer includes a fourth heat conducting portion and a second conductive portion, wherein the fourth heat conducting portion is disposed on the third heat conducting portion, and the second conductive portion is disposed on the second substrate. The circuit board as described in claim 1 includes a heat-conducting channel, a circuit channel and a current channel, wherein the heat-conducting channel includes the first insulating layer, the first heat-conducting part, the second heat-conducting part, the second insulating layer, the third heat-conducting part and the fourth heat-conducting part, the circuit channel includes the first circuit part, the first cavity, the second circuit part and the second cavity, and the current channel includes the first conductive part and the second conductive part. A circuit board as described in claim 2, wherein the first circuit structure further includes a third metal pattern layer, the third metal pattern layer includes a fifth heat-conducting portion and a third conductive portion, the fifth heat-conducting portion is arranged on the second heat-conducting portion, and the third conductive portion is arranged on the first conductive portion, wherein the second circuit structure further includes a fourth metal pattern layer, the fourth metal pattern layer includes a sixth heat-conducting portion and a fourth conductive portion, wherein the sixth heat-conducting portion is arranged on the fourth heat-conducting portion, and the fourth conductive portion is arranged on the second conductive portion. A circuit board as described in claim 3, wherein the heat conductive channel further includes the fifth heat conductive portion and the sixth heat conductive portion, and the current channel further includes the third conductive portion and the fourth conductive portion. A method for manufacturing a circuit board, comprising: Providing a first initial substrate and a second initial substrate; Forming a first initial metal layer on the first initial substrate; Forming a second initial metal layer on the second initial substrate; Patterning the first initial substrate to form a first substrate having a first through hole and a second through hole arranged at intervals; Patterning the second initial substrate to form a second substrate having a third through hole and a fourth through hole arranged at intervals; Forming a first metal pattern layer in the first through hole and in the second through hole; Forming a second metal pattern layer in the third through hole and in the fourth through hole; Forming a first insulating layer on the first metal pattern layer in the first through hole; Forming a second insulating layer on the second metal pattern layer in the third through hole; Providing a core layer; Pressing the first substrate and the core layer to form a first cavity in the second through-hole; Pressing the second substrate and the core layer to form a second cavity in the fourth through-hole; Patterning the first initial metal layer to form a first metal layer; and Patterning the second initial metal layer to form a second metal layer. A method for manufacturing a circuit board as described in claim 5, wherein the step of forming the first metal pattern layer includes forming a first heat-conducting portion in the first through-hole and forming a first circuit portion in the second through-hole, and the step of patterning the first initial metal layer includes forming a second heat-conducting portion on the first heat-conducting portion and forming a first conductive portion on the first substrate, wherein the step of forming the second metal pattern layer includes forming a third heat-conducting portion in the third through-hole and forming a second circuit portion in the fourth through-hole, and the step of patterning the second initial metal layer includes forming a fourth heat-conducting portion on the third heat-conducting portion and forming a second conductive portion on the second substrate. A method for manufacturing a circuit board as described in claim 6, wherein the first insulating layer, the first heat-conducting portion, the second heat-conducting portion, the second insulating layer, the third heat-conducting portion and the fourth heat-conducting portion form a heat-conducting channel, the first circuit portion, the first cavity, the second circuit portion and the second cavity form a circuit channel, and the first conductive portion and the second conductive portion form a current channel. The method for manufacturing a circuit board as described in claim 7, wherein before patterning the first initial metal layer and the second initial metal layer, it further includes: forming a third metal pattern layer on the first initial metal layer; and forming a fourth metal pattern layer on the second initial metal layer. A method for manufacturing a circuit board as described in claim 8, wherein the step of forming the third metal pattern layer includes forming a fifth thermally conductive portion, the second thermally conductive portion is located between the first thermally conductive portion and the fifth thermally conductive portion, and forming a third conductive portion, wherein the first conductive portion is located between the first substrate and the third conductive portion, wherein the step of forming the fourth metal pattern layer includes forming a sixth thermally conductive portion, the fourth thermally conductive portion is located between the third thermally conductive portion and the sixth thermally conductive portion, and forming a fourth conductive portion, wherein the second conductive portion is located between the second substrate and the fourth conductive portion. A method for manufacturing a circuit board as described in claim 9, wherein the heat conductive channel further includes the fifth heat conductive portion and the sixth heat conductive portion, and the current channel further includes the third conductive portion and the fourth conductive portion. A method for manufacturing a circuit board as described in claim 5, wherein the depth of the first through-hole and the depth of the second through-hole are respectively greater than the thickness of the first metal pattern layer, and wherein the depth of the third through-hole and the depth of the fourth through-hole are respectively greater than the thickness of the second metal pattern layer.

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