Circuit substrate, circuit board, and method for manufacturing circuit board

Abstract

A circuit board is divided into a main region and multiple bending regions adjacent to the main region. The circuit board includes a bendable circuit layer and a dielectric layer. The bendable circuit layer extends from the main region to the multiple bending regions. The dielectric layer is disposed on the bendable circuit layer. The dielectric layer includes a first dielectric portion and multiple second dielectric portions, the first dielectric portion being located in the main region, and the multiple second dielectric portions being located in the multiple bending regions respectively. Each of the multiple second dielectric portions has a first sidewall facing the first dielectric portion, a second sidewall opposite to the first sidewall, and a width between the first and second sidewalls, wherein the widths of the multiple second dielectric portions are equal to each other. This circuit board allows for electrical connection between an upper circuit board and a lower circuit board using only a single reflow soldering process, which can improve production capacity and reduce manufacturing costs. The gap between the upper and lower circuit board connections facilitates heat dissipation for electronic components.

Description

Technical Field

[0001] This invention relates to a circuit board, a circuit board, and a method for manufacturing the circuit board. Background Technology

[0002] Currently, there are stacked structures made by stacking multiple circuit boards. In such stacked structures, a support frame is set between the lower circuit board containing electronic components and the upper circuit board so that a space can be formed between the lower and upper circuit boards to accommodate the electronic components. This support frame is usually made of metal and is soldered to the aforementioned upper and lower circuit boards so that the upper and lower circuit boards can be electrically connected to each other.

[0003] However, the aforementioned support frame completely surrounds the electronic components on the lower circuit board, sealing them in a closed space. This makes it difficult for the heat generated by the electronic components to dissipate to the external environment, thus affecting the performance of the components. Secondly, the support frame is typically soldered between the upper and lower circuit boards, requiring at least two soldering processes to place it between the two layers, which is detrimental to throughput. Therefore, there is an urgent need to develop a circuit board and its manufacturing method to overcome these shortcomings. Summary of the Invention

[0004] The circuit board provided by this invention has multiple outwardly protruding bending regions, which are used for bending and serve as a support structure between the circuit board and another circuit board. The support structure in the circuit board of this invention is formed by bending the bending regions of the lower circuit board upwards, and the support structure has a circuit structure. Therefore, the upper circuit board can be electrically connected to the lower circuit board through the support structure, thereby improving the integration density of the circuit board. Furthermore, this invention allows for electrical connection between the upper and lower circuit boards using only a single reflow soldering process, increasing production capacity and reducing manufacturing costs. Simultaneously, the gap between the upper and lower circuit boards facilitates heat dissipation for electronic components.

[0005] The circuit board provided in at least one embodiment of the present invention is divided into a main region and a plurality of bending regions, wherein the plurality of bending regions are adjacent to the main region. The circuit board includes a bendable circuit layer and a dielectric layer. The bendable circuit layer extends from the main region to the plurality of bending regions. The dielectric layer is disposed on the bendable circuit layer, wherein the dielectric layer includes a first dielectric portion and a plurality of second dielectric portions, the first dielectric portion being located in the main region, and the plurality of second dielectric portions being respectively located in the plurality of bending regions. Each of the plurality of second dielectric portions has a first sidewall facing the first dielectric portion, a second sidewall opposite to the first sidewall, and a width located between the first sidewall and the second sidewall, wherein the plurality of widths of the plurality of second dielectric portions are equal to each other. The first dielectric portion, the plurality of second dielectric portions, and the bendable circuit layer define a plurality of grooves, and each of the plurality of grooves is located between the first sidewalls of adjacent first dielectric portions and second dielectric portions.

[0006] In at least one embodiment of the present invention, the first dielectric portion has a first stepped sidewall, and the first sidewall has a second stepped sidewall, with the first stepped sidewall facing the second stepped sidewall.

[0007] In at least one embodiment of the invention, the width of each of the plurality of grooves gradually widens along the direction from the bendable circuit layer toward the dielectric layer.

[0008] The circuit board provided in at least one embodiment of the present invention includes a first circuit board, a plurality of support structures, and a second circuit board. The first circuit board includes a dielectric layer and a flexible circuit layer, with the dielectric layer disposed above the flexible circuit layer. The plurality of support structures are disposed above the first circuit board. The flexible circuit layer includes a first circuit portion located in the first circuit board and a plurality of second circuit portions located in the plurality of support structures, wherein the first circuit portion connects to the plurality of second circuit portions, and each of the plurality of second circuit portions extends from the first circuit portion to a support structure, wherein the first circuit portion and the second circuit portions are not coplanar. The second circuit board covers the plurality of support structures and the first circuit board, and is electrically connected to the first circuit board through the plurality of support structures.

[0009] In at least one embodiment of the present invention, the dielectric layer includes a first dielectric portion having a first stepped sidewall and a second dielectric portion having a second stepped sidewall, wherein when the bendable circuit layer is folded, the first stepped sidewall connects to the second stepped sidewall.

[0010] In at least one embodiment of the present invention, the circuit board further includes a bonding material, wherein the bonding material is disposed between a plurality of support structures and a second circuit substrate.

[0011] In at least one embodiment of the present invention, the top of each of the plurality of support structures includes a conductive line layer electrically connected to a second circuit board.

[0012] In at least one embodiment of the present invention, the inner wall of each of the plurality of support structures has a conductive circuit layer, the conductive circuit layer being electrically connected to a bendable circuit layer.

[0013] In at least one embodiment of the present invention, there are multiple gaps between the first circuit board, the second circuit board and the multiple support structures, wherein each gap is located between two adjacent support structures and communicates with the accommodating space between the first circuit board and the second circuit board.

[0014] The method for manufacturing a circuit board according to at least one embodiment of the present invention includes the following steps: providing a first circuit substrate, wherein the first circuit substrate is divided into a main body region and a plurality of bending regions, the plurality of bending regions being adjacent to the main body region, the first circuit substrate including a dielectric layer and a bendable circuit layer, the dielectric layer being disposed above the bendable circuit layer, the bendable circuit layer extending from the main body region to the plurality of bending regions; folding the plurality of bending regions to the main body region, wherein a first circuit portion of the bendable circuit layer is located on the outermost layer of the first circuit substrate, and a second circuit portion of each of the bendable circuit layers is located on the outer wall surface of a plurality of support structures, such that the first circuit portion and the second circuit portion are not coplanar; disposing a second circuit substrate on the first circuit substrate, wherein the second circuit substrate covers the plurality of support structures and the first circuit substrate, and is electrically connected to the first circuit substrate through the plurality of support structures.

[0015] In at least one embodiment of the present invention, the method of manufacturing a circuit board further includes: mounting electronic components on the upper surface of a first circuit substrate before bending a plurality of bending regions to a main body region.

[0016] In at least one embodiment of the present invention, the method of manufacturing a circuit board further includes: after bending multiple bending regions to a main body region, fixing multiple support structures to the upper surface of a first circuit substrate using adhesive material. Attached Figure Description

[0017] The various aspects of this application can be best understood by reading in conjunction with the accompanying drawings and the following detailed description. It should be understood that, in accordance with industry standard practice, the various features are not drawn to scale. In fact, for clarity, the dimensions of the various features can be arbitrarily increased or decreased.

[0018] Figures 1 to 6 This is a perspective view of a circuit board at various stages of the manufacturing process according to an embodiment of the present invention.

[0019] Figure 7A According to an embodiment of the present invention Figure 1 A partial cross-sectional schematic diagram of line A-A'.

[0020] Figure 7BAccording to an embodiment of the present invention Figure 3 A partial cross-sectional schematic diagram of line B-B'.

[0021] Figure 8A According to another embodiment of the present invention Figure 1 A partial cross-sectional schematic diagram of line A-A'.

[0022] Figure 8B According to another embodiment of the present invention Figure 3 A partial cross-sectional schematic diagram of line B-B'. Detailed Implementation

[0023] In the following text, to clearly present the technical features of this application, the dimensions (e.g., length, width, thickness, and depth) of the elements (e.g., circuit boards, dielectric layers, and flexible circuit layers) in the accompanying drawings will be enlarged proportionally, and the number of some elements may be reduced. Therefore, the description and explanation of the embodiments below are not limited to the number of elements in the drawings or the size and shape of the elements, but should cover the dimensions, shapes, and deviations from both caused by actual manufacturing processes and / or tolerances. For example, a flat surface shown in the drawings may have rough and / or non-linear characteristics, and an acute angle shown in the drawings may be rounded. Therefore, the elements presented in the accompanying drawings are primarily for illustration and are not intended to precisely depict the actual shape of the elements, nor are they intended to limit the scope of the claims in this application.

[0024] In addition, spatial relative terms such as "below," "below," "lower than," "above," "above," and other similar terms are used here for the convenience of describing the relationship between one element or feature and another element or feature in the figure. Spatial relative terms cover not only the orientation depicted in the figure but also other orientations of the device during use or operation. That is, when the orientation of the device differs from that in the figure (rotated 90 degrees or in other orientations), the spatial relative terms used in this disclosure can also be interpreted accordingly.

[0025] It will be understood that although terms such as “first,” “second,” etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, without departing from the scope of the embodiments, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. As used herein, the term “and / or” includes any and all combinations of one or more of the associated listed items.

[0026] Figures 1 to 6 For a circuit board 100 according to an embodiment of the present invention (please refer to...) Figure 6 (This is a three-dimensional schematic diagram of each stage of the process. Please refer to it.) Figure 1The circuit board 110 is divided into a main region MR and multiple bent regions BR, with the multiple bent regions BR adjacent to the main region MR. Specifically, the multiple bent regions BR are located around the main region MR. It is understood that the multiple bent regions BR protrude outwards from the side boundaries of the main region MR, and the length of the multiple bent regions BR is less than the length of the boundary of the main region MR. For example, in this embodiment, each bent region BR is strip-shaped, and the main region MR may protrude from both ends of each bent region BR, such as... Figure 1 As shown. The circuit board 110 extends along the XY plane and has a thickness extending along the Z direction.

[0027] It should be noted that, Figures 1 to 6 The accompanying drawings are only for illustrating the relative positions of the main body region MR, the bending region BR, and the various components. A detailed description of the layered structures within the main body region MR and the bending region BR, as well as the grooves formed between the main body region MR and the bending region BR, will be provided later. Figure 7A , Figure 7B , Figure 8A and Figure 8B Presented.

[0028] Figure 7A According to an embodiment of the present invention Figure 1 A partial cross-sectional view of line A-A' is shown. The circuit board 110 includes dielectric layers 112, 114, and 116 and a bendable circuit layer 118. Dielectric layers 112, 114, and 116 are disposed above the bendable circuit layer 118. Specifically, dielectric layers 112, 114, and 116 include first dielectric portions 112a, 114a, and 116a and second dielectric portions 112b, 114b, and 116b. The first dielectric portions 112a, 114a, and 116a are located in the main region MR, while the second dielectric portions 112b, 114b, and 116b are located in the bending region BR.

[0029] like Figure 7A As shown, the bendable circuit layer 118 includes a first circuit portion 118a and a second circuit portion 118b, the first circuit portion 118a being connected to the second circuit portion 118b, and the bendable circuit layer 118 extending from the body region MR to the bending region BR. In some embodiments, the bendable circuit layer 118 may be formed, for example, of one or at least two layers of copper foil. In other embodiments, the bendable circuit layer 118 may be, for example, the circuit layer of a flexible circuit board (FCB). Therefore, Figure 7A A flexible substrate can be disposed below the flexible circuit layer 118, wherein the flexible substrate can be made of a polymer material, such as polyimide (PI).

[0030] like Figure 7A As shown, the second dielectric portions 112b, 114b, and 116b have first sidewalls 112bs1, 114bs1, and 116bs1 and second sidewalls 112bs2, 114bs2, and 116bs2. The first sidewalls 112bs1, 114bs1, and 116bs1 face the first sidewalls 112as1, 114as1, and 116as1 of the first dielectric portions 112a, 114a, and 116a.

[0031] Please also refer to Figure 1 and Figure 7A The second dielectric portion 112b has a width W between its first sidewall 112bs1 and second sidewall 112bs2, wherein the widths of the plurality of second dielectric portions are equal to each other. In other words, please refer to... Figure 1 The width W in the four bent regions BR is equal to that of each other.

[0032] Please refer to this again. Figure 7A The first dielectric portions 112a, 114a and 116a, the second dielectric portions 112b, 114b and 116b, and the flexible circuit layer 118 define a groove R (not in the...). Figure 1 (As shown in the diagram). The groove R is located between the first sidewalls 112as1, 114as1, and 116as1 of the first dielectric portions 112a, 114a, and 116a and the first sidewalls 112bs1, 114bs1, and 116bs1 of the second dielectric portions 112b, 114b, and 116b. The width of the groove R gradually increases along the direction from the bendable wiring layer 118 toward the dielectric layers 112, 114, and 116, as shown in the diagram. Figure 7A As shown. In other words, the width (i.e., distance) between the first sidewall 112as1 and the first sidewall 112bs1 is less than the width (i.e., distance) between the first sidewall 114as1 and the first sidewall 114bs1, and the width (i.e., distance) between the first sidewall 114as1 and the first sidewall 114bs1 is less than the width (i.e., distance) between the first sidewall 116as1 and the first sidewall 116bs1.

[0033] like Figure 7A As shown, the first sidewalls 112as1, 114as1, and 116as1 of the first dielectric portions 112a, 114a, and 116a have first stepped sidewalls. The first sidewalls 112bs1, 114bs1, and 116bs1 of the second dielectric portions 112b, 114b, and 116b have second stepped sidewalls. The first stepped sidewalls face the second stepped sidewalls. In other words, the first stepped sidewalls are formed by the first sidewalls 112as1, 114as1, and 116as1, and the second stepped sidewalls are formed by the first sidewalls 112bs1, 114bs1, and 116bs1.

[0034] In other embodiments, the circuit board 110 may contain only one dielectric layer. For example, Figure 7A The circuit board 110 may consist only of the dielectric layer 112, while Figure 7A Dielectric layers 114 and 116 can be omitted. Therefore, the circuit board 110 may include only one dielectric layer, and is not limited to multiple layers. Furthermore, in embodiments where the number of dielectric layers is only one, this dielectric layer may also have stepped sidewalls, so the first and second stepped sidewalls are not limited to being composed of sidewalls of multiple dielectric layers. In embodiments where the number of dielectric layers is only one, this dielectric layer may not have stepped sidewalls, i.e., the first sidewall 112as1 of the first dielectric portion 112a and the first sidewall 112bs1 of the second dielectric portion 112b are both vertical sidewalls.

[0035] Please refer to Figure 2 Electronic components 120 are mounted on the upper surface ts of the circuit board 110. Electronic components 120 may be, for example, capacitors, resistors, inductors, central processing units (CPUs), and / or graphics processing units (GPUs), but are not limited thereto. It is understood that the size, number, and arrangement of electronic components 120 are not limited to these. Figure 2 Other dimensions, quantities, and arrangements of the electronic components 120, as illustrated, are also included in embodiments of the present invention.

[0036] Please refer to Figure 3 Fold multiple bending areas BR (please refer to) Figure 2 ) to the main region MR. Figure 7B According to an embodiment of the present invention Figure 3 A partial cross-sectional schematic diagram of line B-B'.

[0037] For more details, please also refer to... Figure 3 , Figure 7A and Figure 7B After the rotation and bending region BR is about 90 degrees to the main region MR, the original second dielectric portions 112b, 114b and 116b and the second line portion 118b form the support structure SS located in the main region MR.

[0038] Please refer to Figure 7BThe first circuit portion 118a of the bendable circuit layer 118 is located on the outermost layer of the circuit substrate 110, and the second circuit portion 118b of the bendable circuit layer 118 is located on the outer wall surface of the support structure SS, so that the first circuit portion 118a and the second circuit portion 118b are not coplanar. That is, the first circuit portion 118a is a structure extending along the XY plane, while the second circuit portion 118b is a structure extending along the YZ plane. It is understood that the support structure SS described herein includes the second dielectric portions 112b, 114b, and 116b and the second circuit portion 118b.

[0039] Still referencing Figure 7B Because the first sidewalls 112as1, 114as1, and 116as1 of the first dielectric portions 112a, 114a, and 116a have first stepped sidewalls, and the first sidewalls 112bs1, 114bs1, and 116bs1 of the second dielectric portions 112b, 114b, and 116b have second stepped sidewalls, after the bending region BR is folded approximately 90 degrees, the first stepped sidewall engages with the second stepped sidewall. In other words, the first stepped sidewall and the second stepped sidewall cooperate with each other, and the first dielectric portions 112a, 114a, and 116a and the supporting structure SS form a structure with close contact.

[0040] Understandably, the height of the support structure SS depends on the width W of the second dielectric portion 112b (see reference). Figure 7A The width W of the second dielectric portion 112b (i.e., the height of the support structure SS) can be adjusted according to the actual needs of the circuit board.

[0041] Please refer to Figure 4 In multiple bending areas BR (please refer to) Figure 2 After the main body region MR is reached, multiple support structures SS are fixed to the upper surface ts of the circuit board 110 using dispensing material 130. The dispensing material 130 can be, for example, a resin material. The dispensing material 130 can prevent the second dielectric portions 112b, 114b, and 116b (see reference) from being blocked. Figure 7B The stacked structures deform, while also preventing the second dielectric portions 112b, 114b, and 116b from flipping back to their original state. Figure 7B The planar form.

[0042] Please refer to Figure 5 A bonding material 140 is disposed on a plurality of support structures SS. The bonding material 140 may be, for example, solder paste, but is not limited thereto.

[0043] Please refer to Figure 6A circuit board 150 is disposed on a circuit board 110, wherein the circuit board 150 covers a plurality of support structures SS and is electrically connected to the circuit board 110 through the plurality of support structures SS. In other words, the bonding material 140 (see reference) Figure 5 It is disposed between multiple support structures SS and circuit board 150. It is understood that the circuit board 150 and circuit board 110 are electrically connected together by reflow bonding material 140.

[0044] It is worth noting that, please refer to Figure 6 The circuit board 150, the multiple support structures SS, and the circuit board 110 have multiple gaps G, each gap G being located between two adjacent support structures SS. Each gap G connects to an accommodating space (not shown) between the circuit boards 150 and 110, which is also the space where the electronic component 120 is located, so that outside air can enter the space where the electronic component 120 is located through the gap G, thereby facilitating the heat dissipation of the electronic component 120 on the circuit board 110.

[0045] Please refer to this again. Figure 6 and Figure 7B The top of the support structure SS includes a conductive layer 160 (e.g., Figure 7B As shown in the diagram, the conductive layer 160 is electrically connected to the circuit board 150 (e.g., Figure 6 (As illustrated). It is understood that the conductive layer 160 is formed beforehand, prior to bending the second dielectric portions 112b, 114b, and 116b and the second line portion 118b. Furthermore, the conductive layer 160 can be formed using laser cutting of conductive blind vias.

[0046] Figure 8A According to another embodiment of the present invention Figure 1 A partial cross-sectional schematic diagram of line A-A'. Figure 8B According to another embodiment of the present invention Figure 3 A partial cross-sectional schematic diagram of line B-B'. Figure 8A and Figure 7A The difference lies in the distribution of the conduction layer 160, and Figure 8B and Figure 7B The difference also lies in the distribution of the conduction layer 160.

[0047] Please refer to Figure 8A and Figure 8B The inner wall iw of the supporting structure SS has a conductive layer 160, which is electrically connected to a bendable circuit layer 118. The conductive layer 160 can be formed by laser cutting conductive blind vias.

[0048] In summary, the circuit board provided by this invention has multiple outwardly protruding bending regions, which are used for bending and serve as a support structure between the circuit board and another circuit board. The support structure in the circuit board of this invention is formed by bending the bending regions of the lower circuit board upwards, and the support structure has a circuit structure. Therefore, the upper circuit board can be electrically connected to the lower circuit board through the support structure, thereby improving the integration density of the circuit board. Furthermore, this invention allows for electrical connection between the upper and lower circuit boards using only a single reflow soldering process, increasing production capacity and reducing the manufacturing cost of additional support frames. Secondly, a gap exists between the upper and lower circuit boards in this invention, connecting the accommodating space between them, which facilitates heat dissipation for electronic components.

[0049] The foregoing overview of the features of various embodiments enables those skilled in the art to better understand the nature of this application. Those skilled in the art should understand that this application can be readily used as the basis for designing or modifying other processes and structures to achieve the same objectives and / or benefits as the embodiments described herein. Those skilled in the art should also recognize that such equivalent constructions do not depart from the spirit and scope of this application, and that various changes, substitutions, and modifications can be made without departing from the spirit and scope of this application.

[0050] [Symbol Explanation]

[0051] 100: Circuit board

[0052] 110: Circuit board

[0053] 112, 114, 116: Dielectric layers

[0054] 112a, 114a, 116a: First dielectric section

[0055] 112as1, 114as1, 116as1: First sidewall

[0056] 112bs1, 114bs1, 116bs1: First sidewall

[0057] 112bs2, 114bs2, 116bs2: Second sidewall

[0058] 112b, 114b, 116b: Second dielectric section

[0059] 118: Flexible circuit layer

[0060] 118a: First Line Section

[0061] 118b: Second Line Section

[0062] 120: Electronic components

[0063] 130: Dispensing material

[0064] 140: Bonding material

[0065] 150: Circuit board

[0066] 160: Conductor Layer

[0067] ts: upper surface

[0068] iw: Inner wall

[0069] MR: Main Region

[0070] BR: Bending area

[0071] SS: Supporting structure

[0072] R: Groove

[0073] W: Width

[0074] A-A': line

[0075] B-B': line

[0076] X, Y, Z: Direction.

Claims

1. A circuit board, characterized by, comprising: a first circuit substrate, wherein the first circuit substrate is divided into a main area and a plurality of bending areas, the plurality of bending areas being adjacent to the main area, the first circuit substrate comprising a dielectric layer and a bendable circuit layer, and the dielectric layer being disposed above the bendable circuit layer; a plurality of support structures disposed above the first circuit substrate, wherein the plurality of support structures are formed on the main area by rotating the plurality of bending areas, the bendable circuit layer comprising a first circuit portion in the first circuit substrate and a plurality of second circuit portions in the plurality of support structures, wherein the first circuit portion connects the plurality of second circuit portions, and each of the plurality of second circuit portions extends from the first circuit portion to the support structure, wherein the first circuit portion and the second circuit portion are not coplanar; and a second circuit substrate covering the plurality of support structures and the first circuit substrate and electrically connected to the plurality of support structures and the first circuit substrate.

2. The circuit board of claim 1, wherein the dielectric layer comprises a first dielectric portion having a first stepped sidewall and a second dielectric portion having a second stepped sidewall, wherein the first stepped sidewall meets the second stepped sidewall.

3. The circuit board of claim 1, wherein, further comprising a bonding material, wherein the bonding material is disposed between the plurality of support structures and the second circuit substrate.

4. The circuit board of claim 1, wherein a top portion of each of the plurality of support structures comprises a conductive circuit layer electrically connected to the second circuit substrate.

5. The circuit board of claim 1, wherein an inner wall of each of the plurality of support structures has a conductive circuit layer electrically connected to the bendable circuit layer.

6. The circuit board of claim 1, wherein there are a plurality of gaps between the first circuit substrate, the second circuit substrate, and the plurality of support structures, wherein each of the gaps is between two adjacent support structures and is in communication with a receiving space between the first circuit substrate and the second circuit substrate.

7. A method of manufacturing a circuit board, characterized by, comprising: providing a first circuit substrate, wherein the first circuit substrate is divided into a main area and a plurality of bending areas, the plurality of bending areas being adjacent to the main area, the first circuit substrate comprising a dielectric layer and a bendable circuit layer, the dielectric layer being disposed above the bendable circuit layer, the bendable circuit layer extending from the main area to the plurality of bending areas; folding the plurality of bending areas to the main area to form a plurality of support structures on the main area, wherein a first circuit portion of the bendable circuit layer is on an outermost layer of the first circuit substrate, and a second circuit portion of each of the bendable circuit layer is on an outer wall surface of the plurality of support structures, such that the first circuit portion and the second circuit portion are not coplanar; A second circuit substrate is disposed on the first circuit substrate, wherein the second circuit substrate covers the plurality of support structures and the first circuit substrate and is electrically connected to the first circuit substrate through the plurality of support structures.

8. The method of manufacturing a circuit board according to claim 7, wherein Further comprising: Before bending the plurality of bending regions to the main body region, an electronic component is mounted on the upper surface of the first circuit substrate.

9. The method of manufacturing a circuit board according to claim 7, wherein, Further comprising: After bending the plurality of bending regions to the main body region, the plurality of support structures are fixed on the upper surface of the first circuit substrate by using a dispensing material.

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