Circuit board and method for manufacturing the same

Abstract

Some embodiments of the present disclosure provide a circuit board and a method for manufacturing the circuit board, comprising the following steps: providing a first conductive layer; providing an adhesive material and at least one conductive block, wherein the adhesive material has conductivity; using the adhesive material to adhere the at least one conductive block to a surface of the first conductive layer; providing an insulating layer; disposing the insulating layer on the surface of the first conductive layer and on the at least one conductive block; and disposing a second conductive layer on the insulating layer. The circuit board provided by the present disclosure provides greater flexibility in the design of the thickness of the internal conductive block and the circuit pattern.

Description

Technical Field

[0001] The present disclosure relates to a circuit board and a manufacturing method thereof. Specifically, the present disclosure relates to a circuit board with embedded conductive blocks and a manufacturing method thereof. Background Art

[0002] The current method for manufacturing circuit boards with embedded conductive blocks (local thickening) is mainly through two methods. One is to electroplate the conductive layer, and the second is to first form a through hole in the insulating layer of the substrate, fill the conductive material in the through hole, and then form a conductive layer on the upper surface and lower surface of the insulating layer and the conductive material filled in the through hole.

[0003] However, the thickness of the electroplating in the first method is limited, for example, it is impossible to form a conductive block structure with a thickness greater than 200 microns. The second method is limited by the thickness of the conventional substrate, resulting in a limited thickness of the conductive block. Therefore, in the current method of embedding the conductive block, the extent of the conductive block thickness increase is limited.

[0004] On the other hand, in the second method, if the conductive layer needs to be further patterned to form a circuit, the patterned area needs to avoid the portion filled with the conductive material, which limits the design flexibility of the circuit pattern.

[0005] Therefore, how to make the conductive blocks embedded in the circuit board have the flexibility of adjusting the thickness and improve the flexibility of the patterned area of ​​the conductive layer are problems that need to be solved urgently. Summary of the invention

[0006] One aspect of the present disclosure is a circuit board, comprising: a first conductive layer, at least one adhesive layer, at least one conductive block, an insulating layer, and a second conductive layer. At least one adhesive layer is disposed on the surface of the first conductive layer, and at least one adhesive layer has conductivity. At least one conductive block comprises a top surface and a bottom surface relative to the top surface, wherein the bottom surface contacts at least one adhesive layer and is bonded to the first conductive layer via at least one adhesive layer. An insulating layer covers the surface of the first conductive layer and at least one conductive block. The second conductive layer is disposed on the insulating layer.

[0007] In some embodiments, the thickness of the first conductive layer is relative to the first conductive layer, at least one

[0008] The ratio of the thickness of the adhesive layer to the thickness of the at least one conductive block is greater than 1:15.

[0009] In some embodiments, the total thickness of the first conductive layer, the at least one adhesive layer, and the at least one conductive block is 20 micrometers to 3 millimeters.

[0010] In some embodiments, the thickness of the first conductive layer is greater than 3 microns.

[0011] In some embodiments, at least one adhesive layer has a thickness of less than 5 microns.

[0012] In some embodiments, the at least one adhesive layer contacts a surface area of ​​the bottom surface of the at least one conductive block, but does not exceed a surface area of ​​the bottom surface of the at least one conductive block.

[0013] In some embodiments, a plurality of conductive blocks are further included, wherein the plurality of conductive blocks have different sizes, different shapes, or different sizes and shapes.

[0014] In some embodiments, the device further includes at least one conductive column, which penetrates the second conductive layer and the insulating layer and extends to the top surface of the at least one conductive block.

[0015] In some embodiments, a top portion of the at least one conductive pillar is coplanar with the second conductive layer.

[0016] In some embodiments, at least one conductive pillar is a conductive pillar, and the at least one conductive block is a conductive block, and the conductive pillar is located on the conductive block.

[0017] In some embodiments, at least one conductive pillar is a plurality of conductive pillars, and at least one conductive block is a conductive block, and the plurality of conductive pillars are located on the conductive block.

[0018] In some embodiments, the first conductive layer is a patterned first conductive layer, the second conductive layer is a patterned second conductive layer, or a combination thereof.

[0019] In some embodiments, the material of at least one adhesion layer comprises metal particles.

[0020] One aspect of the present disclosure is a method for manufacturing a circuit board, comprising: providing a first conductive layer; providing an adhesive material and at least one conductive block, wherein the adhesive material has conductivity; using the adhesive material to bond at least one conductive block to the surface of the first conductive layer; providing an insulating layer; disposing the insulating layer on the surface of the first conductive layer and on at least one conductive block; and disposing a second conductive layer on the insulating layer.

[0021] In some embodiments, the step of bonding at least one conductive block to the surface of the first conductive layer using an adhesive material includes heating the adhesive material to make the adhesive material fluid, and then bonding at least one conductive block to the surface of the first conductive layer using the adhesive material.

[0022] In some embodiments, an insulating layer is disposed on the surface of the first conductive layer and at least one

[0023] The steps on the conductive block include: removing a portion of the insulating layer to form at least one groove that is recessed upward, covering and accommodating at least one conductive block in the at least one groove; and pressing the insulating layer, at least one conductive block and the first conductive layer together.

[0024] In some embodiments, the method further includes forming at least one conductive column, wherein the at least one conductive column penetrates the second conductive layer and the insulating layer and extends to a top surface of the at least one conductive block.

[0025] In some embodiments, the step of forming at least one conductive pillar includes: removing a portion of the insulating layer and a portion of the second conductive layer to expose the top surface of at least one conductive block to form at least one blind hole; and filling the at least one blind hole with a conductive material so that the conductive material contacts the second conductive layer to form at least one conductive pillar.

[0026] In some embodiments, after the step of disposing the second conductive layer on the insulating layer, the step further includes patterning the first conductive layer and the second conductive layer.

[0027] It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the disclosure as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present disclosure can be more fully understood by reading the following detailed description of embodiments with reference to the accompanying drawings.

[0029] Figures 1A to 1G The process of manufacturing a circuit board according to some embodiments of the present disclosure is exemplarily described.

[0030] FIG. 2A to FIG. 2B The process of manufacturing a circuit board including conductive pillars according to some embodiments of the present disclosure is exemplarily described.

[0031] FIG. 3A to FIG. 3B The process of manufacturing a circuit board including conductive pillars according to other embodiments of the present disclosure is exemplarily described.

[0032] Figure 4 The process of manufacturing a circuit board including circuits according to some embodiments of the present disclosure is exemplarily described.

[0033] Figure 5 The process of manufacturing a circuit board including circuits and conductive pillars according to some embodiments of the present disclosure is exemplarily described.

[0034]

Main component symbol description

[0035] 100: Circuit board 110: Conductive layer

[0036] 111: first conductive layer 1111: surface

[0037] 112: second conductive layer 113: patterned first conductive layer

[0038] 114: patterned second conductive layer 120: adhesive layer

[0039] 130: conductive block 131: first conductive block

[0040] 132: second conductive block 133: third conductive block

[0041] 134: top surface 135: top surface

[0042] 140: insulating layer 150: conductive column

[0043] A: Groove B: Blind hole DETAILED DESCRIPTION

[0044] It is understood that the different implementations or examples provided below may implement different features of the subject matter of the present disclosure. The examples of specific components and arrangements are intended to simplify the present disclosure rather than to limit the present disclosure. Of course, these are merely examples and are not intended to be limiting. For example, the description below of a first feature being formed on a second feature includes the two being in direct contact, or the two being separated by other additional features rather than in direct contact. In addition, the present disclosure may repeat reference numbers and / or symbols in multiple embodiments. Such repetition is for simplicity and clarity and does not represent a relationship between the various embodiments and / or configurations discussed.

[0045] The terms used in this specification generally have common meanings in the art and in the context in which they are used. The embodiments used in this specification, including examples of any term discussed herein, are merely illustrative and do not limit the scope and meaning of the disclosure or any exemplary term. Likewise, the disclosure is not limited to some of the embodiments provided in this specification.

[0046] It will be understood that although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another element. For example, without departing from the scope of the present embodiment, the first element may be referred to as the second element, and similarly, the second element may be referred to as the first element.

[0047] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0048] As used herein, the terms “include,” “including,” “have,” etc. should be understood as open ended, that is, meaning including but not limited to.

[0049] Figures 1A to 1G The process of manufacturing a circuit board according to some embodiments of the present disclosure is exemplarily described.

[0050] First, please see Figure 1A A first conductive layer 111 is provided. In some embodiments, the first conductive layer 111 is a metal, such as copper (copper foil), but not limited thereto. In some embodiments, the first conductive layer has a thickness greater than 3 microns, such as 3 microns to 10 microns (3 microns, 4 microns, 5 microns, 6 microns, 7 microns, 8 microns, 9 microns, or 10 microns), but not limited thereto.

[0051] Next, please see Figure 1B as well as Figure 1C An adhesive material having conductivity is applied to the surface 1111 of the first conductive layer 111 as the adhesive layer 120, and the conductive block 130 is bonded to the surface 1111 of the first conductive layer 111. In some embodiments, an adhesive material may be applied to the bottom surface of the conductive block 130 first, and the conductive block 130 is bonded to the surface 1111 of the first conductive layer 111.

[0052] In some embodiments, the surface area of ​​the adhesive layer 120 contacting the bottom surface of the conductive block 130 does not exceed the surface area of ​​the bottom surface of the conductive block 130, that is, the adhesive layer 120 does not extend beyond the bottom surface of the conductive block 130. In some embodiments, the adhesive material includes a conductive paste having a conductive substance, such as a transient liquid phase sintering (TLPS) adhesive material. The transient liquid phase sintering adhesive material includes a combination of metal particles (such as copper and tin) and a solvent. The principle is that by heating the combination of metal particles that can generate a liquid phase at the adhesive interface, after forming an interface liquid phase flow state, as the reaction and diffusion proceed, the melting point of the liquid phase gradually rises, thereby making the melting point of the adhesive layer 120 exceed the adhesive temperature, solidifying into the adhesive layer 120, and achieving the effect of adhering to the first conductive layer 111. The adhesive layer 120 formed by the transient liquid phase sintering adhesive material not only has high reliability, but also has low resistance (excellent conductivity, the resistivity can be less than 1x10 -6Ω·m) and high thermal conductivity (thermal conductivity greater than 20W / mk) effects, can conduct the conductive block 130 and the first conductive layer 111, and assist the heat dissipation of the conductive block 130. In one embodiment, the transient liquid phase sintering adhesive material is heated to a temperature higher than 150°C and lower than the melting point of the first conductive layer 111 and the conductive block 130 (for example, 160°C, 170°C, 180°C, 190°C, or 200°C, but not limited thereto), so that the transient liquid phase sintering adhesive material is in a liquid phase flow state. In one embodiment, the adhesive layer 120 has a thickness of less than 5 microns, for example, 0.01 microns to 5 microns, for example, 1 micron, 2 microns, 3 microns, 4 microns, or any range of the foregoing HTP200513CN Page 6 / 8

[0053] Values, but not limited to these.

[0054] In some embodiments, the size and shape of the conductive blocks 130 are not limited. In one embodiment, the size or shape of the conductive blocks 130 may be the same; in another embodiment, the size or shape of the conductive blocks 130 may be different (e.g. Figure 1C In one embodiment, the conductive block 130 may be a long strip-shaped extended structure, such as a conductive pad or a circuit.

[0055] In some embodiments, the total thickness of the first conductive layer 111, the adhesive layer 120, and the conductive block 130 may be 20 microns to 3 millimeters, such as 20 microns, 40 microns, 60 microns, 80 microns, 100 microns, 200 microns, 400 microns, 600 microns, 800 microns, 1 millimeter, 2 millimeters, 3 millimeters, or any value in the aforementioned range, but not limited thereto. It is worth noting that, by using the adhesive layer 120 and first adhering the conductive block 130 to the first conductive layer 111 and then joining other components, the conductive block 130 is not limited by the thickness of a conventional circuit board, providing a more flexible application for the structure of the circuit board with the embedded conductive block 130. For example, in some embodiments, a thicker conductive block 130 can be used so that the ratio of the thickness of the first conductive layer 111 to the thickness of the first conductive layer 111, the adhesion layer 120 and the conductive block 130 is less than 1:15, for example 1:15 to 1:30 (for example 1:16, 1:17, 1:18, 1:19, 1:20, 1:21, 1:22, 1:23, 1:24, 1:25, 1:26, 1:27, 1:28, 1:29, 1:30, or a ratio in any of the foregoing ranges), but is not limited thereto.

[0056] Next, please see Figure 1D to Figure 1G . Figure 1D , providing an insulating layer 140. Figure 1E, a portion of the insulating layer 140 is removed, and a recess A which is recessed upward and can accommodate the conductive block 130 is formed on the surface of the insulating layer 140 . Figure 1F as well as Figure 1G , an insulating layer 140 is disposed on the surface 1111 of the first conductive layer 111 and on the conductive block 130, so that the conductive block 130 is accommodated in the groove A; at the same time, a second conductive layer 112 is provided, and the second conductive layer 112 is disposed on the insulating layer 140 to obtain the circuit board 100.

[0057] In some embodiments, the material and thickness of the second conductive layer 112 may be the same as or similar to those of the first conductive layer 111 .

[0058] In other embodiments, the step of disposing the insulating layer 140 on the surface 1111 of the first conductive layer 111 and on the conductive block 130 may also include first forming a groove A on the first insulating layer that can accommodate the conductive block 130, and then covering the conductive block 130 and the first conductive layer 111 with the first insulating layer including the groove A, so that the groove A accommodates the conductive block 130. Then, according to the required thickness of the insulating layer 140, one or more second insulating layers that have not been processed for groove formation are disposed on the first insulating layer including the groove A. Finally, the second conductive layer 112 is disposed on the second insulating layer or the uppermost second insulating layer to obtain the circuit board 100. In some embodiments, the steps of disposing an insulating layer 140 on the surface 1111 of the first conductive layer 111 and on the conductive block 130 and disposing the second conductive layer 112 on the insulating layer 140 include using a thermal pressing method to simultaneously press the first conductive layer 111, the insulating layer 140, the conductive block 130 and the second conductive layer 112 to obtain the circuit board 100, wherein the first conductive layer 111, the conductive block 130, the adhesive layer 120 and the second conductive layer 112 are all conductive and electrically connected to each other to form a conductive structure.

[0059] Please see FIG. 2A to FIG. 2B , exemplarily describing a process of manufacturing a circuit board including conductive pillars 150 according to some embodiments of the present disclosure.

[0060] First, please see Figure 2A , remove a portion of the insulating layer 140 and a portion of the second conductive layer 112 to expose the top surface 134 of the conductive block 130, and form a blind hole B. Next, please see you. Figure 2B , fill the blind hole B with a conductive material to form a conductive column 150. That is, the conductive column 150 is disposed through the second conductive layer 112 and the insulating layer 140, and extends to the top surface 134 of the conductive block 130. In some embodiments, the conductive column 150 may not be disposed on the top surface 135 of a portion of the conductive block 130 (for example, the third conductive block 133).

[0061] In some embodiments, the conductive material may be the same as the material of the conductive layer 110, such as copper. In some embodiments, the blind hole B may be formed by laser or selective etching, and then the second conductive layer 112 is used as an electroplating seed layer to fill the blind hole B with the conductive material to form the conductive pillar 150. In some embodiments, the top of the conductive pillar 150 is coplanar with the second conductive layer 112.

[0062] The conductive pillars 150 are used to assist the conductive block 130 in heat dissipation. Those skilled in the art may selectively form one or more conductive pillars 150 on the conductive block 130 based on heat dissipation requirements, cost, and subsequent manufacturing processes.

[0063] In some embodiments, see FIG. 3A to FIG. 3B , exemplarily describing the process of manufacturing a circuit board 100 including a conductive column 150 according to other embodiments of the present disclosure, wherein in addition to one conductive column 150 formed on one conductive block 130, it also includes a state where multiple conductive columns 150 are formed on one conductive block 130. At present, the conductive block 130 that is prone to heat during use can be enlarged. HTP200513CN Page 8 / 8

[0064] Heat dissipation area. Figure 3A As an example, one blind hole B is formed on the first conductive block 131 , and two blind holes B are formed on the second conductive block 132 . Figure 3B Then, the blind hole B is filled with a conductive material to form a conductive column 150. In some embodiments, Figure 3A as well as Figure 3B Can be similar to Figure 2A as well as Figure 2B The method described above forms the blind hole B and the conductive column 150 .

[0065] That is, the circuit board 100 in the present disclosure may include a conductive column 150 on the conductive block 130 , a plurality of conductive columns 150 on the conductive block 130 , no conductive column 150 on the conductive block 130 , or a combination of the above configurations.

[0066] In some embodiments, see Figure 4 The first conductive layer 111, the second conductive layer 112, or both can be patterned through lithography and etching to form a patterned first conductive layer 113, a patterned second conductive layer 114, or a patterned first conductive layer 113 and a patterned second conductive layer 114 for use as circuits.

[0067] For example, the first conductive layer 111 and the second conductive layer 112 may be further patterned in the circuit board 100 including the conductive blocks 130 to form a patterned first conductive layer 113 and a patterned second conductive layer 114. Figure 5 , the first conductive layer 111 and the second conductive layer 112 can be further patterned in the circuit board 100 including the conductive blocks 130 and the conductive pillars 150. It is worth emphasizing that in some embodiments of the present disclosure, the conductive blocks 130 do not penetrate the insulating layer 140 and the second conductive layer 112, and some conductive blocks 130 do not have the conductive pillars 150 (such as the third conductive blocks 133). Therefore, when patterning the second conductive layer 112, it is not limited by the position of the conductive blocks 130.

[0068] The circuit boards and methods for manufacturing circuit boards disclosed in some embodiments of the present disclosure utilize conductive adhesive materials to bond conductive layers and conductive blocks. Compared to the conventional method of forming conductive blocks on conductive layers by electroplating or filling conductive materials into through holes in insulating layers in substrates, the thickness of the conductive blocks disclosed in the present disclosure is not limited by the substrate or electroplating, has better flexibility, and is free from the limitation that the patterning position of the conductive layer must avoid the position of the conductive blocks, thereby providing more diverse design variations for circuit patterns.

[0069] Although the present disclosure has been described in detail with respect to certain embodiments, other embodiments are possible. Therefore, the spirit and scope of the appended claims should not be limited to the embodiments described herein.

Claims

1. A circuit board, characterized in that: Include: a first conductive layer; At least one adhesive layer is disposed on the surface of the first conductive layer, the at least one adhesive layer comprises a transient liquid phase sintering adhesive material, the transient liquid phase sintering adhesive material comprises copper and tin, and the resistivity of the at least one adhesive layer is less than 1×10 -6 Ω·m and thermal conductivity greater than 20W / mk; At least one conductive block, comprising a top surface and a bottom surface opposite to the top surface, wherein the bottom surface contacts the at least one adhesive layer and is bonded to the first conductive layer via the at least one adhesive layer, wherein the at least one conductive block is a plurality of conductive blocks, and the plurality of conductive blocks are of different sizes, shapes, or both sizes and shapes, wherein the at least one adhesive layer is bonded to the first conductive layer by heating the transient liquid phase sintering adhesive material to make the transient liquid phase sintering adhesive material in a liquid phase flow state; An insulating layer covering the surface of the first conductive layer and the at least one conductive block; as well as The second conductive layer is disposed on the insulating layer.

2. The circuit board according to claim 1, characterized in that: The ratio of the thickness of the first conductive layer to the thickness of the first conductive layer, the at least one adhesive layer and the at least one conductive block is 1:15 to 1:

30.

3. The circuit board according to claim 1, characterized in that: The total thickness of the first conductive layer, the at least one adhesive layer and the at least one conductive block is 20 micrometers to 3 millimeters.

4. The circuit board according to claim 1, characterized in that: The thickness of the first conductive layer is greater than 3 microns.

5. The circuit board according to claim 1, characterized in that: The thickness of the at least one adhesive layer is less than 5 microns.

6. The circuit board according to claim 1, characterized in that: The surface area of ​​the bottom surface of the at least one conductive block contacted by the at least one adhesive layer does not exceed the surface area of ​​the bottom surface of the at least one conductive block.

7. The circuit board according to claim 1, characterized in that: The invention further comprises at least one conductive column, which penetrates the second conductive layer and the insulating layer and extends to the top surface of the at least one conductive block.

8. The circuit board according to claim 7, characterized in that: The top of the at least one conductive column is coplanar with the second conductive layer.

9. The circuit board according to claim 7, characterized in that: The at least one conductive column is a conductive column, and the conductive column is located on one of the plurality of conductive blocks.

10. The circuit board according to claim 7, characterized in that: The at least one conductive column is a plurality of conductive columns, and the plurality of conductive columns are located on one of the plurality of conductive blocks.

11. The circuit board according to claim 1, characterized in that: The first conductive layer is a patterned first conductive layer, the second conductive layer is a patterned second conductive layer or a combination thereof.

12. The circuit board according to claim 1, characterized in that: The copper and the tin are in the form of metal particles.

13. A method for manufacturing a circuit board, characterized in that: Include: providing a first conductive layer; Providing an adhesive material and at least one conductive block, wherein the adhesive material comprises a transient liquid phase sintering adhesive material, the transient liquid phase sintering adhesive material comprises copper and tin, and the at least one conductive block is a plurality of conductive blocks, and the plurality of conductive blocks are of different sizes, different shapes, or different sizes and shapes; The adhesive material is used to bond the at least one conductive block to the surface of the first conductive layer, comprising heating the adhesive material to make the transient liquid phase sintering adhesive material in a liquid phase flow state, and then bonding the at least one conductive block to the surface of the first conductive layer using the adhesive material, wherein the resistivity of the adhesive layer formed by the transient liquid phase sintering adhesive material is less than 1x10 -6 Ω·m and thermal conductivity greater than 20W / mk; Provide insulation; Disposing the insulating layer on the surface of the first conductive layer and on the at least one conductive block; as well as A second conductive layer is disposed on the insulating layer.

14. The method according to claim 13, characterized in that The step of disposing the insulating layer on the surface of the first conductive layer and on the at least one conductive block comprises: removing a portion of the insulating layer to form at least one groove recessed upward, covering and accommodating the at least one conductive block in the at least one groove; and The insulating layer, the at least one conductive block and the first conductive layer are laminated.

15. The method according to claim 13, characterized in that The method further includes forming at least one conductive column, wherein the at least one conductive column penetrates the second conductive layer and the insulating layer and extends to the top surface of the at least one conductive block.

16. The method according to claim 15, characterized in that The step of forming the at least one conductive column comprises: removing a portion of the insulating layer and a portion of the second conductive layer to expose the top surface of the at least one conductive block and form at least one blind hole; as well as The at least one blind hole is filled with a conductive material so that the conductive material contacts the second conductive layer to form the at least one conductive column.

17. The method according to claim 13, characterized in that After the step of disposing the second conductive layer on the insulating layer, the method further includes patterning the first conductive layer and the second conductive layer.

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