TWI837936B - Heat-conductive circuit board - Google Patents

Abstract

The present invention provides a heat-conductive circuit board, which includes a board, a plurality of heat-conductive pads, a plurality of heat-conductive pillars, and a metal layer. The board includes an insulating layer, a top conductive layer, and a bottom conductive layer, the latter two of which are respectively formed on two opposite sides of the insulating layer. The board has a plurality of receiving slots recessing from the top conductive layer to the insulating layer and a plurality of thru-holes that are recessed from the bottom conductive layer to the receiving slots. The heat-conductive pads are respectively formed in the receiving slots. The heat-conductive pillars are respectively filled in the thru-holes and are respectively connected to the heat-conductive pads. The metal layer is formed on the bottom conductive layer, and is connected to the heat-conductive pillars. Each of the receiving slots is configured to provide an electronic component to be accommodated therein and to be in contact with the corresponding heat-conductive pads.

Description

Thermally Conductive Circuit Board

The present invention relates to a carrier board, and more particularly to a heat-conducting circuit carrier board without embedded electronic components.

Based on the development of semiconductor technology, the requirements for heat dissipation efficiency of electronic components mounted on circuit boards are gradually increasing. Therefore, the industry often needs to embed the corresponding electronic components in the existing circuit boards according to the needs of downstream, and dissipate the heat of the electronic components through the corresponding heat-conducting structure. However, the embedding and corresponding processing of electronic components in existing circuit boards not only require technology and equipment, but also the existing circuit boards are equivalent to customized products and are difficult to be widely used. This has formed a certain threshold for manufacturers who want to enter this field, thereby invisibly reducing the development and promotion of the industry.

Therefore, the inventors of the present invention believe that the above defects can be improved, and have conducted intensive research and applied scientific principles to finally propose the present invention which has a reasonable design and effectively improves the above defects.

The present invention provides a heat-conducting circuit substrate, which can effectively improve the defects that may be produced by the existing circuit substrate.

The present invention discloses a heat-conducting circuit carrier, which includes: a circuit board, including: an insulating layer; a top conductive layer, formed on one side of the insulating layer; a bottom conductive layer, formed on the other side of the insulating layer; and at least one circuit layer, buried in the insulating layer; wherein the circuit board has a plurality of component placement grooves formed from the top conductive layer toward the insulating layer, and a plurality of through holes formed from the bottom conductive layer to the bottom of the plurality of component placement grooves, and the bottom of each component placement groove is spaced a preset distance from the bottom conductive layer; a plurality of thermal pads , respectively formed on the bottom of the plurality of component slots; a plurality of heat-conducting columns, respectively filling the plurality of through holes and respectively connected to the plurality of heat-conducting pads; and a metal layer, in sheet form and formed on the bottom conductive layer, and the metal layer is connected to the plurality of heat-conducting columns; wherein any of the component slots of the thermally conductive circuit carrier can be used for at least part of an electronic component to be accommodated therein and abut against the corresponding heat-conducting pad, so that the heat energy generated by the electronic component is transferred to the external space through the corresponding heat-conducting pad, the plurality of heat-conducting columns, and the metal layer.

The present invention also discloses a heat-conducting circuit carrier, comprising: a circuit board, including: an insulating layer; a top conductive layer formed on one side of the insulating layer; a bottom conductive layer formed on the other side of the insulating layer; and at least one circuit layer buried in the insulating layer; wherein the circuit board has a component placement groove formed from the top conductive layer toward the insulating layer, and a plurality of through holes formed from the bottom conductive layer and connected to the bottom of the component placement groove, and the bottom of the component placement groove is spaced a preset distance from the bottom conductive layer. distance; a thermal pad formed at the bottom of the component slot; a plurality of thermally conductive columns respectively filling the plurality of through holes and connected to the thermal pad; and a metal layer in sheet form formed on the bottom conductive layer, and the metal layer connected to the plurality of thermally conductive columns; wherein the component slot of the thermally conductive circuit carrier can be used to accommodate at least a portion of an electronic component therein and abut against the thermally conductive pad, so that the heat energy generated by the electronic component is transferred to the external space through the thermally conductive pad, the plurality of thermally conductive columns, and the metal layer.

In summary, the thermally conductive circuit carrier disclosed in the embodiment of the present invention has a component placement slot that does not limit the type of electronic components that can be accommodated, and the top conductive layer and the bottom conductive layer can form a corresponding circuit layout according to the type of electronic components. In other words, the thermally conductive circuit carrier has a wide range of applications, which is conducive to improving its commonality or circulation, thereby effectively reducing the overall production cost.

To further understand the features and technical contents of the present invention, please refer to the following detailed description and drawings of the present invention. However, such description and drawings are only used to illustrate the present invention and do not limit the protection scope of the present invention.

The following is an explanation of the implementation of the "thermal conductive circuit substrate" disclosed in the present invention through specific concrete embodiments. Those skilled in the art can understand the advantages and effects of the present invention from the contents disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and the details in this specification can also be modified and changed in various ways based on different viewpoints and applications without deviating from the concept of the present invention. In addition, the drawings of the present invention are only for simple schematic illustrations and are not depicted according to actual sizes. Please note in advance. The following implementation will further explain the relevant technical contents of the present invention in detail, but the disclosed contents are not intended to limit the scope of protection of the present invention.

It should be understood that, although the terms "first", "second", "third", etc. may be used in this document to describe various components or signals, these components or signals should not be limited by these terms. These terms are mainly used to distinguish one component from another component, or one signal from another signal. In addition, the term "or" used in this document may include any one or more combinations of the related listed items depending on the actual situation.

[Example 1]

Please refer to FIG. 1 to FIG. 7 , which are the first embodiment of the present invention. As shown in FIG. 1 to FIG. 3 , this embodiment discloses a heat-conducting circuit carrier 100, which does not have any electronic components embedded therein. In other words, the heat-conducting circuit carrier 100 in this embodiment excludes any circuit board with electronic components embedded therein.

As shown in FIG. 4 , the thermally conductive circuit carrier 100 in this embodiment includes a circuit board 1, a plurality of thermally conductive pads 2 located in the circuit board 1, a plurality of thermally conductive pillars 3 extending from the plurality of thermally conductive pads 2, a metal layer 4 located on one side of the circuit board 1 and connected to the plurality of thermally conductive pillars 3, and an electroplating layer 5 located on the other side of the circuit board 1, but the present invention is not limited thereto. For example, in other embodiments not shown in the present invention, the electroplating layer 5 may be omitted or replaced by other structures according to design requirements. The following is a description of the component structures and connection relationships of the thermally conductive circuit carrier 100.

In this embodiment, the circuit board 1 includes an insulating layer 11, at least one circuit layer 12 embedded in the insulating layer 11, a top conductive layer 13 formed on one side (e.g., top side) of the insulating layer 11, and a bottom conductive layer 14 formed on the other side (e.g., bottom side) of the insulating layer 11. Preferably, the number of at least one circuit layer 12 is multiple and is spaced apart from each other along the thickness direction T, and the thickness of the top conductive layer 13 is substantially equal to the thickness of the bottom conductive layer 14 and less than the thickness of the insulating layer 11, but the present invention is not limited thereto.

More specifically, the circuit board 1 has a plurality of component slots S formed from the top conductive layer 13 toward the insulating layer 11, and a plurality of through holes H formed from the bottom conductive layer 14 and connected to the slot bottoms S1 of the plurality of component slots S. The slot bottom S1 of each component slot S is spaced from the bottom conductive layer 14 by a preset distance DS1, thereby preventing the component slot S from penetrating or exposing the bottom conductive layer 14. In other words, any groove that is penetrating or has a conductive layer as the slot bottom is different from the component slot S referred to in this embodiment.

Furthermore, each of the slots S does not touch at least one of the circuit layers 12 (that is, the sidewall S2 of each of the slots S preferably does not expose any circuit layer 12; or in other words, the formation of each of the slots S does not damage any circuit layer 12), and the preset distance DS1 is preferably at least greater than 2 mils.

The depths of the plurality of slots S (or the plurality of preset distances DS1) are illustrated as having the same value in FIG. 4 , but the specific shapes and actual depths of the plurality of slots S can be adjusted and varied according to design requirements (e.g., the slots S can be square slots or round slots and the depth can be 20 mils). For example, as shown in FIG. 5 , the circuit board 1 can be formed with a plurality of slots S having different depths (that is, the plurality of slots S corresponding to the plurality of preset distances DS1 of the bottom conductive layer 14 include at least two different values) to meet a wider range of requirements.

Accordingly, the thermally conductive circuit carrier 100 in this embodiment does not limit the type of electronic components (not shown) that can be accommodated by the component placement slots S, and the top conductive layer 13 and the bottom conductive layer 14 can form corresponding circuit layouts according to the types of the electronic components. In other words, the thermally conductive circuit carrier 100 has a wider range of applications, which is conducive to improving its commonality or circulation, thereby effectively reducing the overall production cost.

The plurality of heat-conducting pads 2 are respectively formed on the groove bottoms S1 of the plurality of the mounting grooves S (that is, the groove bottom S1 of each mounting groove S is provided with one heat-conducting pad 2), and each of the heat-conducting pads 2 in this embodiment does not contact the side wall S2 of the corresponding mounting groove S to form an annular explosion-proof groove S3 between each other, and the width WS3 of the annular explosion-proof groove S3 is preferably at least 0.5 millimeters (mm), but the specific value of the width WS3 can be adjusted and varied according to actual needs and is not limited here.

Accordingly, the thermally conductive circuit carrier 100 disclosed in the present embodiment forms the annular explosion-proof groove S3 to separate the corresponding thermally conductive pad 2 from the side wall S2 of the mounting groove S, so as to prevent heat energy from being quickly transferred from any of the thermally conductive pads 2 to the insulating layer 11, thereby effectively reducing the probability of the thermally conductive circuit carrier 100 exploding or delaminating.

In more detail, each of the thermal pads 2 in this embodiment adopts a double-layer structure, which includes a first layer 21 and a second layer 22 stacked on the first layer 21. The first layer 21 of each of the thermal pads 2 is formed on the bottom S1 of the slot corresponding to the component placement slot S and connected to a plurality of the thermally conductive columns 3, and the edge of the second layer 22 is aligned with the edge of the first layer 21 and is used for the electronic components to be mounted thereon.

Furthermore, the materials of the first layer 21 and the second layer 22 of each of the thermal pads 2 can be the same material or different materials according to design requirements (e.g., the first layer 21 is made of a material suitable for bonding to the insulating layer 11, and the second layer 22 is made of a material suitable for welding the electronic components), and the present invention is not limited thereto.

The plurality of thermally conductive columns 3 are respectively filled in the plurality of through holes H and are respectively connected to the plurality of thermally conductive pads 2, the metal layer 4 is formed on the bottom conductive layer 14, and the metal layer 4 is connected to the plurality of thermally conductive columns 3. In other words, one end of each thermally conductive column 3 is buried in the insulating layer 11 and connected to the corresponding thermally conductive pad 2, and the other end of each thermally conductive column 3 is buried in the bottom conductive layer 14 and connected to the metal layer 4.

In this embodiment, any of the heat-conducting columns 3 is truncated and its cross-sectional area gradually increases from the heat-conducting pad 2 toward the metal layer 4 (or away from the heat-conducting pad 2), so that heat energy can be smoothly transferred outward from any of the heat-conducting pads 2. Furthermore, the thickness of each of the heat-conducting pads 2 is greater than the thickness of the metal layer 4 (e.g., the thickness of the second layer 22 is equal to the thickness of the metal layer 4), but the present invention is not limited thereto.

As described above, each of the mounting slots S of the thermally conductive circuit carrier 100 in this embodiment can be used to accommodate at least a portion of the electronic component therein to abut against the corresponding thermal pad 2, so that the heat energy generated by the electronic component can be transferred to the external space through the corresponding thermal pad 2, the plurality of thermally conductive pillars 3, and the metal layer 4.

Furthermore, the plurality of mounting slots S that share the metal layer 4 in this embodiment are not limited to being used only for arranging heat-generating electronic components; for example, in other embodiments not shown in the present invention, one of the mounting slots S can accommodate a heat-generating electronic component, while another mounting slot S accommodates an object used for heat dissipation, so that the heat energy generated by the electronic component can be effectively absorbed through the metal layer 4.

Furthermore, the metal layer 4 is in sheet form in this embodiment, and a projection area formed by orthographically projecting the plurality of thermal pads 2 toward the metal layer 4 is located within an outer contour of the metal layer 4. Accordingly, as shown in FIG6 , the thermally conductive circuit carrier 100 may further include a heat sink fin 6 selectively fixed to the metal layer 4 to further enhance the heat dissipation performance of the thermally conductive circuit carrier 100.

In addition, the electroplating layer 5 is formed on the top conductive layer 13, and the thickness of the electroplating layer 5 is preferably equal to the thickness of the metal layer 4, so that the metal layer 4 and the electroplating layer 5 are formed in the same electroplating process.

It should be further explained that at least one of the circuit layers 12, the top conductive layer 13, the bottom conductive layer 14, the plurality of thermal conductive pads 2, the plurality of thermal conductive pillars 3, the electroplating layer 5, and the metal layer 4 in this embodiment may be made of the same material (e.g., copper) or different materials according to design requirements.

[Example 2]

Please refer to FIG. 7 and FIG. 8 , which are the second embodiment of the present invention. Since this embodiment is similar to the first embodiment, the similarities between the two embodiments will not be described in detail, and the differences between this embodiment and the first embodiment are roughly described as follows:

In this embodiment, the thermally conductive circuit carrier 100 can be recessed from the top conductive layer 13 of the circuit board 1 toward the insulating layer 11 to form at least one mounting slot S, and the thermally conductive circuit carrier 100 can further be recessed from the bottom conductive layer 14 toward the insulating layer 11 to form at least one mounting slot S', which is also equipped with a thermally conductive pad 2' located inside, a plurality of thermally conductive columns 3' connected to the thermally conductive pad 2', and a metal layer 4' formed on the top conductive layer 13 and respectively connected to the plurality of thermally conductive columns 3'.

As described above, the thermally conductive circuit carrier 100 in this embodiment can provide a more diverse structural design by forming at least one mounting slot S, S' on different sides thereof, thereby being able to meet more diverse requirements, thereby facilitating the improvement of the commonality or circulation of the thermally conductive circuit carrier 100.

[Technical Effects of the Embodiments of the Invention]

In summary, the thermally conductive circuit carrier disclosed in the embodiment of the present invention has a component placement slot that does not limit the type of electronic components that can be accommodated, and the top conductive layer and the bottom conductive layer can form a corresponding circuit layout according to the type of electronic components. In other words, the thermally conductive circuit carrier has a wide range of applications, which is conducive to improving its commonality or circulation, thereby effectively reducing the overall production cost.

Furthermore, the thermally conductive circuit carrier disclosed in the embodiment of the present invention is separated from each other by forming the annular explosion-proof groove between any of the thermally conductive pads and the side wall of the corresponding mounting groove to prevent heat energy from being quickly transferred from any of the thermally conductive pads to the insulating layer, thereby effectively reducing the probability of the thermally conductive circuit carrier exploding or delaminating.

The above disclosed contents are only preferred feasible embodiments of the present invention and are not intended to limit the patent scope of the present invention. Therefore, all equivalent technical changes made by using the contents of the specification and drawings of the present invention are included in the patent scope of the present invention.

100: Thermally conductive circuit board 1: Circuit board 11: Insulation layer 12: Circuit layer 13: Top conductive layer 14: Bottom conductive layer 2, 2': Thermal pad 21: First layer 22: Second layer 3, 3': Thermal column 4, 4': Metal layer 5: Electroplating layer 6: Heat sink S, S': Component slot S1: Slot bottom S2: Side wall S3: Annular explosion-proof slot H: Perforation T: Thickness direction DS1: Default distance WS3: Width

FIG. 1 is a three-dimensional schematic diagram of a thermally conductive circuit carrier according to a first embodiment of the present invention.

FIG. 2 is a schematic top view of FIG. 1 .

FIG. 3 is a schematic bottom view of FIG. 1 .

FIG. 4 is a schematic cross-sectional view along section line IV-IV of FIG. 1 .

FIG. 5 is a schematic diagram showing a variation of FIG. 4 .

FIG. 6 is a schematic diagram of FIG. 4 with heat dissipation fins added.

FIG. 7 is a three-dimensional schematic diagram of a heat-conducting circuit carrier according to the second embodiment of the present invention.

FIG. 8 is a schematic cross-sectional view along section line VIII-VIII of FIG. 7 .

100: Thermally conductive circuit substrate

1: Circuit board

11: Insulating layer

12: Circuit layer

13: Top conductive layer

14: Bottom conductive layer

2: Thermal pad

21: First level

22: Second level

3: Thermal conductivity column

4:Metal layer

5: Electroplating

S: Parts slot

S1: Tank bottom

S2: Side wall

S3: Annular explosion-proof groove

H: Perforation

T: thickness direction

DS1: Default distance

WS3: Width

Claims (9)

A heat-conducting circuit carrier comprises: a circuit board including: an insulating layer; a top conductive layer formed on one side of the insulating layer; a bottom conductive layer formed on the other side of the insulating layer; and at least one circuit layer buried in the insulating layer; wherein the circuit board is formed with a plurality of recesses from the top conductive layer toward the insulating layer. The bottom conductive layer is provided with a plurality of through holes connected to the bottom of the plurality of the component placement slots, and the bottom of each of the component placement slots is spaced apart from the bottom conductive layer by a preset distance; a plurality of thermal conductive pads are respectively formed on the bottom of the plurality of component placement slots; a plurality of thermal conductive columns are respectively filled in the plurality of through holes and respectively connected to the bottom of the plurality of the component placement slots; connected to the plurality of thermal pads; and a metal layer in sheet form and formed on the bottom conductive layer, and the metal layer is connected to the plurality of thermal conductive pillars; wherein any of the mounting slots of the thermally conductive circuit carrier can be used to accommodate at least a portion of an electronic component therein and abut against the corresponding thermal pad, so that the heat energy generated by the electronic component is transferred to the external space through the corresponding thermal pad, the plurality of thermal conductive pillars, and the metal layer; wherein, in each of the mounting slots, the thermal pad does not contact the side wall of the mounting slot to form an annular explosion-proof groove between them, and the width of the annular explosion-proof groove is at least 0.5 mm. A thermally conductive circuit carrier as described in claim 1, wherein each of the component placement slots does not touch at least one of the circuit layers, and the preset distance is at least greater than 2 mils. The thermally conductive circuit carrier as described in claim 2, wherein the plurality of preset distances corresponding to the plurality of component slots on the bottom conductive layer include at least two different values. The heat-conductive circuit carrier as described in claim 1, wherein each of the heat-conductive pads comprises: a first layer formed on the bottom of the slot corresponding to the mounting slot and connected to a plurality of the heat-conductive pillars; and a second layer stacked on the first layer, and the thickness of the second layer is equal to the thickness of the metal layer. A thermally conductive circuit carrier as described in claim 4, wherein the materials of the first layer and the second layer of each thermally conductive pad are different from each other. As described in claim 1, the heat-conducting circuit carrier, wherein any of the heat-conducting pillars is in a truncated cone shape and the area of its cross section gradually increases from the direction corresponding to the heat-conducting pad toward the metal layer. The thermally conductive circuit carrier as described in claim 1, wherein the thermally conductive circuit carrier further includes an electroplating layer formed on the top conductive layer, and the thickness of the electroplating layer is equal to the thickness of the metal layer. A thermally conductive circuit carrier as described in claim 1, wherein the thermally conductive circuit carrier further comprises a heat sink selectively fixed to the metal layer. A heat-conducting circuit carrier comprises: a circuit board, comprising: an insulating layer; a top conductive layer, formed on one side of the insulating layer; a bottom conductive layer, formed on the other side of the insulating layer; and at least one circuit layer, buried in the insulating layer; wherein the circuit board has a component placement groove formed from the top conductive layer toward the insulating layer, and a plurality of through holes, which are formed from the bottom conductive layer and are connected to the bottom of the component placement groove, and the bottom of the component placement groove is separated from the bottom conductive layer by a preset distance; a heat-conducting pad, formed on the bottom of the component placement groove; a plurality of heat-conducting columns, which are respectively filled in the plurality of through holes and are connected to the bottom of the component placement groove; connected to the thermal pad; and a metal layer in sheet form and formed on the bottom conductive layer, and the metal layer is connected to the plurality of thermally conductive pillars; wherein the component placement slot of the thermally conductive circuit carrier can be used to accommodate at least part of an electronic component therein and abut against the thermally conductive pad, so that the heat energy generated by the electronic component is transferred to the external space through the thermally conductive pad, the plurality of thermally conductive pillars, and the metal layer; wherein, in the component placement slot, the thermally conductive pad does not contact the side wall of the component placement slot to form an annular explosion-proof slot between them, and the width of the annular explosion-proof slot is at least 0.5 mm.

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