CN217037540U - Circuit board with embedded device heat radiation structure - Google Patents

Abstract

The utility model provides a circuit board with a heat dissipation structure of an embedded device, which comprises a circuit board heat dissipation structure, at least one electronic device and a circuit board circuit structure. The circuit board heat dissipation structure comprises at least one opening and at least one heat dissipation block, wherein the heat dissipation block is arranged in the opening and is provided with a first surface and a second surface. The electronic device is arranged on the heat dissipation block and is in contact with the first surface of the heat dissipation block. The circuit board circuit structure is arranged on the circuit board heat dissipation structure and covers the electronic device; the second surface of the heat dissipation block is exposed in the opening. The circuit board with the embedded device heat dissipation structure is in contact with the electronic device through one surface, and the other surface of the circuit board is exposed out of the heat dissipation block in the opening to conduct and dissipate heat energy generated by the electronic device, so that the effect of rapid heat dissipation is further achieved.

Description

Circuit board with embedded device heat radiation structure

Technical Field

The present invention relates to a heat dissipation structure, and more particularly, to a circuit board with a heat dissipation structure having embedded components.

Background

Please refer to fig. 3A to 3N, which are process flow diagrams of the structure of the embedded device of the conventional circuit board. As shown in fig. 3A, a copper foil substrate 20 is provided, wherein the copper foil substrate 20 has an upper surface 201 and a lower surface 202. As shown in fig. 3B, a first upper circuit layer 21A and a first lower circuit layer 21B are provided on the upper surface 201 and the lower surface 202 of the copper foil substrate 20, respectively. As shown in fig. 3C, an opening H is formed in the copper foil substrate 20. As shown in fig. 3D, an adhesive layer 22 is disposed on the lower surface 202 of the copper foil substrate 20 and covers one end of the opening H, such that the opening H forms a groove S. As shown in fig. 3E, an electronic device C is disposed in the recess S. As shown in fig. 3F, a first upper dielectric layer 23A is disposed on the upper surface 201 of the copper foil substrate 20, and covers the first upper circuit layer 21A and the electronic device C. As shown in fig. 3G, the adhesive layer 22 is removed. As shown in fig. 3H, a first lower dielectric layer 23B is disposed on the lower surface 202 of the copper foil substrate 20. As shown in fig. 3I, at least one first upper via 23A1 and at least one first lower via 23B1 are formed on the surfaces of the first upper dielectric layer 23A and the first lower dielectric layer 23B, respectively, to expose a portion of the first upper circuit layer 21A and the first lower circuit layer 21B. As shown in fig. 3J, a second upper circuit layer 24A and a second lower circuit layer 24B are formed in the at least one first upper via 23A1 and the at least one first lower via 23B1, respectively, and on the surfaces of the first upper dielectric layer 23A and the first lower dielectric layer 23B. As shown in fig. 3K, a second upper dielectric layer 25A and a second lower dielectric layer 25B are formed on the surfaces of the first upper dielectric layer 23A and the first lower dielectric layer 23B, respectively. As shown in fig. 3L, at least one second upper via 25A1 and at least one second lower via 25B1 are formed on the surfaces of the second upper dielectric layer 25A and the second lower dielectric layer 25B, respectively, to expose portions of the second upper circuit layer 24A and the second lower circuit layer 24B. As shown in fig. 3M, a third upper circuit layer 26A and a third lower circuit layer 26B are formed in the at least one second upper via 25A1 and the at least one second lower via 25B1, and on the surfaces of the second upper dielectric layer 25A and the second lower dielectric layer 25B, respectively. As shown in fig. 3N, a first insulating passivation layer 27A and a second insulating passivation layer 27B are formed on the surfaces of the second upper dielectric layer 25A and the second lower dielectric layer 25B, respectively, to expose a portion of the third upper circuit layer 26A and the third lower circuit layer 26B. Thus, the circuit board embedded device structure 2 is completed.

Please refer to fig. 3O, which is a schematic heat dissipation diagram of the embedded device structure of the circuit board of fig. 3N. As can be seen from the finally completed structure diagram of the circuit board embedded device in fig. 3N, since the electronic device C is completely covered and wrapped in the circuit board embedded device structure 2, and the copper foil substrate 20, the first upper dielectric layer 23A and the first lower dielectric layer 23B which are in direct contact with the surface of the electronic device C do not have a high thermal conductivity coefficient, the heat generated by the electronic device C cannot be smoothly discharged out of the circuit board embedded device structure 2, and the heat dissipation direction thereof is wrapped in the circuit board embedded device structure 2 as indicated by an arrow mark.

Moreover, although the electrical connection points of the electronic device C are connected to the first upper circuit layer 21A, the second upper circuit layer 24A and the third upper circuit layer 26A, and a portion of the third upper circuit layer 26A is exposed out of the first insulating protection layer 27A, the path of the circuit connection is tortuous, and the contact area with the surface of the electronic device C is too small, so that a good heat dissipation effect cannot be achieved.

Therefore, how to provide a circuit board with a heat dissipation structure of embedded devices to solve the above problems has become an urgent issue to be studied.

SUMMERY OF THE UTILITY MODEL

In view of the above problems, the present invention provides a circuit board with a heat dissipation structure of embedded devices, which includes a heat dissipation structure of circuit board, at least one electronic device and a circuit structure of circuit board. The circuit board heat dissipation structure comprises at least one opening and at least one heat dissipation block, wherein the heat dissipation block is arranged in the opening and is provided with a first surface and a second surface. The electronic device is arranged on the heat dissipation block and is in contact with the first surface of the heat dissipation block. The circuit board circuit structure is arranged on the circuit board heat dissipation structure and wraps the electronic device; the second surface of the heat dissipation block is exposed in the opening.

As described above, the circuit board with the heat dissipation structure of the embedded device of the present invention further achieves the effect of rapid heat dissipation by the heat dissipation block, one surface of which is in contact with the electronic device and the other surface of which is exposed in the opening, conducting and dissipating heat generated by the electronic device. Besides, the heat dissipation of the heat dissipation block is realized, and the heat generated by the electronic device can be conducted and dissipated by the protruding part protruding out of the side surface of the circuit board with the embedded device heat dissipation structure. Moreover, even if a plurality of electronic devices are required to be arranged at the same time, the effect of heat dissipation at the same time can be achieved through the arrangement of the circuit board with the embedded device heat dissipation structure.

Drawings

FIGS. 1A to 1L are flow charts of processes for fabricating a circuit board with a heat dissipation structure of an embedded device according to the present invention;

FIGS. 2A and 2B are a cross-sectional view and a top view of a circuit board with a heat dissipation structure of an embedded device according to the present invention;

FIGS. 3A to 3N are process flow diagrams illustrating a conventional embedded device structure of a circuit board;

fig. 3O is a schematic diagram of heat dissipation of the embedded device structure of the circuit board of fig. 3N.

Detailed Description

Fig. 1A to fig. 1L are process flow diagrams of manufacturing a circuit board with a heat dissipation structure of an embedded device according to the present invention. As shown in fig. 1A, a copper clad substrate 10 is provided, the copper clad substrate 10 includes a first surface and a second surface opposite to the first surface, the first surface is located above the second surface, and a releasing layer 101 and a copper foil layer 102 are sequentially disposed on the first surface and the second surface. As shown in fig. 1B, a first circuit layer 11 is disposed on a copper foil layer 102 of a copper foil substrate 10, and a portion of the first circuit layer 11 is etched (etching) to form at least one recess S. It should be noted that, in the embodiment of the present invention, corresponding circuit structures are respectively formed on the first surface and the second surface of the copper foil substrate 10, and therefore, the corresponding structures are still drawn in the drawings, but for simplifying the description, only the circuit structures formed on the first surface of the copper foil substrate 10 are described and labeled in the following process flows. As shown in fig. 1C, at least one electronic device C is disposed in the at least one recess S. As shown in fig. 1D, a first dielectric layer 12 is disposed on the copper foil layer 102 and covers the first circuit layer 11 and the at least one electronic device C, wherein the first circuit layer 11 and the first dielectric layer 12 form a first circuit layer structure. As shown in fig. 1E, a second circuit layer structure and a third circuit layer 15 are sequentially formed on the first circuit layer structure to form a circuit board structure a, wherein the second circuit layer structure includes a second circuit layer 13 and a second dielectric layer 14, an insulating protection layer 16 is disposed on the second dielectric layer 14, the insulating protection layer 16 covers a portion of the third circuit layer 15 and exposes another portion of the third circuit layer 15, and a material of the insulating protection layer 16 includes solder resist ink (solder resist ink). The processes for forming the second circuit layer structure and the third circuit layer 15 are as described in the prior art, and are not described herein again. As shown in fig. 1F, the circuit board structure a is separated from the release layer 101 of the copper foil substrate 10. As shown in fig. 1G, the patterning of the circuit layer on the lower surface of the circuit board structure a includes disposing an isolation layer 17 on the lower surface of the circuit board structure a, that is, disposing the isolation layer 17 on the copper foil layer 102 of the circuit board structure a. As shown in fig. 1H, the lower surface of the circuit board structure a is etched to remove a portion of the copper foil layer 102, and after at least one copper foil opening O is formed, the isolation layer 17 is removed. As shown in fig. 1I, an adhesive layer 18 is disposed in the copper foil opening O. As shown in fig. 1J, a predetermined depth of cutting is performed on a positioning point P of the circuit board structure a to form a positioning groove, wherein the positioning groove is formed by laser cutting to cut off each layer of devices in the positioning groove, and only the copper foil layer 102 is left at the bottom of the positioning groove, so that the circuit board structure a is separated into a circuit board circuit structure a1 and a circuit board heat dissipation structure a2 by the positioning groove. As shown in fig. 1K, the copper foil layer 102 at the bottom of the positioning groove is used as a turning point, and the circuit board heat dissipation structure a2 is turned over, so that the circuit board heat dissipation structure a2 is located below the circuit board circuit structure a 1. As shown in fig. 1L, after the circuit board heat dissipation structure a2 is turned over, the lower surface of the circuit board heat dissipation structure a2 is butted and covered on the lower surface of the circuit board wiring structure a1 by the circuit butting technique and the adhesive layer 18, and the electronic device C is embedded in the circuit board structure a, that is, the electronic device C is embedded in the circuit board wiring structure a1 and the circuit board heat dissipation structure a2, thereby completing the circuit board 1 having the embedded device heat dissipation structure, wherein the circuit board 1 having the embedded device heat dissipation structure includes the circuit board wiring structure a1 and the circuit board heat dissipation structure a2, the circuit board heat dissipation structure a2 includes a heat dissipation block D, the heat dissipation block D is composed of a first wiring layer 11, a second wiring layer 13 and a third wiring layer 15, the heat dissipation block D has a first surface D1 and a second surface D2, the electronic device C is disposed on the first surface D1 of the heat dissipation block D and is in contact with the first surface D1, the second surface D2 of the heat slug D is exposed in the opening H of the circuit board heat dissipation structure a 2.

In addition, in the process of fig. 1J, the positioning points of the first circuit board structure a are cut, and the ductility of the first circuit layer 11 is utilized to facilitate the subsequent positioning when the circuit board heat dissipation structure a2 is flipped over. In another embodiment of the present invention, the positioning points may be used to cut the circuit board circuit structure a1 and the circuit board heat dissipation structure a2, and then perform the butting positioning operation.

Furthermore, in the process of fig. 1J, since the circuit board heat dissipation structure a2 is the butted circuit board circuit structure a1 flipped over by the ductility of the first circuit layer 11, after the circuit board heat dissipation structure a2 flips over the butted circuit board circuit structure a1, the first circuit layer 11 protrudes from the side of the whole circuit board 1 having the heat dissipation structure with embedded devices to form a protruding portion 19, as shown in fig. 1L.

In addition, in the process of fig. 1J, since the circuit board heat dissipation structure a2 is connected to the circuit board wiring structure a1 in an inverted manner, a predetermined location point P is preset in the whole circuit board 1 with the embedded device heat dissipation structure, and the left and right positions of the connection point (wiring layer) to be connected are configured, so that after the circuit board heat dissipation structure a2 is inverted, the corresponding relationship between the upper and lower positions and the circuit board wiring structure a1 is formed. Alternatively, in the case where the circuit layer of the circuit board circuit structure a1 and the circuit layer of the circuit board heat dissipation structure a2 do not need to be vertically butted, the circuit layer of the circuit board circuit structure a1 and the circuit layer of the circuit board heat dissipation structure a2 are separated by the adhesive layer 18.

As described above, in the process of fig. 1I, if the first circuit layer 11 preset in the circuit board heat dissipation structure a2 does not need to be butted with the first circuit layer 11 of the circuit board circuit structure a1, the first circuit layer 11 of the circuit board heat dissipation structure a2 and the first circuit layer 11 of the circuit board circuit structure a1 are isolated by disposing and adhering the adhesive layer 18 between the circuit board heat dissipation structure a2 and the circuit board circuit structure a 1.

In the process of fig. 1J, if the first circuit layer 11 of the circuit board heat dissipation structure a2 is required to be connected to the first circuit layer 11 of the circuit board circuit structure a1, the adhesive layer 18 is disposed in the copper foil opening O around the first circuit layer 11 of the circuit board heat dissipation structure a2 and in the copper foil opening O around the first circuit layer 11 of the circuit board circuit structure a1, so as to electrically connect the first circuit layer 11 of the circuit board heat dissipation structure a2 and the first circuit layer 11 of the circuit board circuit structure a 1.

In addition, in the process of fig. 1L, the area of the second surface D2 of the heat slug D is larger than the surface area of the electronic device C, so that when the electronic device C contacts with the first surface D1 of the heat slug D, the heat generated by the electronic device C can be conducted to the outside of the circuit board 1 having the heat dissipation structure of the embedded device through the first circuit layer 11, the second circuit layer 13 and the three circuit layers 15.

As described above, the heat dissipation block D is formed by stacking the first circuit layer 11, the second circuit layer 13 and the third circuit layer 15 in the circuit board structure a, and contacts with the surface of the electronic device C to achieve the heat dissipation effect. However, in other embodiments of the present invention, the heat slug D may be formed of a single circuit layer as a heat slug D contacting with the surface of the electronic device C, and the number of circuit layers as the heat slug D is not limited in the embodiments of the present invention.

Please refer to fig. 2A, which is a cross-sectional view of a circuit board with a heat dissipation structure of an embedded device according to the present invention. The circuit board 1 with the embedded device heat dissipation structure comprises a circuit board circuit structure A1, a circuit board heat dissipation structure A2 and an electronic device C. The circuit board circuit structure a1 is disposed on the circuit board heat dissipation structure a2, and covers the electronic device C with the circuit board heat dissipation structure a 2. The circuit board heat dissipation structure a2 includes at least one opening H and at least one heat dissipation block D, the heat dissipation block D is disposed in the opening H and has a first surface D1 and a second surface D2, so that the electronic device C can conduct the generated heat energy from the first surface D1 to the second surface D2 through the heat dissipation block D and conduct the heat energy to the outside of the opening H, that is, to the outside of the circuit board 1 having the heat dissipation structure with embedded device, as indicated by the arrow mark direction.

The circuit board circuit structure a1 includes a first upper circuit layer 11a1, a first upper dielectric layer 12a1, a second upper circuit layer 13a1, a second upper dielectric layer 14a1, a third upper circuit layer 15a1, an upper insulating protective layer 16a1, an upper copper foil layer 102a1, and an upper adhesive layer 18a 1. The upper adhesive layer 18A1 is disposed in the upper copper foil layer 102A 1. The upper adhesive layer 18a1 and the upper copper foil layer 102a1 are disposed on the circuit board heat dissipation structure a 2. The electronic device C is disposed on the upper copper foil layer 102a1 and is in contact with the upper copper foil layer 102a 1. The first upper circuit layer 11a1 and the first upper dielectric layer 12a1 are disposed on the upper copper foil layer 102a1, and the first upper dielectric layer 12a1 covers the first upper circuit layer 11a1 and the electronic device C. The second upper dielectric layer 14a1 is disposed on the first upper dielectric layer 12a1 and covers the second upper circuit layer 13a 1. The third upper circuit layer 15a1 is disposed on the second upper dielectric layer 14a 1. The upper insulating passivation layer 16a1 is disposed on the second upper dielectric layer 14a1, covering a portion of the third upper circuit layer 15a1 and exposing a portion of the third upper circuit layer 15a 1.

The circuit board heat dissipation structure a2 further includes a first lower circuit layer 11a2, a first lower dielectric layer 12a2, a second lower circuit layer 13a2, a second lower dielectric layer 14a2, a third lower circuit layer 15a2, a lower insulating protection layer 16a2, a lower copper foil layer 102a2, and a lower adhesive layer 18a 2. The lower adhesive layer 18a2 is disposed in the lower copper foil layer 102a 2. The lower copper foil layer 102a2 is in contact with the upper copper foil layer 102a 1. The lower adhesive layer 18a2 and the lower copper foil layer 102a2 are disposed under the circuit board circuit structure a 1. The first lower circuit layer 11a2 and the first lower dielectric layer 12a2 are disposed under the lower copper foil layer 102a2, the first lower circuit layer 11a2 contacts the lower copper foil layer 102a2, and the first lower dielectric layer 12a2 covers the first lower circuit layer 11a 2. The second lower dielectric layer 14a2 is disposed under the first lower dielectric layer 12a2 and covers the second lower circuit layer 13a2, and the second lower circuit layer 13a2 contacts the first lower circuit layer 11a 2. The third lower circuit layer 15a2 is disposed under the second lower dielectric layer 14a2 and contacts the second lower circuit layer 13a 2. The lower insulating protective layer 16a2 is disposed under the second lower dielectric layer 14a2, covering a portion of the third lower circuit layer 15a2 and exposing a portion of the third lower circuit layer 15a2, wherein the lower insulating protective layer 16a2 is an opening H forming a heat dissipation structure a2 of the circuit board.

The heat slug D includes the first lower circuit layer 11a2, the second lower circuit layer 13a2 and the third lower circuit layer 15a2 in the circuit board heat dissipation structure a 2. The upper copper foil layer 102a1, the lower copper foil layer 102a2, the first lower circuit layer 11a2, the second lower circuit layer 13a2 and the third lower circuit layer 15a2 are stacked in sequence according to the above arrangement position relationship, so that the heat generated by the electronic device C is conducted to the outside of the opening H by the upper copper foil layer 102a1, the lower copper foil layer 102a2, the first lower circuit layer 11a2, the second lower circuit layer 13a2 and the third lower circuit layer 15a2, and conducted to the outside of the circuit board 1 having the heat dissipation structure of the embedded device, as shown by the arrow symbol direction. In addition, each circuit layer is made of a metal copper material having a high thermal conductivity, but in other embodiments of the present invention, other materials having a high thermal conductivity may be used to increase the thermal conductivity, which is not limited in the present invention. In addition, in the structure of fig. 2A, the heat dissipation block D is disposed in the opening H, but in order to enhance the heat dissipation effect, in other embodiments, the heat dissipation block D may also be disposed in a structure protruding out of the surface of the opening H.

As described above, since the heat conduction of the electronic device C is actually conducted to the outside of the opening H through the upper copper foil layer 102a1, the lower copper foil layer 102a2, the first lower circuit layer 11a2, the second lower circuit layer 13a2 and the third lower circuit layer 15a2, the heat dissipation block D broadly includes the lower copper foil layer 102a2 and even further includes the upper copper foil layer 102a 1.

The circuit board 1 with the heat dissipation structure of embedded device further includes a protrusion 19, wherein the protrusion 19 includes a portion of the upper copper foil layer 102a1 and a portion of the lower copper foil layer 102a2 protruding from the side surfaces of the heat dissipation structure a2 and the circuit structure a 1. Since the surface of the electronic device C is in direct contact with a portion of the upper copper foil layer 102a1 and is in indirect contact with a portion of the lower copper foil layer 102a2, the heat generated by the electronic device C can also be conducted to the outside of the circuit board 1 having the heat dissipation structure of the embedded device through the protrusion 19, as indicated by the horizontal arrow. In addition, in order to increase the heat dissipation effect, the areas of the first lower circuit layer 11a2, the second lower circuit layer 13a2, and the third lower circuit layer 15a2, which are in indirect contact with the surface of the electronic device C, are larger than the surface area of the electronic device C.

The upper adhesive layer 18a1 and the lower adhesive layer 18a2 are disposed around the first upper circuit layer 11a1 of the circuit board circuit structure a1 and the first lower circuit layer 11a2 of the circuit board heat dissipation structure a2, respectively, according to the requirement of whether the circuit layers need to be electrically connected, so that the first upper circuit layer 11a1 is electrically connected to the first lower circuit layer 11a 2. Alternatively, the upper adhesive layer 18a1 is adhered to the lower adhesive layer 18a2 to separate the first upper circuit layer 11a1 from the first lower circuit layer 11a 2. In the embodiment of the utility model, the upper adhesive layer 18a1 and the lower adhesive layer 18a2 are insulation glue (insulation glue).

Fig. 2B is a top view of the circuit board with the heat dissipation structure of the embedded device according to the present invention. As shown in fig. 2B, the circuit board 1 with the heat dissipation structure of embedded device according to the present invention can dissipate heat in various directions from the side of the circuit board 1 with the heat dissipation structure of embedded device, as indicated by arrows, in addition to conducting heat energy outward in the direction perpendicular to the surface of the heat dissipation block D.

In summary, the circuit board with the heat dissipation structure of the embedded device of the present invention conducts and dissipates the heat energy generated by the electronic device through the heat dissipation block with one surface contacting the electronic device and the other surface exposed in the opening, thereby further achieving the effect of rapid heat dissipation. Besides, the heat dissipation is achieved through the heat dissipation block, and the heat generated by the electronic device can be conducted and dissipated through the protruding portion protruding out of the side surface of the circuit board with the embedded device heat dissipation structure. Moreover, even if a plurality of electronic devices are required to be arranged at the same time, the effect of heat dissipation at the same time can be achieved through the arrangement of the circuit board with the embedded device heat dissipation structure.

Claims (9)

1. A circuit board with a heat dissipation structure of an embedded device, comprising:

the circuit board heat dissipation structure comprises at least one opening and at least one heat dissipation block, wherein the at least one heat dissipation block is arranged in the at least one opening and is provided with a first surface and a second surface;

at least one electronic device arranged on the at least one heat dissipation block and contacted with the first surface of the at least one heat dissipation block; and

a circuit board circuit structure arranged on the circuit board heat dissipation structure and covering the at least one electronic device;

the second surface of the at least one heat dissipation block is exposed in the at least one opening.

2. The circuit board with a heat dissipation structure of embedded devices as claimed in claim 1, wherein the heat dissipation structure of circuit board further comprises:

a lower copper foil layer arranged below the circuit board circuit structure and contacted with the circuit board circuit structure;

a lower dielectric layer disposed below the lower copper foil layer;

a lower circuit layer disposed in the lower dielectric layer; and

a lower insulating protective layer arranged below the lower dielectric layer, covering part of the lower circuit layer and exposing part of the lower circuit layer;

the at least one opening is disposed in the lower insulating protection layer, and the at least one heat dissipation block includes the lower circuit layer exposed in the opening.

3. The circuit board with a heat dissipation structure of embedded devices as claimed in claim 2, wherein the circuit board wiring structure comprises:

an upper copper foil layer arranged on the circuit board heat dissipation structure and contacted with the circuit board heat dissipation structure;

an upper dielectric layer disposed on the upper copper foil layer;

an upper circuit layer disposed in the upper dielectric layer and on the circuit board circuit structure, and contacting with part of the lower circuit layer; and

an upper insulating protective layer disposed on the upper dielectric layer, covering part of the upper circuit layer and exposing part of the upper circuit layer.

4. The circuit board of claim 3, further comprising a lower adhesive layer disposed in the lower copper foil layer.

5. The circuit board of claim 4, further comprising an upper adhesive layer disposed in the upper copper foil layer and contacting the lower adhesive layer.

6. The circuit board of claim 3, wherein a portion of the upper copper foil layer and the lower copper foil layer forms a protrusion protruding from a side surface of the heat dissipation structure of the circuit board.

7. The circuit board with a heat dissipating structure of embedded devices as claimed in claim 1, wherein the first surface area of the at least one heat slug is larger than a surface area of the at least one electronic device.

8. The circuit board of claim 3, wherein the at least one heat slug further comprises the lower copper foil layer.

9. The circuit board with a heat dissipation structure, as set forth in claim 8, wherein the at least one heat slug further comprises the upper copper foil layer.

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