TWI690246B - Built-in longitudinal heat dissipation ceramic block printed circuit board and circuit assembly with the circuit board - Google Patents

Abstract

A built-in longitudinal heat-dissipating ceramic block printed circuit board and a circuit component with the circuit board, wherein the circuit component includes: a piece of built-in longitudinal heat-dissipating ceramic block printed circuit board and a plurality of circuit components, the printed circuit board further includes: a dielectric At least one through hole; at least one heat dissipation ceramic block embedded in the through hole; at least one fixing portion for embedding the heat dissipation ceramic block in the through hole; one disposed on the dielectric material layer and The metal circuit layer on the upper plate surface of the heat-dissipating ceramic block and the high thermal conductivity layer provided on the lower plate surface. The invention can adjust the installation position and size of the heat dissipation ceramic block according to the needs, to achieve the purpose of complex circuit design, exert good heat conduction effect and control the heat conduction path, and reduce the manufacturing cost.

Description

Built-in longitudinal heat dissipation ceramic block printed circuit board and circuit assembly with the circuit board

A printed circuit board, in particular a printed circuit board with a built-in longitudinal heat dissipation ceramic block and a circuit assembly with the circuit board.

Printed Circuit Board (PCB) is a copper foil substrate as the main key base material for mounting electronic components. The copper foil substrate generally uses a dielectric material as an insulating layer and a conductor formed of copper foil It is a conductive material layer, and the conductive material layer is arranged on the dielectric insulating layer. Among them, dielectric materials are mainly made of paper, bakelite, glass fiber board, rubber and other types of polymers, which are impregnated with resin. For the convenience of subsequent description, the insulation layer of this copper foil substrate is called a dielectric material layer in this case.

With the increasingly complex and diverse requirements of circuit design, the structure of printed circuit boards has gradually evolved from single layer PCB to double layer PCB to multi layer PCB. At present, multilayer printed circuit boards use multiple dielectric material layers and conductive material layers to form a more complex and multi-element circuit, and by forming a through hole in the dielectric material layer, a plug is formed with a conductive material (Plug), and then connect the wires between the multi-layer boards to achieve the purpose of allowing more electronic components to be accommodated in a smaller occupied volume. Common FR-4, FR-5, FR-6, FR-7, etc. on the market are commonly used materials for multilayer PCBs.

As electronic devices continue to be miniaturized, electronic components with specific needs are developing toward higher power. As a result, higher heat generation is accompanied in a smaller space. especially The wire pitch of the wire and the wire diameter of the wire itself should be reduced. For example, on the substrate materials based on bakelite and glass fiber, the circuit spacing can be reduced to about 50 microns (μm), which makes the circuit field The problem of high temperature, which is difficult to handle due to the accumulation of heat energy, is becoming more serious.

High-power components consume large amounts of energy. On the one hand, they represent higher efficiency, but it is inevitable that a certain percentage of energy is converted into heat energy. Furthermore, electronic technology is developing towards the complexity and diversification of electronic circuit design and layout. When high-power electronic components begin to be installed on printed circuit boards, it means that more energy-consuming components will be designed in the same or even Working in a smaller space, under such a trend, the thermal energy problems will be more difficult to deal with than in the past. Since the insulating material of the copper foil substrate of the general printed circuit board is mostly a dielectric material, it is not a good conductor of heat, so that the heat energy generated by the high heating element is accumulated near the high power element, making the operating environment very undesirable. At the same time, excessive thermal accumulation usually also leads to the expansion of the printed circuit board, but the different thermal expansion coefficients between the printed circuit board and the circuit component also inevitably cause the risk of damage to the contacts due to thermal stress.

In order to improve the heat dissipation efficiency, there are currently the following methods: First, the heat energy generated by general electronic components diffuses to the air and environment around the printed circuit board through heat convection or heat radiation, but this heat dissipation efficiency is not high; The second is conduction through metal wires or heat sinks with better thermal conductivity. Although the heat dissipation effect of this type of structure is better than that of simple dielectric materials, the heat dissipation efficiency of this path is due to the small diameter of the metal wires. It is not high; and the heat sink usually needs to be fixed to the printed circuit board through a material such as thermal paste, but the thermal conductivity of the thermal paste itself is much lower than that of metal, so even if a fan is installed at the far end of the heat sink away from the heat-generating electronic component, the heat The thermal conductivity of the film will also be greatly reduced.

Another solution is to install a heat pipe, but the heat pipe not only takes up space, structure It is also relatively complicated and the manufacturing cost has increased greatly. Other solutions include changing the material or structure of the printed circuit board, such as a metal core printed circuit board (Metal Core) with aluminum (thermal conductivity 237Wm-1K-1) as the metal core PCB, MCPCB), but due to technical factors, there is currently no multi-layer board structure, unable to respond to complex circuit design; and layout distortion is easy to occur in the process of processing, so it cannot be widely adopted.

At present, the most commonly adopted solution is to use ceramic materials as the insulating material layer of the circuit substrate. The most common ceramic materials are direct bonded copper (DBC) substrates made of aluminum oxide (Aluminium Oxide, Al2O3). Among them, the thermal conductivity of aluminum oxide can reach 35Wm ^-1 K ^-1 in the single crystal structure, and 20 to 27Wm ^-1 K ^{-1 in the} polycrystalline structure. Other common ceramic substrates include aluminum nitride (AlN), beryllium oxide (BeO), and silicon carbide (SiC). Since the ceramic material with good thermal conductivity is commonly used in circuit boards with high-power electronic components, such substrates are sometimes called high-power printed circuit boards (Power Electronic Substrate).

However, in practice, if a printed circuit board made of a ceramic material substrate is to be used, although the wire diameter of the circuit can be as thin as 30 microns (μm), since high temperature firing is usually used, on the one hand, a small amount of Uneven expansion and warpage, so the precision of the substrate is not as good as that of printed circuit boards and is not suitable for the manufacture of multilayer boards; on the other hand, it is easy to freely diffuse the metal atoms constituting the circuit during high-temperature processes, so that the wire spacing must be maintained at about 80 microns (μm) . Therefore, in addition to increasing the cost of manufacturing a printed circuit board using a ceramic material substrate, the width and spacing of the wires cannot be reduced, and the accuracy of the position of the wire circuit makes the volume of the electronic device using the entire ceramic material substrate cannot be miniaturized.

Therefore, for electronic components with high heat generation, electronic components are often installed first After being packaged, it is placed on a resin printed circuit board to form a stacked bed structure, which not only increases the volume of the printed circuit board, but also requires a poor thermal conductivity between the ceramic block and the thermally conductive element. Material conduction will reduce the original heat dissipation efficiency.

For example, some manufacturers propose to use a semiconductor process to deposit heat dissipation materials on the etched dielectric substrate to make a composite heat dissipation substrate as shown in FIG. 1; however, since the semiconductor process equipment is quite expensive, this manufacturing method The cost is rising, especially considering the cost sharing of the photomask in the manufacturing process, so it is not suitable for a small number of diverse products, and it is quite limited in the manufacturing process, and it is not generally used by general substrate factories.

Therefore, on the one hand, how can it be combined with a finer wire diameter and a smaller wire spacing to make the circuit design more miniaturized and occupy less space; and provide better thermal conductivity, making the application of high-power electronic components feasible At the same time, it can also manufacture a small amount of diverse products according to the needs of different customers and provide manufacturing flexibility, which is the purpose of this case.

An object of the present invention is to provide a built-in longitudinal heat dissipation ceramic block printed circuit board with good heat conduction efficiency at high-power components, and can provide an elastic circuit design in the remaining part.

Another object of the present invention is to provide a printed circuit board with a built-in longitudinal heat dissipation ceramic block which can be provided with a heat dissipation position as required, making a small variety of circuit layouts feasible.

Another object of the present invention is to provide a printed circuit board with a built-in longitudinal heat dissipation ceramic block that can more effectively design a heat conduction path through the heat dissipation ceramic block that penetrates up and down.

Another object of the present invention is to provide a space-saving built-in longitudinal heat dissipation ceramic Porcelain block printed circuit board; the heat dissipation ceramic block is embedded in the through hole on the printed circuit board, so that the lower plate surface without components can be thermally connected to the heat dissipation device, and the overall heat dissipation effect is improved.

Yet another object of the present invention is to provide a printed circuit board with a built-in longitudinal heat dissipation ceramic block that is more economical than a ceramic material substrate.

Still another object of the present invention is to provide a printed circuit board with a built-in longitudinal heat-dissipating ceramic block. By synchronously forming a metal circuit layer on the upper plate surface of the heat-dissipating ceramic block and the dielectric material layer of the printed circuit board, the The integrated printed circuit board makes the overall structure simple and the manufacturing cost low.

Therefore, the present invention discloses a printed circuit board with a built-in longitudinal heat dissipation ceramic block, including: a dielectric material layer, including a first upper plate surface and a first lower plate surface opposite to the first upper plate surface, and, the The dielectric material layer is formed with at least one through hole penetrating the first upper plate surface and the first lower plate surface; at least one heat dissipation ceramic block correspondingly embedded in the through hole includes a second upper plate surface and a second Lower plate surface, the thermal conductivity of the heat dissipation ceramic block is higher than that of the dielectric material layer; at least one fixing portion that embeds the heat dissipation ceramic block in the through hole of the dielectric material layer and makes the second upper plate surface respectively Corresponding to the first upper plate surface, and the second lower plate surface respectively correspond to the first lower plate surface; a metal circuit layer disposed on the first upper plate surface and the second upper plate surface; and a A high thermal conductivity layer disposed below the first lower plate surface and the second lower plate surface, wherein the thermal conductivity of the high thermal conductivity layer is higher than the heat dissipation ceramic block.

When a plurality of circuit components including high-power components are mounted on the above-mentioned built-in longitudinal heat-dissipating ceramic block printed circuit board, a circuit assembly of the present invention can be constituted, including: a piece of built-in longitudinal heat-dissipating ceramic block printed circuit board, including : A dielectric material layer, including a first upper plate surface and a first lower plate surface opposite to the first upper plate surface, and the dielectric material layer is shaped There is at least one through hole penetrating the first upper plate surface and the first lower plate surface; at least one corresponding heat dissipation ceramic block embedded in the through hole includes a second upper plate surface and a second lower plate surface, The thermal conductivity of the heat dissipation ceramic block is higher than that of the dielectric material layer; at least one fixing portion that embeds the heat dissipation ceramic block in the through hole fixed to the dielectric material layer, and makes the second upper plate surfaces correspond to the first The upper board surface and the second lower board surface respectively correspond to the first lower board surface; a metal circuit layer disposed on the first upper board surface and the second upper board surface for providing a plurality of circuit elements, wherein The circuit element includes at least one high-power element, and the high-power element is provided at the metal circuit layer disposed on the second upper board surface; and one disposed on the first lower board surface and the second lower board surface A high thermal conductivity layer below, wherein the thermal conductivity of the high thermal conductivity layer is higher than the above-mentioned heat-dissipating ceramic block; and a plurality of circuit components, including at least one high-power component, and the foregoing high-power component is provided on the second upper plate surface At the metal circuit layer.

The present invention reduces the area of expensive ceramic materials by relatively simple manufacturing procedures and thus reduces manufacturing costs, and combines the good thermal conductivity of ceramic materials and the advantages of printed circuit boards that can allow complex circuit designs, not only in line with the trend of circuit miniaturization, and Provides good heat conduction for high-power circuit components, thereby ensuring the appropriate temperature of the operating environment; furthermore, the present invention can effectively control the thermal energy conduction path to ensure the good operation of other electronic components, in particular, meet a small number of diverse manufacturing needs, thereby increasing printing The flexibility of the circuit board.

1‧‧‧Built-in longitudinal heat dissipation ceramic block printed circuit board

2. 2’‧‧‧ circuit components

11, 11’‧‧‧ dielectric material layer

111, 111’‧‧‧ first board surface

113、113’‧‧‧First lower plate

115‧‧‧Through hole

117, 117’‧‧‧ perforated inner edge

13, 13’‧‧‧Ceramic block

131,131’‧‧‧Second upper surface

133、133’‧‧‧Second lower plate

135, 135’‧‧‧ outer periphery

15, 15’‧‧‧ fixed part

17, 17’‧‧‧ metal circuit layer

19.19’‧‧‧High thermal conductivity layer

8’‧‧‧ Fin

9, 9’‧‧‧ High power components

FIG. 1 is a schematic side view of a prior art illustrating the structure of a circuit assembly and a printed circuit board.

2 is a printed circuit board with a built-in longitudinal heat dissipation ceramic block and a circuit group with the circuit board of the present invention The schematic side view of the first preferred embodiment of the device illustrates the relative position of the heat-dissipating ceramic block in the printed circuit board and the overall structure of the circuit assembly.

FIG. 3 is a partial perspective perspective view of FIG. 2 for explaining the internal structure and combination of printed circuit boards.

4 is a three-dimensional exploded view of FIG. 2.

FIG. 5 is a schematic side view of the circuit assembly of the present invention, used to explain the state of the present invention carrying an IGBT (Insulated Gate Bipolar Transistor).

6 is a schematic side view of a second preferred embodiment of a printed circuit board with a built-in longitudinal heat-dissipating ceramic block and a circuit component with the circuit board according to the present invention, for explaining the state of the present invention carrying LEDs.

The foregoing and other technical contents, features and effects of the present invention will be clearly presented in the following detailed description of the preferred embodiments with reference to the drawings; in addition, in each embodiment, the same elements will be similar The label indicates.

The first preferred embodiment of a printed circuit board with a built-in longitudinal heat-dissipating ceramic block and a circuit component with the printed circuit board of the present invention, as shown in FIGS. 2 to 5, is a FR-4 with a length and width of 10 cm each Based on the multi-layer dielectric material layer 11, a through hole 115 with a length and width of 2 cm is pre-cut into the dielectric material layer 11 by a laser, for example, and the corresponding square material such as aluminum oxide (Al ₂ O ₃ ) is square The columnar heat-dissipating ceramic block 13 is embedded in the through hole 115. However, as those skilled in the art can easily understand, the size of the FR-4 substrate in this embodiment can be simply replaced within a range from more than 10 cm ² to less than 3600 cm ² .

For ease of explanation, the surface of the dielectric material layer 11 above the drawing is referred to as the first upper plate surface 111, and the opposite lower surface is referred to as the first lower plate surface 113 according to the direction of the drawing. The upper and lower surfaces of the block 13 are respectively referred to as a second upper plate surface 131 and a second lower plate surface 133, and the thickness of the dielectric material layer 11 and the thickness of the heat dissipation ceramic block 13 are similar. Of course, those skilled in the art can easily understand whether the above-mentioned dielectric material layer 11 is changed to epoxy resin or glass fiber prepreg such as FR-1 (commonly known as bakelite), FR-3, FR-6, G-10, etc. Yes; the cutting method can also be mechanical cutting, etc., the heat-dissipating ceramic block 13 can choose silicon nitride (Si ₃ N ₄ ), aluminum oxide (Al ₂ O ₃ ), silicon carbide (SiC), beryllium oxide (BeO) Such substitutions will not hinder the implementation of this case.

Then fill the gap between the outer periphery 135 of the aluminum nitride heat-dissipating ceramic block 13 and the perforated inner edge 117 of the FR-4 dielectric material layer 11 with epoxy resin glue. After the glue is cured, the heat-dissipating ceramic The outer edge 135 of the block is firmly combined with the inner edge 117 of the perforation, and the fixed portion 15 formed by the curing of the adhesive material also has greater flexibility than the heat dissipation ceramic block 13, so it is a mechanical buffer mixed material, making the two different materials Coefficients of thermal expansion vary, and still provide cushioning protection. Of course, those skilled in the art can easily deduce that although epoxy resin is used as an example in this example, the use of silicon as the base or other flexible adhesive materials is a simple change, which does not hinder the implementation of this case.

After the heat dissipation ceramic block 13 is embedded in the through hole 115 of the dielectric material layer 11 by the fixing portion 15, it may be polished to make the first upper plate surface 111 and the second upper plate surface 131 flush with each other, so as to facilitate further In this example, a metal seed layer of titanium and a layer of copper is sequentially formed on the first and second upper plate surfaces by sputtering, for example, and then the metal seed layer is thickened by electroplating to form a The copper layer is electroplated, and in order to protect the copper layer from being easily oxidized, in this example, a layer of nickel and gold is added above the copper layer to form a metal layer of the multilayer structure. Of course, those skilled in the art can easily understand that the above-mentioned protective copper layer materials, regardless of the substitution of Organic Solderability Preservatives (OSP), silver, tin and other materials, will not hinder the implementation of this case. The aforementioned metal layer undergoes a series of subsequent conventional processing procedures such as pattern, which is the gold in this example Owned circuit layer 17. Of course, those skilled in the art can also use, for example, common evaporation or other feasible methods, and use other suitable metals to form the metal circuit layer of the above-mentioned multilayer structure.

Since the first lower plate surface 113 and the second lower plate surface 133 are also flush with each other, and copper has a better thermal conductivity (380 Wm ^-1 K ^-1 ), in this example, the first lower plate surface 113 and A metal layer of copper is also formed under the second lower plate surface 133, thereby forming a high thermal conductivity layer 19 having a thermal conductivity higher than that of the aforementioned dielectric material layer 11. Since the high thermal conductivity layer 19 simultaneously connects the dielectric material layer 11 and the heat dissipation ceramic block 13 with good thermal contact, the thermal conductivity of the heat dissipation ceramic block 13 and the high thermal conductivity layer 19 is much higher than that of the dielectric material layer 11, so the high thermal conductivity layer 19 is mainly to re-export the heat energy transferred from the heat-dissipating ceramic block 13 from the horizontal direction of the figure. In contrast, the general circuit components (not shown) provided above the dielectric material layer 11 will not be easily affected by the heat-dissipating ceramic block The heat energy transmitted by 13 interferes, thereby isolating the high heat emitted by the high-power element 9 from other peripheral circuit elements.

After the above dielectric material layer 11 is completed, it can be used to further install the required circuit components. The foregoing circuit components further include at least one high-power component 9. In this example, the high-power component 9 is interpreted as an IGBT. For example, a surface-mount technology (SMT) is soldered and fixed to the pad above the heat dissipation ceramic block 13, and each electrode of the IGBT is connected to the corresponding pad through a metal lead. Because IGBT has the advantages of high efficiency and fast switching speed, it is often used in electronic equipment with a large amount of work, such as air conditioners, refrigerators, audio, and motor drivers. Therefore, when the aforementioned electronic equipment operates, IGBT will generate a lot of The thermal energy will directly pass through the heat-dissipating ceramic block 13 of aluminum oxide (Al2O3) and be conducted down to the high thermal conductivity layer 19, while being conducted away from the position of the thermal ceramic block 13, the aforementioned thermal energy will further pass through the high thermal conductivity layer 19 For large-area heat dissipation, even an active fan and/or water cooling system (not shown) can be installed at the far end to achieve the effect of increasing heat dissipation efficiency.

Of course, those skilled in the art can also easily replace the heat dissipation fins (not shown) directly attached to the aforementioned high thermal conductivity layer 19, and in the transfer process, since they are not high-power circuit components, they are mainly installed The position of the metal circuit layer 17 corresponding to the surrounding printed circuit board is protected by the relatively low thermal conductivity of the printed circuit board, and the heat energy emitted by the high-power element 9 will not easily affect the surrounding circuit elements. That is, the heat dissipation ceramic block 13 can transfer thermal energy at a high speed in the longitudinal direction, but it does not transfer a large amount of unnecessary thermal energy to the dielectric material layer 11 to interfere with its operation. Therefore, after the high-power component 9 is mounted on the built-in longitudinal heat-dissipating ceramic block printed circuit board 1 of the present invention, the circuit component 2 formed together can achieve the so-called thermoelectric separation effect, and all components that do not emit high heat are kept in A better low-temperature working environment, and retain the complexity and miniaturization advantages of printed circuit boards.

A second preferred embodiment of a printed circuit board with a built-in longitudinal heat-dissipating ceramic block and a circuit component with the circuit board of the present invention is shown in FIG. 6 as an example of a circuit component 2'with high-power components. The component 2'is installed on a street lamp as an illumination light source, wherein the high-power element 9'in the circuit component 2'is more exemplified as a high-power LED, and the same parts as the first preferred embodiment in this example are here Omit not to repeat. In this example, the dielectric material layer 11 ′ is a flexible substrate with a size of approximately 100 cm ² , and the size of the heat dissipation ceramic block 13 ′ is between 0.01 cm ² and 25 cm ² . However, as those skilled in the art can easily understand, the flexible substrate in this embodiment can be easily replaced in the range of 5 cm ² to 3600 cm ² under the limitation of larger than the heat dissipation ceramic block.

In this example, the heat dissipation ceramic block 13' is made of aluminum nitride (AlN). When the heat dissipation ceramic block 13' is embedded in a flexible substrate, a plurality of high-power LEDs are installed at the plurality of heat dissipation ceramic blocks 13', respectively. The driving circuit is disposed on the first upper plate surface 111' of the dielectric material layer 11'. The printed circuit board has a flexible base material, which can be installed in accordance with the current environment and is rich in elasticity. In contrast, the heat-dissipating ceramic block 13' may also be provided in accordance with the shape of the flexible dielectric material layer 11'. In this example, the outer peripheral edge 135' that is not perpendicular to the second upper plate surface 131' and the second lower plate surface 133' and has a lower width and a narrower width is not the smallest connecting surface, which corresponds to non-perpendicular to the first upper plate surface 111 The non-minimum connection surface of the perforated inner edge 117' of the through hole (not shown) of the first lower plate surface 113' achieves the effect of assisting the embedding.

The fixing portion 15' between the dielectric material layer 11' and the heat-dissipating ceramic block 13' in this example is a thermally conductive silicone rubber, and other materials such as graphite, phase change materials, etc., have a higher thermal conductivity than the dielectric material layer 11'. Rubber materials can be easily replaced by those skilled in the art. The heat-conducting silicone rubber of the fixing portion 15' has the effect of assisting heat transfer. In this example, the heat-conducting silicone rubber is used to attach a heat-dissipating fin 8'to the high heat-conducting layer 19' as a heat-dissipating device. Of course, the high thermal conductivity layer 19' can also add additional aids such as screw locks to strengthen the combination with the dielectric material layer 11' and the heat dissipation ceramic block 13', making the bonding surface less likely to produce air gaps. Furthermore, at the high thermal conductivity layer 19', for example, a heat pipe or graphene products can be further provided to increase the heat dissipation effect.

Due to the circuit assembly 2'of the present invention, the heat dissipating ceramic blocks 13' flush with the top and bottom are longitudinally embedded in the dielectric material layer 11', and a metal circuit layer 17' and a high thermal conductivity layer 19 are formed on the top and bottom plates respectively 'Because the thermal conductivity of the high thermal conductivity layer 19' is higher than that of the above-mentioned heat-dissipating ceramic block 13', the heat generated by the high-power element 9'placed at the heat-dissipating ceramic block 13' is mainly passed through the heat-dissipating ceramic block 13' The other circuit components (not shown) carried by the high thermal conductivity layer 19' and relatively disposed at the dielectric material layer 11' are less susceptible to interference from the heat generated by the high power component 9', thereby achieving the effect of thermoelectric separation . And because there is no need to use a higher-priced whole ceramic material substrate, it is more economical in terms of material cost; the combination of the two is simple, making manufacturing convenient, and can be produced by a small number of diverse production and use flexibility; of course, here The heat-dissipating ceramic block is not limited to columnar or square, Even if the cross-sectional area of the heat-dissipating ceramic block is U-shaped or other shapes, it is a simple change, which does not hinder the implementation of this case. At the same time, when it is matched with but not limited to a mature resin printed circuit board, the overall circuit design can not only be multi-layered In order to meet the requirements of complexity and miniaturization, and it does not require the use of semiconductor machines at all, which greatly reduces the cost of the product and effectively achieves the above purpose of the invention.

However, the above are only the preferred embodiments of the present invention, and cannot limit the scope of the implementation of the present invention. Any simple equivalent changes and modifications made according to the scope of the patent application of the present invention and the content of the description of the invention should be It still falls within the scope of the invention patent.

1‧‧‧Built-in longitudinal heat dissipation ceramic block printed circuit board

11‧‧‧Dielectric material layer

13‧‧‧Ceramic block

15‧‧‧Fixed Department

17‧‧‧Metal circuit layer

19‧‧‧High thermal conductivity layer

2‧‧‧circuit assembly

9‧‧‧High power components

Claims (1)

A built-in longitudinal heat dissipation ceramic block printed circuit board, comprising: a dielectric material layer, including a first upper board surface and a first lower board surface opposite to the first upper board surface, and the dielectric material layer At least one through hole penetrating through the first upper plate surface and the first lower plate surface; at least one heat dissipation ceramic block correspondingly embedded in the through hole, including a second upper plate surface and a second lower plate surface, The thermal conductivity of the heat dissipation ceramic block is higher than that of the dielectric material layer; at least one fixing portion that embeds the heat dissipation ceramic block in the through hole fixed to the dielectric material layer, and makes the second upper plate surfaces correspond to the first An upper board surface and the second lower board surface respectively correspond to the first lower board surface; a metal circuit layer disposed on the first upper board surface and the second upper board surface for providing a plurality of circuit elements, Wherein the circuit element includes at least one high-power element, and the high-power element is provided at the metal circuit layer disposed on the second upper board surface; and one disposed on the first lower board surface and the second lower board A high thermal conductivity layer below the surface, wherein the thermal conductivity of the high thermal conductivity layer is higher than the heat dissipation ceramic block; wherein the area of the dielectric material layer is between 5cm ² and 3600cm ² and the area of the heat dissipation ceramic block is between 0.01 and 25cm ² .

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