TW202137422A - High-thermal-conductivity ceramic substrate with protective connecting pad and high-power module including the substrate connecting the high-thermal-conductivity ceramic substrate to a metal heat radiator in a heat conducting manner - Google Patents

Abstract

A high-thermal-conductivity ceramic substrate with a protective connecting pad is provided for receiving at least one high-power circuit component welded and mounted thereto. The high-thermal-conductivity ceramic substrate is connected to a metal heat radiator in a heat conducting manner. The high-thermal-conductivity ceramic substrate includes a substrate body having a setting surface and a mounting and heat radiating surface opposite to the setting surface in a height direction; at least one circuit layer disposed on the setting surface of the substrate body, wherein the circuit layer includes at least one metal fusion-welding pad for ultraviolet welding and at least one mounting pad for welding the high-power circuit component; and a plurality of metal heat radiating and mounting blocks formed on the mounting and heat radiating surface of the substrate body and spaced from each other and connected with the metal heat radiator in a heat conducting manner, wherein each of the metal heat radiating and mounting blocks includes at least one supportive and protective connecting pad which fully covers the fusion-welding pads on a projection surface vertical to the height direction and stably vibrates.

Description

High thermal conductivity ceramic substrate with protective pad and high-power module with the substrate

A high thermal conductivity ceramic substrate, in particular a high thermal conductivity ceramic substrate with a protective pad with a special structure design.

With the promotion of environmental protection awareness, the issue of air pollution has been widely reported by the media, making more and more consumers choose electric vehicles instead of traditional vehicles powered by internal combustion engines, such as electric vehicles instead of two-stroke locomotives and electric motorhomes instead of traditional cars , And these electric vehicles rely on high-power electric motors to provide power. Therefore, the market has a very strong demand for high-power power control components, which has also caused major suppliers to rush to invest in research and development, such as Renesas Electronics (Renesas Electronics). ) Announced the launch of 100 ampere high-current power metal oxide semiconductor field effect transistors (MOSFETs), suitable for motor drives in consumer products, such as wireless power tools and power assisted bicycles.

The large amount of energy consumed by the above-mentioned high-power components represents higher current efficiency. However, the high-power components themselves have internal resistances and large operating currents. Therefore, it is inevitable that a certain proportion of electrical energy will be converted into thermal energy. If the heat energy of the high-power components cannot be dissipated as quickly as possible, the heat generated by the high-heating components will accumulate in the vicinity of the high-power components, making the operating environment of the high-heating components very unsatisfactory and affecting their working performance. At present, the more commonly adopted solution is to use ceramic materials as the insulating material layer of the circuit board, and the ceramic substrate as the circuit board One type, which has a thermal expansion coefficient close to that of semiconductors and high heat resistance, especially compared to traditional circuit substrates such as FR4, has good thermal conductivity, is suitable for products with high calorific value, and has high hardness and good processability , High dimensional accuracy, high insulation resistance, and strong circuit pattern adhesion, coupled with abundant sources of materials and easy to obtain, it has become the first choice for printed circuit substrates used to configure high-power components.

The most common ceramic materials are Direct Bonded Copper (DBC) substrates made of aluminum oxide (Al2O3). Among them, the thermal conductivity of aluminum oxide can reach 35Wm ^-1 K ^{-1 under a single crystal structure.} There are 20 to 27 Wm ^-1 K ^-1 under the crystal structure. Other common ceramic substrates include aluminum nitride (AlN), beryllium oxide (BeO), and silicon carbide (SiC). Since the above-mentioned ceramic materials with good thermal conductivity are commonly used in circuit substrates with high-power electronic components, this type of substrate is sometimes referred to as a high-power printed circuit substrate (Power Electronic Substrate).

Aluminum conductive strips will quickly react with oxygen in the air to form an oxide film, which can prevent further oxidation. Therefore, aluminum conductive strips are commonly used wire bonding materials for high-power component brush-drawing circuits. However, because of the strong oxidation activity of aluminum, an oxide layer is quickly formed on the surface during high temperature welding and cannot be connected to the solder. Therefore, the traditional thermoelectric welding method cannot weld the aluminum conductive strip to the copper welding pad, as shown in Figure 1. As shown, generally, the aluminum conductive strip 85 and the welding pad 86 are welded by using, for example, an ultrasonic vibration welding device 84. However, compared with the traditional FR-4 plastic substrate, the ceramic substrate body 87 is hard and brittle, and it is very easy to break during ultrasonic vibration and cause circuit disconnection. Therefore, the manufacturing rate has been difficult to increase, which directly reduces the production capacity and improves cost.

In addition, although high-power components can be easily soldered on the pads laid out on the surface of the ceramic substrate by soldering, they are prone to excessive heat accumulation due to the printed circuit board and The thermal expansion coefficients of circuit components are different. The thermal expansion coefficients of metal copper and aluminum are 16.5 and 23 ppm/K, while the ceramic materials alumina, aluminum nitride and silicon nitride are about 7, 4.5 and 3.5 ppm/K, respectively. When the thermal expansion coefficient difference between the substrate and the bonded metal layer is too large, the thermally conductive pad 90 will expand more than the substrate body 87 due to repeated thermal expansion and contraction in a high-temperature welding environment or operating environment, resulting in a thermally conductive pad 90 The copper layer will warp and deform. The interface between the metal and the ceramic substrate is prone to cracking, warping or deformation and peeling. It will also inevitably cause the risk of damage to the contacts due to thermal stress. Generally, efficient heat dissipation means are required. In order to effectively solve the problem of thermal energy accumulation.

To this end, currently commonly used methods are as follows: One is to configure a large range of vacant spaces between high-power circuit components and other circuit components, and dissipate the emitted heat energy to the periphery of the printed circuit board through thermal convection or thermal radiation. The heat dissipation efficiency is not high in the air and environment. Second, in the high-power component 88 as shown in FIG. , And then through the thermally conductive adhesive 91 and other materials to thermally connect the metal heat sink 92 (Heat-Sink) with better thermal conductivity to conduct and dissipate the thermal energy emitted by the high-power circuit element 89, but because the thermal expansion coefficient of copper is much greater than that of the ceramic substrate, this This method will cause the substrate body 87 to warp, deform or even break, and the thermal conductive pad 90 will also warp, deform or even peel off, resulting in low heat dissipation efficiency, and the thermal conductivity of the thermal conductive glue 91 itself is much lower than that of metal, so even in the metal heat sink 92 If a fan is installed at the far end away from the heat-generating electronic components, the heat conduction effect of the metal heat spreader will be greatly reduced.

In addition, generally on the back of a thermally conductive circuit board with high-power components soldered, a layer of copper, such as a copper layer, is often grown on the back as a thermally conductive pad 90 through methods such as sputtering, so as to be similar to a metal heat sink made of copper, for example. 92 is properly combined, and the thermal energy emitted by the high-power circuit element 89 is conducted and dissipated. Therefore, the general plan is to form the front surface of the ceramic substrate body 87, which contains The mounting pad 93 for welding the high-power circuit element 89 and the welding pad 86 for welding the aluminum conductive strip 85 are used to form a high-thermal-conductivity ceramic substrate 98 so that the heat of the high-power element can be derived from the metal heat sink 92.

Please refer to Figure 2. In order to overcome this problem, the applicant further divides the entire copper layer into multiple pieces of smaller area and a slight gap 94, such as hexagonal copper layer blocks 95. On the one hand, it can still be The upper ceramic substrate and the lower fin-shaped metal heat sink maintain good bonding and thermal contact. On the other hand, when the copper layer block 95 expands and shrinks, the slight gap 94 can be used as a bridge or rail expansion joint. The buffer zone prevents the thermal expansion difference between the copper layer block 95 and the ceramic from causing structural damage such as peeling of the warped area.

However, when the respective sizes of the copper layer blocks 95 are too small, because the ultrasonic oscillation welding equipment 84 performs ultrasonic oscillation welding, the substrate body 87 corresponding to the above-mentioned slight gap 94 will lack support under the copper layer blocks 95, and thus It is very easy to produce slight cracking slits under the synergistic effect of ultrasonic oscillation and temperature rise, and even cause the problem of circuit disconnection. Therefore, the yield rate of manufacturing has been difficult to increase, which directly limits the production capacity and keeps the cost high. The gap 94 under the high-power circuit element 89 also lacks the direct heat dissipation of the copper layer block 95, so that the heat generated by the high-power circuit element 89 accumulates around the gap 94 and cannot be fully dissipated.

Especially as shown in Figure 3, the applicant is better at pre-forming an opening 97 slightly larger than the size of the ceramic substrate in a multilayer printed circuit board 96 such as FR-4, and then solidify and adhere the high thermal conductivity ceramic substrate 98 with an insulating glue 99 In the opening 97, the remaining low-current circuits and related components used to drive or control the high-power circuit components 89 are arranged on the FR4 circuit board in a high-density and high-complexity structure, and are connected to the circuit on the ceramic substrate. Connect each other to form a special composite circuit board.

The circuit board of this structure is called a thermoelectric separation circuit board, on the one hand, it can be large The large amount of heat energy emitted by the power circuit element 89 is first carried out longitudinally through the substrate body 87 and the metal heat sink below the figure to prevent other circuit elements in the FR-4 copper foil printed circuit board 96 from being emitted by the high-power circuit element 89. The influence of thermal energy; on the other hand, complex circuit design does not need to accommodate the simple structure of the ceramic substrate. It can be fully utilized in the multilayer board, miniaturized as much as possible, and relatively expensive ceramic substrate materials are saved.

Therefore, how to protect the hard and brittle ceramic substrate body from cracking during ultrasonic welding, improve the warpage deformation of the thermal conductive pad and the ceramic substrate, and at the same time ensure a good thermal connection between the metal heat sink and the thermal conductive pad, is this case The purpose to be achieved.

An object of the present invention is to provide a high thermal conductivity ceramic substrate with protective pads, which can greatly reduce the risk of cracking of the ceramic substrate when welding aluminum conductive strips by ultrasonic oscillation, and effectively improve the product yield.

Another object of the present invention is to provide a highly thermally conductive ceramic substrate with protective pads for sufficient heat dissipation when high-power circuit components are in operation, so as to avoid warping, deformation or cracking of the uniform thermally conductive pads on the back of the ceramic substrate.

Another object of the present invention is to provide a high-power module with a high thermal conductivity ceramic substrate with protective pads, which can improve the thermal conductivity between the uniform thermal pads and the metal heat sink fins, so that the high-power components can emit heat faster Dissipate without accumulating to improve its work efficiency.

To achieve the above objective, the present invention discloses a high thermal conductivity ceramic substrate with protective pads for soldering to set at least one high-power circuit element with a working current of tens of amperes, and the high thermal conductivity ceramic substrate is thermally connected to a metal heat sink. The high thermal conductivity ceramic substrate includes: a substrate body with a mounting surface and a mounting surface opposite to the mounting surface in a height direction Hot surface; at least one circuit layer arranged on the above-mentioned setting surface of the substrate body, the aforementioned circuit layer includes at least one metal material for ultrasonic welding welding pad, and at least one mounting pad for welding the above-mentioned high-power circuit components; and plural shapes Metal heat-dissipating mounting blocks arranged on the mounting and heat-dissipating surfaces of the substrate body and spaced apart from each other for thermally connecting to the metal heat sink; wherein the metal heat-dissipating mounting blocks corresponding to the welding pad in the height direction are at least one vertical The projection surface in the height direction is fully covered with the oscillation stable support and protection pad of the welding pad. And at least one uniform heat conducting pad that fully covers the mounting pad on the projection surface perpendicular to the height direction.

When a metal heat sink is installed on a high thermal conductivity ceramic substrate with protective pads, a high-power module of the present invention can be constructed, which includes: at least one high-power circuit element with a working current of several tens of amperes; A metal heat sink; a high thermal conductivity ceramic substrate for soldering the high-power circuit components and thermally connecting the metal heat sink, the high thermal conductivity ceramic substrate includes: a substrate body with a setting surface and a height direction opposite to the The mounting surface of the mounting surface; at least one circuit layer arranged on the mounting surface of the substrate body, the aforementioned circuit layer includes at least one metal welding pad for ultrasonic welding, and at least one mounting pad for welding the above-mentioned high-power circuit components And a plurality of metal heat dissipation mounting blocks formed on the mounting heat dissipation surface of the substrate body and spaced apart from each other for thermally conductive connection to the metal heat sink; wherein, the metal heat dissipation mounting blocks corresponding to the welding pad in the height direction are At least one support and protection pad that fully covers the welding pad on the projection surface perpendicular to the height direction and is stable in oscillation. And at least one uniform heat conducting pad that fully covers the mounting pad on the projection surface perpendicular to the height direction.

In the present invention, the mounting and heat dissipation surfaces of the substrate body of the ceramic substrate are arranged to be spaced apart from each other The metal heat-dissipating mounting block includes: by covering the welding pad on the projection surface perpendicular to the height direction, the oscillation stable support and protection pad is used to prevent the ceramic substrate from breaking and circuit damage during ultrasonic oscillation welding ; And by the uniform thermal pads corresponding to the mounting pads in the above height direction, to prevent the ceramic substrate and uniform thermal pads from warping and deforming or even breaking, moreover, by covering the uniform thermal pads below, high power The heat generated by the circuit components can be smoothly and effectively discharged to the radiator under the ceramic substrate, thereby ensuring the proper temperature of the operating environment, and effectively ensuring the working efficiency and service life.

1, 1’, 98: High thermal conductivity ceramic substrate

10, 10’, 87: Substrate body

102: Set the surface

104: Install the cooling surface

12: Circuit layer

122, 122’, 86: Welding pad

124, 124’, 93: Mounting pad

14, 14’: Metal heat-dissipating mounting block

140, 140’, 140”, 140''': Support and protection pads

142, 142’, 142”, 142''': uniform thermal pad

144’: Other metal heat dissipation installation blocks

146": Stepped structure

16, 16’, 94: gap

17, 84: Ultrasonic vibration welding equipment

2, 2’, 89: High-power circuit components

3.92: Metal radiator

5. 5’, 85: Aluminum conductive strip

7’: Copper conductive strip

8’, 96: printed circuit board

81’, 97: opening

82’, 99: insulating rubber material

83’: Welding pad

88: High-power components

9: High-power module

90: Thermally conductive pad

91: Thermal conductive glue

95: Copper layer block

FIG. 1 is a schematic side view of a prior art high-power module.

Fig. 2 is a schematic side view of ultrasonic welding of a prior art high-power module.

FIG. 3 is a schematic top view of a prior art high thermal conductivity ceramic substrate.

4 is a schematic side view of the first preferred embodiment of the high thermal conductivity ceramic substrate with protective pads of the present invention, illustrating the corresponding shape relationship between the supporting protective pads and the welding pads, and the corresponding uniform thermal pads and mounting pads Shape relationship.

5 is a schematic top view of the first preferred embodiment of the high thermal conductivity ceramic substrate with protective pads of the present invention.

6 is a schematic side view of a high-power module with a high thermal conductivity ceramic substrate with protective pads according to the present invention.

FIG. 7 is a schematic top view of the second preferred embodiment of the high thermal conductivity ceramic substrate with protective pads according to the present invention.

FIG. 8 is a bottom view of the third preferred embodiment of the high thermal conductivity ceramic substrate with protective pads of the present invention, illustrating the stepped design of the supporting protective pads and uniform thermal conductive pads.

Fig. 9 is a schematic side view of the embodiment of Fig. 8.

10 is a schematic bottom view of the fourth preferred embodiment of the high thermal conductivity ceramic substrate with protective pads of the present invention.

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 present invention is a first preferred embodiment of a high-thermal-conductivity ceramic substrate with protective pads and a high-power module with the substrate. As shown in FIGS. 4 to 5, the high-thermal-conductivity ceramic substrate 1 includes a ceramic substrate, such as aluminum nitride. The substrate body 10, the circuit layer 12, and a plurality of copper thermal pads with gaps formed with each other are exemplified by the material of the substrate body 10, which is defined as the metal heat dissipation mounting block 14. The preferred height of the metal heat dissipation mounting block 14 is greater than 60 microns (micro- meter, μm) The optimal thickness is 150 microns. The circuit layer 12 is arranged on the installation surface 102 above the substrate body 10, and to match the arrangement of a plurality of high-power circuit components, a plurality of welding pads 122 and mounting pads 124 are also provided in this example. The opposite side surface of the substrate body 10 is defined as the mounting heat dissipation surface 104, and the thickness direction of the substrate body 10 is defined as the height direction.

The manufacturing method of the high thermal conductivity ceramic substrate 1 is, for example, firstly forming a copper metal layer on the installation surface 102 and the mounting heat dissipation surface 104 of the substrate body 10 by sputtering, and then respectively install the copper metal layer on the high thermal conductivity ceramic substrate 1 by photolithography. A portion of the surface 102 that does not need to be connected is removed to form the circuit layer 12, and a metal heat-dissipating mounting block 14 with a gap between each other is formed on the mounting heat-dissipating surface 104, both of which can be thickened by electroplating or the like as necessary. Of course, those skilled in the art can also use similar methods other than sputtering to form the above-mentioned two-sided circuit layers and metal heat-dissipating mounting blocks.

Next, solder the bottom electrode of at least one high-power circuit component 2 with a working current of more than tens of amperes on the mounting pad 124. The high-power circuit component 2 is, for example, an electric motorhome produced by Infineon Technologies AG. And the IGBT type AUIRGPS 4067 D1 power management integrated circuit (power management IC) produced by the application of the rail train, 30-80kW power level current up to 160 amperes, and then use the ultrasonic oscillation welding equipment 17 to connect the multiple in this example in parallel with each other One end of the aluminum conductive strip 5 is welded to the welding pad 122 one by one, and the other end is also welded to the top electrode of the high-power circuit element 2 one by one. In this example, if a current of tens of amperes passes through a single metal conductive strip, it will still cause great thermal interference due to some micro-resistance. In addition, considering the space saving of the ceramic substrate, the conductive strips must be arranged approximately concentrically inside and outside.

Among the above-mentioned metal heat-dissipating mounting blocks, the most special feature is that there is a support and protection pad 140 that is stable in oscillation. 122, especially the area of the support and protection pad 140 is not less than the area of the welding pad 122, that is, in the direction of the projection surface perpendicular to the height direction, it can fully cover the welding pad 122 on the installation surface 102 shadow area. Therefore, during the ultrasonic oscillation welding process, no welding oscillation position will exceed the support range of the support and protection pad 140, thereby stably providing stress support, and preventing the substrate body 10 from being suspended due to the ultrasonic oscillation. Supported and broken. However, due to the above-mentioned internal and external arrangement mode of the plurality of conductive bars, only the support underneath can achieve full coverage, so as to ensure the structural integrity of the ceramic substrate body and increase the yield rate.

On the other hand, the metal heat-dissipating mounting block 14 additionally includes a plurality of uniformly thermally conductive pads 142. The uniformly thermally conductive pads 142 here refer to the positions corresponding to the mounting pads 124 on the projection surface perpendicular to the above-mentioned height direction, and The area of the uniform thermal pad 142 is also at least not less than The area of the mounting pad 124 can not only provide stable stress support during the ultrasonic oscillation welding process to prevent the substrate body 10 from cracking under ultrasonic oscillation, but also can fully utilize the heat dissipation area of the mounting pad 124 for heat dissipation, thereby avoiding high-power circuit components. Due to the existence of the gap, the thermal energy of 2 has poor heat conduction in some areas, causing heat energy to accumulate near the gap. On the one hand, it affects the operating environment and performance of the high-power circuit component 2;

In this example, there is a gap 16 between the metal heat-dissipating mounting blocks 14 not greater than 300 microns, and preferably 200 microns, so that the uniform thermal conductive pads 142 can evenly disperse the thermal energy emitted by the high-power circuit element 2 when heated. Moreover, each uniform thermal pad 142 has enough space for thermal expansion without causing warping deformation or even interface peeling due to nowhere to expand, and the substrate body 10 can also avoid the same warping deformation or even microcracking.

In this example, the support and protection pad 140 has a hexagonal shape with an area larger than that of the welding pad 122, and the uniform thermally conductive pad 142 is also a hexagonal shape with an area larger than the area of the mounting pad 124. Therefore, the support and protection pad 140 The area may not be equal to the uniform thermal conductive pad 142. Of course, those skilled in the art can easily infer that as long as the above-mentioned two projection surface requirements for full coverage can be met, the area of the supporting and protecting pad 140 can also be uniformly thermally conductive. The areas of the pads 142 are equal, and the shapes of the supporting and protecting pads 140 and the uniform thermal conductive pads 142 can also be other patterns, which will not hinder the implementation of this case.

Please refer to FIG. 6, in this example, the high thermal conductivity ceramic substrate 1 welded with high-power circuit components 2 is also welded to a copper heat sink fin of a high-power electrical equipment such as an electric motor through a metal heat-dissipating mounting block 14. On the metal heat sink 3, the heat energy emitted by the high-power circuit element 2 can be led out and dissipated more quickly by the heat dissipation fins of the metal heat sink 3. And synchronously use the water cooling device inside the motor to form a high-power module 9 with a high thermal conductivity ceramic substrate 1 with protective pads, because the metallic solder and the copper metal heat dissipation mounting block 14 and the copper metal heat sink 3 have Good contact compatibility and thermal conductivity, and copper has better thermal conductivity (380Wm ^-1 K ^-1 ), so the uniform thermal pad 142 can be absorbed by the heat energy of the high-power circuit element 2 at the fastest rate and then borrowed It is carried and dissipated by the water-cooled device of the water-cooled motor.

In the present invention, metal heat-dissipating mounting blocks spaced apart from each other are arranged on the mounting and heat-dissipating surface of the substrate body, which includes: a support and protection pad that fully covers the welding pad on the projection surface perpendicular to the height direction, and The uniform thermal conductive pads on the projection surface of the above-mentioned mounting pads are completely covered, which can prevent the ceramic substrate from breaking and circuit breakage during ultrasonic vibration welding; and prevent the ceramic substrate and the uniform thermal conductive pads from warping, deforming, or even breaking or peeling.

In the present invention, the mounting and heat dissipation surface of the substrate body of the ceramic substrate is provided by metal welding to thermally connect a metal heat sink with uniform thermal conductive pads across the entire area to form a high-power module with a high thermal conductivity ceramic substrate with protective pads , Can provide better heat conduction to high-power circuit components and ensure proper temperature of the operating environment, thereby increasing the manufacturing yield of ceramic substrates and high-power modules, reducing costs, and prolonging service life.

The second preferred embodiment of the high-thermal-conductivity ceramic substrate with protective pads and the high-power module with the substrate of the present invention is described below. In this embodiment, the same parts as the previous preferred embodiment will not be repeated here, but similar The components of also use similar names and labels, and only explain the differences. The manufacturing method of the high thermal conductivity ceramic substrate in this example, for example, is to first form a copper metal layer on the mounting surface and the mounting heat dissipation surface of the substrate body by electroforming, and then form the circuit on the mounting surface of the high thermal conductivity ceramic substrate by photolithography. Layer, and a metal heat-dissipating mounting block is formed on the mounting heat-dissipating surface.

Please refer to FIG. 7. In this example, the welding pad 122' is a long rectangle to form a terminal bus bar for welding a plurality of aluminum conductive bars 5'. On the contrary, the oscillation in the metal heat-dissipating mounting block 14' The stable support and protection pad 140' is also an elongated rectangle, and is fully covered with the welding pad 122' on the projection surface based on the thickness of the substrate body 10' in the height direction; the mounting pad 124' is a square and uniformly thermally conductive pad 142 'Is a rectangle and fully covers the mounting pad 124' on the projection surface based on the thickness of the substrate body 10'; The original hexagonal shape is supported by the remaining shape of the protective pad 140' and the uniform thermal conductive pad 142'. The metal heat dissipation mounting block 14' except for the supporting protective pad 140', the uniform thermal conductive pad 142' and the adjacent support protection The plurality of metal heat-dissipating mounting blocks 144' other than the pad 140' and the aforementioned uniformly thermally conductive pad 142' are all of a regular hexagonal shape.

In this example, the long rectangular welding pad 122' can be used as a terminal bus bar for welding multiple aluminum conductive strips 5'. For example, a parallel circuit between multiple low-power high-power circuit elements 2'can be realized. To achieve the current output requirement equivalent to a larger power circuit element, to reduce the current of each smaller power circuit element 2'to reduce the heat problem, so that the cost can be reduced and the application range is wider. , Contribute to the market promotion of the product.

The high thermal conductivity ceramic substrate 1'of this example can also be applied to the aforementioned thermoelectric separation circuit board. For example, the method is to pre-cut the FR-4 copper foil printed circuit board 8'with a size slightly larger than the high thermal conductivity. The opening 81' of the ceramic substrate 1', then the high thermal conductivity ceramic substrate 1'is embedded in the opening 81' with an insulating glue 82' to be combined with the printed circuit board 8', and then the copper conductive strip 7'is soldered to the welding pad 122 'And the soldering pad 83' on the printed circuit board 8'to electrically connect the high thermal conductivity ceramic substrate 1'and the printed circuit board 8'to form a thermoelectric separation circuit board.

Of course, as those skilled in the art can easily understand, the support and protection pads and uniform thermal conductive pads in the above embodiments are not limited to the hexagonal design, as shown in the third and fourth embodiments of FIGS. 8 to 10 , Can also choose to be a square support and protection pad 140", evenly thermally conductive pad 142", or a slightly rectangular support and protection pad 140"', uniform thermal conductive pad 142"', or any simple geometric shape, especially as shown in Figures 8 and 9, in order to avoid the gap between the ceramic substrate and the pad. The thermal expansion coefficient of the material is different. Whether it is in the manufacturing and installation process or in the future use process, the interface may peel off due to thermal expansion. At this time, the above-mentioned support and protection pad 140" and uniform thermal pad 142" can also be used The stepped structure 146" is used to disperse the thermal stress, which does not hinder the implementation of the present invention.

In summary, the present invention fully covers the oscillation stabilization support and protection pad of the welding pad on the projection surface perpendicular to the above height direction, which can prevent the ceramic substrate from breaking and circuit disconnection during ultrasonic oscillation welding; corresponding in the above height direction The uniform thermal conductive pads on the above mounting pads can prevent the ceramic substrate and uniform thermal conductive pads from warping, deforming, or even breaking or peeling; the metal radiator that is thermally connected to the uniform thermal conductive pads on the full area by metal welding can provide high-power circuit components Better heat conduction; and the use of long rectangular welding pads as terminal bus bars can further reduce the temperature rise of high-power circuit components and expand the scope of product application; effectively achieving the above-mentioned objectives of the present invention.

However, the above are only preferred embodiments of the present invention, and cannot be used to limit the scope of implementation of the present invention. All simple equivalent changes and modifications made in accordance with the scope of the patent application of the present invention and the content of the description of the invention shall apply. It still falls within the scope of the patent for this invention.

1: High thermal conductivity ceramic substrate

10: Substrate body

102: Set the surface

104: Install the cooling surface

12: Circuit layer

122: Welding pad

124: mounting pad

14: Metal cooling mounting block

140: Support protection pad

142: uniform thermal pad

16: gap

17: Ultrasonic vibration welding equipment

2: High-power circuit components

5: Aluminum conductive strip

Claims (9)

A high-thermal-conductivity ceramic substrate with protective pads for welding to set at least one high-power circuit element with an operating current of at least tens of amperes, and the high-thermal-conductivity ceramic substrate is thermally connected to a metal heat sink, and the high-thermal-conductivity ceramic The substrate includes: A substrate body with a mounting surface and a mounting and heat dissipation surface with a height direction opposite to the mounting surface; At least one circuit layer arranged on the above-mentioned installation surface of the substrate body, the aforementioned circuit layer including at least one metal material welding pad for ultrasonic welding, and at least one mounting pad for welding the above-mentioned high-power circuit components; and A plurality of metal heat-dissipating mounting blocks formed on the mounting and heat-dissipating surface of the substrate body and provided with gaps respectively for thermally connecting to the metal heat sink; wherein, the metal heat-dissipating mounting blocks corresponding to the welding pads in the height direction , Is at least one supporting and protecting pad that fully covers the welding pad on the projection surface perpendicular to the height direction. The high thermal conductivity ceramic substrate with protective pads according to the first item of the scope of patent application, wherein among the metal heat dissipation mounting blocks, at least one metal heat dissipation mounting block corresponding to the mounting pad in the height direction is at least one vertical to the height The projection surface of the direction is fully covered with the uniform thermal conductive pad of the mounting pad. As described in item 1 or 2 of the scope of patent application, the high thermal conductivity ceramic substrate with protective pads, wherein the above-mentioned oscillation stable support and protective pads are rectangular. As described in item 3 of the scope of patent application, the high thermal conductivity ceramic substrate with protective pads, wherein the metal heat dissipation mounting block is a copper layer with a height greater than 60 microns. A high-power module, including: At least one high-power circuit component with a working current of at least tens of amperes; A metal radiator; A high-thermal-conductivity ceramic substrate for soldering the above-mentioned high-power circuit components and thermally connecting the above-mentioned metal heat sink, and the high-thermal-conductivity ceramic substrate includes: A substrate body having an installation surface and a mounting and heat dissipation surface whose height direction is opposite to the installation surface; At least one circuit layer arranged on the above-mentioned installation surface of the substrate body, the aforementioned circuit layer including at least one metal material welding pad for ultrasonic welding, and at least one mounting pad for welding the above-mentioned high-power circuit components; and A plurality of metal heat-dissipating mounting blocks formed on the mounting and heat-dissipating surface of the substrate body and spaced apart from each other for thermally connecting to the metal heat sink; wherein the metal heat-dissipating mounting block corresponding to the welding pad in the height direction is at least one On the projection surface perpendicular to the height direction, the oscillating stabilization support and protection pads are fully covered with the welding pads. As for the high-power module described in item 5 of the scope of patent application, in the metal heat dissipation mounting block, the metal heat dissipation mounting block corresponding to the mounting pad in the height direction is at least one on the projection surface perpendicular to the height direction A uniform thermal pad covering the above mounting pad. For the high-power module described in item 5 or 6 of the scope of patent application, the above-mentioned oscillation stable support and protection pad is rectangular. The high-power module described in item 7 of the scope of patent application, wherein the above-mentioned high-power circuit element is a power management integrated circuit. For example, the high-power module described in item 5 or 6 of the scope of patent application further includes a plurality of high-current metal conductive strips respectively welded to the above-mentioned oscillation stable support protection pad and the above-mentioned high-power circuit element by ultrasonic welding.

Images