TWI765352B - High thermal conductivity ceramic substrate with protective pad and high-power module with the same - Google Patents

Abstract

A high-thermal-conductivity ceramic substrate with protective pads for soldering and setting at least a large-power circuit element, the high-thermal-conductivity ceramic substrate is thermally connected to a metal radiator, and the high-thermal-conductivity ceramic substrate comprises: a substrate body having a A setting surface and a mounting heat dissipation surface opposite to the setting surface in a height direction; at least one circuit layer arranged on the above-mentioned setting surface of the substrate body, the circuit layer comprising at least one metal welding pad for ultrasonic welding and at least one for the above-mentioned Mounting pads for welding high-power circuit components; a plurality of metal heat dissipation mounting blocks formed on the mounting heat dissipation surface of the substrate body and arranged at intervals from each other for thermally connecting the metal heat sink, including at least one projection surface perpendicular to the above-mentioned height direction Oscillation-stabilized support pads that fully cover the above fusion pads.

Description

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

A high thermal conductivity ceramic substrate, especially a high thermal conductivity ceramic substrate with a special structurally designed protective pad.

With the promotion of environmental awareness, air pollution has been widely reported by the media, making more and more consumers choose electric vehicles to replace traditional vehicles powered by internal combustion engines, such as replacing two-stroke locomotives with electric scooters and replacing traditional cars with electric RVs , and these electric vehicles all rely on high-power electric motors to provide power, so the market demand for high-power power control components is very strong, and it has also caused major suppliers to invest in research and development, such as Renesas Electronics (Renesas Electronics) ) announced the launch of a 100-amp high-current power metal-oxide-semiconductor field-effect transistor (MOSFET) for motor drives in consumer products such as cordless power tools and power-assisted bicycles.

On the one hand, the high energy consumption of the above-mentioned high-power components means that the current efficiency is high, but the high-power components themselves have internal resistance and large operating current, so it is inevitable that a certain proportion of electric energy will be converted into heat energy. If the heat energy of the high-power element cannot be dissipated as soon as possible, the heat energy generated by the high-heat element will accumulate near the high-power element, making the operating environment of the high-heat element very unsatisfactory and affecting its performance. At present, the more commonly adopted solution is to use ceramic material as the insulating material layer of the circuit substrate, and the ceramic substrate as the circuit board One, it has a thermal expansion coefficient close to that of semiconductors and high heat resistance, especially compared with traditional circuit substrates such as FR4 and other materials, it has a good thermal conductivity, suitable for products with high heat generation, and its high hardness and good workability , high dimensional accuracy, high insulation resistance, and strong circuit pattern adhesion, coupled with abundant material sources and easy access, so it has become the first choice for the substrate of the printed circuit used to configure high-power components.

The most common ceramic materials are Direct Bonded Copper ( ^DBC ) substrates made of aluminum oxide (Aluminum ^Oxide , Al2O3). Under the crystal structure, there are 20 to 27Wm ^-1 K ^-1 . Other common ceramic material 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, such substrates are sometimes called high-power printed circuit substrates (Power Electronic Substrate).

The aluminum conductive strip will react with oxygen quickly to form an oxide film in the air, which can prevent further oxidation, so the aluminum conductive strip is a commonly used wire-bonding material for the brush circuit of high-power components. However, due to the strong oxidation activity of aluminum, an oxide layer will rapidly form 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 on the copper welding pad, as shown in Figure 1. As shown, the aluminum conductive strips 85 and the welding pads 86 are generally welded using, for example, ultrasonic oscillation welding equipment 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 rupture during ultrasonic vibration, causing the problem of circuit breakage. Therefore, it has been difficult to increase the manufacturing volume rate, which directly reduces the production capacity and improves the cost.

In addition, although high-power components can be easily soldered on the pads arranged on the surface of the ceramic substrate, it is easy to generate excessive thermal energy accumulation due to the printed circuit board and the The thermal expansion coefficients of circuit components are different. The thermal expansion coefficients of metal copper and aluminum are 16.5 and 23ppm/K, while the ceramic materials alumina, aluminum nitride and silicon nitride are about 7, 4.5 and 3.5ppm/K respectively. When the thermal expansion coefficient difference between the substrate and the bonded metal layer is too large, the thermal expansion and contraction of the thermally conductive pad 90 will be greater than that of the substrate body 87 under repeated thermal expansion and contraction in a high-temperature soldering environment or operating environment. 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, and it will inevitably cause the risk of damage to the contacts due to thermal stress. High-efficiency heat dissipation methods are usually required. In order to effectively solve the problem of thermal energy accumulation.

To this end, the following methods are commonly used at present: one is to configure a large range of vacant space between high-power circuit components and other circuit components, and to dissipate the emitted heat energy to the periphery of the printed circuit board through thermal convection or thermal radiation Second, as shown in the high-power component 88 in FIG. 2, on the back of the ceramic substrate body 87 welded with the high-power circuit element 89, for example, copper thermally conductive pads 90 are laid on the backside. , and then thermally connect the metal heat sink 92 (Heat-Sink) with better thermal conductivity through the thermal conductive adhesive 91 and other materials 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 larger than that of the ceramic substrate, this This method will cause the substrate body 87 to warp and deform or even break, and the thermally conductive pads 90 will also warp and deform or even peel off, resulting in low heat dissipation efficiency, and the thermal conductivity of the thermally conductive adhesive 91 itself is much lower than that of metal. If a fan is installed at the far end away from the heat-generating electronic components, the 92% heat conduction effect of the metal heat conductor will also be greatly reduced.

In addition, generally, on the back of the heat-conducting circuit board to which high-power components are welded, a layer such as a copper layer is often grown on the back as a heat-conducting pad 90 by means such as sputtering, so as to be used as a heat-dissipating pad 90, which is also made of copper. 92 is properly combined, and the heat 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 to include Mounting pads 93 for soldering high-power circuit elements 89 and welding pads 86 for soldering aluminum conductive strips 85 ;

Please refer to FIG. 2 , in order to overcome this problem, the applicant further divides the whole copper layer into multiple pieces of copper layer blocks 95 such as hexagonal copper layers with smaller areas and slight gaps 94 . The upper ceramic substrate and the lower fin-type metal heat sink maintain good bonding and thermal contact. On the other hand, when the copper layer block 95 expands and contracts, the slight gap 94 can be used as a bridge or rail expansion joint. A buffer zone is provided so that the difference in thermal expansion between the copper layer block 95 and the ceramic will not cause structural damage such as warpage peeling.

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

Especially as shown in FIG. 3 , the applicant is better at pre-forming openings 97 slightly larger than the size of the ceramic substrate in a multilayer printed circuit board 96 such as FR-4, and then inlaying the high thermal conductivity ceramic substrate 98 with insulating adhesive 99 by curing and adhering. 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 with the circuit on the ceramic substrate. They are connected to each other to form a special composite circuit board.

A circuit board with this structure is called a thermoelectric separation circuit board. A 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 drawing, so as to prevent other circuit elements in the FR-4 copper foil printed circuit board 96 from being subjected to a large amount of heat emitted by the high-power circuit element 89 On the other hand, the complex circuit design does not need to accommodate the simple structure of the ceramic substrate, and can be fully utilized in the multi-layer board, miniaturized as much as possible, and saves relatively expensive ceramic substrate materials.

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

One 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 product yield.

Another object of the present invention is to provide a highly thermally conductive ceramic substrate with protective pads for fully dissipating heat during operation of high-power circuit elements to avoid warping 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 heat-conducting efficiency between the uniform thermal-conductivity pads and the metal heat-dissipating fins, and make the thermal energy emitted by the high-power components faster. Escape without accumulation to improve its working efficiency.

In order to achieve the above purpose, the present invention discloses a high thermal conductivity ceramic substrate with protective pads for welding at least one high-power circuit element with an operating current of tens of amperes, and the high thermal conductivity ceramic substrate is thermally connected to a metal for heat dissipation. and the high thermal conductivity ceramic substrate includes: a substrate body having a setting surface and a mounting surface opposite to the setting surface in a height direction hot surface; at least one circuit layer arranged on the above-mentioned setting surface of the substrate body, the above-mentioned circuit layer includes at least one welding pad of metal material for ultrasonic welding, and at least one mounting pad for welding the above-mentioned high-power circuit components; and a plurality of forming A metal heat-dissipating mounting block that is mounted on the heat-dissipating surface of the substrate body and is 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 vertical The above-mentioned projection surface in the height direction completely covers the above-mentioned vibration-stable support and protection pads of the above-mentioned welding pads. and at least one uniform thermal conductive pad that fully covers the mounting pad on a projection plane 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 formed, which includes: at least one high-power circuit element with an operating current of tens of amperes; a Metal radiator; a high-thermal-conductivity ceramic substrate for soldering the high-power circuit elements and thermally connecting the metal radiator, the high-thermal-conductivity ceramic substrate includes: a substrate body with a setting surface and a height direction opposite to the metal radiator. The installation and heat dissipation surface of the setting 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 welding pad for ultrasonic welding, and at least one for welding the above-mentioned high-power circuit components. Mounting pad And a plurality of metal heat dissipation mounting blocks formed on the above-mentioned mounting heat dissipation surface of the above-mentioned substrate body and spaced apart from each other for thermally connected to the above-mentioned metal heat sink; wherein, the metal heat dissipation mounting block corresponding to the above-mentioned welding pad in the above-mentioned height direction is At least one vibration-stable support protection pad that fully covers the welding pad on a projection plane perpendicular to the height direction. and at least one uniform thermal conductive pad that fully covers the mounting pad on a projection plane 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 fully covering the above-mentioned welding pad on the projection surface perpendicular to the above-mentioned height direction, the vibration-stable support and protection pads are used to prevent the ceramic substrate from being broken during ultrasonic vibration welding and circuit damage. ; And by the uniform thermal conductive pad corresponding to the above-mentioned mounting pad in the above-mentioned height direction, the ceramic substrate and the uniform thermal conductive pad are prevented from being warped, deformed or even broken, and by the complete coating of the uniform thermal conductive pad below, the high power The heat generated by the circuit components can be smoothly and effectively dissipated to the heat sink under the ceramic substrate, thereby ensuring the proper temperature of the operating environment and effectively ensuring the work efficiency and service life.

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

10, 10', 87: Substrate body

102: Setting Faces

104: Install the cooling surface

12: circuit layer

122, 122', 86: welding pad

124, 124', 93: Mounting pads

14, 14': Metal heat dissipation mounting block

140, 140', 140", 140''': Support protection pads

142, 142', 142", 142''': uniform thermal pad

144': The rest of the metal heat dissipation mounting block

146": stepped structure

16, 16', 94: Gap

17, 84: Ultrasonic Oscillation 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: PCB

81', 97: Opening

82', 99: insulating material

83': Solder Pad

88: High-power components

9: High power module

90: thermal pad

91: thermal paste

95: Copper layer block

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

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

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 according to the present invention, illustrating the corresponding shape relationship between the supporting protective pads and the welding pads, and the correspondence between the uniform thermally conductive pads and the mounting pads shape relationship.

FIG. 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 having protective pads according to the present invention.

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

8 is a schematic bottom view of the third preferred embodiment of the high thermal conductivity ceramic substrate with protective pads of the present invention, illustrating a stepped design for supporting the protective pads and the uniform thermally 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 represented by similar label representation.

A first preferred embodiment of a high thermal conductivity ceramic substrate with protective pads and a high-power module with the substrate of the present invention, as shown in FIG. 4 to FIG. 5 , the high thermal conductivity ceramic substrate 1 includes a The substrate body 10, the circuit layer 12, and the material of the substrate body 10 and the circuit layer 12 are illustrated as a plurality of copper thermally conductive pads with gaps formed with each other, which are defined as metal heat dissipation mounting blocks 14. The preferred height of the metal heat dissipation mounting blocks 14 is greater than 60 microns (micro- meter, μm) optimal thickness is 150 μm. The circuit layer 12 is the setting surface 102 disposed above the substrate body 10 , and in order to match the setting of a plurality of high-power circuit elements, a plurality of welding pads 122 and mounting pads 124 are also provided in this example. The opposite side of the substrate body 10 is defined as the mounting heat dissipation surface 104 , and the direction of the thickness of the substrate body 10 is defined as the height direction.

The manufacturing method of the high thermal conductivity ceramic substrate 1, for example, firstly forms a copper metal layer on the entire surface 102 and the mounting heat dissipation surface 104 of the substrate body 10 by sputtering, and then uses photolithography to respectively install the high thermal conductivity ceramic substrate 1. The circuit layer 12 is formed by removing some non-conductive areas on the surface 102 , and the metal heat dissipation mounting blocks 14 with gaps are formed on the mounting heat dissipation surface 104 . 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 dissipation mounting blocks.

Next, the bottom electrode of at least one high-power circuit element 2 with an operating current of more than tens of amperes is welded on the mounting pad 124 . and the application of rail trains, IGBT type AUIRGPS 4067 D1 power management IC (power management IC) with 30-80kW power stage current up to 160 amps, and then the ultrasonic oscillation welding equipment 17 is used to connect multiple strips in parallel with each other in this example 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 flows through a single metal conductive strip, it will still cause great thermal interference due to a small resistance. Considering the space saving of the ceramic substrate, the conductive strips must be arranged in a roughly concentric manner.

Among the above-mentioned metal heat dissipation mounting blocks, the most special feature is that there are support and protection pads 140 with stable oscillation. 122 position, 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 above-mentioned height direction, it can fully cover the welding pad 122 on the setting 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 pads 140 , thereby stably providing stress support, and preventing the substrate body 10 from being suspended due to ultrasonic oscillation. support and rupture. Due to the above-mentioned internal and external arrangement modes of the plurality of conductive strips, only the support below can achieve full coverage, so as to ensure the structural integrity of the ceramic substrate body and improve the yield.

On the other hand, the metal heat dissipation mounting block 14 additionally includes a plurality of uniform thermally conductive pads 142. The uniform thermally conductive pads 142 here refer to the positions corresponding to the mounting pads 124 on the projection plane 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 stably provide stress support during the ultrasonic oscillation welding process to prevent the substrate body 10 from breaking under the ultrasonic oscillation, and 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 thermal conductivity in some areas, resulting in the accumulation of thermal energy near the gap. On the one hand, it affects the operating environment and performance of the high-power circuit element 2, and on the other hand, the stable connection of the interface is damaged.

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

In this example, the support and protection pads 140 are in a hexagonal shape with an area larger than that of the welding pads 122 , and the uniform thermally conductive pads 142 are also in a hexagonal shape with an area larger than that of the mounting pads 124 . The area is not necessarily 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 requirements for full coverage on the two projection surfaces are met, the area of the supporting protection pad 140 can also be uniformly thermally conductive. The areas of the pads 142 are equal, and the shapes of the support and protection pads 140 and the uniform thermally conductive pads 142 can also be other shapes, which does not hinder the implementation of this case.

Referring to FIG. 6 , in this example, the above-mentioned high thermal conductivity ceramic substrate 1 welded with high-power circuit components 2 is also welded to a copper heat-dissipating 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 quickly conducted and dissipated 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 metal solder, the metal heat dissipation mounting block 14 made of copper and the metal heat sink 3 made of copper have Good contact compatibility and thermal conductivity, and copper has a better thermal conductivity (380Wm ^-1 K ^-1 ), so the uniform thermal pad 142 can receive the heat energy absorbed from the high-power circuit element 2 at the fastest rate and then borrow it. Entrained and dissipated by the water cooling 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 comprises: supporting and protecting the pads by fully covering the welding pads on the projection surface perpendicular to the height direction, and a support and protection pad in the height direction The uniform thermal conductive pads on the projection surface of the above-mentioned mounting pads are fully covered, which can prevent the ceramic substrate from breaking and circuit disconnection during ultrasonic oscillation welding;

In the present invention, the mounting heat dissipation surface of the substrate body of the ceramic substrate is provided with a metal heat sink by means of metal welding to thermally connect the entire area of a metal radiator with evenly thermally conductive pads to form a high-power module with a high thermal conductivity ceramic substrate with protective pads , which can provide better heat conduction for high-power circuit components and ensure an appropriate temperature of the operating environment, thereby increasing the manufacturing yield of ceramic substrates and high-power modules, reducing costs, and extending 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 as follows, and the same parts in this embodiment as the previous preferred embodiment will not be repeated here, and are similar. Elements of the same type also use similar names and numbers, and only the differences are explained. The manufacturing method of the high thermal conductivity ceramic substrate in this example, for example, firstly forms a copper metal layer on the setting surface of the substrate body and the mounting and heat dissipation surface by electrical bonding, and then forms circuits on the setting surface of the high thermal conductivity ceramic substrate by photolithography. layer, and a metal heat dissipation mounting block is formed on the mounting heat dissipation surface.

Referring 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 vibration in the metal heat dissipation mounting block 14' The stable support and protection pads 140 ′ are also elongated rectangles, and fully cover the welding pads 122 ′ on the projection surface based on the height direction of the thickness of the substrate body 10 ′; the mounting pads 124 ′ are square and uniformly thermally conductive pads 142 ' is a rectangle and fully covers the mounting pads 124' on the projection surface of the height direction based on the thickness of the substrate body 10'; the metal heat dissipation mounting blocks 14' adjacent to the support protection pads 140' and the uniform thermally conductive pads 142' are also respectively The original regular hexagonal shape is the residual shape of the support and protection pads 140' and the uniform thermally conductive pads 142'. In the metal heat dissipation mounting block 14', in addition to the support and protection pads 140', the uniform thermally conductive pads 142' and the support protection A plurality of other metal heat dissipation mounting blocks 144 ′ other than the pads 140 ′ and the above-mentioned uniform thermally conductive pads 142 ′ are all regular hexagonal.

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

The high thermal conductivity ceramic substrate 1' of this example can also be applied to the above-mentioned thermoelectric separation circuit board. For example, a printed circuit board 8' of FR-4 copper foil is pre-cut by laser to form 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 insulating glue 82' and combined with the printed circuit board 8', and then soldered to the welding pad 122 with copper conductive strips 7' ' and the solder pads 83' on the printed circuit board 8' to electrically connect the high thermal conductivity ceramic substrate 1' with the printed circuit board 8' to form a thermoelectrically separated circuit board.

Of course, as can be easily understood by those skilled in the art, the support and protection pads and the uniform thermally conductive pads in the above embodiments are not limited to hexagonal designs, as shown in the third and fourth embodiments of FIGS. 8 to 10 . , can also be selected as square support pads 140", uniform thermal pads 142", or slightly rectangular support and protection pads 140"", uniform thermally conductive pads 142", or any simple geometry, especially as shown in Figures 8 and 9, in order to avoid the The thermal expansion coefficients of the materials are different. No matter in the manufacturing and installation process or the future use process, the interface may be peeled off due to thermal expansion. The step-like structure 146'' is used to disperse thermal stress, which does not hinder the implementation of the present invention.

To sum up, the present invention fully covers the vibration stable support protection pad of the welding pad on the projection plane perpendicular to the height direction, which can prevent the ceramic substrate from breaking and circuit disconnection during ultrasonic vibration welding; corresponding to the above height direction. The uniform thermal conductive pads used in the above mounting pads can prevent the ceramic substrate and the uniform thermal conductive pads from warping, deformed, or even broken or peeled off. 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 achieve the above objectives of the present invention.

However, the above are only the preferred embodiments of the present invention, which cannot limit the scope 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 contents of the description of the invention should be It still falls within the scope of the patent of the present invention.

1: High thermal conductivity ceramic substrate

10: Substrate body

102: Setting Faces

104: Install the cooling surface

12: circuit layer

122: Fusion pad

124: Mounting pads

14: Metal cooling mounting block

140: Support protection pad

142: Uniform thermal pad

16: Gap

17: Ultrasonic Oscillation Welding Equipment

2: High-power circuit components

5: Aluminum conductive strip

Claims (9)

A high thermal conductivity ceramic substrate with protective pads, for welding 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 substrate The substrate includes: a substrate body with a setting surface and a mounting heat dissipation surface opposite to the setting surface in a height direction; at least one circuit layer arranged on the setting surface of the substrate body, and the circuit layer includes at least one metal material for ultrasonic waves Welded welding pads, and at least one mounting pad for soldering the above-mentioned high-power circuit components; and a plurality of metal formed on the above-mentioned mounting and heat-dissipating surfaces of the above-mentioned substrate body and respectively leaving a gap with each other for thermally connecting to the above-mentioned metal heat sink. A heat-dissipating mounting block; wherein, the metal heat-dissipating mounting block corresponding to the welding pad in the height direction is at least one vibration-stable support protection pad that fully covers the welding pad on a projection plane perpendicular to the height direction. The high thermal conductivity ceramic substrate with protective pads according to claim 1, wherein at least one metal heat dissipation mounting block corresponding to the mounting pad in the height direction is fully covered on the projection surface perpendicular to the height direction Uniform thermally conductive pads of the above mounting pads. High thermal conductivity ceramic base with protective pads as described in claim 1 or 2 The plate, wherein the above-mentioned oscillation stabilization support protection pads are rectangular. The high thermal conductivity ceramic substrate with protective pads according to claim 3, wherein the metal heat dissipation mounting block is a copper layer with a height greater than 60 microns. A high-power module, comprising: at least one high-power circuit element with an operating current of at least tens of amperes; a metal radiator; a high-thermal-conductivity ceramic substrate for welding the high-power circuit element and thermally connected to the metal radiator, The high thermal conductivity ceramic substrate includes: a substrate body with a setting surface and another mounting heat dissipation surface whose height direction is opposite to the setting surface; at least one circuit layer arranged on the setting surface of the substrate body, and the circuit layer includes at least one Metal welding pads for ultrasonic welding, and at least one mounting pad for welding the above-mentioned high-power circuit components; and a plurality of metal formed on the above-mentioned mounting and heat-dissipating surfaces of the above-mentioned substrate body and spaced apart from each other for thermally connecting to the above-mentioned metal heat sink. A heat-dissipating mounting block; wherein, the metal heat-dissipating mounting block corresponding to the welding pad in the height direction is at least one vibration stable supporting protection pad that fully covers the welding pad on a projection plane perpendicular to the height direction. The high-power module according to claim 5, wherein in the above-mentioned height direction The metal heat-dissipating mounting block corresponding to the mounting pad is at least one uniform heat-conducting pad that fully covers the mounting pad on a projection plane perpendicular to the height direction. The high-power module according to claim 5 or 6, wherein the above-mentioned vibration-stabilizing support and protection pads are rectangular. The high-power module of claim 7, wherein the high-power circuit element is a power management integrated circuit. The high-power module as described in claim 5 or 6 of the claimed scope further comprises a plurality of high-current metal conductive strips welded to the above-mentioned oscillation stable support protection pad and the above-mentioned high-power circuit element respectively by ultrasonic welding.

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