Power module and power device

Abstract

The invention relates to a power module and a power device, the power module is arranged on the power device, the power device comprises a first substrate, the first substrate is provided with a power bonding pad, and the power module comprises a plastic package body; the lining plate is arranged on the plastic package body, the lining plate comprises a first surface and a second surface which are oppositely arranged, and the second surface of the lining plate extends towards the top of the plastic package body; the chip is arranged on the first surface of the lining plate; the first end of the metal column is connected with the first surface of the lining plate, the second end of the metal column extends towards the bottom of the plastic package body to form an exposed part, and the exposed part is in compression joint with the power bonding pad. The top space of the plastic package body is not shielded, the heating amount of the chip can be conducted to the second surface of the lining plate from the first surface of the lining plate, and the heating amount of the element of the first substrate can be conducted to the second surface of the lining plate through the metal columns, so that rapid heat dissipation is realized, and the long-term operation reliability of the power module is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of semiconductor devices, and in particular to a power module and a power device. Background Art

[0002] The power module is usually composed of one or more electronic devices (such as transistors, IGBTs, MOSFETs, etc.), and its function is to convert direct current or alternating current into another form of electrical energy to meet specific application requirements. There are usually several ways to install power modules: screw locking, surface mounting, laser welding, snap-on crimping, etc. The above power modules need to be connected to the signal circuit through metal pins, and the power terminals are used to connect to the bus circuit. In terms of connection methods, on the one hand, the pins need to be extended from the packaging structure, and on the other hand, the pins need to be connected to the application circuit by mechanical connection or welding. The pins only serve as electrical connections, and are not friendly to applications in many space-constrained occasions. Secondly, the pins or terminals need to be welded or locked using special tools, which puts more special equipment requirements on the client and increases the customer's production costs.

[0003] In order to solve the above problems, pinless packaging is used in related technologies. Conventional pinless packaging usually refers to QFN packaging (Quad Flat No-leads Package). The basic idea of ​​achieving pinless is to set the pins semi-exposed on the side and bottom of the chip carrier to form a bottom pad structure. During actual installation, the SMT process is used to mount and solder the device to the PCB substrate. During the operation of the power module, the large-size pad at the bottom is used for heat dissipation. This design scheme is only applicable to low-power IC packaging and is not applicable to high-power electronic device packaging. Since the heat generation power of high-power electronic device packaging is relatively high, the heat dissipation capacity of the pad at the bottom of the packaging structure is limited, and the top space of the packaging structure cannot dissipate heat. During long-term operation, it is easy to concentrate heat inside the package body, resulting in reliability problems of the power module. Summary of the invention

[0004] The present application provides a power module and a power device to solve the technical problem that the existing pinless package uses a large-size pad for heat dissipation, the heat dissipation capacity of the pad is limited, the top space of the package structure cannot dissipate heat, and the heat is easily concentrated inside the package during long-term operation, resulting in reliability problems of the power module.

[0005] In a first aspect, the present application provides a power module, which is arranged on a power device, wherein the power device includes a first substrate, and a power pad is arranged on the first substrate. The power module includes:

[0006] Plastic sealing body;

[0007] A liner is arranged on the plastic package body, the liner comprises a first surface and a second surface arranged opposite to each other, and the second surface of the liner extends toward the top of the plastic package body;

[0008] A chip is disposed on the first surface of the backing plate; and

[0009] A metal column, wherein a first end of the metal column is connected to a first surface of the liner, and a second end of the metal column is extended toward the bottom of the plastic package body to form an exposed portion, and the exposed portion is crimped and connected to the power pad.

[0010] In a possible implementation, a first connection hole is provided at the second end of the metal column, an opening is provided on the power pad, a stud is provided on the side of the first substrate facing away from the backing plate, and one end of the stud passes through the opening and is crimped and connected to the first connection hole.

[0011] In a possible implementation manner, a convex pattern is provided on the outer circumference of the metal column.

[0012] In a possible implementation, a plurality of metal columns are provided, and the plurality of metal columns are spaced apart on the lining plate.

[0013] In a possible implementation, a signal contact is disposed on the first surface of the backing plate, a signal probe is disposed on the side of the first substrate facing the backing plate, and an end of the signal contact away from the backing plate contacts an end of the signal probe away from the first substrate.

[0014] In a possible implementation manner, a second connection hole is provided on the plastic package body, and an end of the signal contact facing away from the backing plate is provided in the second connection hole.

[0015] In a possible implementation, there is a first distance between the side of the signal contact facing away from the backing plate and the side of the first substrate facing the backing plate, and there is a second distance between the side of the exposed portion facing away from the backing plate and the side of the first substrate facing the backing plate, and the first distance is greater than the second distance.

[0016] In a possible implementation manner, the chip includes a power chip, a plurality of power chips are provided, and a bonding wire is provided between two adjacent chips.

[0017] In a possible implementation manner, the plastic package at least covers the peripheral side of the metal column, the peripheral side of the chip, the first surface of the liner, and the peripheral side of the liner.

[0018] In a possible implementation, the power module includes a heat sink, a heat sink window is provided on the second surface of the liner, and the heat sink is connected to the heat sink window.

[0019] In a second aspect, the present application provides a power device, including a first substrate and the power module as described above, wherein a power pad is provided on the first substrate, and an exposed portion of a metal column of the power module is crimped and connected to the power pad.

[0020] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0021] The power module and power device provided by the embodiment of the present application, the second end of the metal column extends toward the bottom of the plastic package to form an exposed portion, and the exposed portion is connected to the power pad by crimping, so as to complete the connection between the power circuit of the power module and the busbar circuit of the first substrate. Since the pin design is omitted, the installation process can be greatly simplified, the installation area can be reduced, and space can be saved, thereby achieving the purpose of improving power density, and it is particularly suitable for application scenarios with limited space. Since the second surface of the lining plate extends toward the top of the plastic package, the top of the plastic package is far away from the first substrate, and the top space of the plastic package is unobstructed, the heat generated by the chip can be transferred from the first surface of the lining plate to the second surface of the lining plate, and the heat generated by the components of the first substrate can be transferred to the second surface of the lining plate through the metal column. The heat is exchanged with air or other media on the second surface of the lining plate through natural convection or forced convection, thereby achieving rapid heat dissipation and ensuring the long-term operation reliability of the power module. Compared with the traditional SMT process of mounting and soldering devices to the substrate and using large-size pads for heat dissipation, the heat dissipation efficiency of this power module is greatly improved. There is no need to enlarge the pad size for heat dissipation. More components can be arranged on the side of the first substrate away from the liner, thereby improving the integration level of the power device. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0024] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0025] Figure 1 A schematic diagram of the structure of a power module provided in an embodiment of the present application;

[0026] Figure 2 for Figure 1 A left side view of the power module shown;

[0027] Figure 3 for Figure 2 A partial cross-sectional view of the power module shown;

[0028] Figure 4 for Figure 1 The structural exploded diagram of the power module shown;

[0029] Figure 5 A schematic diagram of an exploded structure of a power device provided in an embodiment of the present application;

[0030] Figure 6 for Figure 5 A schematic diagram of the structure of the power device shown;

[0031] Figure 7 for Figure 6 A partial cross-sectional view of the power device shown.

[0032] Description of reference numerals:

[0033] 1. Power module; 11. Plastic package; 111. Second connection hole; 12. Liner; 121. First surface; 122. Second surface; 1221. Heat dissipation window; 13. Metal column; 131. First end; 132. Second end; 133. Exposed part; 134. First connection hole; 135. Raised pattern; 14. Chip; 15. Signal contact; 16. Bonding wire; 17. Heat sink; 171. Heat sink; 172. Heat dissipation column;

[0034] 2. Power device; 21. First substrate; 22. Power pad; 221. Opening; 23. Stud; 24. Signal probe. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0036] The disclosure below provides many different embodiments or examples to implement different structures of the present invention. In order to simplify the disclosure of the present invention, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present invention. In addition, the present invention can repeat reference numbers and / or letters in different examples. This repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed.

[0037] For ease of description, spatial relative terms may be used herein to describe the relative positional relationship or movement of one element or feature relative to another element or feature as shown in the figure, such as "inside", "outside", "inner side", "outer side", "below", "below", "above", "above", "front", "back", etc. Such spatial relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figure. For example, if the device in the figure undergoes a position flip or a posture change or a motion state change, then these directional indications also change accordingly, for example: an element described as "below other elements or features" or "below other elements or features" will subsequently be oriented as "above other elements or features" or "above other elements or features". Therefore, the example term "below..." may include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions) and the spatial relative descriptors used herein are interpreted accordingly.

[0038] In the prior art, conventional pinless packages usually refer to QFN packages (Quad Flat No-leads Package). The basic idea of ​​achieving pinless is to set the pins semi-exposed on the side and bottom of the chip carrier to form a bottom pad structure. During actual installation, the electronic device is mounted and soldered to the PCB substrate using the SMT process. During the operation of the electronic device, the large-sized pad at the bottom is used for heat dissipation. This design scheme is only applicable to low-power IC packaging and is not applicable to high-power electronic device packaging. Since the heat generation power of high-power electronic device packaging is high, the heat dissipation capacity of the pad at the bottom of the packaging structure is limited, and the top space of the packaging structure cannot dissipate heat. During long-term operation, the heat is easily concentrated inside the package body, resulting in problems with the reliability of the power module. In addition, the heat dissipation capacity of the large-sized pad at the bottom is limited. After being mounted on the first surface of the PCB substrate, the second surface of the PCB substrate cannot be arranged with other components due to the thermal influence of the module, resulting in a low degree of integration of the substrate.

[0039] In order to solve the technical problem that the existing pinless package uses a large-size pad for heat dissipation, the heat dissipation capacity of the pad is limited, the top space of the package structure cannot dissipate heat, and the heat generated during long-term operation is easily concentrated inside the package body, resulting in reliability problems of the power module, the present application provides a power module and a power device, the heat dissipation efficiency is greatly improved, the long-term operation reliability of the power module is ensured, and more components can be arranged on the side of the first substrate away from the liner, thereby improving the degree of integration of the power device.

[0040] Figures 1 to 3 A power module 1 provided in the present application is arranged on a power device 2, the power device 2 includes a first substrate 21, a power pad 22 is arranged on the first substrate 21, the power module 1 includes a plastic package 11, a liner 12, a chip 14 and a metal column 13, the liner 12 is arranged on the plastic package 11, the liner 12 includes a first surface 121 and a second surface 122 arranged opposite to each other, the second surface 122 of the liner 12 extends toward the top of the plastic package 11; the chip 14 is arranged on the first surface 121 of the liner 12; the first end 131 of the metal column 13 is connected to the first surface 121 of the liner 12, the second end 132 of the metal column 13 extends toward the bottom of the plastic package 11 to form an exposed portion 133, and the exposed portion 133 is crimped and connected to the power pad 22.

[0041] It should be noted that the liner 12 can be a ceramic substrate with copper cladding on both sides. The first surface 121 of the liner 12 is copper clad and has a specific circuit pattern, which plays the role of carrying the chip 14, so that the chips 14 form a good electrical connection. The second surface 122 of the liner 12 is copper clad to balance stress and dissipate heat. The circuit pattern of the first surface 121 of the liner 12 includes a power circuit, and the chip 14 is arranged on the first surface 121 of the liner 12 to achieve electrical connection of the power circuit. Of course, the liner 12 can also include other materials similar to the liner 12 used to form an integrated circuit, such as silicon-based, silicon carbide, glass, lithium tantalate or lithium niobate materials.

[0042] It can be understood that the second end 132 of the metal column 13 is extended toward the bottom of the plastic package body 11 to form an exposed portion 133. The exposed portion 133 is connected to the power pad 22 by crimping, thereby completing the connection between the power circuit of the power module 1 and the busbar circuit of the first substrate 21. Since the pin design is omitted, the installation process can be greatly simplified, the installation area can be reduced, and space can be saved, thereby achieving the purpose of improving power density. It is particularly suitable for application scenarios with limited space. Since the second surface 122 of the liner 12 is extended toward the top of the plastic package 11, the top of the plastic package 11 is far away from the first substrate 21, and the top space of the plastic package 11 is unobstructed, the heat generated by the chip 14 can be transferred from the first surface 121 of the liner 12 to the second surface 122 of the liner 12, and the heat generated by the components of the first substrate 21 can be transferred to the second surface 122 of the liner 12 through the metal column 13. The heat is exchanged with air or other media on the second surface 122 of the liner 12 by natural convection or forced convection, thereby achieving rapid heat dissipation and ensuring the long-term operation reliability of the power module 1. Compared with the traditional SMT process of mounting and soldering the device to the substrate and using a large-size pad for heat dissipation, the heat dissipation efficiency of the power module 1 is greatly improved, and there is no need to use the method of enlarging the pad size for heat dissipation. More components can be arranged on the side of the first substrate 21 away from the liner 12, thereby improving the integration of the power device 2.

[0043] Optionally, the first substrate 21 can be a rigid printed circuit board (PCB), and a busbar loop is provided on the first substrate 21. The exposed portion 133 is connected to the power pad 22 by crimping, thereby completing the connection between the power circuit of the power module 1 and the busbar loop of the first substrate 21, thereby realizing the electrical connection between the power module 1 and the first substrate 21.

[0044] The traditional power module 1 needs to be installed on the PCB substrate by screwing, which not only requires additional pin space, but also takes more time and cost. Therefore, the present application provides a stud 23 and a metal column 13 for crimping connection to save installation cost and process flow, and the specific design is described as follows.

[0045] In some embodiments, Figure 3 and Figure 5 As shown, the second end 132 of the metal column 13 is provided with a first connection hole 134, and the first connection hole 134 is coaxially arranged with the metal column 13. The power pad 22 is provided with an opening 221, and a stud 23 is provided on the side of the first substrate 21 away from the backing plate 12, and one end of the stud 23 passes through the opening 221 and is crimped and connected to the first connection hole 134. Specifically, as Figure 6As shown, the side of the power pad 22 facing the metal column 13 is a crimping area, and the exposed portion 133 located at the second end 132 of the metal column 13 is crimped and connected to the crimping area of ​​the power pad 22. Then, one end of the stud 23 is passed through the opening 221 and crimped and connected to the first connecting hole 134. The connection between the drive circuit of the power module 1 and the busbar circuit of the substrate is completed by tightening and crimping the stud 23, which greatly simplifies the installation process, reduces the installation area, saves pin space, and saves installation costs and process flow.

[0046] In the above embodiment, the power circuit of the power module 1 uses the metal column 13 to connect and output with the pad. In some other embodiments, in addition to using nuts, a large-area contact method can also be used. Specifically, the metal column 13 is set in the form of a metal contact, and a fastener is added to the outside of the power module 1 to achieve the purpose of locking with the first substrate 21; or, the metal column 13 is led out in the form of a multi-pin pin, and the pin is connected to the first substrate 21.

[0047] Furthermore, if Figure 4 As shown, the outer peripheral side of the metal column 13 is provided with a raised pattern 135, and the raised pattern 135 can be provided in a strip shape, a block shape or a bump shape, and the present application does not limit this. During the crimping process between the metal column 13 and the first substrate 21 or during the operation of the power module 1, the metal column 13 is easily subjected to external force and rotates relative to the plastic package 11. By providing the raised pattern 135, the friction between the metal column 13 and the plastic package 11 can be enhanced, and rotation and fatigue damage between the metal column 13 and the plastic package 11 can be avoided, thereby ensuring the connection reliability and long-term operation reliability of the metal column 13 and the first substrate 21.

[0048] Furthermore, a plurality of metal pillars 13 are provided, and the plurality of metal pillars 13 are arranged at intervals on the liner 12. Figure 4 As shown, in one example, three metal pillars 13 are provided, and the three metal pillars 13 are arranged at intervals on the lining plate 12. Specifically, two adjacent metal pillars 13 are arranged in a staggered manner. After the metal pillars 13 are crimped and connected with the power pads 22, the force on the entire power module 1 is more balanced. Of course, a plurality of metal pillars 13 can be provided with raised lines 135 to enhance the friction between the metal pillars 13 and the plastic package 11. Of course, the provision of a plurality of metal pillars 13 is also conducive to the conduction of heat of the components of the first substrate 21. The heat generated by the components of the first substrate 21 can be conducted to the second surface 122 of the lining plate 12 through the plurality of metal pillars 13. The heat is heat-exchanged with air or other media on the second surface 122 of the lining plate 12 by natural convection or forced convection, further improving the heat dissipation efficiency of the heat-generating module.

[0049] In some embodiments, Figure 4 and Figure 7 As shown, the first surface 121 of the liner 12 is provided with a signal contact 15, and a signal probe 24 is provided on the side of the first substrate 21 facing the liner 12, and the end of the signal contact 15 away from the liner 12 contacts the end of the signal probe 24 away from the first substrate 21. Since there are no extended pins, the signal loop is directly connected to the peripheral driving circuit through the signal contact 15 inside the plastic package 11, so that the conductive path between the chip 14 and the signal contact 15 is short, and the self-inductance coefficient and the wiring resistance inside the plastic package 11 are very low, thereby reducing the coupling between signals and preventing signal crosstalk.

[0050] In one example, a plurality of signal contacts 15 may be provided. Figure 4 As shown, there are four signal contacts 15 . Specifically, the four signal contacts 15 are grouped in pairs, and the two groups of signal contacts 15 are spaced apart.

[0051] Furthermore, if Figure 3 As shown, the plastic package 11 is provided with a second connection hole 111, and the end of the signal contact 15 facing away from the liner 12 is provided in the second connection hole 111. In order to connect the signal probe 24 on the first substrate 21, the second connection hole 111 is provided to provide a certain installation space for the signal probe 24, and it is also beneficial to position the signal probe 24 during the installation process. The plastic package 11 can limit the signal probe 24 in the horizontal direction, enhance the contact stability between the signal contact 15 and the signal probe 24, and thus ensure the electrical reliability between the chip 14 and the first substrate 21.

[0052] In this embodiment, four signal contacts 15 are provided, so the second connection holes 111 correspond to the signal contacts 15 one by one, and four second connection holes 111 are also provided.

[0053] It should be noted that, in order to ensure the sealing between the signal contact 15 and the plastic package body 11, the side of the signal contact 15 facing away from the liner 12 adopts a pure plane shape. During the injection molding, the signal contact 15 abuts against the mold ejector pin to ensure that the plastic package material fully penetrates without generating overflow and flash. After the mold ejector pin is removed, the second connection hole 111 can be formed on the plastic package body 11.

[0054] Furthermore, if Figure 3As shown, there is a first spacing h1 between the side of the signal contact 15 away from the backing plate 12 and the side of the first substrate 21 facing the backing plate 12, and there is a second spacing h2 between the side of the exposed portion 133 away from the backing plate 12 and the side of the first substrate 21 facing the backing plate 12, and the first spacing h1 is greater than the second spacing h2. Through the above arrangement, the connection surface between the metal column 13 and the first substrate 21 and the connection surface between the signal contact 15 and the signal probe 24 are not on the same plane, thereby increasing the creepage clearance between the two, especially in high-voltage usage scenarios, which can effectively ensure the electrical safety of the power module 1.

[0055] In some embodiments, Figure 4 As shown, the chip 14 includes a power chip 14, and a plurality of power chips 14 are provided, and a bonding wire 16 is provided between two adjacent power chips 14. The material of the bonding wire 16 can be aluminum, copper, etc. The power chip 14 can be set as an IGBT chip 14 which is widely used. The chip 14 can also include a MOSFET chip 14. The plastic package 11 is molded using thermosetting plastic. The basic requirement of the mold is that pores or stratification are not allowed to appear inside the plastic package 11. The plastic package "casts" the bonding wire 16, the chip 14, the metal column 13, and the signal contact 15 on the liner 12. By integrating and packaging a plurality of power chips 14 together, the service life and reliability of the power module 1 are improved, and the power module 1 has a smaller size, higher efficiency, and higher reliability.

[0056] like Figure 4 As shown, in one example, a half-bridge topology structure composed of two chips 14 is used as an example for illustration. In actual application, this structure can be packaged as a multi-core parallel discrete device structure or a Chopper topology module. In addition, the internal chip 14 of this structure is connected to lead out the chip 14 electrode by wire bonding. In actual application, it can include but is not limited to connection by Cu Clip (a process of welding the chip 14 and the pins with copper sheets), DTS (Die top system), etc.

[0057] Furthermore, the plastic package 11 at least covers the peripheral side of the metal column 13, the peripheral side of the chip 14, the first surface 121 of the liner 12, and the peripheral side of the liner 12, and its function is to protect the power module 1. The plastic package 11 can cover the liner 12, the copper-clad conductive layer on the liner 12, the chip 14, etc., to prevent the liner 12 and the chip 14 from being exposed to the air for a long time and causing oxidation due to moisture, and at the same time, it can prevent the power module 1 from being subjected to external mechanical forces or humid environments. The phenomenon of fault or delamination between the liner 12 and the copper-clad conductive layer ensures the electrical performance and reliability of the power module 1, thereby improving the service life of the power device 2.

[0058] The plastic package 11 is encapsulated by a thermosetting resin; the thermosetting resin is preferably an epoxy resin. Compared with other types of thermosetting resins, the epoxy resin has the following advantages: first, the epoxy resin has strong bonding force and high mechanical strength, and plays a good protective role on the chip 14 coated by it; second, there are multiple polar groups in the epoxy resin molecules, such as hydroxyl and ether groups. Due to the polarization of these groups, the epoxy resin molecules and the adjacent surfaces generate electromagnetic attraction, and the epoxy groups form chemical bonds with the metal surface containing active hydrogen and are very firmly bonded. Therefore, the bonding force is particularly strong, and it is particularly suitable for functional semiconductor devices that are mostly made of metal materials; third, because the epoxy resin does not generate small molecules during curing, it has a high density and a low shrinkage rate during curing, about 2%. It is dimensionally stable, and its creep performance is lower than that of polyester and phenolic; fourth, the epoxy resin has good corrosion resistance, while other resins, such as phenolic and polyester, are mostly not alkali-resistant, while the epoxy resin has good alkali resistance and good corrosion resistance to acids and organic solvents. It is also acid-resistant when anhydride is used as a curing agent, so power semiconductor devices coated with epoxy resin can be used in complex environments; more importantly, the thermal stability of epoxy resin reaches above 250°C, which is particularly suitable for use in high-temperature environments.

[0059] In some embodiments, Figure 5 As shown, the power module 1 further includes a heat sink 17 , a heat sink window 1221 is provided on the second surface 122 of the liner 12 , and the heat sink 17 is connected to the heat sink window 1221 .

[0060] The heat generated by the chip 14 can be dissipated to the external environment through the liner 12 and the heat sink 17. The heat sink 17 includes a heat sink 171 and a plurality of heat sink columns 172 arranged on the heat sink 171. The heat sink 172 can be arranged in a needle-shaped, sheet-shaped, or columnar shape. An array of a plurality of heat sink columns 172 is arranged on the side of the heat sink 171 away from the liner 12 to increase the heat dissipation area and improve the heat dissipation efficiency. Since the plastic package 11 is inverted, the top space of the power module 1 is not blocked, so the heat dissipation efficiency of the heat sink 17 is higher.

[0061] By setting the heat dissipation column 172 in conjunction with the heat sink 171, the heat dissipation column 172 can protect the lining plate 12 on the one hand, and on the other hand, the setting of the heat dissipation column 172 can quickly dissipate the heat inside the chip 14 to the heat dissipation column 172 through the heat sink 171, thereby ensuring the heat dissipation effect inside the chip 14. In addition, the setting of multiple heat dissipation columns 172 can also effectively improve the overall structural strength of the power module 1, thereby improving the service life of the power module 1.

[0062] Optionally, the heat dissipation column 172 is made of a metal with excellent thermal conductivity, such as aluminum or copper, and the heat sink 171 can be made of indium or indium silver alloy.

[0063] It should be noted that the ceramic substrate of the liner 12 is a ceramic material whose main component is inorganic non-metallic material and has excellent insulation performance. Among inorganic non-metallic insulation materials, ceramics have excellent thermal conductivity. The ceramic substrate is arranged between the chip 14 and the heat sink 17 and does not affect the conduction of heat. The heat generated by the chip 14 when working can be quickly conducted to the heat sink 8 through the ceramic substrate and the copper cladding on the second surface 122 of the liner 12. At the same time, the chemical properties of the ceramic material are stable. Except for hydrofluoric acid, the ceramic material does not react with other inorganic acids and has strong corrosion resistance. The ceramic material is resistant to high temperature and oxidation, and is very suitable for use in the power semiconductor devices used in high temperature environments for a long time.

[0064] The ceramic substrate of the lining plate 12 is preferably an alumina ceramic substrate or an aluminum nitride ceramic substrate; the alumina ceramic is a ceramic material with aluminum oxide (Al2O3) as the main crystal phase, and its advantages are that it has excellent thermal conductivity, insulation, relatively small high-frequency loss, and good high-frequency insulation. At the same time, its Rockwell hardness reaches HRA80-90, and the hardness is only second to diamond, far exceeding the wear resistance of wear-resistant steel and stainless steel. The wear resistance of the alumina ceramic is equivalent to 266 times that of manganese steel and 171.5 times that of high-chromium cast iron. Under the same working conditions, it can extend the service life of the equipment by at least ten times. Using alumina ceramic as an insulating substrate can effectively extend the service life of the power module; the density of the alumina ceramic is only 3.5g / cm 3 , which is only half of steel, can greatly reduce the overall weight of the device as an insulating substrate of the power module.

[0065] The aluminum nitride ceramic is a ceramic material with aluminum nitride (AlN) as the main crystal phase, and has excellent comprehensive performance. The theoretical thermal conductivity is 320W / (m·K), which has better thermal conductivity than other ceramic materials. It is used in the insulating substrate of the power module to improve the heat dissipation performance of the power module and increase the service life of the chip of the power module, thereby increasing the service life of the power module; while having excellent conductivity, the aluminum nitride ceramic also has the characteristics of reliable electrical insulation, low dielectric constant and loss, non-toxicity, and a thermal expansion coefficient matching that of silicon.

[0066] like Figure 5 As shown, an embodiment of the present application provides a power device 2, including a first substrate 21 and the power module 1 as described above, wherein the exposed portion 133 of the metal column 13 of the power module 1 is crimped and connected to the power pad 22.

[0067] The second end 132 of the metal column 13 is extended to the bottom of the plastic package 11 to form an exposed portion 133. The exposed portion 133 is connected to the power pad 22 by a crimping process, so that the connection between the power circuit of the power module 1 and the busbar circuit of the first substrate 21 can be completed. Since the pin design is omitted, the installation process can be greatly simplified, the installation area can be reduced, and space can be saved, thereby achieving the purpose of improving power density, which is particularly suitable for application scenarios with limited space. Since the second surface 122 of the liner 12 is extended to the top of the plastic package 11, the top of the plastic package 11 is far away from the first substrate 21, and the top space of the plastic package 11 is unobstructed, the heat generated by the chip 14 can be conducted from the first surface 121 of the liner 12 to the second surface 122 of the liner 12, and the heat generated by the components of the first substrate 21 can be conducted to the second surface 122 of the liner 12 through the metal column 13. These heats are heat exchanged with air or other media on the second surface 122 of the liner 12 by natural convection or forced convection, thereby achieving rapid heat dissipation and ensuring the long-term operation reliability of the power module 1. Compared with the traditional SMT process of mounting and soldering devices to the substrate and using large-sized pads for heat dissipation, the heat dissipation efficiency of the power module 1 is greatly improved. There is no need to enlarge the pad size for heat dissipation. More components can be arranged on the side of the first substrate 21 away from the liner 12, thereby improving the integration level of the power device 2.

[0068] Of course, multiple power modules 1 can be provided, and multiple power modules 1 are arranged on the first substrate 21 at intervals, which can improve the working efficiency and working reliability of the power device 2. Figure 5 As shown, in this embodiment, three power modules 1 are arranged at intervals on the first substrate 21 .

[0069] It should be understood that the terms used herein are only for the purpose of describing specific example embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "said" as used herein may also be meant to include plural forms. The terms "include", "comprise", "contain", and "have" are inclusive, and therefore specify the existence of stated features, steps, operations, elements and / or parts, but do not exclude the existence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The method steps, processes, and operations described herein are not interpreted as necessarily requiring them to be performed in the specific order described or illustrated, unless the execution order is clearly indicated. It should also be understood that additional or alternative steps may be used.

[0070] Although the terms first, second, third, etc. can be used in the text to describe multiple elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates, terms such as "first", "second" and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section without departing from the teaching of the example embodiments.

[0071] The foregoing is merely a specific embodiment of the present invention, which enables those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A power module, arranged on a power device, the power device comprising a first substrate, a power pad being arranged on the first substrate, characterized in that: The power module comprises: Plastic sealing body; A lining plate is arranged on the plastic sealing body, the lining plate comprises a first surface and a second surface arranged opposite to each other, and the second surface of the lining plate extends toward the top of the plastic sealing body; A chip is disposed on the first surface of the liner; and A metal column, wherein a first end of the metal column is connected to the first surface of the liner, and a second end of the metal column is extended toward the bottom of the plastic package body to form an exposed portion, and the exposed portion is crimped and connected to the power pad.

2. The power module according to claim 1, characterized in that: A first connection hole is provided at the second end of the metal column, an opening is provided on the power pad, a stud is provided on the side of the first substrate facing away from the liner, and one end of the stud passes through the opening and is crimped and connected to the first connection hole.

3. The power module according to claim 1, characterized in that: The outer peripheral side of the metal column is provided with raised patterns.

4. The power module according to claim 1, characterized in that: There are a plurality of metal columns, and the plurality of metal columns are spaced apart on the lining plate.

5. The power module according to claim 1, characterized in that: A signal contact is disposed on the first surface of the backing plate, a signal probe is disposed on a side of the first substrate facing the backing plate, and an end of the signal contact away from the backing plate contacts an end of the signal probe away from the first substrate.

6. The power module according to claim 5, characterized in that: A second connection hole is provided on the plastic package body, and an end of the signal contact facing away from the liner is provided in the second connection hole.

7. The power module according to claim 5, characterized in that: There is a first distance between the side of the signal contact facing away from the backing plate and the side of the first substrate facing the backing plate, and there is a second distance between the side of the exposed portion away from the backing plate and the side of the first substrate facing the backing plate. The first distance is greater than the second distance.

8. The power module according to claim 1, characterized in that: The chip comprises a power chip, a plurality of the power chips are provided, and a bonding wire is provided between two adjacent power chips.

9. The power module according to claim 1, characterized in that: The plastic package at least covers the peripheral side of the metal column, the peripheral side of the chip, the first surface of the liner, and the peripheral side of the liner.

10. The power module according to claim 1, characterized in that: A heat sink is included, and a heat sink window is provided on the second surface of the liner, and the heat sink is connected to the heat sink window.

11. A power device, characterized in that: The invention comprises a first substrate and a power module according to any one of claims 1 to 10, wherein a power pad is arranged on the first substrate, and an exposed portion of a metal column of the power module is crimped and connected to the power pad.

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