Power module with efficient heat dissipation performance and independent packaging device

Abstract

The utility model relates to a power module with high heat dissipation performance and comprising an independent packaging device. The power module comprises a module tube shell, at least one unit module and at least one conductive heat dissipation component, the at least one unit module is arranged in the module tube shell; each unit module comprises a substrate and at least one independent packaging device; the at least one independent packaging device is mounted on the substrate and is electrically connected with the mounted substrate; the unit modules are electrically connected; an insulating protection layer covers the interior of the module tube shell, and all the unit modules are sealed in the module tube shell by the insulating protection layer; the at least one conductive heat dissipation member is located inside or outside the insulating protection layer and is electrically connected with the unit module and the independent packaging device. According to the utility model, the heat dissipation performance is effectively improved, and the situation that module packaging cannot be reworked can be broken through.

Description

Technical Field

[0001] The utility model relates to the technical field of integrated circuit manufacturing, in particular to a power module with high-efficiency heat dissipation performance and comprising independent packaging devices. Background Art

[0002] With the development trend of high frequency and high speed, high voltage and high current, high temperature, high heat dissipation and high reliability of IGBT / SiC power modules, the IGBT / SiC power module packaging technology based on packaging structure and packaging materials is also constantly updated. Compared with the packaging structure, the characteristics of IGBT / SiC power module packaging materials are mainly high heat dissipation and high reliability requirements of ceramic copper-clad substrates, heat dissipation base plates, adhesive materials, interconnection materials and potting materials to meet the application requirements of IGBT / SiC power modules.

[0003] In order to meet the development needs of high frequency, high speed, high voltage, high current, high temperature, high heat dissipation and high reliability of power modules, IGBT / SiC power modules have derived many advanced packaging structures, such as direct wire bonding (DLB) structure, Skin structure, embedded structure, Semikon planar interconnection technology, 2.5D structure, chip-on-chip (CoC) structure, 3D wafer-level packaging structure, etc. However, basically all of them use ceramic substrate as the main heat dissipation channel, and each terminal output as the auxiliary heat dissipation channel. For the requirements of high voltage / high frequency switching speed, ultra-high frequency electrical suppression and heat dissipation problems, and the problems of multi-chip series and parallel or partial series and parallel loss have become difficult problems that must be solved.

[0004] The current mainstream module packaging heat dissipation structure implementation solutions and electrical connection solutions in the industry are mainly as follows:

[0005] The copper-clad ceramic plate at the bottom of the module and the heat dissipation base plate are used as the main heat dissipation channel, and the electrical terminal output / chip top silicone and air transmission are used as auxiliary heat dissipation channels;

[0006] Adopt the structure of multi-chip series-parallel or partial series-parallel to realize the connection of active and passive devices such as different diodes / transistors;

[0007] The above structure has the following deficiencies:

[0008] The chip's working heat area is mainly in the design circuit layer, and the overall heat dissipation channel is on the upper layer of the chip, not the bottom of the chip. In order to effectively and quickly dissipate heat when the chip is working, there are the following problems and challenges:

[0009] 1. The chip thickness needs to be as thin as possible so that the heat can be transferred to the back of the chip through the silicon base or SIC base, which increases the technical difficulty and process cost of the industry, resulting in low yield and increased equipment investment costs.

[0010] 2. The bottom of the chip must be made of high thermal conductivity solder or sintered silver and other high thermal conductivity materials to quickly transfer the heat from the back of the chip to the copper-clad ceramic plate underneath (the ceramic plate needs to be combined with the chip heat requirements and select processes with different thermal conductivity coefficients, such as DBC / AMB, which needs to be doped with high thermal conductivity metals such as zirconium oxide, etc.), resulting in an increase in the cost of special materials;

[0011] 3. A metal heat sink needs to be selectively added to the bottom of the chip to remove the internal heat to the outside of the product, which results in the need to add an additional high-cost heat sink.

[0012] As for the existing chip connection relationship, because the main body adopts a series-parallel or partial series-parallel structure, there is a problem of low quality yield or the product cannot be reworked and repaired if one is damaged, resulting in low overall product yield, as well as increased product costs and market prices, and reduced market competitiveness. Utility Model Content

[0013] In view of the current technical barriers such as low module packaging yield, high overall cost, poor heat dissipation transfer channel, and poor stress effect, the existing structure cannot effectively improve the temperature transfer of the chip itself, and the chip series-parallel or partial series-parallel structure cannot achieve board disassembly operations. In view of the above shortcomings, it is impossible to well cover the market application of silicon carbide / IGBT / gallium nitride and other chips in the entire module market.

[0014] The purpose of this utility model patent is to provide a power module with high efficiency heat dissipation performance and independent packaging devices, including a module tube shell, at least one unit module and at least one conductive heat dissipation component;

[0015] At least one of the unit modules is disposed in the module shell;

[0016] The unit modules each include a substrate and at least one independent packaging device;

[0017] At least one independent packaged device is mounted on the substrate and is electrically connected to the mounted substrate respectively;

[0018] The unit modules are electrically connected;

[0019] The module shell is covered with an insulating protective layer, and the insulating protective layer seals all unit modules in the module shell;

[0020] At least one conductive heat dissipation component is located inside or outside the insulating protection layer and is electrically connected to the unit module and the independent packaging device.

[0021] Specifically, the substrate is a heat dissipation insulating base plate, one side of the heat dissipation insulating base plate is provided with a conductive circuit, and the conductive circuit is electrically connected to all packaging devices located in the same unit module.

[0022] Furthermore, a metal connection layer is provided on the other side of the heat dissipation insulation base plate.

[0023] Furthermore, a heat sink is provided on the module tube shell, and the heat sink is connected to the metal connection layer to achieve heat conduction.

[0024] Optionally, the heat dissipating insulating base plate is ceramic.

[0025] Optionally, the insulating protective layer is a protective glue.

[0026] Specifically, the packaged device includes a carrier board, at least one chip, a conductive heat sink and a plastic package;

[0027] The chip is inverted on the carrier;

[0028] The conductive heat sink is electrically connected to the pins on the chip and the carrier board respectively;

[0029] The plastic package body covers the entire packaged device, and the upper surface of the conductive heat sink and the lower surface of the carrier board are exposed outside the plastic package body.

[0030] Optionally, when the number of chips in a single packaged device is 1, the chip is one of an IGBT power chip, a SIC power chip, a GAN power chip, and a MOSFET power chip.

[0031] Optionally, when the number of chips in a single packaged device is greater than 1, the chip is a combination of one or more of an IGBT power chip, a SIC power chip, a GAN power chip, and a MOSFET power chip.

[0032] Optionally, when the number of chips in a single packaged device is greater than 1, the chip is one or more of an IGBT power chip, a SIC power chip, a GAN power chip, a MOSFET power chip, combined with one or more diodes.

[0033] Optionally, the power module is provided with one or more of passive components, active components and sensors according to electrical function requirements.

[0034] The power module with high heat dissipation performance and independent packaging components of the utility model has the following advantages compared with the prior art:

[0035] (1) Product cost: Two main channels are used for heat dissipation, which reduces the pressure on the chip thickness structure, process cost and equipment investment cost; the strict requirements on the thermal conductivity of the copper-clad ceramic plate at the bottom of the chip are reduced, and materials with ordinary thermal conductivity can be selected as replacements, reducing the cost of material selection; and the selection of the bottom heat dissipation base plate is reduced, effectively reducing the cost pressure of the heat dissipation base plate;

[0036] (2) Heat dissipation effect: Add a double-sided heat dissipation channel device packaging structure and adopt a metal area expansion method to achieve the largest area welding of the rear-mounted heat sink, and achieve high-current heat dissipation through the top heat dissipation channel metal bridge, improve the heat dissipation transmission efficiency, and optimize the chip operation speed; (The top bridge can be established as a whole, single, multi-segment or multiple bridges according to stress or space problems);

[0037] (3) Stress effect: Etching or stamping the thermally conductive metal in multiple shapes can effectively transfer stress concentration points and distribute the effects of stress singularities. In addition, it can increase the bonding area between the filler and the metal, thereby improving welding firmness and reliability.

[0038] (4) Through device packaging (internal wire bonding or flip-chip connection or chip stacking interconnection structure), the lead-out terminals are connected to the circuit substrate such as ceramic copper-clad boards or PCB boards to achieve thermal / electrical physical performance interconnection, eliminating the interconnection structure of the chip's own wire bonding, effectively solving the problem of all chips being damaged if one chip is damaged. If a product fails, it can be repaired and stopped in time by removing the board and replacing the device package;

[0039] (5) The top of the module package can be equipped with a protective cover with or without holes;

[0040] (6) Effectively design the creepage distance d and avoid the risk of high voltage / high current crosstalk by controlling the spacing between device package terminals;

[0041] (7) The inside of the module shell can be selectively filled with protective glue or other high-reliability filling resin materials to improve the reliability performance of the module.

[0042] At present, the process methods and applications of this kind of heat dissipation structure and internal connection structure are somewhat different from the solutions in the field of semiconductor packaging. It can not only effectively improve the heat dissipation performance, but also break through the situation that the module packaging cannot be reworked, effectively improve the market acceptance of module packaging, increase the popularity of module packaging, reduce market costs, and break the existing technical barriers and process difficulties. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 The structure of a power module with high heat dissipation performance including independent packaging devices of this embodiment is schematically shown. Figure 1 ;

[0044] Figure 2 The structure of the unit module in this embodiment is shown in FIG. Figure 1 ;

[0045] Figure 3 The structure of the packaged device in this embodiment is schematically shown in FIG. Figure 1 ;

[0046] Figure 4 This is a schematic diagram of the product after step S1 in this embodiment is completed;

[0047] Figure 5 This is a schematic diagram of the product after step S2 in this embodiment is completed;

[0048] Figure 6 This is a schematic diagram of the back side of the chip after the second layer of connection material is printed in step S3 of this embodiment;

[0049] Figure 7 This is a schematic diagram of the product after step S3 in this embodiment is completed;

[0050] Figure 8 This is a schematic diagram of the product after step S4 in this embodiment is completed;

[0051] Fig. 9 This is a schematic diagram of a product in which, in step S5 of this embodiment, after the conductive heat dissipation component is electrically connected to the packaged device, the electrodes formed by the conductive heat dissipation component and the electrodes formed by the conductive circuit on the ceramic copper-clad board are led out using a metal conductive medium to achieve internal and external electrical connection;

[0052] Fig.10 A schematic diagram of a power module with high heat dissipation performance including independent packaging devices according to the present embodiment Figure 2 ;

[0053] Fig.11 The structure of the unit module in this embodiment is shown in FIG. Figure 2 ;

[0054] Fig.12 The structure of the packaged device in this embodiment is schematically shown in FIG. Figure 2 . DETAILED DESCRIPTION

[0055] The specific implementation of the utility model patent is further described in detail below in conjunction with the accompanying drawings.

[0056] Example

[0057] like Figure 1 As shown, a power module with high efficiency heat dissipation performance including independent packaging devices,

[0058] It includes a module tube shell 1, four unit modules 2 and four conductive heat dissipation components 3;

[0059] Four unit modules 2 are arranged in the module tube shell 1;

[0060] In this embodiment, if Figure 2 As shown, the unit modules 2 each include a substrate 4 and five independent packaging devices 5;

[0061] Five independent packaged devices 5 are mounted on the substrate 4 and are electrically connected to the mounted substrate 4 respectively;

[0062] The four unit modules 2 are electrically connected;

[0063] The module tube shell 1 is covered with an insulating protective layer (not shown in the figure), and the insulating protective layer seals the four unit modules 2 in the module tube shell 1; in this embodiment, the insulating protective layer is a protective glue.

[0064] In this embodiment, the four conductive heat dissipation components 3 are located outside the insulating protective layer and are electrically connected to the corresponding unit modules and all independent packaging components on the corresponding unit modules. In addition, the conductive heat dissipation components can also be located inside the insulating protective layer.

[0065] In this embodiment, the substrate 4 is a heat dissipation insulating base plate, one side of which is provided with a conductive circuit (not shown in the figure), and the conductive circuit is electrically connected to all packaged devices located in the same unit module. In addition, the other side of the heat dissipation insulating base plate is provided with a metal connection layer (not shown in the figure).

[0066] Furthermore, in this embodiment, a heat sink (not shown in the figure) is provided on the module tube shell 1, and the heat sink is connected to the metal connection layer to achieve heat conduction.

[0067] Specifically, in this embodiment, the heat dissipation insulation base plate is ceramic.

[0068] In this embodiment, if Figure 3 As shown, the packaged device 5 includes a carrier board, two chips 6, a conductive heat sink 7 and a plastic package 8;

[0069] The two chips 6 are inverted on the carrier board;

[0070] The conductive heat sink 7 is electrically connected to the two chips 6 and the pins 9 on the carrier board respectively;

[0071] The plastic package 8 covers the entire packaged device 5, and the upper surface of the conductive heat sink 7 and the lower surface of the carrier are exposed outside the plastic package 8. Through the device package (internal wire connection or flip-chip connection or chip stacking interconnection structure), the lead-out terminal is routed on the PCB board to achieve performance interconnection, and the interconnection structure of the chip itself is cancelled, which effectively solves the problem that if the chip itself is damaged, all the chips will be damaged. If a product fails, it can be repaired and stopped in time by removing the board and replacing the device package.

[0072] Creepage distance d = (potential difference between D and S) / (breakdown electric field strength of insulating material). By controlling the spacing between device package terminals, the creepage distance d can be effectively designed and the risk of high voltage / high current crosstalk can be avoided.

[0073] In addition, the chip is one of an IGBT power chip, a SIC power chip, a GAN power chip, and a MOSFET power chip;

[0074] When the number of chips in a single packaged device is greater than 1, the chip is a combination of one or more of an IGBT power chip, a SIC power chip, a GAN power chip, and a MOSFET power chip;

[0075] Alternatively, when the number of chips in a single packaged device is greater than 1, the chip is one or more of an IGBT power chip, a SIC power chip, a GAN power chip, and a MOSFET power chip, combined with one or more diodes. This can be set according to actual design requirements.

[0076] In this embodiment, one or more of passive components, active components and sensors are provided in the power module according to electrical function requirements.

[0077] The above-mentioned method for preparing a power module with high efficiency heat dissipation performance and including independent packaging devices comprises the following steps:

[0078] S1. In the packaged device, a first layer of connection material 10 is printed on the upper surface of the pins of the carrier board, such as Figure 4 As shown;

[0079] S2, two chips are mounted on the upper surface of the first layer of connecting material 10 by flip-flopping. Figure 5 As shown;

[0080] S3, the back of the chip is printed with a second layer of connecting material 11, such as Figure 6 As shown; the conductive heat sink is mounted on the upper surface of the second layer of connecting material 11, as Figure 7 As shown;

[0081] S4, the entire internal component is covered with a plastic package 8, and the conductive heat sink is exposed outside the plastic package, and the upper and lower double channels of heat conduction are realized, such as Figure 8 As shown;

[0082] S5, making conductive circuits on the ceramic copper-clad laminate and assembling packaging devices;

[0083] Connect the conductive heat dissipation member 3 to the conductive heat dissipation member 7 of the package device 5 to achieve the functions of electrical connection and heat dissipation;

[0084] The conductive heat dissipation member 3 is connected to the connection terminal 12 of the module tube shell 1, such as Figure 1 As shown,

[0085] Or the conductive heat dissipation component 3 is connected to the terminal 12 of the module tube shell 1, and the conductive heat dissipation component 3 leads out the electrode through the metal conductive medium 13 to achieve internal and external electrical connection, such as Fig. 9 As shown,

[0086] Or after the conductive heat dissipation component 3 is electrically connected to the packaging device 5, the electrodes formed by the conductive heat dissipation component 3 and the electrodes formed by the conductive circuit on the ceramic copper-clad board are led out by the metal conductive medium 13 to realize internal and external electrical connection;

[0087] One of the above methods for realizing internal and external electrical connection can be selected according to actual needs;

[0088] S6. Fill the module tube shell 1 with protective glue to achieve overall protection of the internal structure. The conductive heat dissipation component 3 is located inside or outside the protective glue, depending on actual heat dissipation requirements.

[0089] The working principle of this embodiment, taking NMOS+FRD as an example, provides a high level at the input end, generates current and flows in from the S pole at the connection of the tube shell, flows into the S pole of the internal chip through the S pole of the external pin terminal of the device package, and then leads the current to the D pole on the back of the chip through the internal circuit connection of the chip, and then connects with the diode through the top metal conductive medium component inside the plastic package device to form a connection between the P pole or N pole of the D diode, effectively forming a connection loop between MOS and the diode. In order to effectively lead the entire current loop to the outside of the tube shell, a metal thermal conductive material is connected above the metal conductive medium on the back of the chip, and connected to the D terminal of the tube shell, and finally the S and D terminals of the tube shell are interconnected with the exposed control circuit to form an output from the internal function of the chip to the function of the package module, and the function of double-sided heat dissipation of the chip is realized.

[0090] In addition, the chip in a single package device can also be one, such as Figures 10-12 As shown, the number of chips in a single packaged device can be arranged according to actual needs.

[0091] The preferred embodiments of the present invention have been specifically described above, but the present invention is not limited to the described embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention, and these equivalent modifications or substitutions are all within the scope defined by the claims of this application.

Claims

1. A power module with high heat dissipation performance including independent packaging devices, characterized in that: It includes a module tube shell, at least one unit module and at least one conductive heat dissipation component; At least one of the unit modules is disposed in the module shell; The unit modules each include a substrate and at least one independent packaging device; At least one independent packaged device is mounted on the substrate and is electrically connected to the mounted substrate respectively; The unit modules are electrically connected; The module shell is covered with an insulating protective layer, and the insulating protective layer seals all unit modules in the module shell; At least one conductive heat dissipation component is located inside or outside the insulating protection layer and is electrically connected to the unit module and the independent packaging device.

2. A power module with high heat dissipation performance comprising independent packaged devices as claimed in claim 1, characterized in that: The substrate is a heat dissipation insulating bottom plate, one side of which is provided with a conductive circuit, and the conductive circuit is electrically connected to all packaging devices located in the same unit module.

3. A power module with high heat dissipation performance and comprising independent packaged devices as claimed in claim 2, characterized in that: The other side of the heat dissipation insulation bottom plate is provided with a metal connection layer.

4. A power module with high heat dissipation performance and comprising independent packaged devices as claimed in claim 3, characterized in that: A heat sink is provided on the module tube shell, and the heat sink is connected to the metal connection layer to achieve heat conduction.

5. A power module with high heat dissipation performance and comprising independent packaged devices as claimed in claim 4, characterized in that: The heat dissipation insulation bottom plate is made of ceramic.

6. A power module with high heat dissipation performance and comprising independent packaged devices as claimed in claim 1, characterized in that: The insulating protective layer is protective glue.

7. A power module with high heat dissipation performance comprising independent packaged devices as claimed in claim 1, characterized in that: The packaged device comprises a carrier board, at least one chip, a conductive heat sink and a plastic package; The chip is inverted on the carrier; The conductive heat sink is electrically connected to the pins on the chip and the carrier board respectively; The plastic package body covers the entire packaged device, and the upper surface of the conductive heat sink and the lower surface of the carrier board are exposed outside the plastic package body.

8. A power module with high heat dissipation performance and comprising independent packaged devices as claimed in claim 7, characterized in that: When the number of chips in a single packaged device is 1, the chip is one of an IGBT power chip, a SIC power chip, a GAN power chip, and a MOSFET power chip.

9. A power module with high heat dissipation performance and comprising independent packaged devices as claimed in claim 7, characterized in that: When the number of chips in a single packaged device is greater than 1, the chip is a combination of one or more of an IGBT power chip, a SIC power chip, a GAN power chip, and a MOSFET power chip.

10. A power module with high heat dissipation performance and comprising independent packaged devices as claimed in claim 7, characterized in that: When the number of chips in a single packaged device is greater than 1, the chip is one or more of an IGBT power chip, a SIC power chip, a GAN power chip, a MOSFET power chip, combined with one or more diodes.

11. A power module with high heat dissipation performance comprising independent packaged devices as claimed in claim 1, characterized in that: The power module is provided with one or more of passive components, active components and sensors according to the electrical function requirements.

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