Half-bridge power module and power module
By using the design of connecting metal sheets and suspended pins in the power module, the problems of strict size requirements and poor packaging stability in the prior art are solved, higher switching speeds and output capabilities are achieved, and thermal coupling and loss.
Patent Information
- Application Number
- CN202420022433.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-04
- Publication Date
- 2024-12-17
- Estimated Expiration
- 2034-01-04
AI Technical Summary
When improving the output capacity of existing power modules, the size requirements are strict and the packaging method leads to large thermal stress and high electrical stress, resulting in low failure efficiency of the switch tube, insufficient power density, and problems such as welding risk and poor thermal performance during the packaging process.
The half-bridge power module design is adopted, and the connection between the metal sheet and the source of the switch tube is supported by connecting the metal sheet as the connection line to connect to the external device, avoiding the insulating dielectric layer on the metal plate, maximizing the power trace width and the switch tube spacing, and reducing thermal coupling and Parasitic inductors are contact-connected using silver sintering and welding processes, and the base and source are fixed by suspended pins to improve packaging stability.
It significantly improves the switching speed and output capability of the switching tube, reduces switching losses and thermal junction temperature, improves power density and long-term working reliability of the module, and avoids the problems of welding risks and poor thermal performance.
Smart Images
Figure CN222190719U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of power electronics, in particular to a half-bridge power module and a power module. Background Art
[0002] As the core part of the main circuit of various electronic devices or power systems, power modules can be directly used for processing and converting electric energy. With the development of science and technology, the size requirements of power modules are becoming more and more stringent, and power density has become one of the key indicators for comparing power modules. Improving the output capacity of power modules is one of the key means to improve the power density of power modules. Therefore, how to improve the output capacity of power modules has become the focus of people's attention. Utility Model Content
[0003] The utility model provides a half-bridge power module and a power module, the main purpose of which is to improve the output capacity of the power module.
[0004] According to one aspect of the utility model, a half-bridge power module is provided, comprising: at least one switch tube, a connecting metal sheet and a metal plate; wherein:
[0005] The drain of the power module switch tube is in contact with the first surface of the power module metal plate, and the source of the power module switch tube is in contact with the power module connecting metal sheet.
[0006] Optionally, in an embodiment of the present invention, the drain electrode of the switch tube is contact-connected with the metal plate by a silver sintering process.
[0007] Optionally, in an embodiment of the present invention, the source electrode of the switch tube is contact-connected with the connecting metal sheet by a welding process.
[0008] Optionally, in one embodiment of the present utility model, the half-bridge power module further includes a source floating pin and a base floating pin; wherein,
[0009] The connection metal sheet and the source floating pin are connected via bonding wires;
[0010] The base of the switch tube is connected to the base suspension pin via a bonding wire.
[0011] Optionally, in an embodiment of the present invention, when packaging the half-bridge power module, the base floating pins and the source floating pins are fixed by a plastic packaging material.
[0012] Optionally, in an embodiment of the present invention, there are multiple switch tubes, and all of the multiple switch tubes are in contact and connected with the connecting metal sheet.
[0013] Optionally, in one embodiment of the present invention, the metal plate is an active metal brazing substrate, and the active metal brazing substrate comprises a first copper layer, an insulating medium layer and a second copper layer; wherein,
[0014] The drain electrode of the switch tube is in contact with the first surface of the first copper layer;
[0015] The second surface of the first copper layer is in contact with the first surface of the insulating dielectric layer;
[0016] The second surface of the insulating medium layer is in contact with the first surface of the second copper layer.
[0017] Optionally, in one embodiment of the present utility model, the half-bridge power module further includes a heat sink; wherein,
[0018] The heat sink is contacted and connected to the second surface of the second copper layer through a welding process.
[0019] According to another aspect of the present invention, a power module is provided, comprising: an upper half-bridge power module and a lower half-bridge power module, wherein the upper half-bridge power module and the lower half-bridge power module both adopt any of the half-bridge power modules shown in the aforementioned aspect.
[0020] Optionally, in one embodiment of the present invention, the metal plate includes an AC region, a DC positive region and a DC negative region; wherein,
[0021] The drain of the first switch tube is in contact with the DC positive electrode region, wherein the first switch tube is a switch tube in the upper half-bridge power module;
[0022] The drain of the second switch tube and the first connecting metal sheet are respectively in contact with and connected to the AC region, wherein the second switch tube is a switch tube in the lower half-bridge power module, and the first connecting metal sheet is a connecting metal sheet in the upper half-bridge power module;
[0023] The second connecting metal sheet is in contact with the DC negative electrode region, wherein the second connecting metal sheet is a connecting metal sheet in the lower half-bridge power module.
[0024] In summary, in one or more embodiments of the utility model, a connecting metal sheet is provided as a connecting line to support the connection between the source of the switching tube and the external device. There is no need to provide another insulating medium layer above the first surface of the metal plate to make a connecting line between the source of the switching tube and the external device. All the space in the first surface of the metal plate can be used for power connection, which can maximize the power line width, maximize the spacing between different switching tubes, significantly reduce the thermal coupling between different switching tubes, reduce the overall parasitic inductance and the overall junction temperature, improve the switching speed of the switching tube, reduce the switching loss, and further improve the output capacity of the half-bridge power module.
[0025] Additional aspects and advantages of the present invention will be given in part in the following description and in part will become apparent from the following description or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:
[0027] Figure 1 A top view of a half-bridge power module provided by an embodiment of the utility model;
[0028] Figure 2 An equivalent circuit diagram of a half-bridge power module provided by an embodiment of the utility model;
[0029] Figure 3 A cross-sectional view of a half-bridge power module provided by an embodiment of the utility model;
[0030] Figure 4 A top view of a power module provided by an embodiment of the utility model.
[0031] Explanation of reference numerals: switch tube 11; connecting metal sheet 12; metal plate 13; source floating pin s; base floating pin g; first copper layer 31; insulating dielectric layer 32; second copper layer 33; AC region AC; DC positive region DC+; DC negative region DC-. DETAILED DESCRIPTION
[0032] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. On the contrary, the embodiments of the present invention include all changes, modifications and equivalents that fall within the spirit and connotation of the appended claims.
[0033] It should be noted that new energy vehicles have an increasing demand for high-power applications of motor controllers, and at the same time, the requirements for the size of the power system are becoming more and more stringent. Power density has become one of the key indicators for comparing motor controllers. At present, the key components of motor controllers, switches and film capacitors, occupy a large part of the physical space. Film capacitors are limited by the thickness of the film material and are difficult to improve too much. Therefore, improving the output capacity of the switch tube is one of the key means to improve the power density of the motor controller.
[0034] In the related technology, the switch tube is integrated on the active metal brazing (AMB) substrate to form a power module. The power module packaging will lead to poor current distribution of the switch tube. The uneven current will cause the worst switch tube to have greater thermal stress and electrical stress than other switch tubes, and the worst switch tube temperature will rise and the failure rate will be high, thereby limiting the outflow capacity of the entire power module and indirectly leading to an increase in the cost of the power module. Secondly, the power module packaging will also lead to inconsistent chip driving, and circulating current will be generated between different chip drivers, resulting in serious oscillation.
[0035] In addition, the power density of the power module can be improved by welding a layer of insulating medium on the top of the AMB substrate. However, when the system is welded to the heat sink at the bottom of the AMB substrate, there is a risk of secondary melting of the solder between the top of the AMB substrate and the insulating medium; and when the layout connection is made, the signal pin is led out from the middle of the plastic package and welded to the AMB substrate for the second time, which makes the signal pin have a stress risk when connected to the AMB substrate, and it is easy to fall off. The risk of signal connection failure is higher than that of the signal pin being directly welded to the AMB substrate; secondly, the newly added insulating medium will also occupy the power routing space, which will reduce the spacing between the switch tubes and deteriorate the thermal performance.
[0036] The utility model is described in detail below in conjunction with specific embodiments.
[0037] Figure 1 A top view of a half-bridge power module provided by an embodiment of the utility model.
[0038] like Figure 1 As shown, the half-bridge power module includes: at least one switch tube 11, a connecting metal sheet 12 and a metal plate 13; wherein,
[0039] The drain of the switch tube 11 is in contact with the first surface of the metal plate 13 , and the source of the switch tube 11 is in contact with the connecting metal sheet 12 .
[0040] According to some embodiments, the switch tube 11 refers to a device that functions as a switch. The switch tube 11 includes but is not limited to a bipolar junction transistor (BJT), a gate turn-off thyristor (GTO), an insulated gate bipolar transistor (IGBT), an integrated gate commutated thyristor (IGCT), and a metal-oxide-semiconductor field-effect transistor (MOSFET, MOS).
[0041] In some embodiments, the switch tube 11 may be, for example, a SiC MOSFET chip.
[0042] According to some embodiments, the connecting metal sheet 12 serves as a conductive device to support the connection between the source of the switch tube 11 and an external device. Therefore, there is no need to set another insulating medium layer above the first surface of the metal plate 13 to make a connecting line between the source of the switch tube 11 and the external device. All the space in the first surface of the metal plate 13 can be used for power connection, which can maximize the power line width, maximize the spacing between different switch tubes, significantly reduce the thermal coupling between different switch tubes, reduce the overall parasitic inductance and the overall junction temperature, improve the switching speed of the switch tube, reduce the switching loss, and further improve the output capacity of the half-bridge power module.
[0043] Optional, such as Figure 1 As shown, the half-bridge power module further includes a source floating pin s and a base floating pin g; wherein,
[0044] The connection metal sheet 12 and the source suspended pin s are connected via a bonding wire;
[0045] The base of the switch tube 11 is connected to the base floating pin g via a bonding wire.
[0046] According to some embodiments, both the base floating pin g and the source floating pin s are used to support the connection between the half-bridge power module and external devices.
[0047] In some embodiments, the floating pin refers to a pin that is separated from the metal plate and connected to the metal plate through a bonding wire. Compared with the signal pin that is led out from the middle of the plastic package and is secondary-welded to the AMB substrate, the floating pin does not have stress risk.
[0048] Optionally, when packaging the half-bridge power module, the base floating pin g and the source floating pin s are fixed by a plastic packaging material.
[0049] According to some embodiments, when the base floating pin g and the source floating pin s are fixed by the plastic packaging material, their specific fixing positions are not limited. For example, they can be fixed around the metal plate 13 .
[0050] Optionally, there are multiple switch tubes 11 , and all of the multiple switch tubes 11 are in contact and connected with the connecting metal sheet 12 .
[0051] It should be noted that Figure 2 The equivalent circuit diagram of a half-bridge power module provided by the embodiment of the utility model is shown in FIG. Figure 1 and 2 As shown in the figure, when the half-bridge power module includes 6 switch tubes, namely chip1, chip2, chip3, chip4, chip5, and chip6, the driving source connection method will cause a potential difference between the sources of chip1 and chip4, chip2 and chip5, and chip3 and chip6 due to the turn-on and turn-off process di / dt, making the actual driving gate voltage of chip4, chip5, and chip6 lower than that of chip1, chip2, and chip3, causing the switching speed of chip4, chip5, and chip6 to be slower than that of chip1, chip2, and chip3. , which increases the switch stress of chip1, chip2, and chip3. By interconnecting the sources of clip1 to chip6 through connecting metal sheets, the Kelvin equivalent effect can be achieved, the source potential difference between different switch tubes can be reduced, the uneven current problem caused by the drive connection of this solution can be solved, the current balance of the half-bridge power module can be improved, the temperature of the worst switch tube can be reduced, the temperature between the switch tubes can be balanced, and the output capacity and long-term working reliability of the half-bridge power module can be improved; secondly, the circulating current influence between the drivers can be reduced, the mutual interference and failure risk of the drivers can be reduced, and the long-term working reliability of the half-bridge power module can be improved.
[0052] Optional, Figure 3 This is a cross-sectional view of a half-bridge power module provided by an embodiment of the utility model. Figure 3 As shown, the metal plate is an active metal brazing (AMB) substrate, and the active metal brazing substrate includes a first copper layer 31, an insulating medium layer 32 and a second copper layer 33; wherein,
[0053] The drain electrode of the switch tube 11 is in contact with the first surface of the first copper layer 31;
[0054] The second surface of the first copper layer 31 is in contact with the first surface of the insulating dielectric layer 32;
[0055] The second surface of the insulating dielectric layer 32 is in contact with the first surface of the second copper layer 33 .
[0056] According to some embodiments, the insulating dielectric layer 32 may be made of Si 3 N 4 material, for example.
[0057] According to some embodiments, the drain electrode of the switch tube 11 is contact-connected with the metal plate 13 by a silver sintering process. Figure 3 As shown, the drain electrode of the switch tube 11 is connected to the first surface of the first copper layer 31 by a solder used in a silver sintering process.
[0058] In some embodiments, the silver sintering process is a process of heating powdered silver to a molten state and forming an adhesive layer on the surface of other materials. The drain of the switch tube 11 and the metal plate 13 are contacted and connected through the silver sintering process, which can improve the connection effect between the drain of the switch tube and the metal plate.
[0059] According to some embodiments, the source electrode of the switch tube 11 is contact-connected with the connecting metal sheet 12 by a welding process.
[0060] In some embodiments, the welding process refers to a manufacturing process of joining metal or other thermoplastic materials such as plastic by heating, high temperature or high pressure. The source electrode of the switch tube and the connecting metal sheet are contacted and connected by the welding process, which can improve the connection effect between the source electrode of the switch tube 11 and the connecting metal sheet 12.
[0061] Optionally, the half-bridge power module further includes a heat sink; wherein,
[0062] The heat sink is contacted and connected to the second surface of the second copper layer 33 by a welding process.
[0063] According to some embodiments, Figure 3 As shown, the heat sink and the second surface of the second copper layer 33 may be connected by solder used in a welding process.
[0064] In some embodiments, the heat sink is used to dissipate heat for the half-bridge power module when the half-bridge power module enters a working state.
[0065] In summary, the half-bridge power module provided by the embodiment of the utility model supports the connection between the source of the switching tube and the external device by setting a connecting metal sheet as a connecting line. There is no need to set an insulating medium layer above the first surface of the metal plate to make a connecting line between the source of the switching tube and the external device. All the space in the first surface of the metal plate can be used for power connection, which can maximize the power routing width, maximize the spacing between different switching tubes, significantly reduce the thermal coupling between different switching tubes, reduce the overall parasitic inductance and the overall junction temperature, improve the switching speed of the switching tube, reduce the switching loss, and further improve the output capacity of the half-bridge power module.
[0066] The embodiment of the utility model also provides a power module.
[0067] Specifically, the half-bridge power module includes: an upper half-bridge power module and a lower half-bridge power module, and both the upper half-bridge power module and the lower half-bridge power module are half-bridge power modules shown in any of the above embodiments.
[0068] Optional, Figure 4 A top view of a power module provided by an embodiment of the utility model. Figure 4 As shown, the metal plate includes an AC region AC, a DC positive region DC+ and a DC negative region DC-; wherein,
[0069] The drain of the first switch tube is in contact with the DC positive region DC+, wherein the first switch tube is a switch tube in the upper half-bridge power module, such as Figure 4 As shown in chip7, chip8, chip9, chip10, chip11, and chip12;
[0070] The drain of the second switch tube and the first connecting metal sheet are respectively connected to the AC region AC, wherein the second switch tube is a switch tube in the lower half-bridge power module, such as Figure 4 As shown in chip1, chip2, chip3, chip4, chip5, and chip6; the first connecting metal sheet is a connecting metal sheet in the upper half-bridge power module;
[0071] The second connecting metal sheet is in contact with the DC negative region DC-, wherein the second connecting metal sheet is a connecting metal sheet in the lower half-bridge power module.
[0072] In summary, the power module provided by the embodiment of the utility model supports the connection between the half-bridge power module and the external device by setting a connecting metal sheet as a connecting line. There is no need to set an insulating medium layer above the first surface of the metal plate to make a connecting line when connecting the half-bridge power module and the external device. All the space in the first surface of the metal plate can be used for power connection, which can maximize the power routing width, maximize the spacing between different switching tubes, significantly reduce the thermal coupling between different switching tubes, reduce the overall parasitic inductance and the overall junction temperature, improve the switching speed of the switching tube, reduce the switching loss, and further improve the output capacity of the half-bridge power module.
[0073] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms may be for different embodiments or examples. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.
[0074] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.
[0075] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.
Claims
1. A half-bridge power module, characterized in that: include: At least one switch tube, a connecting metal sheet and a metal plate; wherein, The drain of the switch tube is in contact with the first surface of the metal plate, and the source of the switch tube is in contact with the connecting metal sheet.
2. The half-bridge power module according to claim 1, characterized in that: The drain electrode of the switch tube is contact-connected with the metal plate through a silver sintering process.
3. The half-bridge power module according to claim 1, characterized in that: The source electrode of the switch tube is contact-connected with the connecting metal sheet by welding.
4. The half-bridge power module according to claim 1, characterized in that: The half-bridge power module also includes a source floating pin and a base floating pin; wherein, The connecting metal sheet and the source floating pin are connected via a bonding wire; The base of the switch tube is connected to the base suspension pin via a bonding wire.
5. The half-bridge power module according to claim 4, characterized in that: When the half-bridge power module is packaged, the base floating pins and the source floating pins are fixed by a plastic packaging material.
6. The half-bridge power module according to claim 1, characterized in that: There are multiple switch tubes, and all of the multiple switch tubes are in contact with and connected to the connecting metal sheet.
7. The half-bridge power module according to claim 1, characterized in that: The metal plate is an active metal brazing substrate, and the active metal brazing substrate comprises a first copper layer, an insulating medium layer, and a second copper layer; wherein, The drain electrode of the switch tube is in contact with the first surface of the first copper layer; The second surface of the first copper layer is in contact with the first surface of the insulating dielectric layer; The second surface of the insulating medium layer is in contact with the first surface of the second copper layer.
8. The half-bridge power module according to claim 7, characterized in that: The half-bridge power module also includes a heat sink; wherein, The heat sink is contacted and connected to the second surface of the second copper layer through a welding process.
9. A power module, characterized in that: include: An upper half-bridge power module and a lower half-bridge power module, wherein both the upper half-bridge power module and the lower half-bridge power module are half-bridge power modules as claimed in any one of claims 1 to 8.
10. The power module according to claim 9, characterized in that: The metal plate includes an AC region, a DC positive region and a DC negative region; wherein, The drain of the first switch tube is in contact with the DC positive electrode region, wherein the first switch tube is a switch tube in the upper half-bridge power module; The drain of the second switch tube and the first connecting metal sheet are respectively in contact with and connected to the AC region, wherein the second switch tube is a switch tube in the lower half-bridge power module, and the first connecting metal sheet is a connecting metal sheet in the upper half-bridge power module; The second connecting metal sheet is in contact with the DC negative electrode region, wherein the second connecting metal sheet is a connecting metal sheet in the lower half-bridge power module.