Hybrid power module
The integration of silicon carbide IGBTs and MOSFETs or IGBTs with diodes in power modules addresses design challenges, enhancing performance by optimizing current flow and reducing losses, achieving higher voltages and currents with a smaller footprint.
Patent Information
- Application Number
- JP2025180154
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2019-07-08
- Filing Date
- 2025-10-27
- Publication Date
- 2026-02-12
AI Technical Summary
Existing power modules incorporating silicon carbide power semiconductor devices face design challenges that require new manufacturing methods to maintain high efficiency, a small footprint, and low cost while handling high voltages and currents.
A power module design that includes silicon carbide insulated gate bipolar transistors (IGBTs) and metal oxide semiconductor field effect transistors (MOSFETs) coupled in parallel, or silicon carbide IGBTs and diodes in anti-parallel configurations, to improve performance by optimizing forward and reverse conduction currents and reducing switching losses.
The design achieves higher blocking voltages, forward and reverse conduction currents, and reduced switching losses compared to conventional modules, with improved efficiency and cost-effectiveness.
Smart Images
Figure 2026022654000001_ABST
Abstract
Description
[Technical Field]
[0001] Government support
[0001] This invention was made with government funds under Contract No. N00014-10-D-0145 awarded by the Department of Defense. The United States Government has certain rights in this invention.
[0002] This disclosure relates to power modules, and more particularly to power modules that include one or more silicon carbide power semiconductor devices. [Background technology]
[0003]
[0003] Power modules are used to selectively deliver power to or from a load. The primary functionality of a power module is provided by several power semiconductor devices (e.g., transistors, diodes, etc.) within the power module. These power semiconductor devices are provided as one or more semiconductor dies mounted on a power substrate. When provided in a power system with one or more other power modules and / or one or more other components, the power semiconductor devices of a power module may form part of a power converter, such as a half-bridge converter, a full-bridge converter, a buck converter, or a boost converter. Because power systems often handle high voltages and currents, the power semiconductor devices of a power module must likewise be able to reliably switch said high voltages and currents. In recent years, reducing power consumption has become a major concern in power applications, and it is therefore desirable for power modules to provide low losses and therefore high efficiency. As always, doing so at low cost is desirable.
[0004]
[0004] Typically, one or more power semiconductor devices in a power module form at least one switch position. A typical power module configuration allows current to flow in both the forward direction (first quadrant conduction) and the reverse direction (third quadrant conduction) through at least one switch position. Traditionally, power semiconductor devices in power modules have been silicon devices due to well-known processes for manufacturing silicon power semiconductor devices, which can reliably switch high voltages and currents. However, in recent years, silicon carbide power semiconductor devices have become popular due to the significant improvements in switching speed and efficiency they offer. While power modules incorporating silicon carbide power semiconductor devices offer several performance advantages over power modules incorporating corresponding silicon power semiconductor devices, their use in power modules presents several design challenges, such that the design principles applied to power modules incorporating silicon power semiconductor devices do not apply equally to power modules incorporating silicon carbide power semiconductor devices. In short, including silicon carbide power semiconductor devices in a power module is not a matter of simply replacing the corresponding silicon power semiconductor devices in an existing power module. Summary of the Invention [Problem to be solved by the invention]
[0005] In light of the above, there is a need to develop a method for manufacturing a semiconductor device that maintains high efficiency, a small footprint, and low cost. There is currently a need for power modules containing silicon carbide power semiconductor devices that can handle high voltages and currents while maintaining a high power rating. [Means for solving the problem]
[0006] In one embodiment, a power module includes a plurality of power semiconductor devices. The plurality of power semiconductor devices includes an insulated gate bipolar transistor (IGBT) and a metal oxide semiconductor field effect transistor (MOSFET) coupled in parallel between a first power switching terminal and a second power switching terminal. The IGBT and the MOSFET are silicon carbide semiconductor devices. By providing the IGBT and the MOSFET together, the tradeoff between the forward conduction current and the reverse conduction current of the power module, the efficiency, and the specific current rating of the power module can be improved. Furthermore, providing the IGBT and the MOSFET as silicon carbide devices can significantly improve the performance of the power module.
[0007] In one embodiment, a power module includes a plurality of power semiconductor devices. The plurality of power semiconductor devices includes an IGBT and a diode. The IGBT and the diode are coupled in anti-parallel between a first power switching terminal and a second power switching terminal. The IGBT and the diode are silicon carbide semiconductor devices. By providing the IGBT and the diode as silicon carbide semiconductor devices, performance of the power module can be significantly improved.
[0008] In one embodiment, the power module includes a plurality of power semiconductor dies. The plurality of power semiconductor dies is configured such that the power module:
[0009]
number
[0010] The first power switch is configured to provide a specific current rating greater than and a second power switching terminal, where V b(r)is the rated blocking voltage of the power module. The specific rated current is for the active area of the power semiconductor die, not including edge terminations and non-active structures.
[0011] In one embodiment, a method of operating a power module including parallel-coupled silicon carbide IGBTs and silicon carbide MOSFETs includes switching the power module from a forward conduction mode to a blocking mode by placing the IGBTs in a blocking mode before placing the MOSFETs in a blocking mode, and switching the power module from a blocking mode to a forward conduction mode by placing at least one MOSFET in a reverse conduction mode before placing at least one IGBT in a forward conduction mode. By operating the power module in this manner, switching losses in the power module can be significantly reduced.
[0012] Those skilled in the art will appreciate the scope of the present disclosure and realize additional aspects thereof after reading the following detailed description of the preferred embodiments in conjunction with the accompanying drawings.
[0011] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate several aspects of the present disclosure and, together with the description, serve to explain the principles of the disclosure. [Brief explanation of the drawings]
[0013] [Figure 1] FIG. 1 illustrates a power module according to one embodiment of the present disclosure. [Figure 2A] FIG. 1 is a functional schematic diagram illustrating switch positions of a power module according to one embodiment of the present disclosure. [Figure 2B]
[0014] FIG. 2 illustrates an exemplary arrangement of switch positions for a power module according to one embodiment of the present disclosure. [Figure 2C] FIG. 2 illustrates an exemplary arrangement of switch positions for a power module according to one embodiment of the present disclosure. [Figure 3]
[0015] 1 is a graph illustrating the relationship between forward conduction current and reverse conduction current of a power module according to one embodiment of the present disclosure. [Figure 4]
[0016] FIG. 2 is a functional schematic diagram illustrating switch positions of a power module according to one embodiment of the present disclosure. [Figure 5]
[0017] 1 is a graph illustrating the relationship between forward conduction current and reverse conduction current of a power module according to one embodiment of the present disclosure. [Figure 6]
[0018] 1 is a graph illustrating power output of a power module according to various embodiments of the present disclosure. [Figure 7]
[0019] FIG. 1 is a flow diagram illustrating a method of operating a power module according to one embodiment of the present disclosure. [Figure 8]
[0020] FIG. 2 is a functional schematic diagram illustrating switch positions of a power module according to one embodiment of the present disclosure. [Figure 9]
[0021] 1 is a graph illustrating normalized output power versus normalized power loss for several power modules according to various embodiments of the present disclosure. [Figure 10]
[0022] 1 is a graph illustrating the relationship between specific current rating and voltage rating of a power module according to one embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION
[0014]
[0023] The embodiments described below represent the information necessary to enable those skilled in the art to practice the embodiments and illustrate the best modes of practicing the embodiments. Upon reading the following description in light of the accompanying drawings, those skilled in the art will understand the concepts of the present disclosure and will recognize applications of these concepts not specifically addressed herein. It is understood that these concepts and applications are encompassed within the scope of this disclosure and the accompanying claims.
[0015]
[0024] As used herein, terms such as first, second, etc. may be used to describe various elements, but it will be understood that these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, a first element could be referred to as a second element, and similarly, a second element could be referred to as the first element, without departing from the scope of the present disclosure. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.
[0016]
[0025] When an element, such as a layer, region, or substrate, is referred to as being "on" or extending "on" another element, it will be understood that it can be directly on or extending directly onto the other elements, or that intervening elements may also be present. In contrast, when an element is referred to as being "directly on" or extending "directly onto" another element, there are no intervening elements. Similarly, when an element, such as a layer, region, or substrate, is referred to as being "above" or extending "upon" another element, it will be understood that it can be directly on or extending directly onto the other elements, or that intervening elements may also be present. In contrast, when an element is referred to as being "directly on" or extending "directly onto" another element, there are no intervening elements. When an element is referred to as being "connected" or "coupled" to another element, it will be understood that it can be directly connected or coupled to the other elements, or that intervening elements may also be present. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, there are no intervening elements present.
[0017]
[0026] Relative terms such as "lower" or "upper" or "top" or "lower" or "horizontal" or "vertical" are used herein to refer to the relative position of an element, layer, or The terms "layer" and "region" may be used to describe the relationship of one element, layer, or region to another element, layer, or region. It will be understood that these terms, and those discussed above, are intended to encompass different orientations of the device in addition to the orientation depicted in the figures.
[0018]
[0027] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. It will be further understood that as used herein, the terms "comprises," "comprising," "including," and / or "comprising" specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.
[0019]
[0028] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Terms used herein should be interpreted to have a meaning consistent with their meaning in the context of the present specification and related art, and are not to be interpreted in an idealized or overly formal sense unless expressly defined as such herein.
[0020]
[0029] FIG. 1 illustrates a power module 10 according to one embodiment of the present disclosure. The power module 10 includes a housing 12, a power substrate 14 within the housing 12, and several power semiconductor dies 16 on the power substrate 14. Although not shown, the housing 12 may cover the power substrate 14 such that the power substrate 14 is partially or completely enclosed by the housing 12. Additionally, several signal paths formed by traces on the power substrate 14, wire bonds, and contact terminals, may connect the power semiconductor dies 16 to each other to form a desired topology of the power module 10, as described below. Finally, the power substrate 14 may be provided on a base plate exposed through the bottom of the housing 12. While twelve power semiconductor dies 16 are shown in FIG. 1, any number of power semiconductor dies 16 may be provided in the power module 10 without departing from the principles of the present disclosure. However, as described below, the footprint of the power module 10 is generally limited by standards and practicality, and therefore the total number of power semiconductor dies 16 that can be provided in the power module 10 may be limited. In various embodiments, power module 10 may include four power semiconductor dies 16, eight power semiconductor dies 16, or any other number of power semiconductor dies 16.
[0021]
[0030] 2A is a functional schematic diagram illustrating a switch position SW in a power module 10 according to one embodiment of the present disclosure. The switch position SW may include all or a portion of a power semiconductor die 16, which may be coupled together to form several power semiconductor devices, as shown. In particular, the power semiconductor die 16 may be coupled together to provide an insulated gate bipolar transistor (IGBT) 18 coupled anti-parallel with a diode 20. The IGBT 18 includes a base contact (B) coupled to a control terminal 22, a collector contact (C) coupled to a first power switching terminal 24, and an emitter contact (E) coupled to a second power switching terminal 26. The diode 20 includes an anode coupled to the second power switching terminal 26 and a cathode coupled to the first power switching terminal 24.
[0022]
[0031] The IGBT 18 may be provided by several power semiconductor dies 16 coupled in parallel, each being an IGBT semiconductor die. Similarly, the diode 20 may be provided by several power semiconductor dies 16 coupled in parallel, each being a diode semiconductor die. The number of semiconductor dies 16 used for the IGBTs 18 may differ from the number of semiconductor dies 16 used for the diodes 20 (e.g., depending on the current capacity of each device). Each of the power semiconductor dies 16 may be rated for a particular blocking voltage and a particular forward conduction current. Providing multiple power semiconductor dies 16 for each of the IGBTs 18 and diodes 20 increases its forward conduction current (by an integer multiple for each additional power semiconductor die 16). Thus, switch position SW may be able to block high voltages and conduct high currents both in the forward direction through the IGBTs 18 (from the first power switching terminal 24 to the second power switching terminal 26) and in the reverse direction through the diodes 20 (from the second power switching terminal 26 to the first power switching terminal 24).
[0023]
[0032] In some embodiments, power module 10 may include multiple switch positions SW. The switch positions SW may be coupled together in series or parallel between first power switching terminal 24 and second power switching terminal 26, depending on the application of power module 10. In some embodiments, the switch positions SW may never be coupled together. For example, FIG. 2B shows two switch positions SW coupled in series, which may be used to form the switching portion of a half-bridge power converter. FIG. 2C shows four switch positions SW, where two pairs of the four switch positions SW are coupled in series. Two pairs of the series-coupled switch positions SW may be coupled in parallel to form the switching portion of a full-bridge power converter, or may be left uncoupled. In particular, power module 10 may provide any number of switch positions SW configured in any desired manner.
[0024]
[0033] In one embodiment, IGBTs 18 and diodes 20 are silicon carbide semiconductor devices. Providing IGBTs 18 and diodes 20 as silicon carbide devices may provide power module 10 with several performance advantages, such as increased blocking voltage, forward conduction current, and reverse conduction current, as well as reduced switching and conduction losses, compared to conventional power modules of the same size. For example, power module 10 may be able to block a voltage of greater than 1 kV between first power switching terminal 24 and second power switching terminal 26 in a blocking mode of operation. In various embodiments, power module 10 may be capable of blocking voltages greater than 2 kV, greater than 3 kV, greater than 4 kV, greater than 5 kV, greater than 6 kV, greater than 7 kV, greater than 8 kV, greater than 9 kV, greater than 10 kV, greater than 11 kV, greater than 12 kV, greater than 13 kV, greater than 14 kV, greater than 15 kV, greater than 16 kV, greater than 17 kV, greater than 18 kV, greater than 19 kV, greater than 20 kV, greater than 21 kV, greater than 22 kV, greater than 23 kV, greater than 24 kV, greater than 25 kV, and up to 26 kV. The blocking voltage of power module 10 may further be expressed as a range beginning and ending at any of the above blocking voltages. For example, power module 10 may be able to block voltages between 2 kV and 26 kV, between 10 kV and 26 kV, between 20 kV and 26 kV, between 2 kV and 12 kV, between 10 kV and 15 kV, between 11 kV and 26 kV, etc. For the above blocking voltages, the forward conduction current (between first power switching terminal 24 and second power switching terminal 26) and the reverse conduction current (between second power switching terminal 26 and first power switching terminal 24) depend on the semiconductor die area and therefore the number of power semiconductor dies 16 dedicated to each of IGBTs 18 and diodes 20, respectively.
[0025]
[0034] 3 is a graph illustrating the forward conduction current and reverse conduction current of the power module 10 based on the number of power semiconductor dies 16 used in the IGBTs 18 versus the number of power semiconductor dies 16 used in the diodes 20. As shown, the maximum reverse conduction current is , occurs when all 12 of the power semiconductor dies 16 are used for the diodes 20. However, the power module 10 cannot provide forward conduction current in this scenario. As the number of power semiconductor dies 16 used for the IGBTs 18 increases, the forward conduction current of the power module 10 similarly increases, and the reverse conduction current of the power module 10 decreases. The power module 10 is capable of blocking the voltages discussed above in any of the scenarios illustrated in FIG. 3 , and thus is capable of both forward and reverse conduction currents greater than 200 A, as well as other illustrated scenarios. In various embodiments, the power module can provide forward and reverse conduction currents in the ranges of 100 A to 6 kA, 150 A to 6 kA, 200 A to 6 kA, 250 A to 6 kA, 300 A to 6 kA, 500 A to 6 kA, 1 kA to 6000 kA, and any subrange formed by any of the above ranges. In the exemplary situation illustrated by the graph of FIG. 3, when three of the twelve power semiconductor dies 16 are used for IGBTs 18 and the remaining nine of the twelve power semiconductor dies 16 are used for diodes 20, the forward conduction current and reverse conduction current of the power module 10 are relatively equal.
[0026]
[0035] As discussed above, the footprint of power module 10 is limited by both standards and practicality. For the same footprint, power module 10 can achieve a much higher blocking voltage at the forward and reverse conduction currents described above than a power module in which the power semiconductor devices are silicon.
[0027]
[0036] As illustrated above, a trade-off exists between the forward conduction current and the reverse conduction current of the power module 10. Because the footprint of the power module 10 is limited, the achievable forward and reverse conduction current of the power module 10 is similarly limited by the space available for the power semiconductor dies 16. This is because the amount of current the IGBTs 18 can pass (forward conduction current) is a function of the area of the semiconductor die dedicated to the IGBTs 18, and similarly, the amount of current the diodes 20 can pass (reverse conduction current) is a function of the area of the semiconductor die dedicated to the diodes 20. In some embodiments, the diodes 20 may be junction barrier Schottky (JBS) diodes. Thus, for a given area of the semiconductor die, the diodes 20 can conduct much less current than the IGBTs 18, thereby requiring much more semiconductor die area (and therefore the number of power semiconductor dies 16) dedicated to the diodes 20 than to the IGBTs 18 to achieve a desired reverse conduction current. The total number of power semiconductor dies 16 is limited by the footprint of power module 10, which also limits the forward conduction current and reverse conduction current of power module 10. While the above-described power module 10 can achieve higher blocking voltages, forward conduction currents, and reverse conduction currents than previously achievable, it is always desirable to further increase the forward conduction current and reverse conduction current of power module 10.
[0028]
[0037] 4 is a functional schematic diagram illustrating a switch position SW in a power module 10 according to an additional embodiment of the present disclosure. The switch position SW may include all or a portion of a power semiconductor die 16, which may be coupled together to form several power semiconductor devices, as shown. In particular, the power semiconductor die 16 may be coupled together to provide an IGBT 28 and a metal-oxide-semiconductor field-effect transistor (MOSFET) 30. The IGBT 28 includes a gate contact (G) coupled to a first control terminal 32, a collector contact (C) coupled to a first power switching terminal 34, and an emitter contact (E) coupled to a second power switching terminal 36. The MOSFET 30 includes a gate contact (G) coupled to a second control terminal 38, a drain contact (D) coupled to the first power switching terminal 34, and a source contact (S) coupled to the second power switching terminal 36.
[0029]
[0038] The IGBT 28 may be provided by several power semiconductor dies 16 coupled in parallel, each being an IGBT semiconductor die. Similarly, the MOSFET 30 may be provided by several power semiconductor dies 16 coupled in parallel, each being a MOSFET semiconductor die. In one embodiment, one or more of the semiconductor dies 16 are either discrete (i.e., not electrically coupled to the die itself) or integrated with each other in any desired manner to provide both IGBT and MOSFET devices on the same die. Each of the power semiconductor dies 16 may be rated for a specific blocking voltage and a specific forward conduction current. Providing multiple power semiconductor dies for each of the IGBT 28 and the MOSFET 30 increases that forward conduction current (by an integer multiple for each additional power semiconductor die 16). Thus, the switch position SW may be able to block high voltages and conduct high currents in both the forward direction (from the first power switching terminal 34 to the second power switching terminal 36) and the reverse direction (from the second power switching terminal 36 to the first power switching terminal 34).
[0030]
[0039] As discussed above, in some embodiments, power module 10 may include multiple switch positions SW. The switch positions SW may be coupled in series or parallel between first power switching terminal 34 and second power switching terminal 36 depending on the application of power module 10. In some embodiments, the switch positions SW may never be coupled together.
[0031]
[0040] In one embodiment, the IGBTs 28 and the MOSFETs 30 are silicon carbide semiconductor devices. Providing the IGBTs 28 and the MOSFETs 30 as silicon carbide devices may provide the power module 10 with several performance advantages, such as increased blocking voltage, forward conduction current, and reverse conduction current, and reduced switching and conduction losses, compared to conventional power modules. For example, the power module 10 may be able to block voltages greater than 1 kV between the first power switching terminal 34 and the second power switching terminal 36. In various embodiments, power module 10 may be capable of blocking voltages greater than 2 kV, greater than 3 kV, greater than 4 kV, greater than 5 kV, greater than 6 kV, greater than 7 kV, greater than 8 kV, greater than 9 kV, greater than 10 kV, greater than 11 kV, greater than 12 kV, greater than 13 kV, greater than 14 kV, greater than 15 kV, greater than 16 kV, greater than 17 kV, greater than 18 kV, greater than 19 kV, greater than 20 kV, greater than 21 kV, greater than 22 kV, greater than 23 kV, greater than 24 kV, greater than 25 kV, and up to 26 kV. The blocking voltage of power module 10 may further be expressed as a range beginning and ending at any of the above blocking voltages. For example, power module 10 may be capable of blocking voltages between 2 kV and 26 kV, between 10 kV and 26 kV, between 20 kV and 26 kV, between 2 kV and 12 kV, between 10 kV and 15 kV, between 11 kV and 26 kV, etc. For the above blocking voltages, the forward conduction current (between first power switching terminal 34 and second power switching terminal 36) and the reverse conduction current (between second power switching terminal 36 and first power switching terminal 34) depend on the semiconductor die area and, therefore, the number of power semiconductor dies 16 dedicated to each of IGBTs 28 and MOSFETs 30.
[0032]
[0041] 5 is a graph showing the forward conduction current and reverse conduction current of power module 10 based on the number of power semiconductor dies 16 used for IGBTs 28 versus the number of power semiconductor dies 16 used for MOSFETs 30. In the exemplary situation illustrated in the graph in FIG. 5, the maximum reverse conduction current occurs when all 12 of the power semiconductor dies 16 are used for MOSFETs 30. In this scenario, power module 10 While forward conduction current is still possible, the tradeoff between reverse conduction current and forward conduction current is improved by introducing one or more IGBTs. As the number of power semiconductor dies 16 used for IGBTs 28 increases, the forward conduction current of the power module 10 similarly increases, while the reverse conduction current of the power module 10 decreases. The power module 10 is capable of blocking the voltages discussed above in any of the scenarios illustrated in FIG. 3 , and thus is capable of forward and reverse conduction currents greater than 250 A, as well as other illustrated scenarios. In various embodiments, the power module can provide forward and reverse conduction currents in the ranges of 100 A to 6 kA, 150 A to 6 kA, 200 A to 6 kA, 250 A to 6 kA, 300 A to 6 kA, 500 A to 6 kA, 1 kA to 6 kA, and any subrange formed by any of the above ranges. When three of the twelve power semiconductor dies 16 are used for IGBTs 28 and the remaining nine of the twelve power semiconductor dies 16 are used for MOSFETs 30, the forward conduction current and reverse conduction current of the power module 10 are relatively equal.
[0033]
[0042] As discussed above, the footprint of the power module 10 is limited. For the same footprint, the power module 10 can achieve a much higher blocking voltage at the forward and reverse conduction currents described above than a power module in which the devices are silicon. Furthermore, the power module 10 discussed with reference to Figures 4 and 5 can achieve a higher forward conduction current for the same reverse conduction current than the power module 10 discussed with reference to Figures 2 and 3.
[0034]
[0043] As discussed above, a trade-off exists between forward conduction current and reverse conduction current in power module 10. Because the footprint of power module 10 is limited by standards and practicality, the achievable forward and reverse conduction current of the power module is similarly limited by the space available for power semiconductor die 16. This is because the amount of current (forward conduction current) that IGBT 28 can pass is a function of the area of the semiconductor die dedicated to IGBT 28, and similarly, the amount of current (both forward conduction current and reverse conduction current) that MOSFET 30 can pass is a function of the area of the semiconductor die dedicated to MOSFET 30. MOSFETs pass more current in the reverse direction (from source to drain) than JBS diodes (anode to cathode) for the same semiconductor die area. Furthermore, MOSFETs can pass current in both directions (from source to drain and drain to source) due to their internal body diodes. IGBTs conduct more current in the forward direction (collector to emitter) than MOSFETs (drain to source) for the same area of the semiconductor die. Therefore, using IGBTs 28 and MOSFETs 30 in switch position SW of power module 10 allows for a better tradeoff between forward and reverse conduction current than was previously achievable. In one embodiment, power module 10:
[0035]
number
[0036] Amperes per square centimeter (A / cm 2 ) where V b(r) is the rated interrupting voltage of the power module. In one embodiment, the specific current rating applies to both the forward and reverse directions.
[0037]
[0044] As illustrated in FIG. 6, in addition to a better tradeoff between forward and reverse conduction current, the switch position SW of the power module 10 also provides a The use of SFET 30 improves the efficiency of power module 10. As shown, power module 10 including IGBT 28 and MOSFET 30 provides significantly higher DC efficiency, especially under light load conditions, than the corresponding power module 10 including IGBT 18 and diode 20 discussed above. Although not shown, both embodiments of power module 10 discussed above significantly surpass in their efficiency conventional power modules utilizing silicon devices as well as power modules including only MOSFETs.
[0038]
[0045] 4, switch position SW has a first control terminal 32 and a second control terminal 38. Providing separate control terminals for IGBT 28 and MOSFET 30 may enable several performance advantages to be realized by power module 10. In particular, IGBT 28 and MOSFET 30 may be individually controlled (e.g., by switching control signals from switching control circuitry, not shown) such that a switching control scheme may be used that minimizes switching losses in power module 10.
[0039]
[0046] 7 is a flow diagram illustrating a method for controlling the IGBT 28 and MOSFET 30 in the power module 10 to minimize switching losses, according to one embodiment of the present disclosure. First, the power module 10 may be switched from a forward conduction mode, in which current is conducted between the first power switching terminal 34 and the second power switching terminal 36, to a shutdown mode, in which current is not conducted between the first power switching terminal 34 and the second power switching terminal 36, by placing the IGBT 28 in shutdown mode before placing the MOSFET 30 in shutdown mode (step 100). Placing the IGBT 28 in shutdown mode before the MOSFET 30 reduces switching losses in the power module 10 because the IGBT 28 typically takes much longer to transition from forward conduction mode to shutdown mode due to the recombination time of minority carriers within the device.
[0040]
[0047] Second, power module 10 can be switched from blocking mode to forward conduction mode by placing MOSFET 30 in reverse conduction mode before placing IGBT 28 in forward conduction mode (step 102). Placing MOSFET 30 in reverse conduction mode before placing IGBT 28 in forward conduction mode mitigates reverse recovery losses by allowing charge to recombine rather than being swept out of the drift region by the reverse recovery process, thereby reducing switching losses in power module 10.
[0041]
[0048] In some embodiments, it may be desirable to also include a diode in switch position SW as discussed above with respect to Figure 4. Accordingly, Figure 8 is a functional schematic diagram illustrating switch position SW according to an alternative embodiment in which a diode 40 is provided in parallel with IGBT 28 and MOSFET 30. In particular, diode 40 includes an anode contact coupled to second power switching terminal 36 and a cathode coupled to first power switching terminal 34. Diode 40 may be provided by any number of power semiconductor dies 16 coupled in parallel as discussed above.
[0042]
[0049] FIG. 9 illustrates a conventional power module (solid line) in which the switch positions are formed by several silicon IGBTs and silicon PiN diodes; a power module (thick dashed line) in which the switch positions are formed by several silicon carbide MOSFETs using their internal body diodes for reverse current conduction; and a power module 10 (thin dashed line) in accordance with one embodiment of the present disclosure in which the switch positions are formed by several silicon carbide IGBTs and silicon carbide JBS diodes; 1 is a graph showing normalized output power versus normalized power loss for a power module 10 (dashed and dotted lines) according to one embodiment of the present disclosure formed with some silicon carbide IGBTs and some silicon carbide MOSFETs. As shown, all power modules utilizing silicon carbide provide much less loss than power modules utilizing silicon. Furthermore, power modules using silicon carbide IGBTs and JBS diodes provide much lower losses at low output power than power modules using only silicon carbide MOSFETs. The lowest overall losses are provided by power modules using IGBTs and MOSFETs as described herein.
[0043]
[0050] Figure 10 shows the amperes per square centimeter (A / cm ) of the power module 10. 2 ) As shown, the specific current rating of the power module 10 decreases as the voltage rating of the power module 10 increases. In one embodiment, the specific current rating of the power module is
[0044]
number
[0045] is greater than V b(r)is the rated interrupting voltage of the power module.
[0051] Those skilled in the art will recognize improvements and modifications to the preferred embodiments of the present disclosure, and all such improvements and modifications are considered within the scope of the concepts disclosed herein and the following claims.
Claims
1. a first power switching terminal and a second power switching terminal; a plurality of power semiconductor devices, at least one insulated gate bipolar junction transistor (IGBT); at least one metal oxide semiconductor field effect transistor (MOSFET); the at least one IGBT and the at least one MOSFET are coupled in parallel between the first power switching terminal and the second power switching terminal; The power module, wherein the at least one IGBT and the at least one MOSFET are silicon carbide semiconductor devices.
2. a collector contact of the at least one IGBT and a drain contact of the at least one MOSFET are coupled to the first power switching terminal; The power module of claim 1 , wherein an emitter contact of the at least one IGBT and a source contact of the at least one MOSFET are coupled to the second power switching terminal.
3. The power module of claim 2 further comprising a switching control terminal coupled to a gate contact of the at least one IGBT and a gate contact of the at least one MOSFET.
4. a first switching control terminal coupled to a gate contact of the at least one IGBT; 3. The power module of claim 2, further comprising: a second switching control terminal coupled to a gate contact of the at least one IGBT and the at least one MOSFET such that the at least one MOSFET is independently controlled.
5. a first switching control terminal coupled to a gate contact of the at least one IGBT; 10. The power module of claim 1 further comprising: a second switching control terminal coupled to a gate contact of the at least one MOSFET.
6. The power module of claim 1 , wherein the at least one IGBT comprises multiple IGBT semiconductor dies.
7. The power module of claim 6 , wherein the at least one MOSFET comprises multiple MOSFET semiconductor dies.
8. 10. The power module of claim 1, wherein the at least one MOSFET comprises multiple MOSFET semiconductor dies.
9. 10. The power module of claim 1, further comprising: at least one diode coupled in anti-parallel with the at least one IGBT and the at least one MOSFET between the first power switching terminal and the second power switching terminal.
10. 10. The power module of claim 9, wherein the at least one diode is a silicon carbide semiconductor device.
11. a collector contact of the at least one IGBT, a drain contact of the at least one MOSFET, and a cathode of the at least one diode are coupled to the first power switching terminal; 10. The power module of claim 9, wherein an emitter contact of the at least one IGBT, a source contact of the at least one MOSFET, and an anode of the at least one diode are coupled to the second power switching terminal.
12. The specific current rating of the power module is: [Equation 1] is greater than ｂ（ｒ） 10. The power module of claim 1, wherein: is the rated interrupting voltage of the power module.
13. a first power switching terminal and a second power switching terminal; a plurality of power semiconductor devices, at least one insulated gate bipolar junction transistor (IGBT); at least one diode; the at least one IGBT and the at least one diode are coupled in anti-parallel between the first power switching terminal and the second power switching terminal; The power module, wherein the at least one IGBT and the at least one diode are silicon carbide semiconductor devices.
14. a collector contact of the at least one IGBT and a cathode of the at least one diode are coupled to the first power switching terminal; 14. The power module of claim 13, wherein an emitter contact of the at least one IGBT and an anode contact of the at least one diode are coupled to the second power switching terminal.
15. 15. The power module of claim 14, wherein the at least one diode is a junction barrier Schottky diode.
16. The power module of claim 13 , wherein the at least one IGBT comprises a plurality of IGBTs.
17. 17. The power module of claim 16, wherein the at least one diode comprises a plurality of diodes.
18. A power module, a first power switching terminal, a second power switching terminal, and a control terminal; a plurality of semiconductor dies disposed between the first power switching terminal, the second power switching terminal, and the control terminal; the power module is configured to selectively conduct current between the first power switching terminal and the second power switching terminal based on a control signal provided at the control terminal; The specific current rating of the power module is: [Equation 2] is greater than ｂ（ｒ） is the rated interrupting voltage of the power module.
19. 1. A method of operating a power module comprising at least one silicon carbide insulated gate bipolar transistor (IGBT) and at least one metal oxide semiconductor field effect transistor (MOSFET) coupled in parallel, the method comprising: switching the power module from a forward conduction mode to a cutoff mode by placing the at least one IGBT in a cutoff mode before placing the at least one MOSFET in a cutoff mode; and switching the power module from the blocking mode to the forward conduction mode by placing the at least one MOSFET in a reverse conduction mode before placing the at least one IGBT in a forward conduction mode.