Power module integrated with semiconductor power chip
By embedding semiconductor power chips into printed circuit boards and equipping them with DC support capacitors and heat dissipation devices, the problems of low power density and cooling in existing power modules are solved, achieving more efficient dynamic current sharing and cooling effects.
Patent Information
- Application Number
- CN202422575569.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-24
- Publication Date
- 2025-10-17
- Estimated Expiration
- 2034-10-24
AI Technical Summary
Existing power modules suffer from low power density, high stray current, and difficulty in achieving effective cooling.
The semiconductor power chip is embedded inside the printed circuit board, and a copper base layer is set in the middle insulating layer to increase the number and thickness of the conductive layer. It is equipped with DC support capacitors and drive circuits and is cooled by heat dissipation devices.
It increases the power density of the power module, reduces stray inductance, improves dynamic current sharing, enhances cooling efficiency, and shortens the product development cycle.
Smart Images
Figure CN223452163U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the power module with semiconductor power chip, semiconductor power chip is integrated in printed circuit board (PCB) and especially two -dimensional electron gas formula structure's semiconductor chip, for example, GaN (gallium nitride) power chip. BACKGROUND
[0002] It is known that the power module can be used as an inverter for providing a control signal to an electric machine, for example, in an electric vehicle. Such a power module is typically used to convert a signal from a direct current power source into an alternating current signal and can comprise semiconductor power chips mounted on a PCB. However, such known power chips have the disadvantages of low power density, high stray current, and difficulty in implementing cooling, etc. SUMMARY
[0003] The utility model aims at solving at least one of the above problems and / or other problems in the prior art.
[0004] In particular, the present application provides a power module, comprising:
[0005] - a printed circuit board comprising a top layer and a bottom layer formed of an insulating matrix and a plurality of electrically conductive layers arranged between the top layer and the bottom layer, the plurality of electrically conductive layers being distributed along the thickness direction of the printed circuit board and separated by intermediate insulating layers formed of an insulating matrix; and
[0006] - a semiconductor power chip embedded in one of the intermediate insulating layers of the printed circuit board.
[0007] The utility model is characterized in that the semiconductor power chip is embedded in the interior of the printed circuit board, thereby allowing capacitors for absorbing signal spikes and auxiliary structures such as drive circuits to be arranged on the surface layer of the same printed circuit board, so that these auxiliary structures can be as close as possible to the power chip, thereby not only reducing stray inductance and improving dynamic current sharing, but also increasing the power density of the power module.
[0008] The utility model contains the following advantageous technical features, which can be applied individually or in any technically possible combination:
[0009] - a copper-based layer is arranged in the one intermediate insulating layer, and the semiconductor power chip is attached to the copper-based layer;
[0010] - the power module further comprises a direct current support capacitor arranged in the top layer of the printed circuit board and located between the direct current power source and the semiconductor power chip;
[0011] - the semiconductor power chips comprise GaN power chips;
[0012] - the printed circuit board has 8 conductive layers, the semiconductor power chips comprise 8 GaN power chips, the 8 GaN power chips are arranged in the middle insulating layer between the fourth conductive layer and the fifth conductive layer counted from the top layer of the printed circuit board;
[0013] - the semiconductor power chips further comprise 8 Si power chips arranged in the same middle insulating layer as the GaN power chips, each Si power chip is connected with one GaN power chip to form one half-bridge circuit, thereby forming 4 parallel upper bridge circuits and 4 parallel lower bridge circuits;
[0014] - the power module comprises 16 DC support capacitors, every 4 DC support capacitors are associated with a pair of upper and lower bridge circuits;
[0015] - the power module further comprises a driving circuit arranged in the top layer of the printed circuit board;
[0016] - the number and thickness of the conductive layers of the printed circuit board are determined according to the predetermined output power or output current of the power module;
[0017] - the power module further comprises a heat dissipation device, the printed circuit board is mounted on the heat dissipation device in a manner that the bottom layer of the printed circuit board is in face-to-face contact with the heat dissipation device. BRIEF DESCRIPTION OF DRAWINGS
[0018] The features and advantages of the present application will be understood by reading the detailed description provided herein with reference to the accompanying drawings. It is understood that the following drawings are not limiting in nature and are merely provided to illustrate the present application, in which:
[0019] Figure 1 shows a cross-sectional view of the PCB layout structure of the power module according to one preferred embodiment of the present application;
[0020] Figure 2 shows a top view of the PCB layout structure of the power module according to one preferred embodiment of the present application; and
[0021] Figure 3 shows a circuit schematic diagram of the semiconductor power chips of the power module according to one preferred embodiment of the present application. DETAILED DESCRIPTION
[0022] Embodiments of the present invention are described below with reference to the accompanying drawings. In the following description, many specific details are set forth so that those skilled in the art can more fully understand and implement the present invention. However, it will be apparent to those skilled in the art that the present invention may be implemented without some of these specific details. Furthermore, it should be understood that the present invention is not limited to the specific embodiments described. On the contrary, any combination of the features and elements described below may be considered to implement the present invention, regardless of whether they relate to different embodiments. Therefore, the following aspects, features, embodiments, and advantages are for illustrative purposes only and should not be considered as elements or limitations of the claims unless expressly set forth in the claims.
[0023] The present invention relates to a power module that receives electrical signals from a DC power supply and converts them into AC signals for use, for example, in controlling a three-phase AC motor. This power module can be advantageously applied in various fields, such as automotive, industrial control, and power supply, and typically includes a semiconductor power chip, such as a Si power chip, a SiC power chip, or a GaN power chip, arranged on a printed circuit board.
[0024] The power module according to the present invention may include a printed circuit board (PCB) and a semiconductor power chip. The PCB may have a multi-layer structure, and the semiconductor power chip is embedded in a middle layer of the PCB. In particular, the semiconductor power chip may be a semiconductor chip having a two-dimensional electron gas structure, particularly a GaN chip.
[0025] See also Figure 1 In a preferred embodiment of the present invention, the printed circuit board may include a top layer 11 and a bottom layer 19 formed of an insulating matrix, and may include a plurality of conductive layers 21, 22, 23, 24, 25, 26, 27, 28 (in the embodiment) disposed between the top layer 11 and the bottom layer 19. Figure 1 These conductive layers 21-28 can be formed of a conductive material, in particular copper, and are distributed along the thickness direction of the printed circuit board and separated by intermediate insulating layers 12, 13, 14, 15, 16, 17, 18 formed of an insulating matrix. These conductive layers 21-28 can be connected to each other via a plurality of vias 29 (in the middle) also formed of a conductive material such as copper. Figure 1 The semiconductor power chip 3 is embedded in an intermediate insulating layer of the printed circuit board, for example, Figure 1 As shown, it is embedded in the intermediate insulating layer 15 between the fourth conductive layer 24 and the fifth conductive layer 25 counted from the top layer 11 of the printed circuit board.
[0026] Advantageously, as Figure 1As shown in Fig. 1, the thickness of the conductive layers (here, conductive layers 21, 28) of the printed circuit board adjacent to the top layer 11 and the bottom layer 19 of the insulating material thereof can be smaller than the thickness of at least a portion of the conductive layers (here, conductive layers 22, 23, 26, 27) in the middle. Also advantageously, the thickness of the conductive layers (here, conductive layers 24, 25) on both sides of the middle insulating layer 15 in which the semiconductor power chip 3 is embedded can be smaller than the thickness of the other middle conductive layers. The thickness of the conductive layers 21-28 can be in the range of tens to hundreds of micrometers.
[0027] It should be noted here that the number and thickness of the conductive layers (and the middle insulating layers thereof) described above are exemplary. In the power module of the present application, the number and thickness of the conductive layers in the printed circuit board can vary depending on the designed or required output power or output current.
[0028] By embedding the semiconductor power chip in the printed circuit board, the present application gives the printed circuit board of the power module more design space, so that more related devices or apparatuses can be arranged on the surface layer of the printed circuit board, and they are closer to the semiconductor power chip due to being arranged on the same printed circuit board as the semiconductor power chip. For example, as will be described in detail below, a capacitor or a driving circuit, etc. can be provided on the top layer 11 of the printed circuit board for reducing stray inductance, or a cooling apparatus can be connected on the bottom layer 19 of the printed circuit board for improving the cooling efficiency of the entire power module. Moreover, the present application allows more power chips to be arranged in the printed circuit board, thereby the power density of the printed circuit board can be improved. Finally, in the case that the size of the printed circuit board does not change, the present application allows different power series of power chips to be quickly replaced, advantageously shortening the development cycle of the product.
[0029] Still referring to Fig. 1, Figure 1 Preferably, a copper-based layer 4 can be provided in the middle insulating layer 15 for embedding the semiconductor power chip 3, and the semiconductor power chip 3 can be attached on the copper-based layer 4. Here, the semiconductor power chip 3 can be attached to the copper-based layer 4, for example, via a silver sintering chip attachment layer 5.
[0030] Figure 1 The preferred embodiment shown in which the semiconductor power chip 3 is in close contact with the copper-based layer 4 has the advantages of low thermal resistance, good heat dissipation effect, etc.
[0031] Particularly preferably, the semiconductor power chip 3 can include a GaN power chip 31. In this case, the copper-based layer 4 can be a copper-based layer 41 made of copper or a copper alloy, and the silver sintering chip attachment layer 5 can be a silver sintering chip attachment layer 51 made of silver or a silver alloy. Figure 1In the embodiment shown, the printed circuit board has eight conductive layers. The semiconductor power chips 3 can comprise eight GaN power chips 31. These GaN power chips 31 can all be arranged in the middle insulating layer 15 of the printed circuit board and can be divided into two groups, each group comprising four GaN power chips 31 connected in parallel, as can be seen from Figure 2 and Figure 3 .
[0032] The provision of such semiconductor power chips 3 makes the routing of the printed circuit board more flexible and the dynamic current sharing between the semiconductor power chips connected in parallel even better.
[0033] In the embodiment shown in Figure 2 and Figure 3 , the semiconductor power chips 3 can also comprise Si power chips 32. The Si power chips 32 can be provided in the same insulating layers as the GaN power chips 31, in particular in the middle insulating layer 15, and can have the same number as the GaN power chips 31.
[0034] As shown in Figure 3 , each Si power chip 32 can form a half-bridge circuit in combination with one GaN power chip 31. In this way, the upper bridge circuit 33 can comprise one GaN power chip 31 (for example in the form of an N-type transistor) and one Si power chip 32 (for example in the form of a P-type transistor). Similarly, the lower bridge circuit 34 can also comprise one GaN power chip 31 and one Si power chip 32.
[0035] For the upper bridge circuit 33, the control electrode of the GaN power chip 31 is coupled to the gate control terminal Gate, the first electrode is coupled to the positive connection terminal HV+ of the DC power supply, and the second electrode is coupled to the first electrode of the Si power chip 32. The control electrode of the Si power chip 32 is coupled to the enable control terminal Enable, and the second electrode is coupled to the output terminal Phase. For the lower bridge circuit 34, the first electrode of the GaN power chip 31 is coupled to the negative connection terminal HV- of the DC power supply, and the others are similar to the upper bridge circuit 33, which will not be described here. The upper bridge circuit 33 and the lower bridge circuit 34 respectively provide the forward current from the positive connection terminal HV+ of the DC power supply or the reverse current from the negative connection terminal HV- of the DC power supply to the output terminal Phase based on the gate control signal from the gate control terminal Gate and the enable signal from the enable control terminal Enable.
[0036] It should be understood that the gate control signals provided to the upper bridge circuit 33 and the lower bridge circuit 34 can be different, and the enable signals provided to the upper bridge circuit 33 and the lower bridge circuit 34 can also be different.
[0037] In addition, the upper bridge circuit 33 and the lower bridge circuit 34 further comprise a Kelvin Source coupled with the first pole of the Si power chip 32 and a diode D.
[0038] By controlling the timing of the gate control signals and the enable signals respectively provided to the upper bridge circuit 33 and the lower bridge circuit 34, the duty cycle and the frequency of the alternating current output from the output terminal Phase can be controlled. The output alternating current can be supplied to one phase of an alternating current motor as a phase control signal.
[0039] In an embodiment in which the power module comprises eight GaN power chips 31 and eight Si power chips 32, as shown in Figure 3 they can be divided into two groups as described above, each group comprising four pairs of GaN power chips 31 and Si power chips 32 in combination, the four pairs being connected in parallel, thereby forming four parallel upper bridge circuits and four parallel lower bridge circuits.
[0040] Of course, the number and the type of the semiconductor power chips in the power module of the present application are not limited to the specific embodiments described above. In particular, the number of GaN power chips 31 and Si power chips 32 can be greater or less than eight, for example, two GaN power chips 31 and two Si power chips 32 can be provided. For another example, the semiconductor power chips can comprise SiC power chips.
[0041] Similar to the number of layers of the printed circuit board, in the present application, the number of semiconductor power chips can be determined according to the required output power, in particular. For example, when the required output power is large or small, the number of power chips connected in parallel in each group of semiconductor power chips can be increased or decreased.
[0042] The provision of the parallel semiconductor power chips in the present application makes the wiring of the printed circuit board more flexible, and has the effect of better dynamic current sharing between the parallel semiconductor power chips.
[0043] Returning to Figure 2 According to a preferred embodiment of the present application, the power module can further comprise a direct current link capacitor (DCLink) 6, which can be mounted on the surface layer, i.e. the top layer 11 of the printed circuit board, and located between the direct current power supply and the semiconductor power chips. For example, the direct current link capacitor 6 can be coupled between the positive connection terminal HV+ of the direct current power supply and the semiconductor power chips 3, for absorbing the peak signals and other stray signals from the positive connection terminal HV+ and leading them to the grounding point or ground electrode; and / or, the direct current link capacitor 6 can be coupled between the negative connection terminal HV- of the direct current power supply and the semiconductor power chips 3, for absorbing the peak signals and other stray signals from the negative connection terminal HV- and leading them to the grounding point or ground electrode.
[0044] In the embodiment shown in Fig. 1, the power module comprises eight GaN power chips 31 and optional Si power chips 32 forming four pairs of half-bridge circuits. The power module can comprise sixteen DC support capacitors 6, and each four DC support capacitors 6 are associated with one pair of half-bridge circuits. Figure 2
[0045] In this way, a DC signal from an external power source can enter the power module via a positive connection terminal HV+ or a negative connection terminal HV- on the printed circuit board, enter a pair of mutually connected GaN power chips 31 and Si power chips 32 (for example, the two power chips 31, 32 in the second column from the left in Fig. 1, which form an upper bridge circuit) after flowing through every four DC support capacitors 6 (for example, the first four from the left in Fig. 1), and then enter another pair of mutually connected GaN power chips 31 and Si power chips 32 (for example, the two power chips 31, 32 in the first column from the left in Fig. 1, which form a lower bridge circuit) coupled thereto, and the AC signal thus formed can be delivered to a device to be controlled, such as a motor, via an output terminal Phase as a control signal for one phase of the motor. In this process, stray signals such as spike signals in the electrical signal can be absorbed by the four DC support capacitors 6 and directed to the ground electrode to be eliminated. Figure 2 Figure 2 Figure 2 The other three groups (each group comprising four DC support capacitors 6 and two GaN power chips 31 and two Si power chips 32) shown in the embodiment of Fig. 1 are in parallel with the first group described above and work in the same way. In this way, the power module of the present embodiment can achieve a power module function of, for example, 200 KW.
[0046] Figure 2 Of course, the utility model can also include a large capacitor arranged between the printed circuit board and the DC power source in addition to the printed circuit board, for preliminary absorption of large spike noise signals.
[0047] According to the preferred embodiment of the utility model, the power module further comprises a drive circuit 7 arranged in the top layer 11 of the printed circuit board.
[0048] The above-mentioned embodiment enables the DC support capacitors 6 and the drive circuit 7 to be closer to the semiconductor power chips, thereby not only reducing stray inductance, but also providing the power density of the printed circuit board.
[0049] The above-mentioned embodiment enables the DC support capacitors 6 and the drive circuit 7 to be closer to the semiconductor power chips, thereby not only reducing stray inductance, but also providing the power density of the printed circuit board.
[0050] Finally, preferably, the power module of the application can further comprise a heat dissipation device, such as a heat sink. The printed circuit board of the power module can be mounted on the heat dissipation device in such a way that its bottom layer 19 is in face-to-face contact with the heat dissipation device. Such a solution further improves the cooling effect of the power module, thereby advantageously ensuring the working efficiency and service life of the power module.
[0051] Various modifications and changes can be made to the embodiments disclosed herein without departing from the scope or spirit of the application. Other embodiments of the application will be apparent to those of ordinary skill in the art from consideration of the specification and practice of the application as disclosed herein. This specification and the examples provided are to be considered exemplary only, with the true scope of the application being indicated by the following claims and their equivalents.
Claims
1. A power module, characterized in that: The power module includes: - a printed circuit board comprising a top layer (11) and a bottom layer (19) formed of an insulating matrix and a plurality of conductive layers (21, 22, 23, 24, 25, 26, 27, 28) arranged between the top layer (11) and the bottom layer (19), the plurality of conductive layers (21, 22, 23, 24, 25, 26, 27, 28) being distributed in a thickness direction of the printed circuit board and being separated by intermediate insulating layers (12, 13, 14, 15, 16, 17, 18) formed of an insulating matrix; and - a semiconductor power chip (3), said semiconductor power chip (3) being embedded in an intermediate insulating layer (15) of said printed circuit board.
2. The power module according to claim 1, wherein: A copper base layer (4) is provided in the intermediate insulating layer (15), and the semiconductor power chip (3) is mounted on the copper base layer (4).
3. The power module according to claim 1 or 2, characterized in that: The power module further comprises a DC support capacitor (6) arranged in the top layer (11) of the printed circuit board and located between the DC power supply and the semiconductor power chip (3).
4. The power module according to claim 3, wherein: The semiconductor power chip (3) includes a GaN power chip (31).
5. The power module according to claim 4, characterized in that: The printed circuit board has eight conductive layers (21, 22, 23, 24, 25, 26, 27, 28), the semiconductor power chip (3) includes eight GaN power chips (31), and the eight GaN power chips (31) are arranged in an intermediate insulating layer (15) between a fourth conductive layer (24) and a fifth conductive layer (25) counted from a top layer (11) of the printed circuit board.
6. The power module according to claim 5, characterized in that: The semiconductor power chip (3) further comprises eight Si power chips (32) arranged in the same intermediate insulating layer (15) as the GaN power chip (31); each Si power chip (32) is connected to one GaN power chip (31) to form a half-bridge circuit, thereby forming four parallel upper bridge circuits (33) and four parallel lower bridge circuits (34).
7. The power module according to claim 6, characterized in that: The power module comprises 16 DC link capacitors (6), and every four DC link capacitors (6) are associated with a pair of an upper bridge circuit (33) and a lower bridge circuit (34).
8. The power module according to claim 1 or 2, characterized in that: The power module further comprises a driving circuit (7) arranged in a top layer (11) of the printed circuit board.
9. The power module according to claim 1 or 2, characterized in that: The number and thickness of the conductive layers (21, 22, 23, 24, 25, 26, 27, 28) of the printed circuit board are determined according to a predetermined output power or output current of the power module.
10. The power module according to claim 1 or 2, characterized in that: The power module further comprises a heat sink, on which the printed circuit board is mounted in a manner such that a bottom layer (19) of the printed circuit board is in face-to-face contact with the heat sink.