Packaging structure of three-phase full-bridge power module of integrated ceramic capacitor

Abstract

The invention provides a packaging structure of a three-phase full-bridge power module of an integrated ceramic capacitor. The packaging structure comprises a ceramic substrate, an A-phase bridge arm, a B-phase bridge arm and a C-phase bridge arm, wherein the A-phase bridge arm, the B-phase bridge arm and the C-phase bridge arm are arranged on the front surface of the ceramic substrate; wherein the positive bus copper foil of the A-phase bridge arm, the positive bus copper foil of the B-phase bridge arm and the positive bus copper foil of the C-phase bridge arm are communicated, and A-phase ceramic capacitors are arranged on the left part of the positive bus copper foil of the A-phase bridge arm and the A-phase negative bus copper foil; b-phase ceramic capacitors are arranged on the middle part of the positive bus copper foil of the B-phase bridge arm and the B-phase negative bus copper foil; and a C-phase ceramic capacitor is arranged on the right part of the positive bus copper foil of the C-phase bridge arm and the C-phase negative bus copper foil. The ceramic capacitors are integrated in the packaging structure, so that the stray inductance of each power loop is reduced, the voltage spike and oscillation in the commutation process are suppressed, and the electromagnetic interference noise is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of power semiconductor module packaging and integration, and in particular to a packaging structure of a three-phase full-bridge power module with integrated ceramic capacitors. Background Art

[0002] Driven by the application backgrounds of aerospace, electric vehicles and robots, high power density and high efficiency motor drives are urgently needed. Power semiconductor modules play a decisive role in the performance of motor drives. At present, the performance of power modules based on traditional semiconductor silicon has reached its limit and it is difficult to improve it significantly, which directly affects the improvement of motor drive performance. The third-generation wide bandgap semiconductor materials have obvious advantages in material properties such as critical breakdown field strength, relative dielectric constant and thermal conductivity. The power semiconductor modules made of them have higher switching speed, lower on-resistance and better thermal characteristics than traditional silicon-based power semiconductor modules. It can be seen that wide bandgap power semiconductor modules have advantages in achieving high power density and high efficiency motor drives. However, at high switching speeds, wide bandgap power semiconductor modules are more sensitive to the stray inductance introduced by the package, which will produce larger voltage overshoot and larger switching oscillation, increase voltage stress and electromagnetic interference noise, etc. Therefore, in the design of power module packaging structure for motor drives, it is necessary to further reduce parasitic inductance, so as to give full play to the advantages of wide bandgap semiconductors and improve the performance of motor drives. Summary of the invention

[0003] In view of this, the present application provides a packaging structure of a three-phase full-bridge power module with integrated ceramic capacitors to solve the above technical problems.

[0004] The present application embodiment provides a packaging structure of a three-phase full-bridge power module with integrated ceramic capacitors, comprising: a ceramic substrate and an A-phase bridge arm, a B-phase bridge arm and a C-phase bridge arm arranged on the front surface of the ceramic substrate; wherein the positive busbar copper foils of the A-phase bridge arm, the B-phase bridge arm and the C-phase bridge arm are connected;

[0005] The A-phase bridge arm comprises: an A-phase upper bridge arm driving gate copper foil and an A-phase upper bridge arm driving source copper foil arranged above the left part of the positive bus copper foil, an A-phase negative bus copper foil and an A-phase output copper foil arranged below the left part of the positive bus copper foil, an A-phase lower bridge arm driving gate copper foil and an A-phase lower bridge arm driving source copper foil arranged directly below the A-phase output copper foil, an A-phase upper bridge arm power chip arranged on the left part of the positive bus copper foil, an A-phase lower bridge arm power chip arranged on the A-phase output copper foil, and an A-phase ceramic capacitor arranged on the left part of the positive bus copper foil and the A-phase negative bus copper foil;

[0006] The B-phase bridge arm comprises: a B-phase upper bridge arm driving gate copper foil and a B-phase upper bridge arm driving source copper foil arranged above the middle part of the positive bus copper foil, a B-phase negative bus copper foil and a B-phase output copper foil arranged below the middle part of the positive bus copper foil, a B-phase lower bridge arm driving gate copper foil and a B-phase lower bridge arm driving source copper foil arranged directly below the B-phase output copper foil, a B-phase upper bridge arm power chip arranged on the middle part of the positive bus copper foil, a B-phase lower bridge arm power chip arranged on the B-phase output copper foil, and a B-phase ceramic capacitor arranged on the middle part of the positive bus copper foil and the B-phase negative bus copper foil;

[0007] The C-phase bridge arm comprises: a C-phase upper bridge arm driving gate copper foil and a C-phase upper bridge arm driving source copper foil arranged above the right part of the positive bus copper foil, a C-phase negative bus copper foil and a C-phase output copper foil arranged below the right part of the positive bus copper foil, a C-phase lower bridge arm driving gate copper foil and a C-phase lower bridge arm driving source copper foil arranged directly below the C-phase output copper foil; a C-phase upper bridge arm power chip arranged on the right part of the positive bus copper foil, a C-phase lower bridge arm power chip arranged on the C-phase output copper foil, and a C-phase ceramic capacitor arranged on the right part of the positive bus copper foil and the C-phase negative bus copper foil;

[0008] The left part of the positive bus copper foil, the A-phase output copper foil and the A-phase negative bus copper foil constitute the A-phase power circuit; the middle part of the positive bus copper foil, the B-phase output copper foil and the B-phase negative bus copper foil constitute the B-phase power circuit; the right part of the positive bus copper foil, the C-phase output copper foil and the C-phase negative bus copper foil constitute the C-phase power circuit; the layout of the A-phase power circuit, the B-phase power circuit and the C-phase power circuit are the same;

[0009] The position of the A-phase ceramic capacitor in the A-phase power circuit, the position of the B-phase ceramic capacitor in the B-phase power circuit, and the position of the C-phase ceramic capacitor in the C-phase power circuit are the same.

[0010] The packaging structure of the present application integrates ceramic capacitors, which reduces the stray inductance of each power circuit, suppresses voltage spikes and oscillations during the commutation process, and reduces electromagnetic interference noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the specific implementation methods of the present application or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0012] Figure 1 A schematic top view of the structure of a copper-clad ceramic substrate according to an embodiment of the present application;

[0013] Figure 2 A schematic diagram of the packaging structure of a three-phase full-bridge module with integrated ceramic capacitors according to an embodiment of the present application;

[0014] Figure 3 This is an internal structure diagram of the packaging structure of a three-phase full-bridge module with integrated ceramic capacitors according to an embodiment of the present application;

[0015] Figure 4 A rear view of the copper-clad ceramic substrate according to an embodiment of the present application;

[0016] Figure 5 A side view of a copper-clad ceramic substrate according to an embodiment of the present application;

[0017] Figure 6 A circuit topology diagram of a three-phase full-bridge module with integrated ceramic capacitors proposed in an embodiment of the present application;

[0018] Reference numerals:

[0019] 1: copper-clad ceramic substrate; 1-2: ceramic substrate; 1-3: copper foil layer; 1-4: round hole;

[0020] 2: A phase bridge arm; 3: B phase bridge arm; 4: C phase bridge arm;

[0021] 5: positive busbar copper foil; 6: A-phase negative busbar copper foil; 7: B-phase negative busbar copper foil;

[0022] 8: C phase negative busbar copper foil; 9: A phase output copper foil; 10: B phase output copper foil;

[0023] 11: C phase output copper foil; 12: A phase upper bridge arm drive gate copper foil;

[0024] 13: A phase upper bridge arm driving source copper foil; 14: A phase lower bridge arm driving gate copper foil;

[0025] 15: A phase lower bridge arm driving source copper foil; 16: B phase upper bridge arm driving gate copper foil;

[0026] 17: B-phase upper bridge arm driving source copper foil; 18: B-phase lower bridge arm driving gate copper foil;

[0027] 19: B phase lower bridge arm driving source copper foil; 20: C phase upper bridge arm driving gate copper foil;

[0028] 21: C phase upper bridge arm driving source copper foil; 22: C phase lower bridge arm driving gate copper foil;

[0029] 23: C phase lower bridge arm driving source copper foil; 24: A phase upper bridge arm power chip;

[0030] 25: A-phase lower bridge arm power chip; 26: B-phase upper bridge arm power chip;

[0031] 27: B-phase lower bridge arm power chip; 28: C-phase upper bridge arm power chip;

[0032] 29: C-phase lower bridge arm power chip; 30a: first positive bus terminal;

[0033] 30b: first positive bus terminal; 30c: first positive bus terminal;

[0034] 31: A phase output terminal; 32: B phase output terminal; 33-C phase output terminal;

[0035] 34: A-phase negative bus terminal; 35: B-phase negative bus terminal; 36: C-phase negative bus terminal;

[0036] 37: A phase upper bridge arm driving gate terminal; 38: A phase upper bridge arm driving source terminal;

[0037] 39: A-phase lower bridge arm driving gate terminal; 40: A-phase lower bridge arm driving source terminal;

[0038] 41: B-phase upper bridge arm driving gate terminal; 42: B-phase upper bridge arm driving source terminal;

[0039] 43: B-phase lower bridge arm driving gate terminal; 44: B-phase lower bridge arm driving source terminal;

[0040] 45: C phase upper bridge arm driving gate terminal; 46: C phase upper bridge arm driving source terminal;

[0041] 47: C phase lower bridge arm driving gate terminal; 48: C phase lower bridge arm driving source terminal;

[0042] 49: first power bonding wire; 50: second power bonding wire; 51: third power bonding wire;

[0043] 52: fourth power bonding wire; 53: fifth power bonding wire; 54: sixth power bonding wire;

[0044] 55: first driving gate bonding wire; 56: first Kelvin source bonding wire;

[0045] 57: second driving gate bonding wire; 58: second Kelvin source bonding wire;

[0046] 59: third driving gate bonding wire; 60: third Kelvin source bonding wire;

[0047] 61: fourth driving gate bonding wire; 62: fourth Kelvin source bonding wire;

[0048] 63: fifth driving gate bonding wire; 64: fifth Kelvin source bonding wire;

[0049] 65: sixth driving gate bonding wire; 66: sixth Kelvin source bonding wire;

[0050] 67: first solder resist layer; 68: second solder resist layer; 69: third solder resist layer;

[0051] 70: A-phase ceramic capacitor; 71: B-phase ceramic capacitor; 72: C-phase ceramic capacitor;

[0052] 73: A-phase bridge arm circuit; 74: B-phase bridge arm circuit; 75: C-phase bridge arm circuit. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0054] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0055] First, the design concept of the embodiments of the present application is briefly introduced.

[0056] In order to improve the performance of power semiconductor modules for motor drivers, the present application provides a low stray inductance three-phase full-bridge power module packaging structure based on integrated ceramic capacitors, including: a ceramic substrate and an A-phase bridge arm, a B-phase bridge arm and a C-phase bridge arm arranged on the front of the ceramic substrate; wherein the positive bus copper foils of the A-phase bridge arm, the B-phase bridge arm and the C-phase bridge arm are connected, and the A-phase ceramic capacitor is arranged on the left part of the positive bus copper foil and the A-phase negative bus copper foil; the B-phase ceramic capacitor is arranged on the middle part of the positive bus copper foil and the B-phase negative bus copper foil; and the C-phase ceramic capacitor is arranged on the right part of the positive bus copper foil and the C-phase negative bus copper foil. The position of the A-phase ceramic capacitor in the A-phase power circuit, the position of the B-phase ceramic capacitor in the B-phase power circuit, and the position of the C-phase ceramic capacitor in the C-phase power circuit are the same.

[0057] The beneficial effects of this application are:

[0058] 1. The packaging structure of the present application shortens the commutation path by optimizing the layout of the upper copper foil of the copper-clad ceramic substrate, so that the power circuit of each phase bridge arm remains consistent, thereby achieving consistency of the stray parameters of each bridge arm;

[0059] 2. This application achieves a shorter commutation loop path length by optimizing the upper copper foil layout, compact layout of the power chip, and position setting of the terminal; ceramic capacitors are integrated between the positive and negative bus copper foils of each phase loop, limiting high-frequency oscillations to the power chip-copper foil-bonding wire-ceramic capacitor, achieving decoupling of the internal power loop from the power terminal and external wiring, reducing the stray inductance of each power loop, suppressing voltage spikes and oscillations during the commutation process, and reducing electromagnetic interference noise;

[0060] 3. The drive circuit of the present application adopts the Kelvin connection method to reduce the common source inductance, which helps to reduce the coupling between the main power circuit and the drive circuit, reduce the negative feedback effect of the common source inductance on the drive circuit, and reduce the switching loss.

[0061] After introducing the application scenarios and design concepts of the embodiments of the present application, the technical solutions provided by the embodiments of the present application are described below.

[0062] like Figure 1 and Figure 2 As shown, the embodiment of the present application provides a packaging structure of an integrated ceramic capacitor three-phase full-bridge power module, including: a ceramic substrate 1-2 and an A-phase bridge arm 2, a B-phase bridge arm 3 and a C-phase bridge arm 4 arranged on the front side of the ceramic substrate 1-2; wherein the positive busbar copper foil 5 of the A-phase bridge arm 2, the B-phase bridge arm 3 and the C-phase bridge arm 4 are connected,

[0063] The A-phase bridge arm 2 includes: an A-phase upper bridge arm driving gate copper foil 12 and an A-phase upper bridge arm driving source copper foil 13 arranged above the left part of the positive bus copper foil 5, an A-phase negative bus copper foil 6 and an A-phase output copper foil 9 arranged below the left part of the positive bus copper foil 5, an A-phase lower bridge arm driving gate copper foil 14 and an A-phase lower bridge arm driving source copper foil 15 arranged directly below the A-phase output copper foil 9, an A-phase upper bridge arm power chip 24 arranged on the left part of the positive bus copper foil 5, an A-phase lower bridge arm power chip 25 arranged on the A-phase output copper foil 9, and an A-phase ceramic capacitor 70 arranged on the left part of the positive bus copper foil 5 and the A-phase negative bus copper foil 6;

[0064] The B-phase bridge arm 3 includes: a B-phase upper bridge arm driving gate copper foil 16 and a B-phase upper bridge arm driving source copper foil 17 arranged above the middle part of the positive bus copper foil 5, a B-phase negative bus copper foil 7 and a B-phase output copper foil 10 arranged below the middle part of the positive bus copper foil 5, a B-phase lower bridge arm driving gate copper foil 18 and a B-phase lower bridge arm driving source copper foil 19 arranged directly below the B-phase output copper foil 10, a B-phase upper bridge arm power chip 26 arranged on the middle part of the positive bus copper foil 5, a B-phase lower bridge arm power chip 27 arranged on the B-phase output copper foil 10, and a B-phase ceramic capacitor 71 arranged on the middle part of the positive bus copper foil 5 and the B-phase negative bus copper foil 7;

[0065] The C-phase bridge arm 4 includes: a C-phase upper bridge arm driving gate copper foil 20 and a C-phase upper bridge arm driving source copper foil 21 arranged above the right part of the positive bus copper foil 5, a C-phase negative bus copper foil 8 and a C-phase output copper foil 11 arranged below the right part of the positive bus copper foil 5, a C-phase lower bridge arm driving gate copper foil 22 and a C-phase lower bridge arm driving source copper foil 23 arranged directly below the C-phase output copper foil 11; a C-phase upper bridge arm power chip 28 arranged on the right part of the positive bus copper foil 5, a C-phase lower bridge arm power chip 29 arranged on the C-phase output copper foil 11, and a C-phase ceramic capacitor 72 arranged on the right part of the positive bus copper foil 5 and the C-phase negative bus copper foil 8;

[0066] The left part of the positive bus copper foil 5, the A-phase output copper foil 9 and the A-phase negative bus copper foil 6 constitute the A-phase power circuit; the middle part of the positive bus copper foil 5, the B-phase output copper foil 10 and the B-phase negative bus copper foil 7 constitute the B-phase power circuit; the right part of the positive bus copper foil 5, the C-phase output copper foil 11 and the C-phase negative bus copper foil 8 constitute the C-phase power circuit; the layout of the A-phase power circuit, the B-phase power circuit and the C-phase power circuit are the same;

[0067] The position of the A-phase ceramic capacitor 70 in the A-phase power circuit, the position of the B-phase ceramic capacitor 71 in the B-phase power circuit, and the position of the C-phase ceramic capacitor 72 in the C-phase power circuit are the same.

[0068] In some embodiments, Figure 1 As shown, a first solder resist layer 67 is disposed under the A-phase ceramic capacitor 70; a second solder resist layer 68 is disposed under the B-phase ceramic capacitor 71; and a third solder resist layer 69 is disposed under the C-phase ceramic capacitor 72. The pads of the ceramic capacitors are welded within the solder resist range to prevent solder from flowing into areas that do not require welding during the welding process, so as to locate the welding position.

[0069] In some embodiments, Figure 2As shown, the source of the A-phase upper bridge arm power chip 24 is connected to the A-phase output copper foil 9 through the first power bonding wire 49, the gate of the A-phase upper bridge arm power chip 24 is connected to the A-phase upper bridge arm drive gate copper foil 12 through the first drive gate bonding wire 55, and the source of the A-phase upper bridge arm power chip 24 is connected to the A-phase upper bridge arm drive source copper foil 13 through the first Kelvin source bonding wire 56; the A-phase lower bridge arm power chip 25 is connected to the A-phase negative bus copper foil 6 through the second power bonding wire 50, the gate of the A-phase lower bridge arm power chip 25 is connected to the A-phase lower bridge arm drive gate copper foil 14 through the second drive gate bonding wire 57, and the source of the A-phase lower bridge arm power chip 25 is connected to the A-phase lower bridge arm drive source copper foil 15 through the second Kelvin source bonding wire 58.

[0070] In some embodiments, Figure 3 As shown, the A-phase upper bridge arm driving gate terminal 37 is welded on the A-phase upper bridge arm driving gate copper foil 12, the A-phase upper bridge arm driving source terminal 38 is welded on the A-phase upper bridge arm driving source copper foil 13, the A-phase lower bridge arm driving gate terminal 39 is welded on the A-phase lower bridge arm driving gate copper foil 14, and the A-phase lower bridge arm driving source terminal 40 is welded on the A-phase lower bridge arm driving source copper foil 15.

[0071] In some embodiments, Figure 2 As shown, the source of the B-phase upper bridge arm power chip 26 is connected to the B-phase output copper foil 10 through the third power bonding wire 51, the gate of the B-phase upper bridge arm power chip 26 is connected to the B-phase upper bridge arm drive gate copper foil 16 through the third drive gate bonding wire 59, and the source of the B-phase upper bridge arm power chip 26 is connected to the B-phase upper bridge arm drive source copper foil 17 through the third Kelvin source bonding wire 60; the B-phase lower bridge arm power chip 27 is connected to the B-phase negative bus copper foil 7 through the fourth power bonding wire 52, the gate of the B-phase lower bridge arm power chip 27 is connected to the B-phase upper bridge arm drive gate copper foil 18 through the fourth drive gate bonding wire 61, and the source of the B-phase lower bridge arm power chip 27 is connected to the B-phase lower bridge arm drive source copper foil 19 through the fourth Kelvin source bonding wire 62.

[0072] In some embodiments, Figure 3 As shown, the B-phase upper bridge arm driving gate terminal 41 is welded on the B-phase upper bridge arm driving gate copper foil 16, the B-phase upper bridge arm driving source terminal 42 is welded on the B-phase upper bridge arm driving source copper foil 17, the B-phase lower bridge arm driving gate terminal 43 is welded on the B-phase lower bridge arm driving gate copper foil 18, and the B-phase lower bridge arm driving source terminal 44 is welded on the B-phase lower bridge arm driving source copper foil 19.

[0073] In some embodiments, Figure 2As shown, the source of the C-phase upper bridge arm power chip 28 is connected to the C-phase output copper foil 11 through the fifth power bonding wire 53, the gate of the C-phase upper bridge arm power chip 28 is connected to the C-phase upper bridge arm drive gate copper foil 20 through the fifth drive gate bonding wire 63, and the source of the C-phase upper bridge arm power chip 28 is connected to the C-phase upper bridge arm drive source copper foil 21 through the fifth Kelvin source bonding wire 64; the C-phase lower bridge arm power chip 29 is connected to the C-phase negative bus copper foil 8 through the sixth power bonding wire 54, the gate of the C-phase lower bridge arm power chip 29 is connected to the C-phase upper bridge arm drive gate copper foil 22 through the sixth drive gate bonding wire 65, and the source of the C-phase lower bridge arm power chip 29 is connected to the C-phase lower bridge arm drive source copper foil 19 through the sixth Kelvin source bonding wire 66.

[0074] In some embodiments, Figure 3 As shown, the C-phase upper bridge arm driving gate terminal 45 is welded on the C-phase upper bridge arm driving gate copper foil 20, the C-phase upper bridge arm driving source terminal 46 is welded on the C-phase upper bridge arm driving source copper foil 21, the C-phase lower bridge arm driving gate terminal 47 is welded on the C-phase lower bridge arm driving gate copper foil 22, and the C-phase lower bridge arm driving source terminal 48 is welded on the C-phase lower bridge arm driving source copper foil 23.

[0075] In some embodiments, Figure 3 As shown, a first positive bus terminal 30a is arranged above the A-phase ceramic capacitor 70 on the positive bus copper foil 5, a second positive bus terminal 30b is arranged above the B-phase ceramic capacitor 71 on the positive bus copper foil 5, and a third positive bus terminal 30c is arranged above the C-phase ceramic capacitor 72 on the positive bus copper foil 5; an A-phase output terminal 31 is welded on the A-phase output copper foil 9, a B-phase output terminal 32 is welded on the B-phase output copper foil 10, and a C-phase output terminal 33 is welded on the C-phase output copper foil 11; an A-phase negative bus terminal 34 is welded on the A-phase negative bus copper foil 6, a B-phase negative bus terminal 35 is welded on the B-phase negative bus copper foil 7, and a C-phase negative bus terminal 36 is welded on the C-phase negative bus copper foil 8.

[0076] In some embodiments, the A-phase upper bridge arm driving gate copper foil 12, the A-phase upper bridge arm driving source copper foil 13, the A-phase lower bridge arm driving gate copper foil 14, the A-phase lower bridge arm driving source copper foil 15, the B-phase upper bridge arm driving gate copper foil 16, the B-phase upper bridge arm driving source copper foil 17, the B-phase lower bridge arm driving gate copper foil 19, the B-phase lower bridge arm driving source copper foil 18, the C-phase upper bridge arm driving gate copper foil 21, the C-phase upper bridge arm driving source copper foil 20, the C-phase lower bridge arm driving gate copper foil 23 and the C-phase lower bridge arm driving source copper foil 22 are all "L"-shaped structures.

[0077] In some embodiments, Figure 4As shown, a copper foil layer 1-3 is provided on the back of the ceramic substrate 1-2; circular holes 1-4 with equal spacing are etched around the copper foil layer 1-3 along the edge of the ceramic substrate 1-2, and the back of the ceramic substrate 1-2 is directly connected to the heat sink through the copper foil layer 1-3 on its surface to improve the heat dissipation performance.

[0078] like Figure 5 As shown, the copper-clad ceramic substrate 1 is a three-layer structure, the upper and lower layers are both conductor layers, and the middle layer is a ceramic substrate 1-2. The upper conductor layer is etched to form a plurality of independent conductor layers, which together with the power chip, bonding wires, ceramic capacitors, terminals, etc. constitute the circuit topology. The ceramic substrate 1-2 of the middle layer plays an insulating and heat-conducting role. The copper foil layer 1-3 of the lower layer is generally connected to the heat sink through a thermal interface material to play a heat-conducting role. In this embodiment, the conductor layer is high-conductivity oxygen-free copper C1020, referred to as copper foil. The ceramic substrate 1-2 of the middle layer can generally be made of ceramic materials such as aluminum oxide, aluminum nitride, and silicon nitride. In this embodiment, in order to improve mechanical properties and reliability, the ceramic substrate 1-2 selects silicon nitride ceramics with the highest mechanical strength. The copper foil layer 1-3 of the lower layer is etched with a circle of circular holes on the edge of the lower copper foil at a certain distance from the edge, which helps to release the thermal stress of the edge of the copper foil and improve reliability.

[0079] The outer edges of the upper copper foil layer and the lower copper foil layer are at a certain distance from the edge of the ceramic substrate, which is determined according to the voltage resistance requirements of the module. In this embodiment, the outermost edge of the upper copper foil is set to be 1.8mm from the edge of the ceramic substrate, the outermost edge is set to be 1.7mm from the edge of the ceramic substrate, and the outermost edge of the lower copper foil is set to be 0.3mm from the edge of the ceramic substrate. The upper copper foil is processed to form a circuit pattern, which plays a role in conducting electricity and heat transfer.

[0080] The upper copper foil is composed of positive bus copper foil 5, A-phase negative bus copper foil 6, B-phase negative bus copper foil 7, C-phase negative bus copper foil 8, A-phase output copper foil 9, B-phase output copper foil 10, C-phase output copper foil 11, A-phase upper bridge arm driving gate copper foil 12, A-phase upper bridge arm driving source copper foil 13, A-phase lower bridge arm driving gate copper foil 14, A-phase lower bridge arm driving source copper foil 15, B-phase upper bridge arm driving gate copper foil 16, B-phase upper bridge arm driving source copper foil 17, B-phase lower bridge arm driving gate copper foil 18, B-phase lower bridge arm driving source copper foil 19, C-phase upper bridge arm driving gate copper foil 20, C-phase upper bridge arm driving source copper foil 21, C-phase lower bridge arm driving gate copper foil 22, and C-phase lower bridge arm driving source copper foil 23.

[0081] like Figure 6As shown, the low stray inductance three-phase full-bridge circuit corresponding to the packaging structure of the integrated ceramic capacitor three-phase full-bridge power module of this embodiment is composed of an A-phase bridge arm circuit 73, a B-phase bridge arm circuit 74 and a C-phase bridge arm circuit 75. The three-phase bridge arm circuits share the same positive bus. The A-phase bridge arm circuit 73 is composed of an A-phase upper bridge arm power chip 24 and an A-phase lower bridge arm power chip 25 connected in series and then connected in parallel with an A-phase ceramic capacitor 70. The B-phase bridge arm circuit 74 is composed of a B-phase upper bridge arm power chip 26 and a B-phase lower bridge arm power chip 27 connected in series and then connected in parallel with a B-phase ceramic capacitor 71. The C-phase bridge arm circuit 75 is composed of a C-phase upper bridge arm power chip 28 and a C-phase lower bridge arm power chip 29 connected in series and then connected in parallel with a C-phase ceramic capacitor 72.

[0082] Take the power loop PN of the A-phase bridge arm as an example: during commutation, the transient current flows from the positive end of the A-phase ceramic capacitor 70 into the positive bus copper foil 5, and then flows into the drain of the A-phase upper bridge arm power chip 24 through the positive bus copper foil 5, and then the transient current flows into the A-phase output copper foil 9 through the first power bonding wire 49 of the A-phase upper bridge arm power chip 24, and then the transient current flows into the drain of the A-phase lower bridge arm power chip 25 through the A-phase output copper foil 9, and then the transient current flows into the A-phase negative bus copper foil 6 through the second power bonding wire 50 of the A-phase lower bridge arm power chip 25, and finally, the transient current flows to the negative end of the A-phase ceramic capacitor 70 through the A-phase negative bus copper foil 6. In this embodiment, the path of the power commutation loop is limited by the integrated ceramic capacitor in the power module to the power chip-copper foil-bonding wire-ceramic capacitor, which realizes the decoupling of the internal power loop from the power terminal and the external wiring, and reduces the stray inductance of the power loop. Through finite element calculation, the stray inductance of the power module loop after the integrated decoupling capacitor is reduced by more than 80%, which suppresses the voltage spikes and oscillations during the commutation process and reduces electromagnetic interference noise.

[0083] In this embodiment, the power chip is welded by silver sintering, which can improve the thermal-mechanical properties of the power module, and the terminal is welded by ultrasonic welding, which can improve the welding strength.

[0084] In this embodiment, the bonding wire is selected from the aluminum bonding wire with low cost and the most application. In order to improve the flow capacity, in actual application, multiple bonding wires can be selected as much as possible according to the size of the bonding area on the chip. This embodiment makes full use of the source plating size of the power chip, and the power bonding wire is generally composed of multiple thick bonding wires in parallel; the power bonding wires (first power bonding wire 49, second power bonding wire 50, third power bonding wire 51, fourth power bonding wire 52, fifth power bonding wire 53, sixth power bonding wire 54) of this embodiment are each composed of 4 15mil diameter aluminum bonding wires in parallel. The Kelvin source bonding wires (first Kelvin source bonding wire 56, second Kelvin source bonding wire 58, third Kelvin source bonding wire 60, fourth Kelvin source bonding wire 62, fifth Kelvin source bonding wire 64, sixth Kelvin source bonding wire 66) are each composed of 1 aluminum bonding wire with a diameter of 15mil. Taking into account the small size of the chip gate, the driving gate bonding wires (the first driving gate bonding wire 55, the second driving gate bonding wire 57, the third driving gate bonding wire 59, the fourth driving gate bonding wire 61, the fifth driving gate bonding wire 63, and the sixth driving gate bonding wire 65) are each composed of an 8-mil diameter aluminum bonding wire.

[0085] In this embodiment, the drive signal connection of the power chips (A-phase upper bridge arm power chip 24, A-phase lower bridge arm power chip 25, B-phase upper bridge arm power chip 26, B-phase lower bridge arm power chip 27, C-phase upper bridge arm power chip 28, C-phase lower bridge arm power chip 29) all adopts the Kelvin structure: the source of the power chip is separately connected to a separate signal terminal by a bonding wire. This connection method can effectively reduce the common source inductance of the commutation circuit, reduce the coupling between the main power circuit and the drive circuit of the power chip, increase the switching speed, and thus reduce the switching loss.

[0086] The driving gate copper foil and Kelvin source copper foil of each bridge arm adopt an "L"-shaped structure.

[0087] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0088] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A packaging structure of a three-phase full-bridge power module with integrated ceramic capacitors, characterized in that: include: A ceramic substrate (1-2) and an A-phase bridge arm (2), a B-phase bridge arm (3) and a C-phase bridge arm (4) arranged on the front surface of the ceramic substrate (1-2); wherein the positive busbar copper foils (5) of the A-phase bridge arm (2), the B-phase bridge arm (3) and the C-phase bridge arm (4) are connected; The A-phase bridge arm (2) comprises: an A-phase upper bridge arm driving gate copper foil (12) and an A-phase upper bridge arm driving source copper foil (13) arranged above the left part of the positive bus copper foil (5), an A-phase negative bus copper foil (6) and an A-phase output copper foil (9) arranged below the left part of the positive bus copper foil (5), an A-phase lower bridge arm driving gate copper foil (14) and an A-phase lower bridge arm driving source copper foil (15) arranged directly below the A-phase output copper foil (9), an A-phase upper bridge arm power chip (24) arranged on the left part of the positive bus copper foil (5), an A-phase lower bridge arm power chip (25) arranged on the A-phase output copper foil (9), and an A-phase ceramic capacitor (70) arranged on the left part of the positive bus copper foil (5) and the A-phase negative bus copper foil (6); The B-phase bridge arm (3) comprises: a B-phase upper bridge arm driving gate copper foil (16) and a B-phase upper bridge arm driving source copper foil (17) arranged above the middle part of the positive bus copper foil (5), a B-phase negative bus copper foil (7) and a B-phase output copper foil (10) arranged below the middle part of the positive bus copper foil (5), a B-phase lower bridge arm driving gate copper foil (18) and a B-phase lower bridge arm driving source copper foil (19) arranged directly below the B-phase output copper foil (10), a B-phase upper bridge arm power chip (26) arranged on the middle part of the positive bus copper foil (5), a B-phase lower bridge arm power chip (27) arranged on the B-phase output copper foil (10), and a B-phase ceramic capacitor (71) arranged on the middle part of the positive bus copper foil (5) and the B-phase negative bus copper foil (7); The C-phase bridge arm (4) comprises: a C-phase upper bridge arm driving gate copper foil (20) and a C-phase upper bridge arm driving source copper foil (21) arranged above the right part of the positive bus copper foil (5), a C-phase negative bus copper foil (8) and a C-phase output copper foil (11) arranged below the right part of the positive bus copper foil (5), a C-phase lower bridge arm driving gate copper foil (22) and a C-phase lower bridge arm driving source copper foil (23) arranged directly below the C-phase output copper foil (11); a C-phase upper bridge arm power chip (28) arranged on the right part of the positive bus copper foil (5), a C-phase lower bridge arm power chip (29) arranged on the C-phase output copper foil (11), and a C-phase ceramic capacitor (72) arranged on the right part of the positive bus copper foil (5) and the C-phase negative bus copper foil (8); The left part of the positive bus copper foil (5), the A-phase output copper foil (9) and the A-phase negative bus copper foil (6) constitute the A-phase power circuit; the middle part of the positive bus copper foil (5), the B-phase output copper foil (10) and the B-phase negative bus copper foil (7) constitute the B-phase power circuit; the right part of the positive bus copper foil (5), the C-phase output copper foil (11) and the C-phase negative bus copper foil (8) constitute the C-phase power circuit; the layouts of the A-phase power circuit, the B-phase power circuit and the C-phase power circuit are the same; The position of the A-phase ceramic capacitor (70) in the A-phase power circuit, the position of the B-phase ceramic capacitor (71) in the B-phase power circuit, and the position of the C-phase ceramic capacitor (72) in the C-phase power circuit are the same.

2. The packaging structure of the three-phase full-bridge power module with integrated ceramic capacitor according to claim 1, characterized in that: The source of the A-phase upper bridge arm power chip (24) is connected to the A-phase output copper foil (9) via a first power bonding wire (49), the gate of the A-phase upper bridge arm power chip (24) is connected to the A-phase upper bridge arm drive gate copper foil (12) via a first drive gate bonding wire (55), and the source of the A-phase upper bridge arm power chip (24) is connected to the A-phase upper bridge arm drive source copper foil (13) via a first Kelvin source bonding wire (56); the A-phase lower bridge arm power chip (25) is connected to the A-phase negative busbar copper foil (6) via a second power bonding wire (50), the gate of the A-phase lower bridge arm power chip (25) is connected to the A-phase lower bridge arm drive gate copper foil (14) via a second drive gate bonding wire (57), and the source of the A-phase lower bridge arm power chip (25) is connected to the A-phase lower bridge arm drive source copper foil (15) via a second Kelvin source bonding wire (58).

3. The packaging structure of the three-phase full-bridge power module with integrated ceramic capacitor according to claim 1, characterized in that: The A-phase upper bridge arm driving gate copper foil (12) is welded with an A-phase upper bridge arm driving gate terminal (37), the A-phase upper bridge arm driving source copper foil (13) is welded with an A-phase upper bridge arm driving source terminal (38), the A-phase lower bridge arm driving gate copper foil (14) is welded with an A-phase lower bridge arm driving gate terminal (39), and the A-phase lower bridge arm driving source copper foil (15) is welded with an A-phase lower bridge arm driving source terminal (40).

4. The packaging structure of the three-phase full-bridge power module with integrated ceramic capacitor according to claim 1, characterized in that: The source of the B-phase upper bridge arm power chip (26) is connected to the B-phase output copper foil (10) through a third power bonding wire (51), the gate of the B-phase upper bridge arm power chip (26) is connected to the B-phase upper bridge arm drive gate copper foil (16) through a third drive gate bonding wire (59), and the source of the B-phase upper bridge arm power chip (26) is connected to the B-phase upper bridge arm drive source copper foil (17) through a third Kelvin source bonding wire (60); the B-phase lower bridge arm power chip (27) is connected to the B-phase negative busbar copper foil (7) through a fourth power bonding wire (52), the gate of the B-phase lower bridge arm power chip (27) is connected to the B-phase upper bridge arm drive gate copper foil (18) through a fourth drive gate bonding wire (61), and the source of the B-phase lower bridge arm power chip (27) is connected to the B-phase lower bridge arm drive source copper foil (19) through a fourth Kelvin source bonding wire (62).

5. The packaging structure of the three-phase full-bridge power module with integrated ceramic capacitors according to claim 1, characterized in that: The B-phase upper bridge arm driving gate copper foil (16) is welded with a B-phase upper bridge arm driving gate terminal (41), the B-phase upper bridge arm driving source copper foil (17) is welded with a B-phase upper bridge arm driving source terminal (42), the B-phase lower bridge arm driving gate copper foil (18) is welded with a B-phase lower bridge arm driving gate terminal (43), and the B-phase lower bridge arm driving source copper foil (19) is welded with a B-phase lower bridge arm driving source terminal (44).

6. The packaging structure of the three-phase full-bridge power module with integrated ceramic capacitors according to claim 1, characterized in that: The source of the C-phase upper bridge arm power chip (28) is connected to the C-phase output copper foil (11) through a fifth power bonding wire (53), the gate of the C-phase upper bridge arm power chip (28) is connected to the C-phase upper bridge arm drive gate copper foil (20) through a fifth drive gate bonding wire (63), and the source of the C-phase upper bridge arm power chip (28) is connected to the C-phase upper bridge arm drive source copper foil (21) through a fifth Kelvin source bonding wire (64); the C-phase lower bridge arm power chip (29) is connected to the C-phase negative busbar copper foil (8) through a sixth power bonding wire (54), the gate of the C-phase lower bridge arm power chip (29) is connected to the C-phase upper bridge arm drive gate copper foil (22) through a sixth drive gate bonding wire (65), and the source of the C-phase lower bridge arm power chip (29) is connected to the C-phase lower bridge arm drive source copper foil (23) through a sixth Kelvin source bonding wire (66).

7. The packaging structure of the three-phase full-bridge power module with integrated ceramic capacitors according to claim 1, characterized in that: The C-phase upper bridge arm driving gate copper foil (20) is welded with a C-phase upper bridge arm driving gate terminal (45), the C-phase upper bridge arm driving source copper foil (21) is welded with a C-phase upper bridge arm driving source terminal (46), the C-phase lower bridge arm driving gate copper foil (22) is welded with a C-phase lower bridge arm driving gate terminal (47), and the C-phase lower bridge arm driving source copper foil (23) is welded with a C-phase lower bridge arm driving source terminal (48).

8. The packaging structure of the three-phase full-bridge power module with integrated ceramic capacitors according to claim 1, characterized in that: A first positive busbar terminal (30a) is arranged above the A-phase ceramic capacitor (70) on the positive busbar copper foil (5), a source bonding wire (30b) is arranged above the B-phase ceramic capacitor (71) on the positive busbar copper foil (5), and a third positive busbar terminal (30c) is arranged above the C-phase ceramic capacitor (72) on the positive busbar copper foil (5); an A-phase output terminal (31) is welded to the A-phase output copper foil (9), a B-phase output terminal (32) is welded to the B-phase output copper foil (10), and a C-phase output terminal (33) is welded to the C-phase output copper foil (11); an A-phase negative busbar terminal (34) is welded to the A-phase negative busbar copper foil (6), a B-phase negative busbar terminal (35) is welded to the B-phase negative busbar copper foil (7), and a C-phase negative busbar terminal (36) is welded to the C-phase negative busbar copper foil (8).

9. The packaging structure of the three-phase full-bridge power module with integrated ceramic capacitors according to claim 1, characterized in that: A first solder resist layer (67) is disposed below the A-phase ceramic capacitor (70); a second solder resist layer (68) is disposed below the B-phase ceramic capacitor (71); and a third solder resist layer (69) is disposed below the C-phase ceramic capacitor (72).

10. The packaging structure of the three-phase full-bridge power module with integrated ceramic capacitors according to claim 1, characterized in that: A copper foil layer (1-3) is arranged on the back of the ceramic substrate (1-2); and circular holes (1-4) with equal spacing are etched around the copper foil layer (1-3) along the edge of the ceramic substrate (1-2).

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