CN220233181U - Power module - Google Patents

Abstract

The application provides a power module, including the substrate base plate, the first power chip on first metal level surface in the substrate base plate and the second power chip on second metal level surface, first electrically conductive cushion, the second electrically conductive cushion on second power chip surface, the first electrically conductive base plate on first power chip surface, first electrically conductive cushion passes through electric connection structure and the fourth metal level electricity in the second electrically conductive base plate is connected, first metal level connects DC+ terminal, the fourth metal level connects DC-terminal, current signal is input through first metal level, flow through first power chip in proper order, the third metal level, first electrically conductive cushion, the second metal level, the second power chip, the electrically conductive cushion, electric connection structure, finally export through the fourth metal level, realize the folding of power return circuit, make the power return circuit have very high overlap nature, and then effectively reduce the stray inductance of power return circuit, with the very low stray inductance of realization power return circuit, thereby can promote the comprehensive properties of power module.

Description

Power module

Technical Field

The application relates to the technical field of power semiconductor packaging, in particular to a power module.

Background

In various power systems, such as automobile motor drivers, direct current step-up and step-down systems, photovoltaic inverter systems, etc., various power semiconductor devices are widely used. The power module assembles a plurality of or a plurality of groups of power semiconductor chips and forms a required circuit topological structure, has the advantages of better heat dissipation, excellent electrical characteristics and the like, and can also improve the integration level of the system and reduce the subsequent assembly complexity. Therefore, the power module is a power semiconductor product commonly used in a high-power electronic power system, and the performance of the power module has a great influence on the high-power electronic power system.

For the power module, the stray inductance of the power loop is one of important performance indexes, and the lower stray inductance can improve the comprehensive performance of the power module so as to improve the performance of a high-power electronic power system. Therefore, providing a power module with low stray inductance is an important issue for those skilled in the art.

Disclosure of Invention

In view of this, the present application provides a power module, which has the following scheme:

a power module, the power module comprising:

the substrate comprises a first insulating layer, a first metal layer and a second metal layer, wherein the first metal layer and the second metal layer are positioned on the surface of the first insulating layer;

At least one first power chip and at least one second power chip, the at least one first power chip being located on the surface of the first metal layer in electrical contact with the first metal layer, the at least one second power chip being located on the surface of the second metal layer in electrical contact with the second metal layer;

the first conductive substrate comprises a third metal layer, a second insulating layer and a fourth metal layer which are sequentially stacked along one side away from the surface of the first insulating layer, wherein the third metal layer is in electrical contact with the surface of the first power chip, the surface of the second metal layer is also provided with a first conductive cushion block, and the third metal layer is also in electrical contact with the surface of the first conductive cushion block;

the second conductive cushion blocks are in one-to-one correspondence with the second power chips, are positioned on the surfaces of the second power chips and are in electrical contact with the second power chips, and are also electrically connected with the fourth metal layer through the electrical connection structures;

the first metal layer is electrically connected with the DC+ terminal, the second metal layer is electrically connected with the AC terminal, the fourth metal layer is electrically connected with the DC-terminal, and current signals are input through the first metal layer and output through the fourth metal layer.

Optionally, the electrical connection structure is a first conductive connection piece, and the first conductive connection piece is located on the surface of the at least one second conductive pad and is in electrical contact with the at least one second conductive pad, and is also located on the surface of the fourth metal layer and is in electrical contact with the fourth metal layer, so as to electrically connect the second conductive pad and the fourth metal layer.

Optionally, the electrical connection structure is at least one first bonding wire, the first bonding wire corresponds to the second conductive cushion block one by one, one end of the first bonding wire is electrically connected with the second conductive cushion block, and the other end of the first bonding wire is electrically connected with the fourth metal layer.

Optionally, the power module further includes: the at least one third conductive cushion block is in one-to-one correspondence with the at least one first power chip, is positioned on the surface of the first power chip and is in electrical contact with the first power chip, is also in electrical contact with the third metal layer, and is electrically connected with the first power chip and the third metal layer.

Optionally, the power module includes a plurality of first power chips and a plurality of second power chips, wherein the plurality of first power chips are arranged in an array on the surface of the first metal layer, and the plurality of second power chips are arranged in an array on the surface of the second metal layer.

Optionally, the substrate further includes a fifth metal layer located on the back surface of the first insulating layer, where the fifth metal layer covers the back surface of the first insulating layer, and the back surface of the first insulating layer is opposite to the surface of the first insulating layer.

Optionally, the electrical connection structure is a second conductive substrate, and the second conductive substrate includes a sixth metal layer, a third insulating layer, and a seventh metal layer sequentially stacked along a side facing away from the surface of the first insulating layer, where the sixth metal layer covers the surface of the second conductive pad and the surface of the fourth metal layer, and extends at least to an edge of the fourth metal layer along a first direction;

the first direction is parallel to the arrangement direction of the second power chip and the first power chip.

Optionally, the power module further includes: the second conductive connecting sheet, the fourth conductive cushion block and the eighth metal layer are positioned on the surface of the first insulating layer;

the fourth conductive cushion block is located on the surface of the eighth metal layer and is in electrical contact with the eighth metal layer, the second conductive connecting sheet is located on the surface of the fourth metal layer and the surface of the fourth conductive cushion block, the fourth metal layer is electrically connected with the eighth metal layer, and the eighth metal layer is electrically connected with the DC-terminal.

Optionally, the dc+ terminal, the DC-terminal and the AC terminal are copper bar terminals, where the DC-terminal and the dc+ terminal are sequentially arranged along a second direction and at least partially overlap in a first direction, the first direction is parallel to an arrangement direction of the second power chip and the first power chip, and the second direction is perpendicular to a surface of the first insulating layer;

the power chip further includes: the second bonding wire is electrically connected with the DC+ terminal and the first metal layer, the third bonding wire is electrically connected with the DC-terminal and the fourth metal layer, and the fourth bonding wire is electrically connected with the second metal layer and the AC terminal.

Optionally, the dc+ terminal, the DC-terminal, and the AC terminal are copper bar terminals, the dc+ terminal is in electrical contact with the first metal layer, the DC-terminal is in electrical contact with the fourth metal layer, and the AC terminal is in electrical contact with the second metal layer;

the DC-terminals and the DC+ terminals are sequentially arranged along a second direction and at least partially overlap in a first direction, the first direction is parallel to the arrangement direction of the second power chip and the first power chip, and the second direction is perpendicular to the surface of the first insulating layer.

Compared with the prior art, the beneficial effects of the technical scheme are as follows:

the power module provided by the application comprises: the substrate comprises a first power chip positioned on the surface of a first metal layer of the substrate, a second power chip positioned on the surface of a second metal layer of the substrate, a first conductive cushion block positioned on the surface of the second metal layer, and a second conductive cushion block positioned on the surface of the second power chip, wherein the first conductive substrate comprises a third metal layer, a second insulating layer and a fourth metal layer which are sequentially laminated, the second conductive cushion block is electrically connected with the fourth metal layer through an electric connection structure, the first metal layer, the first power chip, the third metal layer, the first conductive cushion block, the second metal layer, the second power chip, the second conductive cushion block, the electric connection structure and the fourth metal layer are sequentially electrically connected, the first metal layer is electrically connected with a DC+ terminal, the fourth metal layer is electrically connected with a DC-terminal, the DC+ terminal is a signal input port, and the DC-terminal is a signal output port. Therefore, in the power module, a current signal can be input through the first metal layer and sequentially flows through the first metal layer, the first power chip, the third metal layer, the first conductive cushion block, the second metal layer, the second power chip, the second conductive cushion block, the electric connection structure and the fourth metal layer, and finally, the power loop of the power module is output through the fourth metal layer, so that the power loop of the power module provided by the application has very high overlapping performance, and the transmission directions of currents in the overlapping loops are opposite, therefore, the stray inductance of the power loop of the power module can be effectively reduced, the extremely low stray inductance of the power loop is realized, and the comprehensive performance of the power module can be improved.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the related art, the drawings that are required to be used in the embodiments or the description of the prior art will be briefly described below, and it is apparent that the drawings in the following description are only embodiments of the present application, and other drawings may be obtained according to the provided drawings without inventive effort to those skilled in the art.

The structures, proportions, sizes, etc. shown in the drawings are shown only in connection with the present disclosure, and should not be construed as limiting the scope of the invention, since any modification, variation in proportions, or adjustment of the size, which would otherwise be used by those skilled in the art, would not have the essential significance of the present disclosure, would not affect the efficacy or otherwise be achieved, and would still fall within the scope of the present disclosure.

Fig. 1 is a schematic structural diagram of a power module provided in the present application;

FIG. 2 is a cross-sectional view taken along AA1 of FIG. 1;

FIG. 3 is a schematic diagram of a power chip;

FIG. 4 is a schematic diagram of an electrical topology of a conventional power module and a schematic diagram of a power loop;

Fig. 5 is a schematic diagram of a power loop of a power module provided in the present application;

fig. 6 is a schematic structural diagram of another power module provided in the present application;

fig. 7 is a schematic structural diagram of another power module provided in the present application;

fig. 8 is a schematic layout diagram of a first power chip and a second power chip in a power module provided in the present application;

FIG. 9 is a schematic diagram of another power module provided in the present application;

fig. 10 is a schematic structural diagram of another power module provided in the present application;

FIG. 11 is a schematic diagram of a power module according to another embodiment of the present disclosure;

fig. 12 is a schematic diagram of connection between a power module and an external terminal provided in the present application;

fig. 13 is a schematic diagram of connection between another power module and an external terminal according to the present application.

Detailed Description

Embodiments of the present application will now be described more fully hereinafter with reference to the accompanying drawings, in which it is shown, and in which it is evident that the embodiments described are exemplary only of one area of the application, and not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.

In order that the above-recited objects, features and advantages of the present application will become more readily apparent, a more particular description of the invention briefly described above will be rendered by reference to specific embodiments that are illustrated in the appended drawings.

Semiconductor power modules are a type of power semiconductor product commonly used in electronic power systems, and generally include: the power semiconductor chip, the insulating substrate, the supporting bottom plate, the shell, the connecting terminals, the bonding wires, the encapsulating material and the like realize the required circuit topology through the circuit patterns, the bonding wires and the connecting terminals on the insulating substrate.

The performance of the semiconductor power module has a larger influence on the electronic power system, wherein the stray inductance is one of important performance indexes of the power module, and the lower stray inductance can reduce voltage spikes in the switching-on and switching-off process, inhibit voltage and current waveform oscillation and reduce switching loss, so that the comprehensive performance of the power module is improved, and the performance of the electronic power system is improved.

The prior technical scheme for reducing parasitic inductance of the power module comprises the following steps: 1. adopting a copper sheet to replace a bonding wire; 2. a flexible circuit board is used instead of a bond wire, etc. For method 1, the effect of reducing stray inductance of the bonding wire is limited by adopting a copper sheet instead of the bonding wire. For the method 2, the flexible circuit board is adopted to replace the bonding wire scheme, so that the requirements on the flexible circuit board are high, suitable materials are not easy to find, the cost is high, the current carrying capacity of the flexible circuit board is limited, and the application of the power module in a high-power electronic power system is limited.

Based on this, the present application provides a power module, as shown in fig. 1 and 2, fig. 2 is a cross-sectional view along AA1 of fig. 1, the power module including:

a substrate 100, the substrate 100 including a first insulating layer 101 and a first metal layer 102 and a second metal layer 103 on a surface of the first insulating layer 101; wherein the first insulating layer 101 is a ceramic insulating layer, and the first metal layer 102 and the second metal layer 103 are conductive metal layers with conductive functions; it should be noted that, the first metal layer 102 and the second metal layer 103 are metal layers patterned by an etching process, so as to implement electrical topology and corresponding insulation requirements, and the first metal layer 102 and the second metal layer 103 are electrically insulated.

At least one first power chip 110 and at least one second power chip 120, the at least one first power chip 110 being located on the surface of the first metal layer 102 and being in electrical contact with the first metal layer 102, i.e. the first power chip is electrically connected to the first metal layer 102; the at least one second power chip 120 is located on the surface of the second metal layer 103 and is in electrical contact with the second metal layer 103, i.e. the second power chip 120 is electrically connected with the second metal layer 103; it should be noted that, the first power chip 110 and the second power chip 120 may be MOSFETs, IGBT chips, etc., which are not limited in this application, and are specific as the case may be; when the power chip is a MOSFET chip, as shown in fig. 3, fig. 3 is a schematic structural diagram of the power chip, one side of the first power chip 110 connected to the first metal layer 102 is a drain D, the opposite side is a source S, one side of the second power chip 120 connected to the second metal layer 103 is a drain D, the opposite side is a source S, that is, the upper and lower surfaces of the first power chip 110 are the source S and the drain D, the upper and lower surfaces of the second power chip 120 are the source S and the drain D, respectively, and the first power chip 110 and the second power chip 120 further include a gate G.

The first conductive substrate 130, the first conductive substrate 130 includes a third metal layer 131, a second insulating layer 132 and a fourth metal layer 133 sequentially stacked along a side facing away from the surface of the first insulating layer 101, that is, the first conductive substrate 130 includes, from bottom to top, the third metal layer 131, the second insulating layer 132 covering the surface of the first metal layer 131, and the fourth metal layer 133 covering the surface of the second insulating layer 132; the third metal layer 131 is in electrical contact with the first power chip 110, i.e., the third metal layer 131 is located on the surface of the first power chip and is electrically connected with the first power chip 110; the surface of the second metal layer 103 is also provided with a first conductive pad 141, that is, the power module further comprises a first conductive pad 141 which is positioned on the surface of the second metal layer 103 and is electrically contacted with the second metal layer 103, the third metal layer 131 is also electrically contacted with the first conductive pad 141, that is, the third metal layer 131 is also positioned on the surface of the first conductive pad 141 and is electrically connected with the first conductive pad 141, that is, the third metal layer 131 in the first conductive substrate 130 is electrically connected with the first power chip 110 and is also electrically connected with the first conductive pad 141, so that the first power chip 110 and the first conductive pad 141 are electrically connected through the third metal layer 131; it should be noted that, when the power module includes a plurality of first power chips 110, the third metal layer 131 is located on the surfaces of the plurality of first power chips 110 and is electrically contacted with the plurality of first power chips 110; it should be noted that, in order to reduce the assembly difficulty of the power module, the surface of the first conductive pad 141 and the surface of the first power chip 110 are at the same height, i.e., the surface of the first conductive pad 141 and the surface of the first power chip 110 are located at the same plane.

At least one second conductive pad 142 and an electrical connection structure, the second conductive pad 142 is in one-to-one correspondence with the second power chip 120, and is located on the surface of the second power chip 120 and is in electrical contact with the second power chip 120, i.e. the second conductive pad 142 is located on the surface of the second power chip 120 and is electrically connected with the second power chip 120, and the second conductive pad 142 is also electrically connected with the fourth metal layer 133, i.e. the second conductive pad 142 is electrically connected with the second power chip 120, and the second conductive pad 142 is also electrically connected with the fourth metal layer 133 through the electrical connection structure, so that the second power chip 120 can be electrically connected with the fourth metal layer 133.

Wherein the first metal layer 102 is electrically connected to the dc+ terminal, the second metal layer 103 is electrically connected to the AC terminal, the fourth metal layer 133 is electrically connected to the DC-terminal, and a current signal is input through the first metal layer 103 and output through the fourth metal layer 133. For simplicity of illustration, control terminals such as gates and the like are omitted from fig. 1 and 2, and only portions related to the power circuit are shown.

Specifically, in the embodiment of the present application, as can be seen from the above description, the first metal layer 102 is electrically connected to the first power chip 110, the first power chip 110 is electrically connected to the first conductive pad 141 through the third metal layer 131, the first conductive pad 141 is located on the surface of the second metal layer 103 and is electrically connected to the second metal layer 103, and the second power chip 120 is also located on the surface of the second metal layer 103 and is electrically connected to the second metal layer 103, that is, the first conductive pad 141 is electrically connected to the second power chip 120 through the second metal layer 103. Meanwhile, the surface of the second power chip 120 is further provided with a second conductive pad 142 electrically connected with the second power chip, and the second conductive pad 142 is further electrically connected with the fourth metal layer 133 through an electrical connection structure. Therefore, in the power module provided in the present application, the first metal layer 102, the first power chip 110, the third metal layer 131, the first conductive pad 141, the second metal layer 103, the second power chip 120, the second conductive pad 142, the electrical connection structure, and the fourth metal layer 133 are electrically connected in sequence.

And in the power module, the first metal layer 102 is electrically connected to the dc+ terminal, and the fourth metal layer 133 is electrically connected to the DC-terminal, wherein the dc+ terminal is a signal input port and the DC-terminal is a signal output port, so that in the power module, a current signal is input through the first metal layer 102 and finally output through the fourth metal layer 133. Based on the above-mentioned known, in the power module, the first metal layer 102, the first power chip 110, the third metal layer 131, the first conductive pad 141, the second metal layer 103, the second power chip 120, the second conductive pad 142, the electrical connection structure, and the fourth metal layer 133 are electrically connected successively, so that after the current signal is input through the first metal layer 102, the current signal flows through the first power chip 110, the third metal layer 131, the first conductive pad 141, the second metal layer 103, the second power chip 120, the second conductive pad 142, and the electrical connection structure in sequence, and finally is output through the fourth metal layer 133, the power circuit is folded, so that the power circuit of the power module provided by the application has very high overlapping property, and the transmission directions of currents in the overlapping circuits are opposite, therefore, the stray inductance of the power circuit of the power module can be effectively reduced, the stray inductance of the power circuit is extremely low, and the comprehensive performance of the power module is improved.

As shown in fig. 4 and fig. 5, fig. 4 is an electrical topology diagram and a power circuit diagram of an existing power module, in fig. 4, a dc+ terminal is connected to a drain electrode of an upper bridge power chip S1, an AC terminal is connected to a source electrode of the upper bridge chip S1 and a drain electrode of a lower bridge chip S2, a DC-terminal is connected to a source electrode of the lower bridge chip S2, a dotted line represents the power circuit, and a current signal flows in from the dc+ terminal and flows out from the DC-terminal; fig. 5 is a schematic diagram of a power loop of the power module provided by the application, and comparing fig. 4 and fig. 5, it can be known that the power loop of the power module provided by the application has high overlapping property, and the transmission directions of currents in the overlapping loops are opposite, so that the stray inductance of the power loop of the power module can be effectively reduced, the extremely low stray inductance of the power loop is realized, and the comprehensive performance of the power module can be improved.

On the basis of the above embodiment, in one embodiment of the present application, as further shown in fig. 1 and 2, the above electrical connection structure is a first conductive connection piece 151, where the first conductive connection piece 151 is located on a surface of at least one second conductive pad 142 and is electrically connected to at least one second conductive pad 142, that is, the first conductive connection piece 151 is located on a surface of at least one second conductive pad 142 and is electrically connected to at least one conductive pad 142, and the first conductive connection piece 151 is also located on a surface of the fourth metal layer 133 and is electrically connected to the fourth metal layer 133, that is, the first conductive connection piece 151 is also located on a surface of the fourth metal layer 133 and is electrically connected to the fourth metal layer 133, so that the first conductive connection piece 151 is electrically connected to the second conductive pad 142 and the fourth metal layer 133, that is, the second conductive pad 142 and the fourth metal layer 133 are electrically connected through the first conductive connection piece 151, and electrical conduction between the second conductive pad 142 and the fourth metal layer 133 is achieved. It should be noted that, the first conductive connection piece 151 being located on the surface of at least one second conductive pad and being in electrical contact with at least one second conductive pad means that, when the power module includes one second conductive pad 142, that is, includes one second power chip 120, the first conductive connection piece 151 is located on the surface of the one second conductive pad and is in electrical contact with the surface of the one second conductive pad; when the power module includes a plurality of second conductive pads 142, that is, includes a plurality of second power chips 120, the first conductive tabs 151 are simultaneously located on the surfaces of the plurality of second conductive pads and electrically contact the plurality of second conductive pads. It should be noted that, in the present embodiment, in order to facilitate assembly of the power module, the surface of the second conductive pad 142 and the surface of the fourth metal layer 133 are on the same height, i.e. the surface of the second conductive pad 142 and the surface of the fourth metal layer 133 are on the same plane;

In another embodiment of the present application, as shown in fig. 6, the above-mentioned electrical connection structure is at least one first bonding wire 161, at least one first bonding wire 161 and at least one second conductive pad 142 are in one-to-one correspondence, and one end of the first bonding wire 161 is electrically connected with the second conductive pad 142, the other end is electrically connected with the fourth metal layer 133, and two ends of the first bonding wire 161 are respectively bonded to surfaces of the second conductive pad 142 and the fourth metal layer 133, so as to electrically connect the second conductive pad 142 and the fourth metal layer 133, thereby realizing electrical conduction between the second conductive pad 142 and the fourth metal layer 133. In this embodiment, the second conductive pad 142 and the fourth metal layer 133 are electrically connected by a wire bonding process, so that the assembly process of the power module can be simplified. And the surface of the second conductive pad block 142 and the surface of the fourth metal layer 133 are not required to be at the same height, so that the size matching difficulty between the parts in the power module assembling process is reduced, and the power module assembling process is simplified.

On the basis of any of the above embodiments, in one embodiment of the present application, as shown in fig. 7, the power module further includes: the at least one third conductive pad 143 corresponds to the at least one first power chip 110 one by one, the surface of the first power chip 110 is in electrical contact with the first power chip 110, that is, the third conductive pad 143 is positioned on the surface of the first power chip 110 and is electrically connected with the first power chip 110, and the third conductive pad 143 is also in electrical contact with the third metal layer 131, that is, the third conductive pad 143 is also electrically connected with the third metal layer 131, so that the first power chip 110 is electrically connected with the third metal layer 131 through the third conductive pad 143, the third metal layer 131 covering the first power chip 110 is prevented from being welded directly on the surface of the first power chip 110, the electrical conduction between the first power chip 110 and the third metal layer 131 is realized through welding the third conductive pad 143 with smaller size on the surface of the first power chip 110, the damage to the first power chip 110 caused by welding the third metal layer 131 is avoided, the welding reliability of the first power chip 110 is ensured, and the reliability of the power module is ensured. It should be noted that, when the power chip includes a third conductive pad 143, that is, includes a first power chip 110, the third metal layer 131 is in electrical contact with a third conductive pad 143; when the power chip includes a plurality of third conductive pads 143, i.e., includes a plurality of first power chips 110, the third metal layer 131 is simultaneously in electrical contact with the plurality of third conductive pads 143.

Based on the above embodiments, in one embodiment of the present application, as shown in fig. 8 and fig. 9, fig. 8 is a schematic distribution diagram of a plurality of first power chips 110 and a plurality of second power chips 120, and fig. 9 is a schematic structure diagram of a power module provided in the present application, where the power module includes a plurality of parallel first power chips 110 and a plurality of parallel second power chips 120, where the plurality of first power chips 110 are arranged in an array on a surface of the first metal layer 102, the plurality of second power chips 120 are arranged in an array on a surface of the second metal layer 103, so that each parallel first power chip 110 is symmetrically distributed, each parallel second power chip 120 is symmetrically distributed, so that each parallel first power chip 110 and each parallel second power chip 120 are symmetrical with respect to a position of the first metal layer 102, the second metal layer 103 and the fourth metal layer 133, and each parallel first power chip 110 and each parallel second power chip 120 are symmetrical with respect to a connection position of a terminal, which helps to reduce a difference between the parallel first power chips 110 and the terminal and the power module has good current sharing characteristics when the parallel power chips and the distance between the parallel power chips and the second power chips are reduced. It should be noted that, when the power module includes the plurality of first power chips 110 and the plurality of second power chips 120, the drains of the plurality of first power chips 110 are all in electrical contact with the first metal layer 102, the sources are all in electrical contact with the third metal layer 131, the current signals flow through the first metal layer 102, all flow out through the third metal layer 131, the drains of the plurality of second power chips 120 are all in electrical contact with the second metal layer 103, the sources are all in electrical contact with the fourth metal layer 133, the current signals flow in through the second metal layer 103, all flow out through the fourth metal layer 133, and therefore, the plurality of first power chips 110 have the same input and output ends, the plurality of second power chips 120 also have the same input and output ends, so that the plurality of first power chips 110 are in a parallel state, and the plurality of second power chips 120 are in a parallel state.

It should be noted that, when the power module includes a plurality of first power chips 110 and a plurality of second power chips 120, the chip types of the plurality of first power chips 110 may be the same or different, and the chip types of the plurality of second power chips 120 may be the same or different. For example, the plurality of first power chips 110 include IGBT chips and anti-parallel diode FRD chips, and the plurality of second power chips 120 include IGBT chips and anti-parallel diode FRD chips. It should be noted that, when the first power chip 110 and the second power chip 120 include the two chips, the distribution of the two power chips on the first metal layer 102 and the second metal layer 103 is optional, which is not limited in this application.

On the basis of any of the above embodiments, in one embodiment of the present application, as shown in fig. 2, the substrate board 100 further includes a fifth metal layer 104 located on the back surface of the first insulating layer 101, where the fifth metal layer 104 covers the back surface of the first insulating layer 101, and the back surface of the first insulating layer 101 is opposite to the surface of the first insulating layer 101. Because the metal has better heat conduction capability, the fifth metal layer 104 is located at the lowest layer, i.e. the outermost layer, of the power module, so that the fifth metal layer 104 can be used as a power radiating surface, and the fifth metal layer 104 is located at the back of the first insulating layer 101, so that the electric insulation of the radiating surface is realized, and the radiating surface of the power module can be directly attached or welded on a radiating device, such as a radiating plate, to perform efficient heat dissipation, and further realize efficient heat dissipation of the power module.

Based on the above embodiment, in one embodiment of the present application, as shown in fig. 10, the above electrical connection structure is a second conductive substrate 170, where the second conductive substrate 170 includes a sixth metal layer 171, a third insulating layer 172, and a seventh metal layer 173 that are sequentially stacked along a side facing away from the surface of the first insulating layer 101, where the sixth metal layer 171 covers the surface of the second metal layer pad 142 and the surface of the fourth metal layer 133 and extends at least to the edge of the fourth metal layer 133 along a first direction, and the first direction is parallel to the arrangement direction of the second power chip 110 and the first power chip 120. In the present embodiment, the sixth metal layer 171 covers the surface of the second metal layer pad 142 and the surface of the fourth metal layer 133, so as to achieve electrical conduction between the second metal pad 142 and the fourth metal layer 133. In addition, the seventh metal layer 173 is located at the uppermost layer, i.e. the outermost layer, of the power module, and extends at least to the edge of the fourth metal layer 133 along the arrangement direction of the first power chip 110 and the second power chip 120, and may be used as a heat dissipation surface of the power module, and the seventh metal layer 173 is located at the back surface of the third insulating layer 172, so that electrical insulation of the heat dissipation surface is achieved, and the heat dissipation surface of the power module may be directly attached or welded to a heat dissipation device, such as a heat dissipation plate, to perform efficient heat dissipation, thereby achieving efficient heat dissipation of the power module.

In addition, the power module provided by the application comprises the fifth metal layer 104 positioned at the lowest layer and the seventh metal layer 173 positioned at the uppermost layer, so that the power module is provided with an upper radiating surface and a lower radiating surface, and double-sided heat dissipation can be performed on the power module, and further high-efficiency heat dissipation of the power module is realized.

Alternatively, in one embodiment of the present application, the substrate 100, the first conductive substrate 130 and the second conductive substrate 170 are each formed by combining an electrically insulating intermediate ceramic layer and an upper metal layer and a lower metal layer having a conductive function, and are preferably an alumina direct bonding copper-clad ceramic substrate, a silicon nitride active metal brazing ceramic substrate, or the like, and may also be a ceramic aluminum-clad substrate, an insulating metal substrate, or the like. However, the present application is not limited thereto, and the present application is not limited thereto as the case may be.

Based on the above embodiments, in one embodiment of the present application, as shown in fig. 11, the power module further includes: the second conductive connecting piece 152 and the fourth conductive pad 144, and the eighth metal layer 105 located on the surface of the first insulating layer 101; the fourth conductive pad 144 is located on the surface of the eighth metal layer 105 and electrically contacts with the eighth metal layer 105, that is, the fourth conductive pad 144 is located on the surface of the eighth metal layer 105 and electrically connected with the eighth metal layer 105, the second conductive connecting piece 152 is located on the surface of the fourth metal layer 133 and the surface of the fourth conductive pad 144, electrically connects the fourth metal layer 133 and the eighth metal layer 105, and the eighth metal layer 105 is connected with the DC-terminal, that is, the fourth metal layer 133 is electrically connected with the DC-terminal through the eighth metal layer 105. It can be seen that in this embodiment, the area for directly and electrically connecting the DC-terminals is added in the surface metal layer of the first insulating layer 101, that is, the external terminals are all electrically connected with the metal layer located on the surface of the first insulating layer 101 in the power module, so that the power module is electrically connected with the external terminals, and the reliability of the electrical connection between the power module and the external terminals can be ensured.

Note that, the connection manner between the second connection pad 162 and the fourth conductive pad 144 and the connection manner between the fourth metal layer 133 and the eighth metal layer 105 may be a soldering manner such as reflow soldering, conductive silver paste, micro-nano material (silver, copper) sintering, and the like. The present application is not limited thereto, and is specific as the case may be. In other embodiments of the present application, instead of soldering, a wire bonding process may be used, for example, using thick aluminum wires, aluminum strips, copper wires, etc. to connect the second connection pads 162 and the fourth conductive pads 144 and the fourth metal layer 133 and the eighth metal layer 105. Note that the eighth metal layer 105 and the first insulating layer 101 are connected in the same manner as the first metal layer 102 and the second metal layer 103 are connected to the first insulating layer 101.

The external terminals may be connected to the power module by other means than electrically connecting the external terminals to the metal layer on the surface of the first insulating layer 101 in the power module. In one embodiment of the present application, as shown in fig. 12, the dc+ terminals, the DC-terminals and the AC terminals are copper bar terminals, where the DC-terminals and the dc+ terminals are sequentially arranged along a second direction, and at least partially overlap in the first direction, and the second direction is perpendicular to the surface of the first insulating layer 101; the power chip further includes: a second bonding wire 162, a third bonding wire 163, and a fourth bonding wire 164, the second bonding wire 162 electrically connecting the dc+ terminal and the first metal layer 102, the third bonding wire 163 electrically connecting the DC-terminal and the fourth metal layer 133, and the fourth bonding wire 164 electrically connecting the second metal layer 103 and the AC terminal. Therefore, the power module is electrically connected with the external terminal through a wire bonding process, and the process is simple and easy to realize. And the DC-terminal and the DC+ terminal are sequentially arranged along the second direction and at least partially overlap in the first direction, namely when the connection mode is adopted, the DC-terminal and the DC+ terminal are also of a laminated structure, so that the signal input and output port and the signal output port of the power module are of the laminated structure, the overlapping performance of a power loop is further enhanced, the realization of extremely low stray inductance of the power loop is facilitated, and the performance of the power module is improved.

In another embodiment of the present application, as shown in fig. 13, the dc+ terminal, the DC-terminal, and the AC terminal are copper bar terminals, the dc+ terminal is in electrical contact with the first metal layer 102, the DC-terminal is in electrical contact with the fourth metal layer 133, and the AC terminal is in electrical contact with the second metal layer 103; the DC-terminals and the dc+ terminals are sequentially arranged along a second direction and at least partially overlap in a first direction, the first direction is parallel to the arrangement direction of the second power chip and the first power chip, and the second direction is perpendicular to the surface of the first insulating layer 101. Therefore, the dc+ terminal is directly welded on the first metal layer 102, the DC-terminal is directly welded on the fourth metal layer 133, the AC terminal is directly welded on the second metal layer 103, and the DC-terminal and the dc+ terminal are sequentially arranged along the second direction and at least partially overlapped in the first direction, so that the signal input/output port and the signal output port of the power module are in a laminated structure, the overlapping property of the power circuit is further enhanced, the realization of extremely low stray inductance of the power circuit is facilitated, and the performance of the power module is improved.

When the external terminal is electrically connected with the power module through the bonding wire, bonding processes such as thick aluminum wire bonding, aluminum ribbon bonding, copper wire bonding and the like can be adopted, and when the external terminal is directly welded with the power module, welding processes such as solder paste welding, ultrasonic metal welding, laser welding and the like can be adopted. However, the present application is not limited thereto, and the present application is not limited thereto as the case may be.

Optionally, in an embodiment of the present application, the materials of the first conductive pad, the second conductive pad, the third conductive pad and the fourth conductive pad are conductive materials, preferably copper, and may also be molybdenum copper materials to achieve matching with the thermal expansion coefficient of the power chip. The material of the first conductive connecting piece and the second conductive connecting piece is conductive material, preferably copper. However, the materials of the first conductive pad, the second conductive pad, the third conductive pad, the fourth conductive pad, the first conductive connecting piece and the second conductive connecting piece are not limited, and may be other conductive materials, as appropriate.

From the above, the parts and the connection process between the parts in the power module provided by the application are all existing mature systems, and the existing materials and process flows can be reused, so that the power module provided by the application has strong practicability.

It is worth noting that the power module provided by the application is of a half-bridge structure, the DC+ terminals and the DC-terminals of the power module provided by the application can be further connected in parallel, the AC ends are respectively led out, the full-bridge or three-phase bridge topology is realized, and the system function requirement is met.

Correspondingly, the application further provides a packaging structure, which comprises the power module in any of the above embodiments, and the power module is described in detail in the foregoing embodiments, and is not described herein again.

In summary, the present application provides a power module, which includes: the power device comprises a substrate base plate, a first power chip positioned on the surface of a first metal layer in the substrate base plate, a second power chip positioned on the surface of a second metal layer, a second conductive base plate comprising a third metal layer, a second insulating layer and a fourth metal layer which are sequentially laminated, a first conductive cushion block positioned on the surface of the second metal layer and a second conductive cushion block positioned on the surface of the second power chip, wherein the first metal layer, the first power chip, the third metal layer, the first conductive cushion block, the second metal layer, the second power chip, the second conductive cushion block and the fourth metal layer are sequentially and electrically connected, the first metal layer is electrically connected with a DC+ terminal, the fourth metal layer is electrically connected with a DC-terminal, the DC+ terminal is a signal input port, and the DC-terminal is a signal output port. Therefore, in the power module, a current signal can be input through the first metal layer and sequentially flows through the first metal layer, the first power chip, the third metal layer, the first conductive cushion block, the second metal layer, the second power chip, the second conductive cushion block and the fourth metal layer, and finally, the power loop of the power module is output through the fourth metal layer, so that the power loop of the power module provided by the application has very high overlapping property, and the transmission directions of currents in the overlapping loops are opposite, therefore, the stray inductance of the power loop of the power module can be effectively reduced, the extremely low stray inductance of the power loop is realized, and the comprehensive performance of the power module can be improved.

In the present specification, each embodiment is described in a progressive manner, or a parallel manner, or a combination of progressive and parallel manners, and each embodiment is mainly described as different from other embodiments, and the same similar areas between the embodiments are referred to each other. For the device disclosed in the embodiment, since the device corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant points refer to the description of the method area.

It should be noted that, in the description of the present application, it should be understood that the directions or positional relationships indicated by the terms "upper", "lower", "top", "bottom", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present application and simplifying the description, and do not indicate or imply that the apparatus or element to be referred to must have a specific direction, be configured and operated in the specific direction, and thus should not be construed as limiting the present application. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present.

It is further noted that relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that an article or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such article or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in an article or apparatus that comprises such element.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (10)

1. A power module, comprising:

the substrate comprises a first insulating layer, a first metal layer and a second metal layer, wherein the first metal layer and the second metal layer are positioned on the surface of the first insulating layer;

at least one first power chip and at least one second power chip, the at least one first power chip being located on the surface of the first metal layer in electrical contact with the first metal layer, the at least one second power chip being located on the surface of the second metal layer in electrical contact with the second metal layer;

the first conductive substrate comprises a third metal layer, a second insulating layer and a fourth metal layer which are sequentially stacked along one side away from the surface of the first insulating layer, wherein the third metal layer is in electrical contact with the surface of the first power chip, the surface of the second metal layer is also provided with a first conductive cushion block, and the third metal layer is also in electrical contact with the surface of the first conductive cushion block;

The second conductive cushion blocks are in one-to-one correspondence with the second power chips, are positioned on the surfaces of the second power chips and are in electrical contact with the second power chips, and are also electrically connected with the fourth metal layer through the electrical connection structures;

the first metal layer is electrically connected with the DC+ terminal, the second metal layer is electrically connected with the AC terminal, the fourth metal layer is electrically connected with the DC-terminal, and current signals are input through the first metal layer and output through the fourth metal layer.

2. The power module of claim 1 wherein the electrical connection structure is a first conductive connection pad located on the at least one second conductive pad surface in electrical contact with the at least one second conductive pad and further located on the fourth metal layer surface in electrical contact with the fourth metal layer electrically connecting the second conductive pad and the fourth metal layer.

3. The power module of claim 1, wherein the electrical connection structure is at least one first bonding wire, the first bonding wire is in one-to-one correspondence with the second conductive pad, and one end of the first bonding wire is electrically connected with the second conductive pad, and the other end is electrically connected with the fourth metal layer.

4. The power module of claim 1, further comprising: the at least one third conductive cushion block is in one-to-one correspondence with the at least one first power chip, is positioned on the surface of the first power chip and is in electrical contact with the first power chip, is also in electrical contact with the third metal layer, and is electrically connected with the first power chip and the third metal layer.

5. The power module of claim 1, wherein the power module comprises a plurality of first power chips and a plurality of second power chips, wherein the plurality of first power chips are arranged in an array on the surface of the first metal layer, and the plurality of second power chips are arranged in an array on the surface of the second metal layer.

6. The power module of claim 1 wherein the substrate base further comprises a fifth metal layer on a back side of the first insulating layer, the fifth metal layer overlying the back side of the first insulating layer, the back side of the first insulating layer being opposite the surface of the first insulating layer.

7. The power module of claim 6, wherein the electrical connection structure is a second conductive substrate comprising a sixth metal layer, a third insulating layer, and a seventh metal layer sequentially stacked along a side facing away from the first insulating layer surface, the sixth metal layer covering the second conductive pad surface and the fourth metal layer surface and extending in a first direction at least to an edge of the fourth metal layer;

The first direction is parallel to the arrangement direction of the second power chip and the first power chip.

8. The power module of claim 7, further comprising: the second conductive connecting sheet, the fourth conductive cushion block and the eighth metal layer are positioned on the surface of the first insulating layer;

the fourth conductive cushion block is located on the surface of the eighth metal layer and is in electrical contact with the eighth metal layer, the second conductive connecting sheet is located on the surface of the fourth metal layer and the surface of the fourth conductive cushion block, the fourth metal layer is electrically connected with the eighth metal layer, and the eighth metal layer is electrically connected with the DC-terminal.

9. The power module of claim 1, wherein the dc+ terminals, the DC-terminals, and the AC terminals are copper bar terminals, wherein the DC-terminals and the dc+ terminals are arranged in sequence along a second direction and at least partially overlap in a first direction, the first direction being parallel to an arrangement direction of the second power chip and the first power chip, the second direction being perpendicular to the first insulating layer surface;

the power chip further includes: the second bonding wire is electrically connected with the DC+ terminal and the first metal layer, the third bonding wire is electrically connected with the DC-terminal and the fourth metal layer, and the fourth bonding wire is electrically connected with the second metal layer and the AC terminal.

10. The power module of claim 1, wherein the dc+ terminals, the DC-terminals, and the AC terminals are copper bar terminals, the dc+ terminals are in electrical contact with the first metal layer, the DC-terminals are in electrical contact with the fourth metal layer, and the AC terminals are in electrical contact with the second metal layer;

the DC-terminals and the DC+ terminals are sequentially arranged along a second direction and at least partially overlap in a first direction, the first direction is parallel to the arrangement direction of the second power chip and the first power chip, and the second direction is perpendicular to the surface of the first insulating layer.