Bidirectional power module packaging structure and packaging method

Abstract

According to the bidirectional power module packaging structure and method, in the structure, a first access end is configured to be an inlet wire terminal of an IGBT power module, a second access end is configured to be an outlet wire terminal of the IGBT power module, a forward power module is arranged between the first access end and the second access end and comprises three positive sub-modules which are arranged in a laminated mode, and a reverse power module is arranged between the three positive sub-modules. The three positive sub-modules are connected with the first access end and the second access end, the DBC substrate is arranged between the first access end and the second access end, one end of the first connecting end is connected with the first access end, the other end of the first connecting end is connected with the DBC substrate, one end of the second connecting end is connected with the second access end, the other end of the second connecting end is connected with the DBC substrate, and the IGBT chip is arranged on the upper surface of the DBC substrate. The FRD chips are arranged on the upper surface of the DBC substrate and are arranged at intervals with the IGBT chips, and the bonding wires are connected with the FRD chips and the IGBT chips; the reverse power module is arranged between the first access end and the second access end.

Description

Technical Field

[0001] The invention relates to the technical field of power electronics, and in particular to a bidirectional power module packaging structure and a packaging method. Background Art

[0002] With the rapid development of urban rail transit DC systems, DC microgrids, ship DC systems, etc. and the continuous increase in power system capacity, the stable and safe operation of DC systems is of vital importance. Short-circuit faults are the most likely and most harmful faults in DC transmission systems. When a short-circuit fault occurs in a low-voltage DC system, the rapidly rising short-circuit current will cause very serious consequences if it is not removed. Therefore, low-voltage DC circuit breakers with fault isolation and removal functions are indispensable for achieving safe and reliable operation of DC systems.

[0003] Hybrid DC circuit breakers use mechanical switches and solid-state switch branches in parallel. Mechanical switches carry the load current under normal conditions and have low conduction losses. Solid-state switches cut off fault currents and break current quickly. Hybrid DC circuit breakers overcome the shortcomings of long mechanical breaking time and high solid-state conduction losses, and have become one of the main research directions of DC circuit breakers. The current carrying capacity and commutation performance of the solid-state switch branch are key factors in determining the performance of hybrid solid-state circuit breakers.

[0004] However, due to the limitations of semiconductor materials and manufacturing process technology, the capacity of a single power semiconductor device is limited, and when used with solid-state switches, it is often necessary to use it in parallel to improve the shutdown capability. Using separate devices directly in parallel has the problems of large stray inductance, large volume, and poor balance of each parallel branch.

[0005] Therefore, it is necessary to provide a bidirectional IGBT module packaging structure for improving the dynamic current sharing characteristics of parallel IGBT devices, thereby improving the shutdown capability of the DC circuit breaker.

[0006] The information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Summary of the invention

[0007] In view of the shortcomings or defects of the existing technology, a bidirectional power module packaging structure and packaging method are provided. Compared with the traditional single-layer IGBT module structure, the stacked structure realizes the spatial symmetry of multiple parallel IGBT chips, which is beneficial to improving the dynamic current sharing characteristics of the IGBT.

[0008] The purpose of the present invention is achieved through the following technical solutions.

[0009] A bidirectional power module packaging structure includes: The first access terminal is configured as an input terminal of the IGBT power module. The second access terminal is configured as an output terminal of the IGBT power module. A forward power module is provided between a first access terminal and a second access terminal, and comprises three stacked positive submodules, wherein the three positive submodules are connected to the first access terminal and the second access terminal, and the positive submodule comprises: A DBC substrate is provided between the first access end and the second access end, A first connection end, one end of which is connected to the first access end, and the other end of which is connected to the DBC substrate, A second connection end, one end of which is connected to the second access end, and the other end is connected to the DBC substrate, An IGBT chip is arranged on the upper surface of the DBC substrate. The FRD chip is arranged on the upper surface of the DBC substrate and is separated from the IGBT chip. A bonding wire connecting the FRD chip and the IGBT chip; The reverse power module is arranged between the first access terminal and the second access terminal, and includes three stacked reverse submodules, the three reverse submodules are connected to the first access terminal and the second access terminal, and the reverse submodule includes: A first connection end, one end of which is connected to the first access end, and the other end of which is connected to the DBC substrate, A second connection end, one end of which is connected to the second access end, and the other end is connected to the DBC substrate, An IGBT chip is arranged on the lower surface of the DBC substrate. The FRD chip is arranged on the lower surface of the DBC substrate and is spaced apart from the IGBT chip. A bonding wire connects the FRD chip and the IGBT chip.

[0010] In the bidirectional power module packaging structure, the forward power module and the reverse power module are connected in reverse parallel via the first access terminal and the second access terminal.

[0011] In the bidirectional power module packaging structure, the first terminal is connected to the positive electrode of the IGBT chip, and the second terminal is connected to the negative electrode of the FRD chip.

[0012] In the bidirectional power module packaging structure, the bonding wire connects the negative electrode of the IGBT chip with the positive electrode of the FRD chip.

[0013] In the bidirectional power module packaging structure, two or more parallel-connected IGBT chips are integrated inside the positive submodule or the negative submodule.

[0014] In the bidirectional power module packaging structure, two or more parallel-connected FRD chips are integrated inside the positive submodule or the negative submodule.

[0015] In the bidirectional power module packaging structure, the DBC substrate is a horizontal plate that remains horizontal.

[0016] In the bidirectional power module packaging structure, the IGBT chip and the FRD chip are welded to the copper layer of the DBC substrate by low-temperature silver sintering or high-temperature welding process.

[0017] In the bidirectional power module packaging structure, the bidirectional power module packaging structure is a symmetrical structure.

[0018] The method for using the bidirectional power module packaging structure includes the following steps: Processing the DBC substrate so that the copper layer of the DBC substrate is divided into multiple conductive areas according to the set gaps; Arrange IGBT and FRD power chips, and multiple IGBT chips or FRD chips are connected in parallel; Welding chips, using processes such as silver sintering or welding to electrically connect multiple IGBT chips and FRD chips to the DBC substrate; Welding the first connection end and the second connection end to the DBC substrate; Bonding: connecting the first terminal to the positive electrode of the IGBT chip and the second terminal to the negative electrode of the FRD chip through a bonding wire, and connecting the negative electrode of the IGBT chip to the positive electrode of the FRD chip.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The stacked submodules of the present invention enable the IGBT chips to be symmetrically arranged in three-dimensional space, and the balance of the stray inductance of each branch IGBT is increased, which is beneficial to improving the dynamic current sharing characteristics of the IGBT module. The present invention is beneficial to improving the power density of the IGBT module used in the DC circuit breaker and improving its breaking performance.

[0020] The above description is only an overview of the technical solution of the present invention. In order to make the technical means of the present invention clearer and to achieve the extent that those skilled in the art can implement it according to the contents of the specification, and in order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are exemplified below. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] By reading the detailed description of the preferred specific embodiments below, various other advantages and benefits of the present invention will become clear to those of ordinary skill in the art. The drawings in the specification are only for the purpose of illustrating the preferred embodiments and are not considered to be limitations of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative work. Moreover, the same reference numerals are used to represent the same components throughout the drawings.

[0022] In the attached picture: Figure 1 It is a schematic diagram of the packaging structure of a bidirectional IGBT power module according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the topology of a bidirectional IGBT circuit according to an embodiment of the present invention; Figure 3 It is a schematic diagram of the arrangement of submodules in one embodiment of the present invention; Figure 4 It is a schematic structural diagram of a forward power module according to an embodiment of the present invention.

[0023] The present invention is further explained below in conjunction with the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0024] The specific embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the specific embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0025] It should be noted that certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different nouns to refer to the same component. This specification and claims do not use the difference in nouns as a way to distinguish components, but use the difference in the functions of the components as the criterion for distinction. As mentioned throughout the specification and claims, "including" or "comprising" is an open term, so it should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the present invention, but the description is based on the general principles of the specification and is not intended to limit the scope of the present invention. The scope of protection of the present invention shall be determined by the attached claims.

[0026] To facilitate understanding of the embodiments of the present invention, several specific embodiments will be further explained below with reference to the accompanying drawings, and each of the accompanying drawings does not constitute a limitation on the embodiments of the present invention.

[0027] For a better understanding, Figures 1 to 4 As shown, a bidirectional power module packaging structure includes: The first access terminal 113 is configured as an input terminal of the IGBT power module. The second access terminal 114 is configured as an output terminal of the IGBT power module. The forward power module 111 is arranged between the first access terminal 113 and the second access terminal 114, and includes three stacked positive submodules, which are connected to the first access terminal 113 and the second access terminal 114. The positive submodule includes: The DBC substrate 104 is disposed between the first access end 113 and the second access end 114. The first connection end 105 has one end connected to the first access end 113 and the other end connected to the DBC substrate 104. The second connection end 106 has one end connected to the second access end 114 and the other end connected to the DBC substrate 104. The IGBT chip 101 is disposed on the upper surface of the DBC substrate 104. The FRD chip 102 is disposed on the upper surface of the DBC substrate 104 and is arranged between the IGBT chip 101. A bonding wire 103 connecting the FRD chip 102 and the IGBT chip 101; The reverse power module 112 is arranged between the first access terminal 113 and the second access terminal 114, and includes three stacked reverse submodules, which are connected to the first access terminal 113 and the second access terminal 114. The reverse submodule includes: The first connection end 105 has one end connected to the first access end 113 and the other end connected to the DBC substrate 104. The second connection end 106 has one end connected to the second access end 114 and the other end connected to the DBC substrate 104. The IGBT chip 101 is disposed on the lower surface of the DBC substrate 104. The FRD chip 102 is disposed on the lower surface of the DBC substrate 104 and is spaced apart from the IGBT chip 101. The bonding wire 103 connects the FRD chip 102 and the IGBT chip 101 .

[0028] In a preferred embodiment of the bidirectional power module packaging structure, the forward power module 111 and the reverse power module 112 are connected in reverse parallel via a first access terminal 113 and a second access terminal 114 .

[0029] In a preferred embodiment of the bidirectional power module packaging structure, the first terminal is connected to the positive electrode of the IGBT chip 101 , and the second terminal is connected to the negative electrode of the FRD chip 102 .

[0030] In a preferred embodiment of the bidirectional power module packaging structure, the bonding wire 103 connects the negative electrode of the IGBT chip 101 with the positive electrode of the FRD chip 102 .

[0031] In a preferred embodiment of the bidirectional power module packaging structure, two or more parallel-connected IGBT chips 101 are integrated inside the positive submodule or the negative submodule.

[0032] In a preferred embodiment of the bidirectional power module packaging structure, two or more parallel-connected FRD chips 102 are integrated inside the positive submodule or the negative submodule.

[0033] In a preferred embodiment of the bidirectional power module packaging structure, the DBC substrate 104 is a horizontal plate that is kept horizontal.

[0034] In the preferred embodiment of the bidirectional power module packaging structure, the IGBT chip 101 and the FRD chip 102 are welded to the copper layer of the DBC substrate 104 by low-temperature silver sintering or high-temperature welding process.

[0035] In a preferred embodiment of the bidirectional power module packaging structure, the bidirectional power module packaging structure is a symmetrical structure.

[0036] The method for using the bidirectional power module packaging structure includes the following steps: Processing the DBC substrate 104 so that the copper layer of the DBC substrate 104 is divided into a plurality of conductive areas according to a set gap; Arrange IGBT and FRD power chips, and multiple IGBT chips 101 or FRD chips 102 are connected in parallel; Welding chips, electrically connecting multiple IGBT chips 101 and FRD chips 102 to the DBC substrate 104 through processes such as silver sintering or welding; Welding the first connection end 105 and the second connection end 106 to the DBC substrate 104; Bonding: connecting the first terminal to the positive electrode of the IGBT chip 101 and the second terminal to the negative electrode of the FRD chip 102 through the bonding wire 103, thereby connecting the negative electrode of the IGBT chip 101 to the positive electrode of the FRD chip 102.

[0037] In one embodiment, the first access terminal 113 and the second access terminal 114 both include an E-type structure for connecting the positive power module 111 or the negative power module and an access board for connecting the E-type structure, wherein the access board is provided with a through hole.

[0038] In one embodiment, the bidirectional IGBT power module can adjust the number of sub-modules according to the number of IGBTs and FRD chips 102 connected in parallel to achieve a better symmetry effect.

[0039] In one embodiment, when the bidirectional IGBT power module is turned on, a bidirectional current can flow through the power module; when the IGBT is turned off, a bidirectional current cannot flow through the module.

[0040] Figure 1 Schematic diagram of the packaging structure of a bidirectional IGBT power module according to an embodiment of the present invention. The packaging structure of the bidirectional power module includes: The first access terminal 113 is configured as an incoming line terminal of the IGBT power module.

[0041] The second access terminal 114 is configured as an output terminal of the IGBT power module.

[0042] In some embodiments of the present application, the forward power module 111 includes three stacked submodules therein, and the three submodules are connected via a first access terminal 113 and a second access terminal 114 .

[0043] The composition and structure of the reverse power module 112 are the same as those of the forward power module 111 .

[0044] In some embodiments of the present application, the forward power module and the reverse power module are connected in reverse parallel via the first access terminal and the second access terminal.

[0045] In some embodiments of the present application, the submodule includes a first connection terminal 105 , a second connection terminal 106 , a DBC substrate 104 , an IGBT chip 101 , an FRD chip 102 , and a bonding wire 103 .

[0046] In some embodiments of the present application, the IGBT chip and the FRD chip are welded to the copper layer of the DBC substrate by low-temperature silver sintering or high-temperature welding process.

[0047] In some embodiments of the present application, the first terminal is connected to the positive electrode of the IGBT chip, and the second terminal is connected to the negative electrode of the FRD chip.

[0048] In some embodiments of the present application, the bonding wire connects the negative electrode of the IGBT chip with the positive electrode of the FRD chip.

[0049] Figure 2The diagram is a schematic diagram of a submodule circuit topology structure in a bidirectional IGBT power module according to an embodiment of the present invention.

[0050] Figure 3 It is a schematic diagram of the arrangement of submodules in one embodiment of the present invention.

[0051] In one embodiment, two IGBT chips 101 and two FRD chips 102 are symmetrically arranged on a DBC substrate 104. The first connection end 105 is configured as a positive terminal welded on the DBC substrate, and the second connection end 106 is configured as a negative terminal welded on the DBC substrate. The negative electrode of the IGBT chip is electrically connected to the positive electrode of the FRD chip through a bonding wire 103.

[0052] Figure 4 It is a schematic structural diagram of a forward power module according to an embodiment of the present invention, comprising three stacked submodules.

[0053] In the present invention, the packaging method of the submodule in an embodiment includes the following steps: The DBC substrate is processed so that the copper layer of the DBC substrate is divided into multiple conductive areas according to set gaps.

[0054] Arrange IGBT and FRD power chips. Multiple IGBTs or FRDs are connected in parallel.

[0055] Welding the chip: The multi-power chip in the layout of an embodiment is reliably electrically connected to the DBC substrate through processes such as silver sintering or welding.

[0056] Welding the power terminal and the driving terminal. In one embodiment, the first connection terminal 105 and the second connection terminal 106 are welded to a specific area on the DBC substrate, and the driving terminal 107 is welded in the same manner.

[0057] Bonding: Use bonding wires to connect the drive terminal to the power chip electrode, and connect the negative electrode of the IGBT chip to the positive electrode of the FRD chip.

[0058] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.

[0059] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A bidirectional power module packaging structure, It is characterized in that These include, The first access terminal is configured as an input terminal of the IGBT power module. The second access terminal is configured as an output terminal of the IGBT power module. A forward power module is provided between a first access terminal and a second access terminal, and comprises three stacked positive submodules, wherein the three positive submodules are connected to the first access terminal and the second access terminal, and the positive submodule comprises: A DBC substrate is provided between the first access end and the second access end, A first connection end, one end of which is connected to the first access end, and the other end of which is connected to the DBC substrate, A second connection end, one end of which is connected to the second access end, and the other end is connected to the DBC substrate, An IGBT chip is arranged on the upper surface of the DBC substrate. The FRD chip is arranged on the upper surface of the DBC substrate and is separated from the IGBT chip. A bonding wire connecting the FRD chip and the IGBT chip; The reverse power module is arranged between the first access terminal and the second access terminal, and includes three stacked reverse submodules, the three reverse submodules are connected to the first access terminal and the second access terminal, and the reverse submodule includes: A first connection end, one end of which is connected to the first access end, and the other end of which is connected to the DBC substrate, A second connection end, one end of which is connected to the second access end, and the other end is connected to the DBC substrate, An IGBT chip is arranged on the lower surface of the DBC substrate. The FRD chip is arranged on the lower surface of the DBC substrate and is spaced apart from the IGBT chip. A bonding wire connects the FRD chip and the IGBT chip.

2. The bidirectional power module packaging structure according to claim 1, It is characterized in that Preferably, the forward power module and the reverse power module are connected in reverse parallel via a first access terminal and a second access terminal.

3. The bidirectional power module packaging structure according to claim 1, It is characterized in that The first terminal is connected to the positive electrode of the IGBT chip, and the second terminal is connected to the negative electrode of the FRD chip.

4. The bidirectional power module packaging structure according to claim 1, It is characterized in that The bonding wire connects the negative electrode of the IGBT chip with the positive electrode of the FRD chip.

5. The bidirectional power module packaging structure according to claim 1, It is characterized in that The positive submodule or the negative submodule internally integrates two or more parallel-connected IGBT chips.

6. The bidirectional power module packaging structure according to claim 1, It is characterized in that The positron module or the inverse module internally integrates two or more parallel-connected FRD chips.

7. The bidirectional power module packaging structure according to claim 1, It is characterized in that The DBC substrate is a horizontal plate that maintains horizontality.

8. The bidirectional power module packaging structure according to claim 1, It is characterized in that The IGBT chip and the FRD chip are welded to the copper layer of the DBC substrate through low-temperature silver sintering or high-temperature welding process.

9. The bidirectional power module packaging structure according to claim 1, It is characterized in that The packaging structure of the bidirectional power module is a symmetrical structure.

10. A method for using the bidirectional power module packaging structure according to any one of claims 1 to 9, It is characterized in that It includes the following steps, Processing the DBC substrate so that the copper layer of the DBC substrate is divided into multiple conductive areas according to the set gaps; Arrange IGBT and FRD power chips, and multiple IGBT chips or FRD chips are connected in parallel; Welding chips, using processes such as silver sintering or welding to electrically connect multiple IGBT chips and FRD chips to the DBC substrate; Welding the first connection end and the second connection end to the DBC substrate; Bonding: connecting the first terminal to the positive electrode of the IGBT chip and the second terminal to the negative electrode of the FRD chip through a bonding wire, and connecting the negative electrode of the IGBT chip to the positive electrode of the FRD chip.

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