Packaging structure and power conversion device

Abstract

The invention provides a packaging structure and a power conversion device, the packaging structure comprises a lead frame, a first diode chip, a second diode chip, a first bonding piece and a plastic package body, the first diode chip and the second diode chip are both provided with a first electrode and a second electrode, the first electrode of the first diode chip and the first electrode of the second diode chip are welded on the surface of the lead frame, and the first electrode of the first diode chip and the first electrode of the second diode chip are electrically connected through the lead frame. The second electrode of the first diode chip and the second electrode of the second diode chip are in bonding connection through a first bonding piece, and the plastic package body wraps the first diode chip, the second diode chip and the first bonding piece. According to the invention, the parasitic inductance between the second electrode of the first diode chip and the second electrode of the second diode chip is reduced, so that the amplitude of voltage oscillation between the second electrode of the first diode chip and the second electrode of the second diode chip is suppressed, and the problem of electromagnetic compatibility oscillation is eliminated.

Description

Technical Field

[0001] This application relates to the technical field of power conversion, and particularly to a packaging structure and a power conversion device. Background Art

[0002] The common cathode diode is a commonly used device in a power conversion device. The common cathode diode is generally electrically connected to a switching device. During the operation of the power conversion device, the frequent conduction and turn-off of the switching device will cause the potential at both ends of the common cathode diode to jump, resulting in electromagnetic compatibility (EMC) oscillation problems. Summary of the Invention

[0003] Embodiments of this application provide a packaging structure and a power conversion device to eliminate the electromagnetic compatibility oscillation problem of the packaging structure.

[0004] In a first aspect, embodiments of this application provide a packaging structure. The packaging structure provided by the embodiments of this application may include: a lead frame, a first diode chip, a second diode chip, a first bonding member, and a plastic package. Both the first diode chip and the second diode chip are located on the lead frame. Both the first diode chip and the second diode chip have a first electrode and a second electrode. In the embodiments of this application, the first electrode is the anode of the diode chip, and the second electrode is the cathode of the diode chip; alternatively, the first electrode is the cathode of the diode chip, and the second electrode is the anode of the diode chip. The first electrodes of the first diode chip and the second diode chip are both welded to the surface of the lead frame. The lead frame includes a conductive material. For example, the lead frame may include metal materials such as copper, iron, and aluminum. The first electrodes of the first diode chip and the second diode chip are electrically connected through the lead frame. The second electrodes of the first diode chip and the second diode chip are bonded and connected through the first bonding member. The plastic package wraps the first diode chip, the second diode chip, and the first bonding member.

[0005] In the encapsulation structure provided by the embodiments of the present application, the first electrodes of the first diode chip and the second diode chip are electrically connected through a lead frame. The first electrode can be the cathode or anode of the diode. Therefore, the encapsulation structure provided by the embodiments of the present application can be a common-cathode diode encapsulation structure, or it can also be a common-anode diode encapsulation structure. In the embodiments of the present application, by providing a first bonding member in the encapsulation structure, the second electrodes of the first diode chip and the second diode chip can be bonded and connected through the first bonding member. In this way, the parasitic inductance between the second electrodes of the first diode chip and the second diode chip can be reduced, thereby suppressing the amplitude of the voltage oscillation between the second electrodes of the first diode chip and the second diode chip and eliminating the electromagnetic compatibility oscillation problem. Moreover, the second electrodes of the first diode chip and the second diode chip are bonded and connected through the first bonding member, which will not affect the connection relationship between the first diode chip and the second diode chip and other components, nor will it affect the overall performance of the encapsulation structure.

[0006] In addition, the plastic encapsulant wraps the first diode chip, the second diode chip, and the first bonding member. The encapsulation body can play a role in protecting and fixing each component. Encapsulating the first bonding member inside the plastic encapsulant can prevent the first bonding member from being exposed outside the encapsulation structure, which will not cause electrical safety and reliability problems and ensure that the encapsulation structure has high safety and reliability. The first bonding member in the embodiments of the present application can be a bonding wire, a strip structure, a sheet structure, etc. Exemplarily, the strip structure can be an aluminum ribbon, and the sheet structure can be a copper clip. Exemplarily, the first bonding member can include metal materials such as copper, aluminum, gold, silver, etc., or the first bonding member can also include other conductive materials. During the manufacturing process, the first bonding member can be manufactured by a bonding process or other processes, which is easily compatible with the manufacturing processes of other components in the encapsulation structure. For example, the first bonding wire can be manufactured during the wire bond process in the front of line (FOL) of the encapsulation process. The manufacturing process has high feasibility and stability, and the manufacturing cost is low, having high manufacturability and supplyability.

[0007] In the embodiments of the present application, the encapsulation structure is provided with a first diode chip and a second diode chip, and the first diode chip and the second diode chip are arranged in parallel. That is to say, there are two diode chips arranged in parallel in the encapsulation structure. In specific implementation, more diode chips arranged in parallel can be provided in the encapsulation structure. Or, other electronic components can also be provided in the encapsulation structure, which can be set according to actual needs. The encapsulation structure in the embodiments of the present application can adopt a transistor outline (TO), or the encapsulation structure can also adopt other encapsulation forms.

[0008] In the embodiment of the present application, the first electrode of the first diode chip may be located on the lower surface of the first diode chip, and the second electrode of the first diode chip may be located on the upper surface of the first diode chip. The first electrode of the second diode chip may be located on the lower surface of the second diode chip, and the second electrode of the second diode chip may be located on the upper surface of the second diode chip. Among them, the upper surface of the first diode chip (or the second diode chip) is the surface of the first diode chip (or the second diode chip) facing away from the lead frame, and the lower surface is the surface of the first diode chip (or the second diode chip) close to the lead frame. In the embodiment of the present application, setting the first electrode and the second electrode of the first diode chip (or the second diode chip) on the lower surface and the upper surface respectively facilitates electrical connection with other components. Moreover, the first electrodes of the first diode chip and the second diode chip are located on the surfaces of the same side, and the second electrodes are located on the surfaces of the same side, which facilitates electrical connection of the first electrodes of the first diode chip and the second diode chip and electrical connection of the second electrodes of the first diode chip and the second diode chip. Since the lead frame in the embodiment of the present application includes a conductive material, when the first diode chip and the second diode chip are mounted at corresponding positions on the surface of the lead frame, electrical connection of the first electrodes of the first diode chip and the second diode chip can be achieved. By overlapping the first bonding member on the upper surfaces of the first diode chip and the second diode chip, electrical connection between the second electrodes of the first diode chip and the second diode chip can be achieved through the first bonding member.

[0009] Of course, in some cases, the first electrode and the second electrode of the first diode chip (or the second diode chip) may also be set on the surfaces of the same side. For example, the first electrode and the second electrode of the first diode chip (or the second diode chip) may be set at different positions on the upper surface, and electrical connection with other components can also be achieved, which can be set according to the spatial layout of the package structure.

[0010] In some embodiments of the present application, the second electrodes of the first diode chip and the second diode chip can be electrically connected to different pins respectively. The lead frame can include: a separately provided carrier plate, a first pin, and a second pin. The first diode chip and the second diode chip are located above the carrier plate, and the carrier plate can play roles such as support and heat dissipation. The first electrodes of the first diode chip and the second diode chip are both welded to the surface of the carrier plate. The second electrode of the first diode chip is electrically connected to the first pin, and the second electrode of the second diode chip is electrically connected to the second pin. The first pin and the second pin can play the role of signal connection, and the packaging structure can be electrically connected to other components through the first pin and the second pin. In specific implementation, a part of the first pin is wrapped by the encapsulant, and the other part is exposed outside the encapsulant. A part of the second pin is wrapped by the encapsulant, and the other part is exposed outside the encapsulant. For example, when the first pin and the second pin are strip-shaped, the encapsulant can wrap most of the first pin and the second pin, leaving the ends of the first pin and the second pin exposed, facilitating the electrical connection of the packaging structure to other components through the first pin and the second pin. Of course, in some cases, the encapsulant can also completely wrap the first pin and the second pin, and other connecting components can be used to lead out the first pin and the second pin.

[0011] In a possible implementation manner, the packaging structure in the embodiments of the present application can further include: a second bonding member and a third bonding member, and the encapsulant wraps the second bonding member and the third bonding member. The second electrode of the first diode chip and the first pin are bonded and connected through the second bonding member, and the second electrode of the second diode chip and the second pin are bonded and connected through the third bonding member. In specific implementation, the widths of the first bonding member, the second bonding member, and the third bonding member can be substantially the same. Exemplarily, the first bonding member, the second bonding member, and the third bonding member can all be bonding wires. In the manufacturing process, bonding wires made of metals with relatively high purity can be used to make the first bonding wire, the second bonding wire, and the third bonding wire. For example, bonding wires made of metal materials such as copper, aluminum, gold, and silver can be used. Of course, in some cases, other conductive materials can also be used to make the first bonding wire, the second bonding wire, and the third bonding wire. In the manufacturing process, the first bonding wire can be made by using the wire bonding process. In order to improve the manufacturing efficiency, the first bonding wire, the second bonding wire, and the third bonding wire can be made by using the same bonding process at one time.

[0012] In another possible implementation manner, the width of the first bonding member can be greater than the widths of the second bonding member and the third bonding member. Exemplarily, the first bonding member can be a strip structure. For example, it can be an aluminum ribbon, and the second bonding member and the third bonding member can be bonding wires.

[0013] Of course, in some cases, other bonding methods can also be used to make the first bonding member, which is not limited herein.

[0014] In another possible implementation, the encapsulation structure in the embodiments of the present application may further include: a second bonding member, and the plastic package body wraps the second bonding member. The first bonding member is bonded to the second electrode of the first diode chip, the second electrode of the second diode chip, and the first pin. The second bonding member is bonded to the second electrode of the first diode chip, the second electrode of the second diode chip, and the second pin. In specific implementation, when the second electrodes of the first diode chip and the second diode chip are both located on the upper surface, the first bonding member can be lapped on the upper surfaces of the first diode chip, the second diode chip, and the first pin, and the second bonding member can be lapped on the upper surfaces of the first diode chip, the second diode chip, and the second pin.

[0015] The first bonding member can be a folded linear integral structure, and the first bonding member can be bent on the upper surface of the first diode chip. The second bonding member can be a folded linear integral structure, and the second bonding member can be bent on the upper surface of the second diode chip. In the manufacturing process, the first bonding member can be fabricated by a bonding process. During the bonding process, three solder joints (the first solder joint, the second solder joint, and the third solder joint) can be set. The first solder joint can be located on the upper surface of the second diode chip, the second solder joint can be located on the upper surface of the first diode chip, and the third solder joint can be located on the upper surface of the first pin. The first bonding member can be bent at the second solder joint without breaking the first bonding member, so as to achieve that the same first bonding member is lapped on the upper surfaces of the first diode chip, the second diode chip, and the first pin, thereby obtaining the folded linear integral first bonding member. Similarly, the second bonding member can be fabricated in a similar manner, which will not be elaborated here.

[0016] In another possible implementation, the first bonding member can be bonded to the second electrode of the first diode chip, the second electrode of the second diode chip, the first lead and the second lead. The first bonding member can be a one-piece structure in a zigzag shape, and the first bonding member can be bent on the upper surfaces of the first diode chip and the second diode chip. In specific implementation, when the second electrodes of the first diode chip and the second diode chip are both located on the upper surface, the first bonding member can be lapped on the upper surfaces of the first diode chip, the second diode chip, the first lead and the second lead. Exemplarily, the first bonding member can be a sheet structure, and the fabricated first bonding member in a zigzag shape can be bonded to the upper surfaces of the first diode chip, the second diode chip, the first lead and the second lead. Alternatively, the first bonding member can also be a bonding wire. During the bonding process, four solder joints can be provided on the surfaces of the first diode chip, the second diode chip, the first lead and the second lead respectively, and the bonding wire can be bent at the second solder joint and the third solder joint without breaking the bonding wire, so as to lap the same bonding wire on the upper surfaces of the first diode chip, the second diode chip, the first lead and the second lead, thereby obtaining the first bonding member which is integrally in a zigzag shape.

[0017] In some other embodiments of the present application, the second electrodes of the first diode chip and the second diode chip can be electrically connected to the same lead. The lead frame can include: a separately provided carrier plate and a first lead. The first electrodes of the first diode chip and the second diode chip are both welded to the surface of the carrier plate, and the carrier plate can play roles such as support and heat dissipation. The second electrodes of the first diode chip and the second diode chip are both electrically connected to the first lead. The first lead can play a role in signal connection, and the package structure can be electrically connected to other components through the first lead. In specific implementation, a part of the first lead is wrapped by the encapsulant, and the other part is exposed outside the encapsulant. For example, when the first lead is in a long strip shape, the encapsulant can wrap most of the first lead, leaving the end of the first lead exposed, which is convenient for the package structure to be electrically connected to other components through the first lead. Of course, in some cases, the encapsulant can also completely wrap the first lead, and other connecting components can be used to lead out the first lead.

[0018] In a possible implementation, the encapsulation structure in the embodiments of the present application may further include: a second bonding member and a third bonding member, and the plastic package body wraps the second bonding member and the third bonding member. The second electrode of the first diode chip is bonded to the first pin through the second bonding member, and the second electrode of the second diode chip is bonded to the first pin through the third bonding member. In specific implementation, the widths of the first bonding member, the second bonding member, and the third bonding member may be substantially the same. Exemplarily, the first bonding member, the second bonding member, and the third bonding member may all be bonding wires. In the manufacturing process, bonding wires made of metals with relatively high purity may be used to make the first bonding wire, the second bonding wire, and the third bonding wire. For example, bonding wires made of metal materials such as copper, aluminum, gold, and silver may be used. Of course, in some cases, other conductive materials may also be used to make the first bonding wire, the second bonding wire, and the third bonding wire. In the manufacturing process, the wire bonding process may be used to make the first bonding wire. In order to improve the manufacturing efficiency, the same bonding process may be used to make the first bonding wire, the second bonding wire, and the third bonding wire. Of course, in some cases, other bonding methods may also be used to make the first bonding member, and the width of the first bonding member may be greater than or less than the width of the second bonding member (or the third bonding member), which may be set according to actual needs and is not limited herein.

[0019] In another possible implementation, the first bonding member is bonded to the second electrode of the first diode chip, the second electrode of the second diode chip, and the first pin. The first bonding member is a folded one-piece structure, and the first bonding member can be bent on the upper surfaces of the first diode chip and the second diode chip. In specific implementation, when the second electrodes of the first diode chip and the second diode chip are both located on the upper surface, the first bonding member can be lapped on the upper surfaces of the first diode chip, the second diode chip, and the first pin. Exemplarily, the first bonding member may be a sheet-like structure, and the made folded first bonding member can be bonded to the upper surfaces of the first diode chip, the second diode chip, and the first pin. Or, the first bonding member may also be a bonding wire. In the bonding process, a solder joint may be respectively arranged on the surfaces of the first diode chip and the second diode chip, two solder joints may be arranged on the surface of the first pin, and the bonding wire is bent at the second and third solder joints but not broken, so as to realize that the same bonding wire is lapped on the upper surfaces of the first diode chip, the second diode chip, and the first pin, thereby obtaining the folded one-piece first bonding member.

[0020] The above introduces several ways for the second electrodes of the first diode chip and the second diode chip to achieve electrical connection through the first bonding member. In specific implementation, each connecting member in the encapsulation structure may also have other implementation manners, which will not be exemplified one by one here.

[0021] Second aspect, the embodiments of the present application further provide a power conversion device. The power conversion device in the embodiments of the present application can be devices such as charging piles, household photovoltaic devices, power stations, energy storage devices, inverters, etc. The power conversion device in the embodiments of the present application may include: any of the packaging structures and switching devices in the first aspect above. Since the first bonding member is provided in the above packaging structure in the embodiments of the present application, the second electrodes of the first diode chip and the second diode chip can be bonded and connected through the first bonding member, reducing the parasitic inductance between the second electrodes of the first diode chip and the second diode chip, thereby suppressing the amplitude of the voltage oscillation between the second electrodes of the first diode chip and the second diode chip, and eliminating the electromagnetic compatibility oscillation problem. Therefore, the power conversion device including the above packaging structure will not be interfered by electromagnetic compatibility oscillation, and the performance of the power conversion device is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the equivalent circuit of the common cathode diode;

[0023] Figure 2 Top view structural schematic diagram of the packaging structure provided by the embodiment of the present application;

[0024] Figure 3 is Figure 2 Cross-sectional schematic diagram at the dashed line AA' in

[0025] Figure 4 is Figure 2 Equivalent circuit schematic diagram of the packaging structure shown;

[0026] Figure 5 Another top view structural schematic diagram of the packaging structure provided by the embodiment of the present application;

[0027] Figure 6 Another top view structural schematic diagram of the packaging structure provided by the embodiment of the present application;

[0028] Figure 7 Another top view structural schematic diagram of the packaging structure provided by the embodiment of the present application;

[0029] Figure 8 Another top view structural schematic diagram of the packaging structure provided by the embodiment of the present application;

[0030] Figure 9 Another top view structural schematic diagram of the packaging structure provided by the embodiment of the present application.

[0031] Reference numerals:

[0032] 11 - Lead frame; 111 - Carrier plate; 112 - First pin; 113 - Second pin; 121 - First diode chip; 122 - Second diode chip; 131 - First bonding member; 132 - Second bonding member; 133 - Third bonding member; 14 - Plastic package; Q1 - Cathode pin; Q2, Q3 - Anode pins; L1, L2, L3 - Parasitic inductances; C1, C2 - Parasitic capacitances; P1 - First electrode; P2 - Second electrode. Detailed implementation manners

[0033] In related technologies, a common - cathode diode is a commonly - used device in a power conversion device. Figure 1 For the equivalent circuit schematic diagram of the common - cathode diode, as Figure 1 shown, a common - cathode diode generally has three pins, namely a cathode pin Q1 and two anode pins Q2, Q3. The common - cathode diode is generally electrically connected to a switching device. During the operation of the power conversion device, the frequent on - and - off of the switching device will cause the potential at both ends of the common - cathode diode to jump, generating parasitic inductances (such as Figure 1 L1, L2, and L3 in Figure 1 C1 and C2 in ). The parasitic inductances of the two anode pins Q2, Q3 will resonate with the parasitic capacitances. Therefore, high - frequency voltage oscillations will be generated at the two anode pins Q2, Q3, forming an interference source and causing electromagnetic compatibility (EMC) oscillation problems.

[0034] Based on this, in order to eliminate the electromagnetic compatibility oscillation problem of the common - cathode diode, the embodiments of the present application provide a packaging structure and a power conversion device. The packaging structure provided by the embodiments of the present application can be a common - cathode diode packaging structure or a common - anode diode packaging structure. Or, the packaging structure provided by the embodiments of the present application can also be other packaging structures including common - cathode (or common - anode) diodes, which are not limited herein. The packaging structure in the embodiments of the present application can be applied to power conversion devices such as charging piles, household photovoltaic devices, power stations, energy storage devices, inverters, etc. Of course, in some cases, the packaging structure in the embodiments of the present application can also be applied to other power conversion devices or other electronic devices.

[0035] In order to make the objectives, technical solutions, and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings.

[0036] It should be noted that the same reference numerals in the drawings of the present application represent the same or similar structures, and thus the repeated description thereof will be omitted. The words expressing positions and directions described in the present application are all illustrated by taking the drawings as examples, but can be changed as needed, and all the changes made are included in the protection scope of the present application. The drawings of the present application are only used to illustrate the relative position relationship and do not represent the actual proportion.

[0037] In the description of the present application, it should be noted that the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0038] Figure 2 It is a top view structural schematic diagram of the packaging structure provided by the embodiment of the present application. Figure 3 It is Figure 2 a schematic cross-sectional view at the dashed line AA' in Figure 4 It is Figure 2 an equivalent circuit schematic diagram of the packaging structure shown. In combination with Figures 2 to 4 , the packaging structure provided by the embodiment of the present application may include: a lead frame 11, a first diode chip 121, a second diode chip 122, a first bonding member 131, and a plastic package 14. Both the first diode chip 121 and the second diode chip 122 are located on the lead frame 11. Both the first diode chip 121 and the second diode chip 122 have a first electrode P1 and a second electrode P2. In the embodiment of the present application, the first electrode P1 is the anode of the diode chip, and the second electrode P2 is the cathode of the diode chip; alternatively, the first electrode P1 is the cathode of the diode chip, and the second electrode P2 is the anode of the diode chip. The first electrode P1 of the first diode chip 121 and the first electrode P1 of the second diode chip 122 are both welded to the surface of the lead frame 11. The lead frame 11 includes a conductive material. For example, the lead frame 11 may include metal materials such as copper, iron, and aluminum. The first electrode P1 of the first diode chip 121 is electrically connected to the first electrode P1 of the second diode chip 122 through the lead frame 11. The second electrode P2 of the first diode chip 121 and the second electrode P2 of the second diode chip 122 are bonded and connected through the first bonding member 131. The plastic package 14 wraps the first diode chip 121, the second diode chip 122, and the first bonding member 131.

[0039] In the encapsulation structure provided by the embodiments of the present application, the first electrode P1 of the first diode chip 121 and the first electrode P1 of the second diode chip 122 are electrically connected through the lead frame 11. The first electrode P1 can be the cathode or anode of the diode. Therefore, the encapsulation structure provided by the embodiments of the present application can be a common-cathode diode encapsulation structure, or it can also be a common-anode diode encapsulation structure. In the embodiments of the present application, by providing the first bonding member 131 in the encapsulation structure, the second electrode P2 of the first diode chip 121 and the second electrode P2 of the second diode chip 122 can be bonded and connected through the first bonding member 131. In this way, the parasitic inductance between the second electrodes P2 of the first diode chip 121 and the second diode chip 122 can be reduced, thereby suppressing the amplitude of the voltage oscillation between the second electrodes P2 of the first diode chip 121 and the second diode chip 122 and eliminating the electromagnetic compatibility oscillation problem. Moreover, the second electrode P2 of the first diode chip 121 and the second electrode P2 of the second diode chip 122 are bonded and connected through the first bonding member 131, which will not affect the connection relationship between the first diode chip 121 and the second diode chip 122 and other components, nor will it affect the overall performance of the encapsulation structure.

[0040] In addition, the plastic encapsulant 14 wraps the first diode chip 121, the second diode chip 122, and the first bonding member 131. The encapsulant 14 can play a role in protecting and fixing each component. Encapsulating the first bonding member 131 inside the plastic encapsulant 14 can prevent the first bonding member 131 from being exposed outside the encapsulation structure, which will not cause electrical safety and reliability problems and ensure that the encapsulation structure has high safety and reliability. The first bonding member 131 in the embodiments of the present application can be a bonding wire, a strip structure, a sheet structure, etc. Exemplarily, the strip structure can be an aluminum ribbon, and the sheet structure can be a copper clip. Exemplarily, the first bonding member 131 can include metal materials such as copper, aluminum, gold, silver, etc., or the first bonding member 131 can also include other conductive materials. During the manufacturing process, the first bonding member 131 can be manufactured by a bonding process or other processes, which is easy to be compatible with the manufacturing processes of other components in the encapsulation structure. For example, the first bonding wire 131 can be manufactured during the wire bond process in the front of line (FOL) of the encapsulation process. The manufacturing process has high feasibility and stability, and the manufacturing cost is low, with high manufacturability and supplyability.

[0041] In the embodiment of the present application, a first diode chip 121 and a second diode chip 122 are provided in the packaging structure, and the first diode chip 121 and the second diode chip 122 are arranged in parallel. That is to say, two diode chips arranged in parallel are provided in the packaging structure. In a specific implementation, more diode chips arranged in parallel can be provided in the packaging structure. Alternatively, other electronic components can also be provided in the packaging structure, which can be arranged according to actual needs. The packaging structure in the embodiment of the present application can adopt a transistor outline (TO), or the packaging structure can also adopt other packaging forms.

[0042] like Figure 2 and Figure 3 As shown, in the embodiment of the present application, the first electrode P1 of the first diode chip 121 may be located on the lower surface of the first diode chip 121, and the second electrode P2 of the first diode chip 121 may be located on the upper surface of the first diode chip 121. The first electrode P1 of the second diode chip 122 may be located on the lower surface of the second diode chip 122, and the second electrode P2 of the second diode chip 122 may be located on the upper surface of the second diode chip 122. Among them, the upper surface of the first diode chip 121 (or the second diode chip 122) is the surface of the first diode chip 121 (or the second diode chip 122) facing away from the lead frame 11, and the lower surface is the surface of the first diode chip 121 (or the second diode chip 122) close to the lead frame 11, that is, the description of "upper surface" and "lower surface" here is the same as Figure 3 The orientation of the views shown is consistent. In the implementation of the present application, the first electrode P1 and the second electrode P2 of the first diode chip 121 (or the second diode chip 122) are respectively arranged on the lower surface and the upper surface, so as to facilitate electrical connection with other components. In addition, the first electrodes P1 of the first diode chip 121 and the second diode chip 122 are located on the surface of the same side, and the second electrodes P2 are located on the surface of the same side, so as to facilitate electrical connection of the first electrodes P1 of the first diode chip 121 and the second diode chip 122, and electrical connection of the second electrodes P2 of the first diode chip 121 and the second diode chip 122. Since the lead frame 11 in the embodiment of the present application includes a conductive material, when the first diode chip 121 and the second diode chip 122 are installed to the corresponding positions on the surface of the lead frame 11, the electrical connection of the first electrodes P1 of the first diode chip 121 and the second diode chip 122 can be achieved. The first bonding component 131 is overlapped on the upper surfaces of the first diode chip 121 and the second diode chip 122 , so that the electrical connection between the second electrodes P2 of the first diode chip 121 and the second diode chip 122 can be achieved through the first bonding component 131 .

[0043] Of course, in some cases, the first electrode P1 and the second electrode P2 of the first diode chip 121 (or the second diode chip 122) can also be arranged on the surfaces on the same side. For example, the first electrode P1 and the second electrode P2 of the first diode chip 121 (or the second diode chip 122) can be arranged at different positions on the upper surface, and electrical connection with other components can also be achieved, which can be set according to the spatial layout of the package structure.

[0044] In some embodiments of the present application, the second electrodes of the first diode chip and the second diode chip can be electrically connected to different pins respectively. As Figure 2 and Figure 3 shown, the lead frame 11 may include: a separately arranged carrier plate 111, a first pin 112, and a second pin 113. The first diode chip 121 and the second diode chip 122 are located above the carrier plate 111, and the carrier plate 111 can play roles such as support and heat dissipation. The first electrode P1 of the first diode chip 121 and the first electrode P1 of the second diode chip 122 are both welded to the surface of the carrier plate 111. The second electrode P2 of the first diode chip 121 is electrically connected to the first pin 112, and the second electrode P2 of the second diode chip 122 is electrically connected to the second pin 113. The first pin 112 and the second pin 113 can play a role in signal connection, and the package structure can be electrically connected to other components through the first pin 112 and the second pin 113. In specific implementation, a part of the first pin 112 is wrapped by the encapsulant 14, and the other part is exposed outside the encapsulant 14. A part of the second pin 113 is wrapped by the encapsulant 14, and the other part is exposed outside the encapsulant 14. For example, when the first pin 112 and the second pin 113 are strip-shaped, the encapsulant 14 can wrap most of the first pin 112 and the second pin 113, leaving the ends of the first pin 112 and the second pin 113 exposed, facilitating the electrical connection of the package structure with other components through the first pin 112 and the second pin 113. Of course, in some cases, the encapsulant 14 can also completely wrap the first pin 112 and the second pin 113, and other connecting components can be used to lead out the first pin 112 and the second pin 113.

[0045] In a possible implementation manner, as Figure 2As shown in the figure, the encapsulation structure in the embodiment of the present application may further include: a second bonding member 132 and a third bonding member 133, and the encapsulant 14 wraps the second bonding member 132 and the third bonding member 133. The second electrode P2 of the first diode chip 121 is bonded to the first pin 112 through the second bonding member 132, and the second electrode P2 of the second diode chip 122 is bonded to the second pin 113 through the third bonding member 133. In specific implementation, the widths of the first bonding member 131, the second bonding member 132, and the third bonding member 133 may be substantially the same. Exemplarily, the first bonding member 131, the second bonding member 132, and the third bonding member 133 may all be bonding wires. During the manufacturing process, bonding wires made of metals with relatively high purity may be used to make the first bonding wire 131, the second bonding wire 132, and the third bonding wire 133. For example, bonding wires made of metal materials such as copper, aluminum, gold, and silver may be used. Of course, in some cases, other conductive materials may also be used to make the first bonding wire 131, the second bonding wire 132, and the third bonding wire 133. During the manufacturing process, the first bonding wire 131 may be made by using a wire bonding process. To improve the manufacturing efficiency, the first bonding wire 131, the second bonding wire 132, and the third bonding wire 133 may be made by using the same bonding process at one time.

[0046] Figure 5 Another top view structural schematic diagram of the encapsulation structure provided by the embodiment of the present application is shown in Figure 5 the figure. As shown, the width of the first bonding member 131 may be greater than the widths of the second bonding member 132 and the third bonding member 133. Exemplarily, the first bonding member 131 may be a strip structure. For example, it may be an aluminum ribbon, and the second bonding member 132 and the third bonding member 133 may be bonding wires.

[0047] Of course, in some cases, other bonding methods may also be used to make the first bonding member 131, which is not limited herein.

[0048] In another possible implementation, as shown in Figure 6 the figure, Figure 6Another top view structural schematic diagram of the encapsulation structure provided by the embodiments of the present application. The encapsulation structure in the embodiments of the present application may further include: a second bonding member 132, and the encapsulant 14 wraps the second bonding member 132. The first bonding member 131 is bonded to the second electrode P2 of the first diode chip 121, the second electrode P2 of the second diode chip 122, and the first pin 112. The second bonding member 132 is bonded to the second electrode P2 of the first diode chip 121, the second electrode P2 of the second diode chip 122, and the second pin 113. In specific implementation, when the second electrodes P2 of the first diode chip 121 and the second diode chip 122 are both located on the upper surface, the first bonding member 131 can be lapped on the upper surfaces of the first diode chip 121, the second diode chip 122, and the first pin 112, and the second bonding member 132 can be lapped on the upper surfaces of the first diode chip 121, the second diode chip 122, and the second pin 113.

[0049] Continue to refer to Figure 6 , the first bonding member 131 can be a folded linear integral structure, and the first bonding member 131 can be bent on the upper surface of the first diode chip 121. The second bonding member 132 can be a folded linear integral structure, and the second bonding member 132 can be bent on the upper surface of the second diode chip 122. In the manufacturing process, the first bonding member 131 can be fabricated by a bonding process. During the bonding process, three solder joints (the first solder joint, the second solder joint, and the third solder joint) can be set. The first solder joint can be located on the upper surface of the second diode chip 122, the second solder joint can be located on the upper surface of the first diode chip 121, and the third solder joint can be located on the upper surface of the first pin 112. The first bonding member 131 can be bent at the second solder joint without breaking the first bonding member 131, so as to achieve that the same first bonding member 131 is lapped on the upper surfaces of the first diode chip 121, the second diode chip 122, and the first pin 112, thereby obtaining the folded linear integral first bonding member 131. Similarly, the second bonding member 132 can be fabricated in a similar manner, which will not be elaborated here.

[0050] In another possible implementation manner, as Figure 7 shown, Figure 7Another top view structural schematic diagram of the encapsulation structure provided by the embodiment of the present application. The first bonding member 131 can be bonded to the second electrode P2 of the first diode chip 121, the second electrode P2 of the second diode chip 122, the first pin 112, and the second pin 113. The first bonding member 131 can be a folded linear integral structure, and the first bonding member 131 can be bent on the upper surfaces of the first diode chip 121 and the second diode chip 122. In a specific implementation, when the second electrodes P2 of the first diode chip 121 and the second diode chip 122 are both located on the upper surface, the first bonding member 131 can be lapped on the upper surfaces of the first diode chip 121, the second diode chip 122, the first pin 112, and the second pin 113. Exemplarily, the first bonding member 131 can be a sheet-like structure, and the fabricated folded linear first bonding member 131 can be bonded to the upper surfaces of the first diode chip 121, the second diode chip 122, the first pin 112, and the second pin 113. Alternatively, the first bonding member 131 can also be a bonding wire. During the bonding process, four solder joints can be set on the surfaces of the first diode chip 121, the second diode chip 122, the first pin 112, and the second pin 113 respectively, and the bonding wire can be bent at the second solder joint and the third solder joint without breaking the bonding wire, so as to achieve that the same bonding wire is lapped on the upper surfaces of the first diode chip 121, the second diode chip 122, the first pin 112, and the second pin 113, thereby obtaining the folded linear integral first bonding member 131.

[0051] In some other embodiments of the present application, the second electrodes of the first diode chip and the second diode chip can be electrically connected to the same pin. Figure 8 Another top view structural schematic diagram of the encapsulation structure provided by the embodiment of the present application, as Figure 8As shown in the figure, the lead frame 11 may include a separately provided carrier plate 111 and a first lead 112. The first electrodes P1 of the first diode chip 121 and the second diode chip 122 are both welded to the surface of the carrier plate 111, and the carrier plate 111 can play roles such as support and heat dissipation. The second electrodes P2 of the first diode chip 121 and the second diode chip 122 are both electrically connected to the first lead 112. The first lead 112 can play the role of signal connection, and the packaging structure can be electrically connected to other components through the first lead 112. In specific implementation, a part of the first lead 112 is wrapped by the encapsulant 14, and the other part is exposed outside the encapsulant 14. For example, when the first lead 112 is strip-shaped, the encapsulant 14 can wrap most of the first lead 112, leaving the end of the first lead 112 exposed, facilitating the electrical connection of the packaging structure to other components through the first lead 112. Of course, in some cases, the encapsulant 14 can also completely wrap the first lead 112, and other connecting components can be used to lead out the first lead 112.

[0052] In a possible implementation manner, as Figure 8 shown, the packaging structure in the embodiment of the present application may further include a second bonding member 132 and a third bonding member 133, and the encapsulant 14 wraps the second bonding member 132 and the third bonding member 133. The second electrode P2 of the first diode chip 121 and the first lead 112 are bonded and connected through the second bonding member 132, and the second electrode P2 of the second diode chip 122 and the first lead 112 are bonded and connected through the third bonding member 133. In specific implementation, the widths of the first bonding member 131, the second bonding member 132, and the third bonding member 133 may be substantially the same. Exemplarily, the first bonding member 131, the second bonding member 132, and the third bonding member 133 may all be bonding wires. In the manufacturing process, bonding wires made of metals with relatively high purity can be used to make the first bonding wire 131, the second bonding wire 132, and the third bonding wire 133. For example, bonding wires made of metal materials such as copper, aluminum, gold, and silver can be used. Of course, in some cases, other conductive materials can also be used to make the first bonding wire 131, the second bonding wire 132, and the third bonding wire 133. In the manufacturing process, the first bonding wire 131 can be made by using the wire bonding process. To improve the manufacturing efficiency, the first bonding wire 131, the second bonding wire 132, and the third bonding wire 133 can be made by using the same bonding process. Of course, in some cases, other bonding methods can also be used to make the first bonding member 131, and the width of the first bonding member 131 can also be greater than or less than the width of the second bonding member 132 (or the third bonding member 133), which can be set according to actual needs and is not limited herein.

[0053] In another possible implementation manner, as Figure 9 shown,Figure 9 Another top - view structural schematic diagram of the packaging structure provided by the embodiment of the present application. The first bonding member 131 is bonded to the second electrode P2 of the first diode chip 121, the second electrode P2 of the second diode chip 122, and the first pin 112. The first bonding member 131 is a one - piece structure in a zigzag shape, and the first bonding member 131 can be bent on the upper surfaces of the first diode chip 121 and the second diode chip 122 respectively. In specific implementation, when the second electrodes P2 of the first diode chip 121 and the second diode chip 122 are both located on the upper surface, the first bonding member 131 can be lapped on the upper surfaces of the first diode chip 121, the second diode chip 122, and the first pin 112. Exemplarily, the first bonding member 131 can be a sheet - like structure, and the fabricated zigzag - shaped first bonding member 131 can be bonded to the upper surfaces of the first diode chip 121, the second diode chip 122, and the first pin 112. Or, the first bonding member 131 can also be a bonding wire. During the bonding process, a solder joint can be set on the surfaces of the first diode chip 121 and the second diode chip 122 respectively, two solder joints can be set on the surface of the first pin 112, and the bonding wire can be bent at the second and third solder joints without breaking the bonding wire, so as to realize that the same bonding wire is lapped on the upper surfaces of the first diode chip 121, the second diode chip 122, and the first pin 112, thereby obtaining the one - piece first bonding member 131 in a zigzag shape.

[0054] The above - mentioned several ways of realizing the electrical connection of the second electrodes of the first diode chip and the second diode chip through the first bonding member are introduced in combination with the accompanying drawings. In specific implementation, each connecting member in the packaging structure can also have other implementation manners, which will not be exemplified one by one here.

[0055] Based on the same inventive concept, the embodiment of the present application also provides a power conversion device. The power conversion device in the embodiment of the present application can be devices such as a charging pile, a household photovoltaic device, a power station, an energy storage device, an inverter, etc. The power conversion device in the embodiment of the present application can include: any of the above - mentioned packaging structures and switching devices. Since the first bonding member is provided in the above - mentioned packaging structure in the embodiment of the present application, the second electrode of the first diode chip and the second electrode of the second diode chip can be bonded and connected through the first bonding member, reducing the parasitic inductance between the second electrodes of the first diode chip and the second diode chip, thereby suppressing the amplitude of the voltage oscillation between the second electrodes of the first diode chip and the second diode chip and eliminating the electromagnetic compatibility oscillation problem. Therefore, the power conversion device including the above - mentioned packaging structure will not be interfered by the electromagnetic compatibility oscillation, and the performance of the power conversion device is better.

[0056] Although the preferred embodiments of the present application have been described, those skilled in the art can make additional changes and modifications once they learn the basic creative concept. Therefore, the appended claims are intended to be construed as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0057] Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present application without departing from the spirit and scope of the embodiments of the present application. Thus, if these modifications and variations of the embodiments of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application also intends to include these modifications and variations.

Claims

1. An encapsulation structure, characterized in that, Comprising: A lead frame, said lead frame comprising a conductive material; A first diode chip and a second diode chip, both the first diode chip and the second diode chip having a first electrode and a second electrode, the first electrodes of the first diode chip and the second diode chip being welded to the surface of the lead frame, and the first electrodes of the first diode chip and the second diode chip being electrically connected through the lead frame; A first bonding member, the second electrodes of the first diode chip and the second diode chip being bonded and connected through the first bonding member; A plastic package, the plastic package encapsulating the first diode chip, the second diode chip, and the first bonding member.

2. The encapsulation structure according to claim 1, wherein, The lead frame comprises: a separately provided carrier plate, a first lead, and a second lead; The first electrode of the first diode chip is located on the lower surface of the first diode chip, and the second electrode of the first diode chip is located on the upper surface of the first diode chip; The first electrode of the second diode chip is located on the lower surface of the second diode chip, and the second electrode of the second diode chip is located on the upper surface of the second diode chip; The first electrodes of the first diode chip and the second diode chip are both welded to the surface of the carrier plate; The second electrode of the first diode chip is electrically connected to the first lead, and the second electrode of the second diode chip is electrically connected to the second lead; A part of the first lead is encapsulated by the plastic package, and another part is exposed outside the plastic package; A part of the second lead is encapsulated by the plastic package, and another part is exposed outside the plastic package.

3. The encapsulation structure according to claim 2, characterized in that, The first bonding member is bonded and connected to the second electrode of the first diode chip, the second electrode of the second diode chip, the first lead, and the second lead; The first bonding member is in a zigzag shape, and the first bonding member is bent on the upper surfaces of the first diode chip and the second diode chip respectively.

4. The encapsulation structure according to claim 2, wherein Further comprising: A second bonding member, the plastic package encapsulating the second bonding member; The first bonding member is bonded and connected to the second electrode of the first diode chip, the second electrode of the second diode chip, and the first lead; The second bonding member is electrically connected to the second electrode of the first diode chip, the second electrode of the second diode chip, and the second lead and is bonded and connected.

5. The encapsulation structure according to claim 4, characterized in that, The first bonding member is in a zigzag shape, and the first bonding member is bent on the upper surface of the first diode chip; the second bonding member is in a zigzag shape, and the second bonding member is bent on the upper surface of the second diode chip.

6. The encapsulation structure according to claim 2, wherein Further comprising: A second bonding member and a third bonding member, the plastic package encapsulating the second bonding member and the third bonding member; The second electrode of the first diode chip is bonded and connected to the first lead through the second bonding member, and the second electrode of the second diode chip is bonded and connected to the second lead through the third bonding member.

7. The encapsulation structure according to claim 1, characterized in that, The lead frame comprises: a separately provided carrier plate and a first lead; The first electrode of the first diode chip is located on the lower surface of the first diode chip, and the second electrode of the first diode chip is located on the upper surface of the first diode chip; The first electrode of the second diode chip is located on the lower surface of the second diode chip, and the second electrode of the second diode chip is located on the upper surface of the second diode chip; The first electrodes of the first diode chip and the second diode chip are both welded to the surface of the carrier plate; The second electrodes of the first diode chip and the second diode chip are both electrically connected to the first lead; A part of the first lead is wrapped by the encapsulant, and another part is exposed outside the encapsulant.

8. The encapsulation structure according to claim 7, characterized in that, The first bonding member is bonded to the second electrode of the first diode chip, the second electrode of the second diode chip and the first lead. The first bonding member is in a zigzag shape and is bent on the upper surfaces of the first diode chip and the second diode chip respectively.

9. The encapsulation structure according to any one of claims 1 to 8, characterized in that, The first bonding wire is a bonding wire, a strip structure or a sheet structure.

10. A power conversion device, characterized in that, Comprising: The packaging structure and the switching device according to any one of claims 1 to 9.

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