Power packaging structure, preparation method and electronic equipment

Abstract

The invention provides a power packaging structure and a preparation method thereof, and electronic equipment, the power packaging structure comprises a first substrate, at least one first power chip, N signal lead-out structures, a plastic package body, N hole-shaped slotting structures and M annular slotting structures, the N hole-shaped slotting structures and the M annular slotting structures are arranged in the plastic package body at intervals, and the hole-shaped slotting structures expose the corresponding signal lead-out structures. The annular slotting structure is the annular groove surrounding the plastic package body, so that the damage of the annular slotting structure to the plastic package body is small, the annular slotting structure can be used as a redundant structure to be arranged at a corresponding position, and the hole-shaped slotting structure can be used for position replacement with any annular slotting structure in different applications; therefore, the position of the corresponding signal leading-out structure is also replaced, and various applications of the same plastic package mold are realized. And the N hole-shaped slotting structures and the M annular slotting structures are distributed in the plastic package body at intervals, so that the surface of the plastic package body is scattered, and the deformation of the plastic package body when the plastic package body is heated is effectively inhibited.

Description

Technical Field

[0001] The present invention relates to the field of electronic circuits, and in particular to a power packaging structure and a preparation method thereof, and an electronic device. Background Art

[0002] First, power chip packaging is a key technology that connects power semiconductor devices (such as IGBTs, MOSFETs, and SiC / GaN devices) to external circuits and provides mechanical protection, heat dissipation, and electrical isolation. Its design must balance high power density, heat dissipation efficiency, reliability, and cost.

[0003] In the existing first power chip packaging structure with front-side pins, a plastic package groove is formed only at the position where the signal needs to be led out to expose the first substrate, and a corresponding signal lead-out structure is set in the groove to output the output signal of the first power chip to the outside.

[0004] However, the problem with the existing first power chip packaging structure with front-side pins is that the plastic package body is only slotted at the position of the signal lead-out structure, and the plastic package mold needs to be replaced when responding to packaging with different wiring or different topology structures, thereby increasing the packaging cost of different applications. Summary of the Invention

[0005] The present invention provides a power packaging structure and a preparation method and an electronic device to achieve multi-purpose use of one module, thereby reducing the packaging costs of different applications.

[0006] In order to solve the above technical problems, the technical solution of the present invention provides a power packaging structure, comprising:

[0007] a first substrate, wherein a circuit is provided on a top surface of the first substrate;

[0008] a first power chip, wherein the first power chip is fixed to the top surface of the first substrate and is electrically connected to the circuit;

[0009] N signal lead-out structures, each of which is disposed on a top surface of the first substrate, each of which is configured to lead out an output signal of the first power chip, where N is a positive integer and N ≥ 1;

[0010] A plastic package body, the plastic package body covering the top surface of the first substrate and the first power chip, a plurality of first slot structures being arranged in the plastic package body, the plurality of first slot structures being arranged at intervals from each other, the plurality of first slot structures including N hole-shaped slot structures and M ring-shaped slot structures, each of the hole-shaped slot structures exposing a corresponding one of the signal lead-out structures, M being a positive integer, and M ≥ 0.

[0011] Optionally, the power packaging structure is further provided with a plurality of second slotted structures, each of the second slotted structures corresponds to one of the first slotted structures, the second slotted structures are located on the corresponding first slotted structures, and the second slotted structures are connected to the corresponding first slotted structures, and the slot width of the second slotted structure is greater than the slot width of the first slotted structure.

[0012] Optionally, a shoulder is formed between the side wall surface of the second slotted structure and the top surface of the plastic package body, and a corner is formed between the side wall surface and the bottom surface of the second slotted structure, and both the shoulder and the corner are R-shaped chamfers.

[0013] Optionally, the height of the side wall is greater than or equal to 0.05 mm.

[0014] Optionally, the power packaging structure further includes: a second substrate and a second power chip, wherein a circuit is provided on a top surface of the second substrate; the second power chip is fixed to the top surface of the second substrate, and the second power chip is electrically connected to the circuit;

[0015] At least one of the N hole-shaped slot structures is located on the second substrate, and the signal lead-out structure is provided in the hole-shaped slot structure. The signal lead-out structure is used to lead out an output signal of the second power chip.

[0016] Optionally, the signal lead-out structure includes a signal needle vertically fixed to the bottom of the hole-shaped slot structure, and the top end of the signal needle protrudes relative to the plastic package body.

[0017] Optionally, the signal lead-out structure further includes a padding device, which is fixed on the top surface of the first substrate, and the signal needle is fixed to the padding device so that the signal needle is vertically fixed on the bottom of the hole-shaped slot structure.

[0018] Optionally, the raising device includes a pad, a needle seat and a sleeve, the bottom surface of the pad is fixed on the top surface of the first substrate or the second substrate, the top surfaces of all pads in different raising devices are flush, the bottom surface of the needle seat is fixed on the top surface of the pad, the bottom of the sleeve is fixed on the top surface of the needle seat, and the signal needle is inserted in the sleeve.

[0019] Optionally, an edge area of ​​the top surface of the pad is wrapped by the plastic packaging body, and a distance that the top surface of the pad is wrapped by the plastic packaging body is less than or equal to 1 mm.

[0020] Optionally, the plastic packaging body is wrapped in the side wall of the cushion block, and the top surface of the cushion block is free of the plastic packaging body.

[0021] Optionally, the roughness of the surface of the pad is less than or equal to 3.2.

[0022] Optionally, the power packaging structure further includes a sealing structure, and the sealing structure is used to insulate and seal the hole-shaped slot structure and the annular slot structure;

[0023] The power packaging structure also includes a power connection structure, which is fixed to the edge area of ​​the top surface of the first substrate and is located on both sides of the several slot structures along the length direction of the first substrate. Part of the power connection structure is encapsulated by the plastic encapsulation body, and part of the power connection structure extends out of the plastic encapsulation body.

[0024] Optionally, a distance between the bottom of the annular slot structure and the electrical connection component on the top surface of the first substrate is greater than or equal to a set threshold, and the set threshold is used to represent an electrical insulation requirement of the package.

[0025] The technical solution of the present invention also provides a method for preparing a power packaging structure, comprising:

[0026] Providing a first substrate, and disposing a circuit on a top surface of the first substrate;

[0027] Mounting a first power chip on the top surface of the first substrate, and electrically interconnecting the first power chip and the circuit on the top surface of the first substrate;

[0028] forming N signal lead-out structures on the top surface of the first substrate;

[0029] After forming the N signal lead-out structures, the bottom surface of the first substrate is placed in a lower plastic encapsulation mold, and an upper plastic encapsulation mold and the lower plastic encapsulation mold are combined. The upper plastic encapsulation mold is provided with a plurality of annular sleeve-shaped structures arranged at intervals along a direction toward the top surface of the first substrate, and N of the plurality of annular sleeve-shaped structures each correspond to one of the signal lead-out structures, and the N annular sleeve-shaped structures and the corresponding signal lead-out structure each form a closed annular sleeve space;

[0030] A plastic encapsulation material is injected between the lower plastic encapsulation mold and the upper plastic encapsulation mold to form a plastic encapsulation body, wherein the plastic encapsulation body covers the top surface of the first substrate and the first power chip. A plurality of first slot structures are formed in the plastic encapsulation body, and the plurality of first slot structures are spaced apart from each other. The plurality of first slot structures include N hole-shaped slot structures and M annular slot structures. Each hole-shaped slot structure exposes a corresponding signal lead-out structure. The outer contour of the hole-shaped slot structure is the same as that of the annular slot structure. M is a positive integer, and M≥0.

[0031] The technical solution of the present invention further provides an electronic device including the power packaging structure.

[0032] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0033] The power packaging structure provided by the technical solution of the present invention has several first slotted structures disposed within the plastic package, and the several first slotted structures include N hole-shaped slotted structures and M annular slotted structures. Each hole-shaped slotted structure is provided with a corresponding signal lead-out structure, each of which is used to lead out a type of output signal of the power signal mounted on the first substrate. Because the annular slotted structures are less destructive to the plastic package, the annular slotted structures can be disposed at a preset position as redundant structures. Furthermore, because the hole-shaped slotted structures can be replaced with any of the annular slotted structures in different power packaging applications based on wiring requirements or topology requirements, the signal lead-out structures corresponding to the hole-shaped slotted structures can also be replaced accordingly, thereby enabling multiple applications of the same plastic package mold and reducing the packaging costs of different applications. Furthermore, because the several first slotted structures are spaced apart within the plastic package, the surface of the plastic package is broken up, effectively suppressing deformation of the plastic package when heated, thereby improving the reliability of the power packaging structure.

[0034] Furthermore, a second slot structure is provided at the slot opening of each first slot structure, and the slot width of the second slot structure is greater than the slot width of the first slot structure, thereby facilitating avoiding damage to the plastic package body during the process of fixing the signal pin.

[0035] Furthermore, a shoulder is formed between the side wall surface of the second slotted structure and the top surface of the plastic package body, and a corner is formed between the side wall surface and the bottom surface of the second slotted structure. Both the shoulder and the corner are R-shaped chamfers, which is not only beneficial to the flow of the plastic package body and the demolding of the plastic package mold during the formation of the plastic package body, but also beneficial to the stress concentration of the plastic package body at the variable angle position inside the mold, avoiding the possible material shortage at the sharp angle position of the edge of the plastic package body after molding, resulting in poor losses, and further, during the use of the power packaging structure, it is beneficial to reduce the thermal stress concentration at the corners of the plastic package body.

[0036] Furthermore, the edge area of ​​the top surface of the pad is provided to be wrapped by the plastic package, thereby improving the insulation sealing and water vapor-proofing capability of the plastic package to the pad, thereby improving the reliability of the power packaging structure.

[0037] Furthermore, the distance between the bottom of the annular groove structure and the electrical connection component on the top surface of the first substrate is set to be greater than or equal to a set threshold, and the set threshold is used to characterize the electrical insulation requirements of the package, thereby improving the electrical insulation of the power packaging structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A top view of a power packaging structure provided by a first embodiment of the present invention;

[0039] Figure 2 for Figure 1 Schematic diagram of the cross-sectional structure along the BB' direction Figure 1 ;

[0040] Figure 3 It is a partial enlarged cross-sectional view of the positional relationship between the plastic package and the spacer;

[0041] Figure 4 for Figure 1 Schematic diagram of the cross-sectional structure along the BB' direction Figure 2 ;

[0042] Figure 5 A schematic cross-sectional view of a power packaging structure provided by a second embodiment of the present invention;

[0043] Figure 6 A schematic cross-sectional view of a power packaging structure provided by a third embodiment of the present invention;

[0044] Figure 7 A schematic cross-sectional view of a power packaging structure provided by a fourth embodiment of the present invention;

[0045] Figure 8 A top view of a power packaging structure provided by a fifth embodiment of the present invention;

[0046] Figure 9 A top view of a power packaging structure provided by a sixth embodiment of the present invention;

[0047] Figure 10 A top view of a power packaging structure provided by a seventh embodiment of the present invention;

[0048] Figures 11 to 17 Schematic diagram of the cross-sectional structure of each step of the method for preparing a power packaging structure provided by the eighth embodiment of the present invention. DETAILED DESCRIPTION

[0049] As described in the background art, the prior art only forms slots in the plastic package at the location of the signal lead-out structure. When packaging with different wiring or different topologies, the plastic package mold needs to be replaced, thereby increasing the packaging cost of different applications.

[0050] In view of this, the technical solution of the present invention provides a new power packaging structure. By disposing a plurality of first slot structures within a plastic package, including N hole-shaped slot structures and M annular slot structures, the same plastic package mold can be used for multiple applications, thereby reducing the packaging cost for different applications. Furthermore, because the plurality of first slot structures are spaced apart within the plastic package, the surface of the plastic package is broken up, effectively suppressing deformation of the plastic package when heated, thereby improving the reliability of the power packaging structure.

[0051] In order to make the above-mentioned objects, features and beneficial effects of the present invention more obvious and understandable, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention. The terms "first", "second", "third", "fourth", etc. (if any) in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way are interchangeable where appropriate, so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units that are not explicitly listed or inherent to these processes, methods, products or devices.

[0052] [First embodiment]

[0053] The power packaging structure includes a first substrate 10 , and a circuit is disposed on the top surface of the first substrate 10 .

[0054] a first power chip 20 , wherein the first power chip 20 is fixed to the top surface of the first substrate 10 and is electrically connected to the circuit;

[0055] N signal lead-out structures 30 are all arranged on the top surface of the first substrate 10 , and each of the signal lead-out structures 30 is used to lead out an output signal of the first power chip 20 , N is a positive integer, and N≥1.

[0056] A plastic package body 40, which covers the top surface of the first substrate 10 and the first power chip 20. A plurality of first slot structures are arranged in the plastic package body 40, and the plurality of first slot structures are arranged at intervals from each other. The plurality of first slot structures include N hole-shaped slot structures 51 and M annular slot structures 52. Each of the hole-shaped slot structures 51 exposes a corresponding signal lead-out structure 30. The outer contour of the hole-shaped slot structure 51 is the same as that of the annular slot structure 52. M is a positive integer, and M ≥ 0.

[0057] The annular slot structure 52 can be understood as a ring-shaped slot in the plastic package 40. The top view of the annular slot includes an outer ring and an inner ring, with a slot structure between the outer and inner rings. The area surrounded by the inner ring is filled with the material of the plastic package 40. Because the annular slot structure 52 does not slot the entire plastic package 40, it is less destructive to the plastic package 40, allowing it to be installed as a redundant structure in a corresponding position within the plastic package 40. The hole-shaped slot structure 51 can be understood as a hole-shaped slot in the plastic package 40. The top view of the hole-shaped slot includes an annular ring, and the area surrounded by the annular ring is a slot structure. Furthermore, because the hole-shaped slot structure 51 can be replaced with any of the annular slot structures 52 in different applications, the corresponding signal lead-out structure 30 within the hole-shaped slot structure 51 can also be replaced accordingly. That is, it can be understood that, among the first slotted structures arranged at intervals from each other, the first slotted structures at corresponding positions are set as the hole-shaped slotted structures 51 according to the application requirements, and the remaining first slotted structures are all set as the annular slotted structures 52. Since the topological structures of the first power chip 20 vary in different applications, the signal lead-out positions of the first power chip 20 also vary. Therefore, the original annular slotted structure 52 can be replaced with the hole-shaped slotted structure 51 according to the change in the signal lead-out position, and the signal lead-out structure 30 can be set in the replaced hole-shaped slotted structure 51, thereby achieving power packages with different topological structures based on the original slotted layout, and further realizing multiple applications of the same plastic encapsulation mold.

[0058] Furthermore, the outer ring of the annular slotted structure 52 and the hole ring of the hole-shaped slotted structure 51 are identical in size and shape, thereby facilitating position replacement of the annular slotted structure 52 and the hole-shaped slotted structure 51 .

[0059] Since power packaging combines and packages multiple materials together, and the thermal expansion coefficients of different materials are different, and since the plastic packaging process of power packaging and other processes after plastic packaging all involve a heating process stage, the epoxy molding compound located on the upper part of the plastic packaging body and the substrate exposed at the lower part of the plastic packaging body will naturally differ when deformed by thermal expansion. Based on the above problems, the present embodiment provides the plurality of first slotted structures spaced apart within the plastic packaging body 40 to break up the surface of the plastic packaging body 40, thereby facilitating the adjustment of the deformation of the plastic packaging body when heated, thereby improving the reliability of the power packaging structure.

[0060] Furthermore, the shapes of the hole ring of the hole-shaped slotted structure 51 and the outer and inner rings of the annular slotted structure include at least one of a circle and a square, which is not limited here.

[0061] Figure 1 A top view of the power packaging structure provided by the first embodiment of the present invention.

[0062] Please refer to Figure 1 In this embodiment, the first slot structures are divided into three columns. The first slot structures in each column are arranged at intervals along the first direction BB'. The three columns of first slot structures are arranged at intervals along the second direction AA'. The number of first slot structures in each column is four. The position and number of the hole-shaped slot structures in each column are not uniform. The first direction BB' and the second direction AA' are perpendicular to each other. Figure 1 The solid dots in the figure are used to represent the hole-shaped slotted structure 51. Figure 1 The hollow ring in is used to represent the annular slotted structure 52 .

[0063] In this embodiment, the first substrate 10 comprises a ceramic copper-clad substrate. A circuit is etched on the top surface of the ceramic copper-clad substrate. The circuit is formed by etching grooves in the copper clad surface of the substrate, dividing the copper clad surface of the substrate. This circuit can be understood as etching predetermined grooves in the copper clad surface of the first substrate 10 to form the circuit. The specific pattern of the circuit is related to the topological structure of the first power chip 20 in the actual package and is not limited here.

[0064] Furthermore, since the first substrate 10 is a ceramic copper-clad substrate, the method for attaching the first power chip 20 to the corresponding substrate includes direct copper bonding. Of course, since the method for attaching the first power chip 20 to the corresponding substrate is related to the material of the substrate and the actual application scenario, it is not limited here.

[0065] In one embodiment, the ceramic copper-clad substrate is copper-clad on both the top and bottom surfaces to enhance the heat dissipation capability of the final power package structure. The copper cladding on the bottom surface of the ceramic copper-clad substrate can be either fully copper-clad or copper-grooved, which is not limited here.

[0066] In one embodiment, the type of the ceramic copper-clad substrate includes at least one of a direct bonded copper ceramic substrate (DBC), an active metal brazing ceramic substrate (AMB), and a direct plated copper ceramic substrate (DPC). Of course, in addition to the ceramic copper-clad substrate, the first substrate 10 may also include a metal substrate, a resin substrate, etc., which is not limited here. For ease of explanation, the first substrate 10 in this embodiment refers to a ceramic copper-clad substrate.

[0067] In this embodiment, the first power chip 20 includes at least one or more of a MOS transistor, an IGBT transistor, a diode, and a thyristor. Since the number and type of the first power chips 20 are related to the specific topology, they are not limited herein. Since electrical connection between the power chip and the circuit on the substrate is a conventional technique in the art, a detailed description thereof is omitted here.

[0068] Figure 2 for Figure 1 Schematic diagram of the cross-sectional structure along the BB' direction Figure 1 .

[0069] Please refer to Figure 2During the formation of the signal lead-out structure 30, the signal pin 31 is first positioned within the pin header, with the majority of the pin 31 inserted into the header, leaving only the tail end of the pin 31 exposed for attachment to the bottom of the corresponding hole-shaped slot structure 51. Because the pin header is significantly wider than the signal pin 31, there is a risk that the pin header could come into contact with the plastic package 40 during the downward movement of the pin 31 for attachment, potentially damaging a portion of the plastic package 40. In order to solve the above problem, in one embodiment, the power packaging structure is further provided with a plurality of second slotted structures 70, each of the second slotted structures 70 corresponds to one first slotted structure, the second slotted structure 70 is located on the corresponding first slotted structure, and is connected to the corresponding first slotted structure, and the slot width of the second slotted structure 70 is greater than the slot width of the first slotted structure. It can be understood that, on the basis of each of the hole-shaped slotted structure 51 and each of the annular slotted structure 52, an additional wider slotted structure is provided to serve as an accommodating space for the pin head during the fixing process of the signal pin 31, thereby avoiding contact between the pin head and the plastic package body 40 and damaging the plastic package body 40.

[0070] Furthermore, a shoulder is formed between the side wall surface of the second slotted structure 70 and the top surface of the plastic package 40, and a corner is formed between the side wall surface and the bottom surface of the second slotted structure 70. Both the shoulder and the corner are R-shaped chamfers, which not only facilitates the flow of the plastic package and the demolding of the plastic package mold during the formation of the plastic package, but also facilitates the stress concentration of the plastic package at the variable angle position inside the mold, avoiding the possible material shortage at the sharp edge position after the plastic package is formed, resulting in poor losses, and thus helping to reduce the thermal stress concentration at the corners of the plastic package during the use of the power packaging structure. Furthermore, the height of the side wall is greater than or equal to 0.05 mm. Of course, the height of the side wall can be adjusted according to actual needs and is not limited here.

[0071] Please continue to refer to Figure 2 In this embodiment, the signal lead-out structure 30 includes a padding device 32 and a signal needle 31. The bottom surface of the padding device 32 is fixed on the top surface of the first substrate 10; the signal needle 31 is vertically fixed on the top surface of the padding device 32.

[0072] Please continue to refer to Figure 2 In this embodiment, the heightening device 32 includes a pad 321. The bottom surface of the pad 321 is fixed to the top surface of the first substrate 10, and the signal pin 31 is fixed to the top surface of the pad 321. The top and bottom surfaces of the pad 321 are opposite to each other. The top surface of the pad 321 can be understood as the top surface of the heightening device 32.

[0073] It should be noted that the thickness of the pads 321 corresponding to the different height-raising components 32 is the same, ensuring that the heights of the signals drawn from different signal pins are at the same level. Furthermore, to ensure that the output signals corresponding to the first power chip 20 can be externally led through the signal lead-out structure 30, the pads 321 must be made of a conductive material. For example, the material of the pads 321 is copper or other conductive metal, which is not limited here.

[0074] Figure 3 It is a partial enlarged cross-sectional view of the positional relationship between the plastic package and the gasket.

[0075] Please refer to Figure 3 In a preferred embodiment, the edge of the top surface of the spacer 321 is wrapped by the plastic encapsulation body 40, thereby improving the insulation sealing and water vapor protection of the spacer 321 by the plastic encapsulation body 40, thereby improving the reliability of the power packaging structure. Specifically, the distance between the top surface of the spacer and the plastic encapsulation body is less than or equal to 1 mm.

[0076] Furthermore, the surface roughness Ra of the pad 321 is less than or equal to 3.2. Of course, the surface roughness of the pad 321 can also be adaptively adjusted according to actual applications, and is not limited here.

[0077] In this embodiment, the signal pin 31 includes at least one of a square cross-section pin, a circular cross-section pin, a fisheye pin, and a non-fisheye pin, without limitation herein. Furthermore, methods for securing the signal pin 31 include at least soldering, ultrasonic welding, laser welding, and other suitable methods, without limitation herein.

[0078] Figure 4 for Figure 1 Schematic diagram of the cross-sectional structure along the BB' direction Figure 2 .

[0079] Please refer to Figure 4 In this embodiment, the power packaging structure further includes a sealing structure 200 , and the sealing structure 200 is used to insulate and seal the hole-shaped slot structure 51 and the annular slot structure 52 .

[0080] The power packaging structure also includes a power connection structure 160, which is fixed to the edge area of ​​the top surface of the first substrate 10 and is located on both sides of the several slot structures along the length direction of the first substrate 10. Part of the power connection structure 160 is encapsulated by the plastic encapsulation body 40, and part of the power connection structure 160 extends out of the plastic encapsulation body 40.

[0081] In this embodiment, the distance between the bottom of the annular slot structure 52 and the electrical connection component fixed on the top surface of the first substrate 10 is greater than or equal to a set threshold, thereby improving the electrical insulation of the power packaging structure. The set threshold is used to characterize the electrical insulation requirements of the package. The specific size of the set threshold is determined by the electrical insulation material and is not limited here. Specifically, the electrical connection component includes at least a lead, a power chip, etc. For example, if the lead is the highest, the distance between the bottom of the annular slot structure 52 and the lead is greater than or equal to the set threshold.

[0082] In summary, the power packaging structure provided in this embodiment has N hole-shaped slotted structures disposed within the plastic package, and each hole-shaped slotted structure is provided with a corresponding signal lead-out structure. The signal lead-out structures are used to externally lead out a type of output signal of the power signal mounted on the first substrate. M annular slotted structures are also disposed within the plastic package. Because the annular slotted structures are less destructive to the plastic package, the annular slotted structures can be disposed at a preset position as redundant structures. Furthermore, because the hole-shaped slotted structures can be replaced with any of the annular slotted structures in different power packaging applications based on wiring requirements or topology requirements, the signal lead-out structures corresponding to the hole-shaped slotted structures can also be replaced accordingly, thereby enabling multiple applications of the same plastic package mold and reducing the packaging costs of different applications. Furthermore, because the N hole-shaped slotted structures and the M annular slotted structures are spaced apart within the plastic package, the surface of the plastic package is broken up, effectively suppressing deformation of the plastic package when heated, thereby improving the reliability of the power packaging structure.

[0083] Furthermore, a second slot structure is provided at the slot opening of each first slot structure, and the slot width of the second slot structure is greater than the slot width of the first slot structure, thereby facilitating avoiding damage to the plastic package body during the process of fixing the signal pin.

[0084] Furthermore, a shoulder is formed between the side wall surface of the second slotted structure and the top surface of the plastic package body, and a corner is formed between the side wall surface and the bottom surface of the second slotted structure. Both the shoulder and the corner are R-shaped chamfers, which is not only beneficial to the flow of the plastic package body and the demolding of the plastic package mold during the formation of the plastic package body, but also beneficial to the stress concentration of the plastic package body at the variable angle position inside the mold, avoiding the possible material shortage at the sharp angle position of the edge of the plastic package body after molding, resulting in poor losses, and further, during the use of the power packaging structure, it is beneficial to reduce the thermal stress concentration at the corners of the plastic package body.

[0085] Furthermore, the edge area of ​​the top surface of the pad is provided to be wrapped by the plastic package, thereby improving the insulation sealing and water vapor-proofing capability of the plastic package to the pad, thereby improving the reliability of the power packaging structure.

[0086] Furthermore, the distance between the bottom of the annular groove structure and the electrical connection component on the top surface of the first substrate is set to be greater than or equal to a set threshold, and the set threshold is used to characterize the electrical insulation requirements of the package, thereby improving the electrical insulation of the power packaging structure.

[0087] [Second embodiment]

[0088] Figure 5 This is a schematic cross-sectional view of a power packaging structure provided by a second embodiment of the present invention.

[0089] This embodiment is a modified embodiment of the first embodiment. Please refer to Figure 5 The difference between this embodiment and the first embodiment is that the power packaging structure further includes a second substrate 60 and a second power chip 21. The bottom surface of the second substrate 60 is fixed to the top surface of the first substrate 10, and the top surface of the second substrate 60 is provided with a circuit; the second power chip 21 is fixed to the top surface of the second substrate 60, and the second power chip 21 is electrically connected to the circuit, and the top surface and bottom surface of the second substrate 60 are opposite to each other.

[0090] At least one of the N hole-shaped slot structures 51 is located on the second substrate 60 , and the signal lead-out structure 30 is provided in the hole-shaped slot structure 51 . The signal lead-out structure 30 is used to lead out an output signal of the second power chip 21 .

[0091] Furthermore, the second substrate 60 comprises a stack of multiple active metal brazing substrates, each layer of which is soldered together. Of course, the second substrate 60 may include, in addition to the active metal brazing substrate, a direct-bonded copper-ceramic substrate or a direct-copper-plated copper-ceramic substrate, without limitation.

[0092] Furthermore, the second power chip 21 can be a second type of chip different from the first power chip 20, such as a gate-level resistor chip or another type of power chip. The second power chip 21 and the first power chip 20 may differ in parameter characteristics and materials, but may be packaged together. For example, a silicon carbide chip and a silicon chip may be packaged together.

[0093] In this embodiment, the method of mounting the second power chip 21 on the top surface of the second substrate 60 is the same as that of the first power chip in the first embodiment, and is not described herein in detail.

[0094] In this embodiment, since the top surfaces of the first substrate 10 and the second substrate 60 are at different levels, to ensure that the top surfaces of the different height-raising devices 33 are at the same level, the height-raising devices 33 fixed to the top surfaces of the different substrates need to be highly adaptable. The specific adjustment method is to thicken the spacer 331 located on the top surface of the first substrate 10 and thin the spacer 331 located on the top surface of the second substrate 60 to ensure that the top surfaces of the spacer 331 located on the top surface of the first substrate 10 and the spacer 331 located on the top surface of the second substrate 60 are at the same level.

[0095] In addition to the second substrate 60 and the second power chip 21, another difference between this embodiment and the first embodiment is that the heightening device 33, in addition to the cushion block 331, further includes a needle holder 332 and a sleeve 333. The bottom surface of the needle holder 332 is fixed to the top surface of the cushion block 331, and the base of the sleeve 333 is fixed to the top surface of the needle holder 332. The signal pin 31 is inserted into the sleeve 333 for fixation. The top and bottom surfaces of the needle holder 332 face each other.

[0096] [Third embodiment]

[0097] Figure 6 This is a schematic cross-sectional view of a power packaging structure provided by a third embodiment of the present invention.

[0098] This embodiment is a modified embodiment of the first embodiment. Please refer to Figure 6 This embodiment differs from the first embodiment in that the heightening device does not include the spacer block, but only includes a needle holder and a sleeve. The bottom surface of the needle holder 342 is fixed to the top surface of the first substrate 10, and the base of the sleeve 343 is fixed to the top surface of the needle holder 342. The signal pin 31 is inserted into the sleeve 343, and the top and bottom surfaces of the needle holder 342 face each other.

[0099] [Fourth embodiment]

[0100] Figure 7 This is a schematic cross-sectional view of a power packaging structure provided by a fourth embodiment of the present invention.

[0101] This embodiment is a modified embodiment of the first embodiment. Please refer to Figure 7 The difference between this embodiment and the first embodiment is that the signal lead-out structure 30 does not have the padding device, but only has a signal pin 31 vertically fixed to the bottom of the hole-shaped slot structure 51. It can be understood that in this embodiment, the signal pin 31 is directly fixed to the top surface of the first substrate 10, and the top of the signal pin 31 protrudes relative to the plastic package body 40.

[0102] [Fifth embodiment]

[0103] Figure 8 A top view of a power packaging structure provided by a fifth embodiment of the present invention.

[0104] This embodiment is a modified embodiment of the first embodiment. Please refer to Figure 8 The difference between this embodiment and the first embodiment is that the arrangement of the first slotted structure is changed to an I-shaped arrangement. The I-shaped arrangement of the first slotted structure includes a third array 100, a fourth array 110, and a fifth array 120. The third array 100 and the fifth array 120 are both arranged along the first direction BB', and the fourth array 110 is arranged along the second direction AA'. The fourth array 110 is arranged between the third array 100 and the fifth array 120, and the first end of the fourth array 110 is adjacent to the midpoint of the third array 100, and the second end of the fourth array 110 is adjacent to the midpoint of the fifth array 120. In which, the third array 100 includes two rows of the first slotted structures uniformly arranged along the first direction BB', the fourth array 110 includes two columns of the first slotted structures uniformly arranged along the second direction AA', and the fifth array 120 includes two rows of the first slotted structures uniformly arranged along the first direction BB', and the number of the first slotted structures in the third array 100 is the same as that in the fifth array 120, and different from that in the fourth array 110.

[0105] [Sixth embodiment]

[0106] Figure 9 A top view of a power packaging structure provided by a sixth embodiment of the present invention.

[0107] This embodiment is a modified embodiment of the first embodiment. Please refer to Figure 9 This embodiment differs from the first embodiment in that the first slotted structures are arranged in an H-shaped arrangement. The H-shaped arrangement of the first slotted structures includes a sixth array 130, a seventh array 140, and an eighth array 150. The sixth array 130 and the eighth array 150 are arranged along the second direction AA', and the seventh array 140 is arranged along the first direction BB'. The seventh array 140 is disposed between the sixth array 130 and the eighth array 150. The sixth array 130 includes two columns of the first slotted structures evenly spaced along the second direction AA', the seventh array 140 includes two rows of the first slotted structures evenly spaced along the first direction BB', and the eighth array 150 includes three columns of the first slotted structures evenly spaced along the second direction AA'. Furthermore, the number of first slotted structures in each of the sixth array 130, the seventh array 140, and the eighth array 150 is different.

[0108] It should be noted that the arrangements of the first slot structures in the first, fifth, and sixth embodiments are merely three specific examples. The actual arrangement and number of the first slot structures are generally determined by the area of ​​the package structure and are not limited here. Furthermore, in actual applications, the number of hole-shaped slot structures 51 in the first slot structure is generally between 4 and 12, and the number and distribution of the hole-shaped slot structures 51 are also related to the topological structure of the actual application and are not limited here.

[0109] [Seventh embodiment]

[0110] Figure 10 A top view of a power packaging structure provided by a seventh embodiment of the present invention.

[0111] This embodiment is a modified embodiment of the first embodiment. Please refer to Figure 10 The difference between this embodiment and the first embodiment is that M is equal to 0, the annular slot structure 52 does not exist in the plastic package body 40, and all the first slot structures are the hole-shaped slot structures 51 for signal extraction of the power signal.

[0112] [Eighth embodiment]

[0113] This embodiment provides a method for preparing a power packaging structure, which includes the following steps.

[0114] A first substrate is provided, and a circuit is disposed on a top surface of the first substrate.

[0115] A first power chip is mounted on the top surface of the first substrate, and the first power chip and the circuit on the top surface of the first substrate are electrically interconnected.

[0116] N signal lead-out structures are formed on the top surface of the first substrate.

[0117] After forming the N signal lead-out structures, after the first power chip and the circuit on the top surface of the first substrate are electrically interconnected, the bottom surface of the first substrate is placed in the plastic encapsulation lower mold, and the plastic encapsulation upper mold and the plastic encapsulation lower mold are combined. The plastic encapsulation upper mold is provided with a plurality of spaced annular sleeve-shaped structures 171 along the direction toward the top surface of the first substrate, and N of the plurality of annular sleeve-shaped structures 171 correspond to one of the signal lead-out structures, and the N annular sleeve-shaped structures 171 form a closed annular sleeve space with the corresponding signal lead-out structure.

[0118] A plastic encapsulation material is injected between the lower plastic encapsulation mold and the upper plastic encapsulation mold to form a plastic encapsulation body, wherein the plastic encapsulation body covers the top surface of the first substrate and the first power chip. A plurality of first slot structures are formed in the plastic encapsulation body, and the plurality of first slot structures are spaced apart from each other. The plurality of first slot structures include N hole-shaped slot structures and M annular slot structures. Each hole-shaped slot structure exposes a corresponding signal lead-out structure. The outer contour of the hole-shaped slot structure is the same as that of the annular slot structure. M is a positive integer, and M≥0.

[0119] The following is a detailed description of the method for preparing the power packaging structure provided by the embodiment of the present invention.

[0120] Figures 11 to 17 Schematic diagram of the cross-sectional structure of each step of the method for preparing a power packaging structure provided by the eighth embodiment of the present invention.

[0121] A first substrate 10 is provided, and a circuit is disposed on a top surface of the first substrate 10 .

[0122] Specifically, the structure of the first substrate 10 and the circuit arrangement on the top surface of the first substrate 10 are described in detail in the above embodiment of the power packaging structure, and will not be repeated here.

[0123] Please refer to Figure 11 , a first power chip 20 is mounted on the top surface of the first substrate 10 , and the first power chip 20 and the circuit on the top surface of the first substrate 10 are electrically interconnected.

[0124] Specifically, the method of mounting the first power chip 20 and the top surface of the first substrate 10 includes at least one of soldering and silver sintering.

[0125] Specifically, the electrical interconnection between the first power chip 20 and the circuit on the top surface of the first substrate 10 includes at least any one of a wire bonding process, a ribbon bonding process, a copper clip connection process, and a flexible PCB connection process.

[0126] N signal lead-out structures 30 are formed on the top surface of the first substrate 10. For specific steps, please refer to Figure 12 and Figure 13

[0127] Please refer to Figure 12 , a pad 351 is mounted on the top surface of the first substrate 10 .

[0128] Specifically, the method of mounting the pad 351 on the top surface of the first substrate 10 includes at least one of soldering and silver sintering.

[0129] Please refer to Figure 13, fix the needle seat 352 and the sleeve 353 on the top surface of the cushion block 351.

[0130] Specifically, securing the needle hub 352 and sleeve 353 to the top surface of the cushion block 351 includes securing the bottom surface of the needle hub 352 to the surface of the cushion block 351, and securing the base of the sleeve 353 to the top surface of the needle hub 352, with the top and bottom surfaces of the needle hub 352 facing each other. The method for securing the bottom surface of the needle hub 352 to the top surface of the cushion block 351 and the method for securing the base of the sleeve 353 to the top surface of the needle hub 352 both include at least one of soldering, ultrasonic welding, and laser welding.

[0131] Please continue to refer to Figure 13 While fixing the needle seat 352 and the sleeve 353 on the top surface of the pad 351, it also includes: fixing the power connection structure 160 on the edge area of ​​the top surface of the first substrate 10 and on both sides of the several slot structures along the length direction of the first substrate 10.

[0132] It should be noted that there is no clear order for forming N signal lead-out structures 30 on the top surface of the first substrate 10 and electrically interconnecting the first power chip 20 and the circuit on the top surface of the first substrate 10, and no limitation is made here.

[0133] Please refer to Figure 14 After forming the N signal lead-out structures 30, the bottom surface of the first substrate 10 is placed in a plastic encapsulation lower mold, and the plastic encapsulation upper mold and the plastic encapsulation lower mold are combined. The plastic encapsulation upper mold is provided with a plurality of annular sleeve-shaped structures 171 arranged at intervals along the direction toward the top surface of the first substrate 10, and N of the plurality of annular sleeve-shaped structures 171 correspond to one of the signal lead-out structures 30, and the N annular sleeve-shaped structures 171 form a closed annular sleeve space with the corresponding signal lead-out structure 30.

[0134] Specifically, the shape of the annular sleeve structure 171 includes at least one of a circle and a square, which is not limited here.

[0135] Specifically, the annular sleeve-like structure 171 further includes a base, the bottom surface of which is disposed on the top surface of the base, which is disposed on the surface of the upper molding mold. The area of ​​the annular sleeve-like structure 171 is smaller than that of the base, thereby forming a second slotted structure 70 connected to the first slotted structure in a direction away from the top surface of the first substrate 10, and the slot width of the second slotted structure 70 is greater than the slot width of the first slotted structure. Furthermore, the angle formed by the sidewall of the base and the surface of the upper molding mold is an R-shaped chamfer, and the angle formed by the sidewall of the base and the top surface of the base is also an R-shaped chamfer, resulting in both the shoulder and the corner of the second slotted structure 70 being R-shaped chamfers. The shoulder is formed by the sidewall of the second slotted structure 70 and the top surface of the molding body 40, and the corner is formed by the sidewall and the bottom surface of the second slotted structure 70. The respective beneficial effects of providing the second slot structure 70 and providing the shoulder and the corner with R-shaped chamfers have been described in detail in the above embodiment of the power packaging structure and will not be repeated here.

[0136] Please continue to refer to Figure 14 , a plastic encapsulation body 40 material is injected between the plastic encapsulation lower mold and the plastic encapsulation upper mold to form a plastic encapsulation body 40, the plastic encapsulation body 40 covers the top surface of the first substrate 10 and the first power chip 20, and a plurality of first slot structures are formed in the plastic encapsulation body 40, the plurality of first slot structures are spaced apart from each other, the plurality of first slot structures include N hole-shaped slot structures 51 and M annular slot structures 52, each of the hole-shaped slot structures 51 exposes a corresponding signal lead-out structure 30, the outer contour of the hole-shaped slot structure 51 is the same as that of the annular slot structure 52, M is a positive integer, and M≥0.

[0137] Specifically, the hole-shaped slotted structure 51 is formed by the annular sleeve-shaped structure 171 of the plastic packaging upper mold and the pad 351 to form a closed annular sleeve space, and the annular slotted structure 52 is directly formed by the annular sleeve-shaped structure 171 of the plastic packaging upper mold. Figure 14 In the cross-sectional structural diagram shown, the size of the annular sleeve structure 171 of the plastic packaging upper mold is the same as the size of the pad, and both are a1. Figure 14 The plastic encapsulation body shown only wraps the side wall of the pad, and does not cover the top surface of the pad. In other embodiments, the size b1 of the annular sleeve structure 171 of the plastic encapsulation upper mold is smaller than the size c1 of the pad, such as Figure 15 Therefore Figure 15The plastic package shown not only wraps the side walls of the pad, but also wraps the edge area of ​​the top surface of the pad, thereby improving the insulation sealing and water vapor protection capabilities of the plastic package to the pad, thereby improving the reliability of the power packaging structure.

[0138] Please refer to Figure 16 After forming the plastic package body 40 , the method further includes: inserting the signal pin 36 into the sleeve 353 through the pin head 33 to form an external electrical connection.

[0139] Specifically, the shape of the signal pin 36 has been described in detail in the embodiment of the power packaging structure above, and will not be repeated here.

[0140] Furthermore, before inserting the signal pin 36 into the sleeve 353, the process further includes: removing the oxide layer, dirt, and plastic material overflow on the surface of the pad 351. The removal method includes at least one of laser processing and glass fiber pen erasing.

[0141] Please refer to Figure 17 After inserting the signal pin 36 into the sleeve 353, the process further includes injecting a potting compound into all first slots to form a sealed structure 200. The potting compound includes epoxy resin, silicone gel, or other suitable liquid adhesive. The potting compound insulates and seals the lead plane of the signal pin 36 while preventing moisture and dust from entering the first slots.

[0142] Ninth embodiment

[0143] This embodiment provides an electronic device, including the power packaging structure according to any one of the first to seventh embodiments.

[0144] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A power packaging structure, characterized in that: include: a first substrate, wherein a circuit is provided on a top surface of the first substrate; a first power chip, wherein the first power chip is fixed to the top surface of the first substrate and is electrically connected to the circuit; N signal lead-out structures, each of which is disposed on a top surface of the first substrate, each of which is configured to lead out an output signal of the first power chip, where N is a positive integer and N ≥ 1; A plastic package body, the plastic package body covering the top surface of the first substrate and the first power chip, a plurality of first slot structures being arranged in the plastic package body, the plurality of first slot structures being arranged at intervals from each other, the plurality of first slot structures including N hole-shaped slot structures and M ring-shaped slot structures, each of the hole-shaped slot structures exposing a corresponding one of the signal lead-out structures, M being a positive integer, and M ≥ 0.

2. The power packaging structure according to claim 1, wherein: The power packaging structure is also provided with a plurality of second slot structures, each of the second slot structures corresponds to one first slot structure, the second slot structure is located on the corresponding first slot structure, and the second slot structure is connected to the corresponding first slot structure, and the slot width of the second slot structure is greater than the slot width of the first slot structure.

3. The power packaging structure according to claim 2, wherein: A shoulder is formed between the side wall surface of the second slotted structure and the top surface of the plastic package body, and a corner is formed between the side wall surface and the bottom surface of the second slotted structure. Both the shoulder and the corner are R-shaped chamfers.

4. The power packaging structure according to claim 3, characterized in that: The height of the side wall is greater than or equal to 0.05 mm.

5. The power packaging structure according to claim 1, wherein: The power packaging structure further includes: a second substrate and a second power chip, wherein a circuit is provided on a top surface of the second substrate; the second power chip is fixed to the top surface of the second substrate, and the second power chip is electrically connected to the circuit; At least one of the N hole-shaped slot structures is located on the second substrate, and the signal lead-out structure is provided in the hole-shaped slot structure. The signal lead-out structure is used to lead out an output signal of the second power chip.

6. The power packaging structure according to claim 5, characterized in that: The signal lead-out structure includes a signal pin vertically fixed to the bottom of the hole-shaped slot structure, and the top of the signal pin protrudes relative to the plastic package body.

7. The power packaging structure according to claim 6, characterized in that: The signal lead-out structure further includes a padding device fixed on the top surface of the first substrate. The signal needle is fixed to the padding device so that the signal needle is vertically fixed on the bottom of the hole-shaped slot structure.

8. The power packaging structure according to claim 7, wherein: The raising device includes a pad, a needle seat and a sleeve. The bottom surface of the pad is fixed on the top surface of the first substrate or the second substrate. The top surfaces of all pads in different raising devices are flush. The bottom surface of the needle seat is fixed on the top surface of the pad, the bottom of the sleeve is fixed on the top surface of the needle seat, and the signal needle is inserted in the sleeve.

9. The power packaging structure according to claim 8, characterized in that: The edge area of ​​the top surface of the pad is wrapped by the plastic packaging body, and the distance that the top surface of the pad is wrapped by the plastic packaging body is less than or equal to 1 mm.

10. The power packaging structure according to claim 8, characterized in that: The side wall of the cushion block is wrapped by the plastic packaging body, and the top surface of the cushion block is free of the plastic packaging body.

11. The power packaging structure according to claim 8, characterized in that: The roughness of the surface of the pad is less than or equal to 3.

2.

12. The power packaging structure according to claim 1, wherein: The power packaging structure further includes a sealing structure, which is used to insulate and seal the hole-shaped slot structure and the annular slot structure; The power packaging structure also includes a power connection structure, which is fixed to the edge area of ​​the top surface of the first substrate and is located on both sides of the several slot structures along the length direction of the first substrate. Part of the power connection structure is encapsulated by the plastic encapsulation body, and part of the power connection structure extends out of the plastic encapsulation body.

13. The power packaging structure according to claim 1, wherein: The distance between the bottom of the annular slot structure and the electrical connection component on the top surface of the first substrate is greater than or equal to a set threshold, and the set threshold is used to represent the electrical insulation requirement of the package.

14. A method for preparing a power packaging structure, characterized in that: include: Providing a first substrate, and disposing a circuit on a top surface of the first substrate; Mounting a first power chip on the top surface of the first substrate, and electrically interconnecting the first power chip and the circuit on the top surface of the first substrate; forming N signal lead-out structures on the top surface of the first substrate; After forming the N signal lead-out structures, the bottom surface of the first substrate is placed in a lower plastic encapsulation mold, and an upper plastic encapsulation mold and the lower plastic encapsulation mold are combined, wherein the upper plastic encapsulation mold is provided with a plurality of annular sleeve-shaped structures arranged at intervals along a direction toward the top surface of the first substrate, and N of the plurality of annular sleeve-shaped structures each correspond to one of the signal lead-out structures, and the N annular sleeve-shaped structures and the corresponding signal lead-out structure each form a closed annular sleeve space; A plastic encapsulation material is injected between the lower plastic encapsulation mold and the upper plastic encapsulation mold to form a plastic encapsulation body, wherein the plastic encapsulation body covers the top surface of the first substrate and the first power chip. A plurality of first slot structures are formed in the plastic encapsulation body, and the plurality of first slot structures are spaced apart from each other. The plurality of first slot structures include N hole-shaped slot structures and M annular slot structures. Each hole-shaped slot structure exposes a corresponding signal lead-out structure. The outer contour of the hole-shaped slot structure is the same as that of the annular slot structure. M is a positive integer, and M≥0.

15. An electronic device, characterized in that: The power packaging structure comprises the power packaging structure according to any one of claims 1 to 13.

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